JP3946740B2 - Liquid crystal display - Google Patents

Description

  The present invention relates to a liquid crystal display device used for information devices such as word processors, notebook computers, various video devices and game devices, portable VCRs, digital cameras, and the like, and more particularly, outdoors and indoors. The present invention relates to a liquid crystal display device that is used together, and a liquid crystal display device that is used in an environment where the lighting environment changes rapidly, such as an automobile, an aircraft, and a ship.

  Conventionally, as a self-luminous display device capable of electrically rewriting display contents, a cathode ray tube (CRT), an electroluminescence (EL) element, a plasma display panel (PDP) Etc. have been put to practical use.

  However, since the self-luminous display device emits display light itself and uses it for display, it has a problem that power consumption is large. Furthermore, since the light-emitting surface of the self-luminous display device itself is a display surface having a high reflectance, when the self-luminous display device is used, the ambient light in the usage environment is stronger than the light emission luminance. For example, a so-called washout phenomenon in which display light cannot be observed under direct sunlight is unavoidable.

  On the other hand, a liquid crystal display device is practically used as a color display that displays characters and images by adjusting the amount of light transmitted from a specific light source without emitting display light itself. The liquid crystal display (LCD) can be roughly classified into a transmission type liquid crystal display device and a reflection type liquid crystal display device.

  Among them, what is currently widely used as a color liquid crystal display device is a transmissive liquid crystal display device using a light source called a so-called background illumination (backlight) on the back side of the liquid crystal cell. The transmissive liquid crystal display device has advantages such as thinness and light weight, and its application is expanding in various fields. On the other hand, it consumes a large amount of power to emit background light (backlight). However, a relatively large amount of power is required even though the amount of power used for modulating the transmittance of the liquid crystal is small.

  However, in such a transmissive liquid crystal display device (that is, a transmissive color liquid crystal display device), the washout phenomenon seen in the self-luminous display device is reduced. This is because the reflectance of the display surface of the color filter layer used for the transmissive color liquid crystal display device is reduced by a technique for reducing the reflectance of the color filter layer using a black matrix.

  However, even when a transmissive color liquid crystal display device is used, it is difficult to observe the display light when the ambient light is very strong and the display light is relatively weak. For this reason, in order to solve such a problem, if the background illumination light is further increased, a problem that more power is consumed is brought about.

  In contrast to the light emitting display device and the transmissive liquid crystal display device as described above, the reflective liquid crystal display device performs display using ambient light, and thus can obtain display light proportional to the ambient light amount. For this reason, the reflective liquid crystal display device has the principle advantage that the above-described washout phenomenon does not occur, and in a very bright place where it is exposed to direct sunlight, the display can be observed more clearly. Furthermore, since the reflective liquid crystal display device does not require background illumination (backlight) in its display, it has the advantage of being able to reduce the power required to emit the background illumination (backlight). ing. For this reason, the reflective liquid crystal display device is particularly suitable for outdoor use such as a portable information terminal device, a digital camera, and a portable video camera.

  However, in these conventional reflective liquid crystal display devices, since ambient light is used for display, the display luminance is very dependent on the surrounding environment, and the display content cannot be confirmed in an environment where the ambient light is weak. Has the problem. In particular, when a color filter used for realizing color display (color display) is used, the display is further darkened because the color filter absorbs light. Therefore, in such a case, the above problem becomes even more remarkable.

  Therefore, an illumination device called a front light has been developed as auxiliary illumination so that the reflective liquid crystal display device can be used even in an environment with low ambient light. In the reflective liquid crystal display device, a reflector is installed on the back surface of the liquid crystal layer, and background illumination (backlight) unlike the transmissive liquid crystal display device cannot be used. For this reason, the illumination device (front light) used for the reflective liquid crystal display device illuminates the reflective liquid crystal display device from the front, that is, from the display surface side.

  On the other hand, as a liquid crystal display device that takes advantage of the reflective liquid crystal display device and enables use in an environment where ambient illumination light is weak, a part of incident light is transmitted and the remaining incident light is reflected. A liquid crystal display device using a so-called semi-transmissive reflective film has been put into practical use. Such a liquid crystal display device using both transmitted light and reflected light is generally called a transflective liquid crystal display device.

  For example, Japanese Patent Application Laid-Open No. 59-218483 (corresponding to Japanese Patent Application No. 58-28885) and the like modulate the transmitted light intensity such as TN (twisted nematic) method and STN (super twisted nematic) method. A transflective liquid crystal display device that performs brightness modulation using a liquid crystal display method is disclosed. Japanese Laid-Open Patent Publication No. 7-318929 discloses a transflective liquid crystal display device in which a reflective film disposed in the vicinity of a liquid crystal layer has translucency. Further, JP-A-6-160878 discloses a transmissive liquid crystal display device using an in-plane switching method as a technique for realizing a wide viewing angle.

  However, the transflective liquid crystal display device described in Japanese Patent Application Laid-Open No. 59-218483 has a problem as shown below because a transflective film is disposed on the back surface of the liquid crystal cell as viewed from the observer side. It has points (1) and (2).

  That is, first, (1) it is difficult to set the brightness that affects the visibility of display. In other words, when the brightness of the transflective liquid crystal display device is set in accordance with the brightness when performing reflective display, it is necessary to set the brightness high for use under conditions where ambient light is insufficient. is there. However, for example, if the transmittance of the polarizing plate used in the TN mode is set high in order to increase the brightness, the contrast ratio defined by dividing the brightness of the bright display by the brightness of the dark display is insufficient in the transmissive display. And worsen the visibility. On the other hand, when the above brightness is set in accordance with the brightness for transmissive display, it is desirable to set the brightness so as to increase the contrast ratio. However, in this case, the brightness is insufficient in the reflective display. Worsens visibility.

  In addition, in (2) reflective display, the light passing through the liquid crystal layer sandwiched between the substrates is reflected by the reflective film provided on the back surface of the liquid crystal cell to observe the display. Image), which causes a reduction in resolution and makes high-resolution display difficult.

  Further, in the transflective liquid crystal display device described in the above-mentioned Japanese Patent Application Laid-Open No. 7-318929, since the reflective film itself has translucency, the optical design suitable for the reflective display unit and the transmissive display unit is not good. It has the problem that it is possible.

  Further, the in-plane switching method disclosed in the above-mentioned JP-A-6-160878 is used in a transmissive liquid crystal display device, but the liquid crystal alignment on the comb-shaped electrode does not contribute to display. This is not because the electrode wiring is often made of a non-transparent metal, but because the change in liquid crystal alignment is insufficient for transmissive display.

  Therefore, in order to solve these problems, the inventors of the present application tried to apply a display method used for a reflective liquid crystal display capable of suppressing parallax to a transflective liquid crystal display device. Specifically, (a) a GH (guest host) system in which a liquid crystal composition in which a dichroic dye (dichroic dye) is mixed is arranged in the liquid crystal layer, and (b) reflection using a single polarizing plate. Two types of liquid crystal display systems (hereinafter abbreviated as “single polarizing plate system”) have been studied intensively for transflective display.

  When considering the use of a display method that does not generate parallax, as shown in the two methods (a) and (b) above, a reflective film is disposed so as to be in close contact with the liquid crystal layer, and transmitted light in addition to reflected light. In order to be able to use it for display, the reflective film is provided with a transmissive aperture portion.

  As a result, the following problems were further clarified. First, (a) In the GH method, when the concentration of the dichroic dye mixed in the liquid crystal composition is adjusted so as to be suitable for reflective display, the transmissive display portion has a high brightness but lacks a contrast ratio, and provides a good display. Can't get. On the other hand, when the concentration of the dichroic dye mixed in the liquid crystal composition is adjusted so as to be suitable for transmissive display, a good contrast ratio can be obtained in the transmissive display portion, but the brightness is reduced in the reflective display portion, which is good. A reflection display cannot be obtained.

  (B) When the single-polarizing plate system is used for transflective display, the setting of the liquid crystal alignment and the liquid crystal layer thickness for determining the optical characteristics, or the voltage applied to the liquid crystal for driving them is set in the reflective display section. There are two ways to set the display in accordance with the transmissive display, or to add a polarizing plate to the back of the display surface to perform transmissive display (two-plate polarizing plate method), and to set the transmissive display.

  First, display in the transmissive display unit when the liquid crystal layer thickness is set to a layer thickness suitable for reflective display will be described. When the liquid crystal layer suitable for reflective display is set, the amount of change in the polarization state due to the orientation change due to the external field such as the electric field of the liquid crystal layer is incident through the liquid crystal layer from the front, that is, from the display surface side. The light is again emitted to the display surface through the liquid crystal layer, so that a sufficient contrast ratio can be obtained by reciprocating the liquid crystal layer. However, in this setting, the amount of change in the polarization state of the light that has passed through the liquid crystal layer is insufficient in the transmissive display unit. For this reason, in addition to the polarizing plate installed on the viewer side of the liquid crystal cell used for reflective display, that is, on the display surface side, a polarizing plate used only for transmissive display is installed on the back side of the liquid crystal cell when viewed from the viewer side. However, sufficient display cannot be obtained in the transmissive display unit. In other words, when the alignment conditions of the liquid crystal layer are set to the alignment conditions of the liquid crystal layer suitable for reflective display (liquid crystal layer thickness, liquid crystal alignment, etc.), the transmissive display section has insufficient brightness or sufficient brightness. However, the transmittance for dark display does not decrease, and a contrast ratio sufficient for display cannot be obtained.

  More specifically, when performing reflective display, the alignment state of the liquid crystal in the liquid crystal layer is such that a phase difference of approximately ¼ wavelength is given to light that passes through the liquid crystal layer only once. It is controlled by the voltage applied to. Using the liquid crystal layer set to give such a phase difference to the light passing through the liquid crystal layer, only the voltage modulation that gives the phase modulation of ¼ wavelength to the light passing through the liquid crystal layer is performed. If the transmissive display section is sufficiently reduced in the dark display, when the transmissive display section is bright display, about half the intensity of light is absorbed by the polarizing plate on the light exit side. A bright display cannot be obtained. In addition, if an optical element such as a polarizing plate or a phase difference compensator is arranged to increase the brightness when the transmissive display portion is in bright display, the brightness when the transmissive display portion is in dark display is the same as that during bright display. The brightness is about ½ of the brightness, and the display contrast ratio is insufficient.

  Next, display on the reflective display unit when the alignment condition of the liquid crystal layer is set to a condition suitable for transmissive display will be described. When reflective display is performed with a liquid crystal layer suitable for transmissive display, the liquid crystal alignment is controlled by voltage modulation so that the polarization state of light that passes through the liquid crystal layer only once is modulated between two substantially orthogonal polarization states. There is a need. Here, the two orthogonal polarization states may be two linearly polarized light having orthogonal vibration planes, left and right circularly polarized light, and two ellipses having the same ellipticity. It may be polarized light whose major axis direction is orthogonal and the rotation direction of the optical electric field is reversed. In order to realize the modulation of the polarization state between the combinations of these two orthogonal polarization states, voltage modulation is performed in the liquid crystal layer so that a half-wave phase difference is given to the transmitted light. There is a need. When the polarization state of light is modulated between two orthogonal polarization states in this way, in any case, transmission is performed by the action of the polarizing plate and the action of the phase difference compensator used as necessary. In display, sufficient brightness and contrast ratio can be realized.

  However, when the above-described liquid crystal layer is set to realize such control, in the transmissive display, the change in the reflectance is brightly displayed in the reflective display while changing only once from the bright display to the dark display. When the liquid crystal orientation changing means is the same (for example, when the liquid crystal layer has the same layer thickness and the same initial orientation and is driven with the same voltage) Bright and dark display cannot be realized. The problem that occurs in the cases (a) and (b) is the same as in the transflective liquid crystal display device described in Japanese Patent Laid-Open No. 7-318929.

  In addition, the press-sensing input device (touch panel) used to overlap the liquid crystal display device has a problem that visibility is easily deteriorated because it itself has reflectivity for light, and in particular, This tendency is remarkable in the reflective liquid crystal display device.

  In addition, many front light units that improve the visibility of reflective liquid crystal display devices in environments with low ambient light have a flat light pipe structure, and the display content is observed through this light pipe. The problem is that sex is likely to deteriorate.

  The present invention has been made in view of the above-described problems, and its purpose is excellent in visibility and high-resolution display, and both reflected light and transmitted light can be used for display. The object is to provide a liquid crystal display device. Another object of the present invention is to provide a liquid crystal display device that is excellent in visibility and capable of high-resolution color display, and can use both reflected light and transmitted light for display. .

  As a result of intensive investigations to achieve the above object, the inventors of the present application have found that the cause of the problems of the conventional liquid crystal display device is the alignment of the liquid crystal layer at the same time in both the GH method and the polarizing plate method. Has come to the conclusion that the reason is that the transmissive display portion and the reflective display portion are set in the same manner, and the present invention has been completed.

  Here, the orientation of the liquid crystal layer is not only the average orientation direction of the liquid crystal molecules at a certain point of the liquid crystal layer, but also the coordinate dependence of the average orientation direction with respect to the coordinates taken in the normal direction of the layer of the liquid crystal layer. Is also shown.

  That is, a liquid crystal display device according to the present invention is a liquid crystal display having a pair of substrates having alignment means on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates in order to solve the above problems. A liquid crystal display device including an element, wherein a reflective display portion in which a reflection means is formed on a substrate opposite to the display surface side of the pair of substrates, and the reflection means is formed The reflective display unit and the transmissive display unit simultaneously exhibit different liquid crystal orientations, and a polarizing plate is disposed on the non-contact surface side of the pair of substrates with the liquid crystal layer, When no voltage is applied to the liquid crystal layer, dark display is performed on the reflective display portion and the transmissive display portion.

  According to the above configuration, the liquid crystal alignment has different alignment states at the same time. For example, when a dye such as a dichroic dye is used for display, light absorption (absorption rate) and optical anisotropy are used. In some cases, the magnitude of the modulation amount of each optical physical quantity such as a phase difference can be changed for each region having a different liquid crystal alignment. For this reason, according to said structure, the transmittance | permeability or reflectance based on the magnitude | size of the modulation amount of the optical physical quantity according to the orientation state of a liquid crystal layer can be obtained, and, thereby, a transmissive display part and a reflective display part Thus, it is possible to set the optical parameters independently. Therefore, according to the above configuration, there is no parallax, a high contrast ratio can be realized, and it is possible to improve visibility when the surroundings are dark, and good visibility even when ambient light is strong Can be obtained. Therefore, according to the above configuration, a transflective liquid crystal display device that is excellent in visibility, capable of high-resolution display, and can use both reflected light and transmitted light for display is provided. be able to.

  The liquid crystal display device performs dark display when no voltage is applied. In the liquid crystal display device, so-called NB (normally black) whose reflectance and transmittance increase with the application of voltage. ) Mode display can be realized. Further, the liquid crystal display device described above can match the brightness of the display between the reflective display portion and the transmissive display portion, and can realize a display with excellent visibility.

  In addition, when the degree of modulation of each optical physical quantity such as the light absorption amount and the phase difference due to optical anisotropy is changed independently between the reflective display unit and the transmissive display unit, the alignment direction of the liquid crystal due to voltage application Even when the entire region for use in displaying the liquid crystal layer is substantially the same, the region where the liquid crystal layer thickness of the liquid crystal layer is different is substantially the same as when the orientation direction of the liquid crystal layer is changed in the region. Has an effect. In particular, in the GH method using a dye such as a dichroic dye and the polarizing plate method using birefringence and optical rotation phenomenon, the light absorption and birefringence phenomena generated in the liquid crystal layer are as follows. These are phenomena associated with the propagation of light, and each phenomenon has a relationship between the propagation distance of light in the liquid crystal layer and the degree of those phenomena. Further, since the display light passes twice through the liquid crystal layer in the reflective display portion and only once through the liquid crystal layer in the transmissive display portion, the thickness of the liquid crystal layer is substantially the same when the liquid crystal orientation is substantially the same. However, when the reflective display unit and the transmissive display unit are set in the same manner, sufficient brightness and contrast ratio cannot be obtained, and the above-described problem cannot be solved.

  Accordingly, in order to solve the above problems, a liquid crystal display device according to the present invention includes a pair of substrates having alignment means on opposite surfaces, and a liquid crystal layer sandwiched between the pair of substrates. A liquid crystal display device provided with a display element, wherein a reflective display portion is formed on a substrate opposite to the display surface side of the pair of substrates with a liquid crystal layer interposed therebetween, and the reflective means is formed. The liquid crystal layer in the region used for display has at least two different liquid crystal layer thicknesses, and of the different liquid crystal layer thicknesses, the liquid crystal layer thickness of the reflective display unit is When the polarizing plate is disposed on the non-contact surface side of the pair of substrates with the liquid crystal layer and no voltage is applied to the liquid crystal layer, the reflective display unit and the transmissive display unit Characterized by performing dark display To have.

  According to the above configuration, it is possible to obtain a transmittance or a reflectance based on the magnitude of the modulation amount of the optical physical quantity in the regions having different liquid crystal layer thicknesses. Can be set independently. Therefore, according to the above configuration, there is no parallax, a high contrast ratio can be realized, and it is possible to improve visibility when the surroundings are dark, and good visibility even when ambient light is strong Can be obtained. Therefore, according to the above configuration, a transflective liquid crystal display device that is excellent in visibility, capable of high-resolution display, and can use both reflected light and transmitted light for display is provided. be able to.

  The liquid crystal display device performs dark display when no voltage is applied, and the liquid crystal display device performs display in a so-called NB mode in which the reflectance and transmittance increase with the application of voltage. Can be realized. In addition, the liquid crystal display device described above can match the brightness of the display between the reflective display portion and the transmissive display portion, and can realize a display with excellent visibility.

  In each of the liquid crystal display devices, as the alignment means applied to the pair of substrates, for example, an alignment film having an action of aligning the liquid crystal vertically with respect to the pair of substrates is used. According to the above configuration, it is possible to realize a transflective liquid crystal display device that can perform good display on both the reflective display unit and the transmissive display unit.

  In addition, a liquid crystal having a negative dielectric anisotropy is used as the liquid crystal forming the liquid crystal layer in each liquid crystal display device.

  As described above, the liquid crystal display device according to the present invention includes a liquid crystal display device including a pair of substrates each having an alignment means on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates. A reflection display unit in which reflection means is formed on a substrate on the opposite side of the liquid crystal layer from the display surface side of the pair of substrates, and a transmission display unit in which the reflection means is not formed The reflective display portion and the transmissive display portion simultaneously exhibit different liquid crystal orientations, and a polarizing plate is disposed on the non-contact surface side of the pair of substrates with the liquid crystal layer, and a voltage is applied to the liquid crystal layer. When not, dark display is performed on the reflective display portion and the transmissive display portion.

  According to the above configuration, the liquid crystal alignment has different alignment states at the same time. For example, when a dye such as a dichroic dye is used for display, light absorption (absorption rate) and optical anisotropy are used. In some cases, the magnitude of the modulation amount of each optical physical quantity such as a phase difference can be changed for each region having a different liquid crystal alignment. For this reason, according to said structure, the transmittance | permeability or reflectance based on the magnitude | size of the modulation amount of the optical physical quantity according to the orientation state of a liquid crystal layer can be obtained, and, thereby, a transmissive display part and a reflective display part Thus, it is possible to set the optical parameters independently. Therefore, according to the above configuration, it is possible to provide a transflective liquid crystal display device that is excellent in visibility and capable of high-resolution display and can use both reflected light and transmitted light for display. There is an effect that can be. In addition, according to the above configuration, dark display is performed when no voltage is applied, so that display in the so-called NB mode can be realized, and display brightness and darkness can be improved between the reflective display unit and the transmissive display unit. Since they can be matched, there is also an effect that a display with excellent visibility can be realized.

  As described above, the liquid crystal display device according to the present invention includes a liquid crystal display device including a pair of substrates each having an alignment means on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates. A reflection display unit in which reflection means is formed on a substrate on the opposite side of the liquid crystal layer from the display surface side of the pair of substrates, and a transmission display unit in which the reflection means is not formed The liquid crystal layer in a region used for display has at least two different liquid crystal layer thicknesses, and the liquid crystal layer thickness of the reflective display unit among the different liquid crystal layer thicknesses is the liquid crystal layer of the transmissive display unit The polarizing plate is arranged on the non-contact surface side of the pair of substrates with the liquid crystal layer, and when the voltage is not applied to the liquid crystal layer, the reflective display unit and the transmissive display unit perform dark display. .

  According to the above configuration, it is possible to obtain a transmittance or a reflectance based on the magnitude of the modulation amount of the optical physical quantity in the regions having different liquid crystal layer thicknesses. Can be set independently. Therefore, according to the above configuration, it is possible to provide a transflective liquid crystal display device that is excellent in visibility and capable of high-resolution display and can use both reflected light and transmitted light for display. There is an effect that can be. In addition, according to the above configuration, dark display is performed when no voltage is applied, so that display in the so-called NB mode can be realized, and display brightness and darkness can be improved between the reflective display unit and the transmissive display unit. Since they can be matched, there is also an effect that a display with excellent visibility can be realized.

  The liquid crystal display device according to the present invention is characterized in that the liquid crystal alignment of the reflective display portion and the liquid crystal alignment of the transmissive display portion can take different states at the same time. Here, the liquid crystal alignment indicates not only the average alignment direction of liquid crystal molecules at a certain point of the liquid crystal layer but also the coordinate dependency of the average alignment direction with respect to the coordinates taken in the normal direction of the layered liquid crystal layer. Shall. Therefore, in the present invention, a method for realizing different liquid crystal alignments in the reflective display unit and the transmissive display unit and an alignment mechanism used in the method will be roughly classified into three types.

  In the first method, the liquid crystal alignment of the reflective display unit and the liquid crystal alignment of the transmissive display unit are made different by using an alignment mechanism that is prepared so that a certain condition of the liquid crystal layer is different between the transmissive display unit and the reflective display unit. Is the method.

  As the first method, specifically, for example, (1) a method of using an alignment mechanism in which the liquid crystal alignment is twisted so that the transmissive display unit and the reflective display unit have completely different twist angles, (2) Examples thereof include a method using an alignment mechanism that greatly changes the tilt angle of the liquid crystal alignment with respect to the substrate. The first method includes (3) a method in which different liquid crystal materials are arranged in the transmissive display unit and the reflective display unit, and (4) the type and density of the dye mixed in the liquid crystal material. And the reflective display unit (in this case, the same liquid crystal material may be used for the transmissive display unit and the reflective display unit). The mechanism made when realizing the method is provided as the orientation mechanism of the present invention. The first method and the alignment mechanism used in the method may be a combination of the methods (1) to (4). Depending on the method and the alignment mechanism used in the method, Different liquid crystal alignments can be realized in the reflective display portion and the transmissive display portion.

  The second method is a method in which the liquid crystal orientation is made different between the transmissive display portion and the reflective display portion by means of display content rewriting means for rewriting the display content as time passes (that is, the liquid crystal orientation is changed between the transmissive display portion and the reflective display portion In which the orientation mechanism is the same as the display content rewriting means. As the display content rewriting means used when this method is adopted, an existing display rewriting means can be used.

  Specifically, as the second method, for example, (5) a method of rewriting liquid crystal alignment by a method of using different electrodes as the alignment mechanism in the transmissive display unit and the reflective display unit, that is, rewriting the display contents A method of changing the voltage itself used as the means between the transmissive display unit and the reflective display unit can be employed. Further, as the second method, (6) the electrodes are the same, but a method of changing the voltage substantially applied to the liquid crystal alignment may be used. When the method (6) is adopted, for example, an insulator (for example, an insulating film) having a different layer thickness is disposed between the liquid crystal layer and the electrode that drives the liquid crystal display layer and the transmissive display unit. Thus, the liquid crystal alignment of the transmissive display unit driven by the common electrode and the liquid crystal alignment of the reflective display unit may be changed. Further, (7) a method of changing the direction of the electric field between the transmissive display portion and the reflective display portion may be used. For example, when display is performed by changing the liquid crystal alignment direction in the plane of the liquid crystal layer by an electrode group that is arranged in parallel with one of the substrates sandwiching the liquid crystal layer and applies different potentials to the liquid crystal layer, Since the liquid crystal alignment is greatly different, regions having different liquid crystal alignment may be used for the reflective display and the transmissive display, respectively. Furthermore, a method of applying different potentials to the liquid crystal layers aligned perpendicularly to the substrate by the same electrode group may be employed. When the second method is adopted, for example, an electrode, an insulator, or a combination thereof used in realizing the method corresponds to the alignment mechanism of the present invention, and the obtained liquid crystal display device is These orientation mechanisms are provided.

  The third method is a method in which the liquid crystal alignment itself is not greatly different, but the thickness of the liquid crystal layer, which is an element that determines the optical characteristics, is made different between the reflective display portion and the transmissive display portion. For example, an insulating film formed in a different film thickness between the reflective display portion and the transmissive display portion, a substrate formed in a different layer thickness or shape between the reflective display portion and the transmissive display portion, etc. Used as

  When the third method is employed, the liquid crystal alignment may be a uniformly twisted liquid crystal alignment, for example, a TN method used in a liquid crystal display device using two polarizing plates. In this case, the liquid crystal alignment is aligned parallel to the substrates between the substrates sandwiching the liquid crystal layer, and the alignment direction is twisted while changing the direction in the substrate plane according to the distance from one substrate. . If this liquid crystal alignment is used for the reflective display portion and the transmissive display portion by changing the liquid crystal layer thickness, the optical characteristics differ depending on the thickness of the liquid crystal layer, so that a good display can be realized in both the reflective display portion and the transmissive display portion.

  Also, in the GH method, since there is an effect similar to that in the case where the dye concentration is substantially changed by changing the liquid crystal layer thickness, the liquid crystal alignment itself may be substantially the same in the reflective display portion and the transmissive display portion. Good display can be realized in each of the reflective display portion and the transmissive display portion.

  As described above, the method of realizing different liquid crystal alignment in the reflective display portion and the transmissive display portion and the alignment mechanism used in the method are roughly classified into three types, and are realized by these methods and alignment mechanisms. The liquid crystal display method used in the liquid crystal display device according to the present invention is not particularly limited, and may be appropriately selected from the group of methods used for displaying the alignment change of the liquid crystal. Specifically, the liquid crystal display method used in the present invention is a mode in which the nematic phase of the liquid crystal composition is used for display, for example, TN mode, STN mode, nematic bistable mode, vertical alignment mode, Various modes such as a hybrid alignment mode and an ECB (electrically controlled biriefringence) mode can be used. Further, a mode using scattering, for example, a polymer dispersion type liquid crystal mode, a dynamic scattering system, and the like can also be used as the liquid crystal display system used in the present invention. Further, since the surface-stabilized ferroelectric liquid crystal display method using the ferroelectric liquid crystal composition and the thresholdless switching antiferroelectric liquid crystal display method using the antiferroelectric liquid crystal also use the orientation change for the display, It can be used as the liquid crystal display method used in the above.

  When the third method is adopted, the liquid crystal display method used in the present invention may be a method using optical rotatory modulation like the TN method, and the retardation modulation like the ECB mode. The method used may be used, or a method in which the light absorption rate (absorbance) is modulated, such as the GH method. In the case of adopting the third method, the liquid crystal layer thickness is a major determinant of the optical characteristics including these methods, and the liquid crystal layer thickness is set thick in the transmissive display portion. In addition, it is possible to employ all methods in which setting the thin liquid crystal layer thickness in the reflective display portion has an effect of realizing good display characteristics.

  In the present invention, as described above, the liquid crystal display device includes a liquid crystal display element including a pair of substrates having alignment means on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates. A display device comprising an alignment mechanism for causing any and different regions used for display in the liquid crystal layer to simultaneously take at least two different alignment states, and having different alignment states in the liquid crystal layer Reflecting means is arranged in at least one of the regions to be shown, and the regions showing the different orientation states are used for the reflective display portion that performs reflective display and the transmissive display portion that performs transmissive display, The transmittance or reflectance based on the amount of modulation of the optical physical quantity according to the orientation state of the layer can be obtained, and there is no parallax and a high contrast ratio can be realized. As a result, it is possible to improve the visibility when the surroundings are dark, and it is possible to obtain good visibility even when the ambient light is strong.

  In addition, when the degree of modulation of each optical physical quantity such as the light absorption amount and the phase difference due to optical anisotropy is changed independently between the reflective display unit and the transmissive display unit, the alignment direction of the liquid crystal due to voltage application Even when the entire region for use in displaying the liquid crystal layer is substantially the same, the region where the liquid crystal layer thickness of the liquid crystal layer is different is substantially the same as when the orientation direction of the liquid crystal layer is changed in the region. Since the liquid crystal display device according to the present invention has an action, the liquid crystal display device includes a pair of substrates each having an alignment means on opposite surfaces, and a liquid crystal layer sandwiched between the pair of substrates. In the liquid crystal display device, a region used for display in the liquid crystal layer is formed of a region having at least two different liquid crystal layer thicknesses, and each region having the different liquid crystal layer thickness is transmitted through the reflective display unit. Used for display With, at least the reflective display portion is arranged, reflection means, the liquid crystal layer thickness of the reflective display unit may be configured to be smaller than the transmissive display section.

  Even in the above-described configuration, it is possible to obtain transmittance or reflectance based on the amount of modulation of the optical physical quantity in regions having different liquid crystal layer thicknesses. It can be set independently. Therefore, according to the above configuration, there is no parallax, a high contrast ratio can be realized, and it is possible to improve visibility when the surroundings are dark, and good visibility even when ambient light is strong Can be obtained.

  Hereinafter, in particular, a liquid crystal display device that performs good reflective display and good transmissive display by changing the thickness of the liquid crystal layer between the reflective display portion and the transmissive display portion, mainly the first embodiment and the second embodiment. Will be described.

[Embodiment 1]
In this embodiment mode, a liquid crystal display device using a GH mode will be described below mainly with reference to FIG.

  FIG. 1 is a cross-sectional view of a main part of the liquid crystal display device according to the first embodiment. As shown in FIG. 1, the liquid crystal display device includes a liquid crystal cell 100 (liquid crystal display element) and, if necessary, a backlight 13 (illumination device) as background illumination means. The liquid crystal cell 100 and the backlight 13 are arranged in the order of the liquid crystal cell 100 and the backlight 13 from the observer (user) side.

  As shown in FIG. 1, the liquid crystal cell 100 includes an electrode substrate 101 (a first substrate) having an alignment film 2 on the side where the liquid crystal layer 1 is in contact with the liquid crystal layer 1 (interface on the first substrate in contact with the liquid crystal layer 1). 1 substrate) and an electrode substrate 102 (second substrate) provided with an alignment film 3 on the side in contact with the liquid crystal layer 1 (interface on the second substrate in contact with the liquid crystal layer 1). is doing.

  The electrode substrate 101 is provided with an electrode 6 (voltage applying means) for applying a voltage to the liquid crystal layer 1 on a substrate 4 made of a light-transmitting glass substrate or the like so as to cover the electrode 6. An alignment film 2 (orientation mechanism) subjected to rubbing treatment is formed.

  On the other hand, in order to apply a voltage to the liquid crystal layer 1, the insulating film 11 is provided on the electrode substrate 102 provided opposite to the electrode substrate 101 with the liquid crystal layer 1 interposed therebetween. Thus, an electrode 7 (voltage applying means) as a counter electrode facing the electrode 6 is formed.

  The insulating film 11 is used for display in the liquid crystal layer 1 so that the region used for display in the liquid crystal layer 1 has at least two different liquid crystal layer thicknesses (two types in the present embodiment). The regions corresponding to the regions are formed so as to have partially different film thicknesses. More specifically, the insulating film 11 is formed in a region corresponding to the transmissive display unit 10 so as to be thinner than a region corresponding to the reflective display unit 9.

  In a region corresponding to the reflective display portion 9 in the electrode substrate 102, a reflective film 8 (reflecting means) that covers the electrode 7 is formed, and further, an alignment film 3 (alignment mechanism) that has been subjected to a rubbing process includes these It is formed so as to cover the electrode 7 and the reflective film 8.

  Here, the electrodes 6 and 7 are transparent electrodes formed of, for example, ITO (indium tin oxide). Further, a voltage for generating an electric field in the liquid crystal layer 1 is applied to the electrodes 6 and 7, and the display is controlled by applying a voltage in accordance with the display contents. ing.

  The reflective film 8 has light reflectivity and is made of, for example, a metal such as aluminum or silver, a dielectric multilayer mirror, or the like. When the reflective film 8 is made of a conductor, the reflective film 8 may also function as an electrode instead of the electrode 7. That is, the reflective film 8 may be a reflective pixel electrode that doubles as a liquid crystal driving electrode that drives the liquid crystal layer 1 and a reflecting means. Further, the reflective film 8 may be a color reflective film that reflects light in a wavelength band appropriately selected from visible light.

  In addition, the material of each member which comprises the said electrode substrate 101 * 102, a formation method, etc. are not necessarily limited to said description, A conventionally well-known material and a usual method can be used. Further, the configuration of the liquid crystal display device is not limited to the above-described configuration. For example, the liquid crystal cell 100 has a configuration in accordance with a signal from a touch panel (pressed coordinate detection type input unit) described in an embodiment described later. You may have the structure by which a voltage is applied to the electrodes 6 * 7 corresponding to the reflective display part 9 and the transmissive display part 10 directly from the outside. Moreover, you may have the structure by which active elements, such as a TFT element and MIM, are provided as a switching element.

  As shown in FIG. 1, the electrode substrates 101 and 102 are opposed to each other so that the alignment films 2 and 3 face each other, and are bonded together using an encapsulating sealant or the like, and a liquid crystal composition is introduced into the gaps. A liquid crystal layer 1 is formed.

  The backlight 13 is disposed on the back side of the liquid crystal cell 100 as viewed from the observer (user), that is, on the back side of the electrode substrate 102. The backlight 13 is mainly composed of a light source 13a and a light guide 13b. The light source 13a is disposed, for example, along the side surface of the light guide 13b. Thus, the light guide 13b has, for example, a side surface on the light source 13a disposed side as an incident surface, and light incident from the light source 13a is illuminated. The light is emitted to the liquid crystal cell 100 which is an object. As the backlight 13, an existing lighting device can be used.

  In the liquid crystal display device having the above-described configuration, in the reflective display unit 9 on which the reflective film 8 is formed, the reflection intensity of ambient light incident on the display surface from the substrate 4 side, that is, the observer side, is controlled by changing the liquid crystal alignment. And display. Further, in the transmissive display unit 10 in which the reflective film 8 is not formed, display is performed by controlling the transmitted light intensity of light incident on the display surface from the substrate 5 side by changing the liquid crystal alignment. In this case, illumination light from the backlight 13 installed on the back surface of the liquid crystal cell 100 may be used as necessary.

  As described above, the liquid crystal display device shown in FIG. 1 is manufactured to have different liquid crystal layer thicknesses in the reflective display unit 9 and the transmissive display unit 10. Thereby, the liquid crystal display device has substantially different liquid crystal alignments in the reflective display section 9 and the transmissive display section 10.

  Here, a configuration of a liquid crystal display device for obtaining different liquid crystal film thicknesses in the reflective display unit 9 and the transmissive display unit 10 will be described below.

  In order to obtain different liquid crystal film thicknesses in the reflective display unit 9 and the transmissive display unit 10, for example, as shown in FIG. 1, the insulating film 11 is formed with different film thicknesses in the reflective display unit 9 and the transmissive display unit 10. What is necessary is just to form so that it may have.

  Note that the configuration for changing the liquid crystal layer thickness between the reflective display unit 9 and the transmissive display unit 10 is provided by at least one of the substrates sandwiching the liquid crystal (that is, the electrode substrates 101 and 102). All you need is it.

  Therefore, the insulating film 11 may be disposed not on the substrate 5 but on the substrate 4. However, even in such a case, the reflective film 8 is formed on the substrate 5 on the electrode substrate 102 side (that is, the display surface side (electrode substrate 101 side) opposite to the liquid crystal layer 1). Is done.

  In the liquid crystal display device shown in FIG. 1, the reflective display portion is obtained by changing the film thickness of the insulating film 11 between the region corresponding to the reflective display portion 9 and the region corresponding to the transmissive display portion 10 in the insulating film 11. 9 and the transmissive display unit 10 are configured to change the thickness of the liquid crystal layer. However, the substrate 4 or the substrate 5 itself is formed in the same shape as the insulating film 11 shown in FIG. The liquid crystal layer thickness may be changed with the display unit 10.

  Further, when the film thickness is changed between the region corresponding to the reflective display unit 9 and the region corresponding to the transmissive display unit 10 in the insulating film 11, the region corresponding to the transmissive display unit 10 as shown in FIG. 1. The insulating film 11 may be formed to be thinner than the thickness of the insulating film 11 in the region corresponding to the reflective display portion 9, or the insulating film 11 may be formed in the region corresponding to the reflective display portion 9. A configuration in which the insulating film 11 is not formed in the region corresponding to the transmissive display portion 10 may be employed.

  Furthermore, in order to keep the liquid crystal layer thickness of the liquid crystal layer 1 in the reflective display unit 9 and the transmissive display unit 10 at a predetermined value, the liquid crystal layer 1 may be provided with a spacer (not shown). The liquid crystal layer thickness may be kept at a predetermined value. For example, when a spherical spacer is arranged on the liquid crystal layer 1, the liquid crystal layer thickness in the reflective display section 9 having a thin liquid crystal layer thickness is substantially equal to the diameter of the spacer.

  The substrate pair prepared as described above, that is, the liquid crystal layer 1 sandwiched between the electrode substrates 101 and 102 is made of a liquid crystal composition as described above. As a liquid crystal display method using the liquid crystal layer 1, for example, as shown in FIG. 1, a liquid crystal composition in which a dichroic dye 12 is mixed with liquid crystal is used, and an electric field is generated in the liquid crystal layer 1 to align the liquid crystal. It is possible to use a GH method in which the orientation direction of the dichroic dye 12 is simultaneously changed and the display is performed using the change in the absorption coefficient due to dichroism.

  Next, the operation of the GH liquid crystal layer 1 and the display principle when the liquid crystal film thickness in the reflective display unit 9 and the liquid crystal layer thickness in the transmissive display unit 10 are different will be described with reference to FIG. .

  When performing display using the liquid crystal display device shown in FIG. 1, the transmissive display unit 10 allows light from the back of the liquid crystal layer 1 such as the backlight 13 to pass through the liquid crystal layer 1 only once, as indicated by arrows. Display is performed by emitting light from the display surface and using it as display light. At this time, the light absorption rate of the dichroic dye 12 mixed in the liquid crystal composition arranged in the liquid crystal layer 1 varies depending on the liquid crystal alignment. For this reason, as shown in the transmissive display unit 10a, the transmissive display unit 10 has a liquid crystal aligned in parallel with the display surface (electrode substrate 101) (hereinafter referred to as parallel alignment). Since the chromatic dye 12 strongly absorbs the light passing through the liquid crystal layer 1, dark display is obtained, and the liquid crystal is aligned perpendicular to the display surface (electrode substrate 101) as shown in the transmissive display portion 10 b (hereinafter referred to as “vertical”). (Referred to as “orientation”), since light absorption by the dichroic dye 12 is weak, a bright display becomes possible.

  On the other hand, in the reflective display unit 9, light incident on the display surface from the observer side is used for display. That is, as shown by the arrow, the light incident on the display surface passes through the liquid crystal layer 1, is reflected by the reflective film 8, passes through the liquid crystal layer 1 again, and is emitted from the display surface to become display light. At this time, as shown in the reflective display section 9a, the reflective display section 9 becomes dark display because the dichroic dye 12 in this part strongly absorbs light when the liquid crystal is aligned in parallel. As shown in FIG. 9b, when the liquid crystal is vertically aligned, light absorption by the dichroic dye 12 is weak, so that a bright display is possible.

  Therefore, a bright display and a dark display can be performed by applying a potential difference between the electrode 6 and the electrode 7 to control the liquid crystal alignment. In this case, the initial alignment state of the liquid crystal is not particularly limited. For example, the liquid crystal may be aligned in parallel when no voltage is applied, or may be twisted. When not applied, it may be vertically aligned. In the former case (that is, when the liquid crystal alignment when no voltage is applied is parallel or twisted), a liquid crystal having positive dielectric anisotropy can be used as the liquid crystal. . On the other hand, in the latter case (that is, when the liquid crystal alignment when no voltage is applied is a vertical alignment), a liquid crystal having a negative dielectric anisotropy can be used as the liquid crystal. Thus, although the initial alignment state of the liquid crystal is not particularly limited, it is necessary to adjust the film thickness of the insulating film 11 so as to obtain a liquid crystal layer thickness suitable for the form of liquid crystal alignment to be used. It is.

  Further, as shown in FIG. 1, in order to easily manufacture the liquid crystal layer 1, the liquid crystal layer 1 includes a reflective display unit 9 and a transmissive display unit 10, or a plurality of display pixels, as in a normal liquid crystal display device. It is preferable to have a structure that communicates with each other.

  Even when the liquid crystal layer 1 communicates between the reflective display unit 9 and the transmissive display unit 10 as described above, if the liquid crystal layer thickness differs between the transmissive display unit 10 and the reflective display unit 9, the final The distance that the light that becomes the display light passes through the liquid crystal layer 1 is the distance that the light passes through the liquid crystal layer 1 only once in the transmissive display portion 10 and the light that passes through the liquid crystal layer 1 in the reflective display portion 9. It is possible to set almost the same with the distance of reciprocating 1.

  Therefore, the reflected brightness of the reflective display unit 9 and the transmitted brightness of the transmissive display unit 10 can be set to substantially the same level, and the contrast ratio in the reflective display unit 9 and the contrast ratio in the transmissive display unit 10 are substantially equal. It can be set to the same level. In other words, in the GH method using light absorption by the dichroic dye 12, changing the liquid crystal layer thickness between the reflective display unit 9 and the transmissive display unit 10 substantially changes the dye concentration. Since there is a similar effect, by changing the liquid crystal layer thickness between the transmissive display unit 10 and the reflective display unit 9, the mixing concentration of the dichroic dye 12 suitable for the reflective display unit 9 and the transmissive display with respect to the liquid crystal composition The mixing concentration of the dichroic dye 12 suitable for the portion 10 can be made substantially equal. Therefore, the liquid crystal layer 1 in which the reflective display unit 9 and the transmissive display unit 10 communicate with each other can realize good display simultaneously on the reflective display unit 9 and the transmissive display unit 10. That is, the reflective display unit 9 and the transmissive display unit 10 have the same display contrast ratio and the same brightness for bright display.

  The lightness in this case indicates the proportion of light incident on the liquid crystal layer 1 that is observed by the observer as display light in the reflective display unit 9 or the transmissive display unit 10, and the contrast ratio is the lightness of bright display. Is defined by dividing by the lightness of dark display.

  In general, when a contrast ratio suitable for reflective display is compared with a contrast ratio suitable for transmissive display, the contrast ratio suitable for transmissive display is required to be higher than the contrast ratio suitable for reflective display. . Therefore, in order to satisfy this requirement, the liquid crystal layer thickness in the transmissive display unit 10 is set to be larger than the liquid crystal layer thickness in the reflective display unit 9 rather than setting the contrast ratio in the reflective display unit 9 and the contrast ratio in the transmissive display unit 10 equal. In order to achieve good display, it is effective that the contrast ratio in the transmissive display unit 10 is greater than the contrast ratio in the reflective display unit 9.

  Hereinafter, the liquid crystal display device according to the present embodiment will be described based on the display principle described above with reference to FIGS. 1 to 3 with specific examples and comparative examples. The liquid crystal display device according to the invention is not limited to the following examples.

[Example 1]
In this embodiment, when no voltage is applied to the liquid crystal layer 1, the liquid crystal is aligned substantially perpendicular to the display surface normal, and the liquid crystal is tilted with respect to the display surface by applying a voltage to the liquid crystal layer 1. A liquid crystal display device using the GH type liquid crystal layer 1 using a liquid crystal with negative dielectric anisotropy aligned for display will be described. First, a manufacturing method of the liquid crystal display device will be described below.

  First, an ITO film having a thickness of 140 nm was formed on a transparent substrate 4 by sputtering, and an electrode 6 (transparent electrode) having a predetermined pattern was produced by etching using photolithography. Note that a glass substrate was used as the substrate 4.

  Next, on the surface of the substrate 4 where the electrode 6 was formed, a vertical alignment film was further arranged by offset printing, and this was baked in an oven at 200 ° C. to form the alignment film 2. Thereafter, the alignment film 2 was subjected to an alignment process by rubbing to produce an electrode substrate 101 as an observer side substrate.

  Here, the vertical alignment film has a property of aligning the liquid crystal in the normal direction of the film surface, and further has a property of tilting the liquid crystal alignment by several degrees from the normal direction by an alignment treatment such as rubbing. Due to this tilt, the liquid crystal alignment after voltage application is further tilted toward the alignment processing direction.

  On the other hand, an insulating photosensitive resin is applied onto the substrate 5 by spin coating, and further, the photosensitive resin does not remain in the transmissive display unit 10 by irradiation with an ultraviolet light mask. The insulating film 11 was patterned so that a thickness of 3 μm was formed. At this time, the pattern edge portion of the insulating film 11 was formed to have a sufficiently gentle step shape so that the electrode 7 formed in the subsequent process was not torn by the step of the insulating film 11. The substrate 5 was a transparent glass substrate similar to the substrate 4.

  Further, an ITO film having a thickness of 140 nm was formed on the surface of the substrate 5 on which the insulating film 11 was formed by sputtering, and an aluminum film serving as a light reflective electrode was further formed by sputtering to a thickness of 200 nm. Next, the obtained aluminum film is photolithographed so that the aluminum film remains only in the reflective display portion 9 (that is, the portion where the photosensitive resin is left when patterning the photosensitive resin to form the insulating film 11). The reflective film 8 was formed by patterning by lithography and dry etching. Further, the ITO film under the reflective film 8 was etched using photolithography to produce an electrode 7 (transparent electrode) having a predetermined pattern.

  Next, an alignment film 3 was formed on the surface of the substrate 5 on which the electrodes 7 and the reflective film 8 were formed by the same method as the alignment film 2 of the electrode substrate 101 that was the observer side substrate. Thereafter, the alignment film 3 was subjected to an alignment process by rubbing to produce an electrode substrate 102.

  Among the electrode substrates 101 and 102 manufactured as described above, a seal resin (not shown) as an encapsulating sealant is arranged around one electrode substrate, and the alignment film forming surface of the other electrode substrate Then, spherical plastic spacers having a diameter of 4.5 μm were sprayed, and as shown in FIG. 1, the sealing resin was cured under pressure with the electrode surfaces facing each other, to prepare a liquid crystal cell for liquid crystal injection. When the thickness of the liquid crystal injection gap (that is, the thickness of the liquid crystal layer 1) in the reflective display unit 9 and the transmissive display unit 10 of the liquid crystal cell for liquid crystal injection was measured by measuring the reflected light spectrum, It was 4.5 μm and 7.5 μm in the transmissive display unit 10.

  Furthermore, when the liquid crystal composition formed by mixing the dichroic dye 12 into the liquid crystal having a negative dielectric anisotropy is introduced into the liquid crystal cell for liquid crystal injection, the concentration of the dichroic dye 12 is determined by the reflection display unit. The density was adjusted so that a sufficient contrast ratio was obtained between 9 and the transmissive display unit 10. Further, a chiral additive that imparts twist to the alignment of the liquid crystal is added to the liquid crystal composition, and the alignment treatment applied to the alignment films 2 and 3 and the liquid crystal between the upper and lower electrode substrates 101 and 102 of the liquid crystal layer 1 are performed. The twist of orientation was set to be the same between the reflective display unit 9 and the transmissive display unit 10 in a voltage application state used for dark display. Further, the liquid crystal composition was introduced into the liquid crystal cell for liquid crystal injection by a vacuum injection method to produce a liquid crystal display device.

  When voltage was applied to the liquid crystal layer 1 while measuring the reflectance of the reflective display unit 9 and the transmittance of the transmissive display unit 10 in the obtained liquid crystal display device with a microscope, the display characteristics shown in FIG. 2 were obtained. The voltage applied to the liquid crystal layer 1 is a rectangular wave whose polarity is reversed every 17 msec. In FIG. 2, the horizontal axis indicates the effective value of the applied voltage, and the vertical axis indicates the brightness (reflectance or transmittance). . In the figure, a curve 111 shows the voltage dependency of the reflectance of the reflective display unit 9, and a curve 112 shows the voltage dependency of the transmittance of the transmissive display unit 10.

  As shown by the curves 111 and 112, in the liquid crystal display device described above, the brightness (reflectance or transmittance) in the reflective display unit 9 and the transmissive display unit 10 both decreases with the application of voltage. When the applied voltage is 1.8 V, the reflectance of the reflective display unit 9 is 55%, the transmittance of the transmissive display unit 10 is 52%, and when the applied voltage is 5 V, the reflective display unit 9 The transmittance of the transmissive display unit 10 was 10%.

  That is, according to the above-described liquid crystal display device, both the reflective display unit 9 and the transmissive display unit 10 have a high value of bright display exceeding 50% and a contrast ratio of about 5. There was a display with excellent visibility.

[Comparative Example 1]
Here, the comparative example of said Example 1 is shown. In Comparative Example 1, in the liquid crystal display device using the GH method shown in Example 1, except that the liquid crystal layer thickness in the reflective display unit 9 and the liquid crystal layer thickness in the transmissive display unit 10 are designed to be the same, A comparative liquid crystal display device was produced in accordance with the method for producing the liquid crystal display device shown in Example 1.

  More specifically, in this comparative example, the insulating film 11 as produced on the substrate 5 of Example 1 is not produced, and the liquid crystal layer thickness in the reflective display unit 9 and the liquid crystal layer thickness in the transmissive display unit 10 are different. Both produced liquid crystal display devices of 4.5 μm. That is, the upper and lower electrode substrates facing each other with the liquid crystal layer 1 interposed therebetween produce a smooth liquid crystal injection liquid crystal cell with the reflective display portion 9 and the transmissive display portion 10, and this liquid crystal injection liquid crystal cell is implemented. A liquid crystal display device was produced by introducing a liquid crystal composition in which the same dichroic dye 12 and a chiral additive as in Example 1 were mixed.

  FIG. 3 shows display characteristics obtained by measuring the reflectance of the reflective display section 9 and the transmittance of the transmissive display section 10 in the obtained liquid crystal display device by the same method as in the first embodiment.

[Comparative Example 2]
In Comparative Example 2, a liquid crystal composition having a higher concentration of the dichroic dye 12 than in Comparative Example 1 is introduced into the same liquid crystal cell as in Comparative Example 1, and the brightness and contrast ratio of the transmissive display unit 10 are optimal. A liquid crystal display device set so as to be prepared was prepared.

  The display characteristics obtained by measuring the reflectance of the reflective display unit 9 and the transmittance of the transmissive display unit 10 in the obtained liquid crystal display device by the same method as in Example 1 are combined with the results of Comparative Example 1. As shown in FIG.

  In FIG. 3, the horizontal axis indicates the effective value of the applied voltage, and the vertical axis indicates the brightness (reflectance or transmittance). Further, in the same figure, a curve 121 indicates the voltage dependency of the reflectance of the reflective display unit 9 of Comparative Example 1, and a curve 122 indicates the voltage dependency of the transmittance of the transmissive display unit 10 of Comparative Example 1. A curve 123 indicates the voltage dependency of the reflectance of the reflective display unit 9 of Comparative Example 2, and a curve 124 indicates the voltage dependency of the transmittance of the transmissive display unit 10 of Comparative Example 2.

  As shown by the curves 121 and 122, in the liquid crystal display device obtained in Comparative Example 1, both the brightness (reflectance or transmittance) in the reflective display unit 9 and the transmissive display unit 10 are accompanied by the application of voltage. Although it is lowered, the reflectance of the reflective display unit 9 when the applied voltage is 1.8 V was 51%, whereas the transmittance of the transmissive display unit 10 was 66%, and the applied voltage was The reflectance of the reflective display unit 9 at 5 V was 11%, and the transmittance of the transmissive display unit 10 was 22%.

  That is, according to the liquid crystal display device obtained in Comparative Example 1, the reflective display unit 9 has a high brightness exceeding 50% and a contrast ratio of about 5, but the transmissive display unit 10 has the transmission. Since the liquid crystal layer thickness in the display unit 10 is the same as the liquid crystal layer thickness in the reflective display unit 9, the brightness of the liquid crystal layer 1 is high, but the contrast ratio is as low as about 3 and the display quality is low.

  Further, as shown by the curve 123 and the curve 124, in the liquid crystal display device obtained in Comparative Example 2, the brightness (reflectance or transmittance) in the reflective display unit 9 and the transmissive display unit 10 are both reduced in voltage. Although it decreases, the reflectance of the reflective display unit 9 when the applied voltage is 1.8 V was 29%, whereas the transmittance of the transmissive display unit 10 was 51%. When the voltage was 5 V, the reflectance of the reflective display unit 9 was 3%, and the transmittance of the transmissive display unit 10 was 10%.

  That is, according to the liquid crystal display device obtained in Comparative Example 2, the transmissive display unit 10 has a high brightness exceeding 50% and a contrast ratio of about 5, but the reflective display unit 9 has the reflection. Since the liquid crystal layer thickness in the display unit 9 is the same as the liquid crystal layer thickness in the transmissive display unit 10, the contrast ratio is as high as about 10, but the brightness is less than 30%, resulting in a dark display.

  As is clear from the comparison between Example 1 and Comparative Examples 1 and 2, in the GH liquid crystal display device, the contrast ratio of the transmissive display unit 10 is equal to or higher than the contrast ratio of the reflective display unit 9. It was found effective to set the layer thickness of the liquid crystal layer 1 of the transmissive display unit 10 to be larger than the layer thickness of the liquid crystal layer 1 of the reflective display unit 9.

[Embodiment 2]
In the first embodiment, the liquid crystal display device using the GH mode has been described. However, as the liquid crystal display mode according to the present invention, in addition to the GH mode, as shown in FIG. A method of sandwiching the plates 14 and 15 and utilizing the retardation and rotation of the liquid crystal layer 1 (hereinafter collectively referred to as polarization conversion action) for display may be employed.

  Therefore, in the present embodiment, a liquid crystal display device using the polarization conversion action for display will be described below mainly with reference to FIG. For convenience of explanation, components having the same functions as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 4 is a cross-sectional view of a main part of the liquid crystal display device according to the present embodiment. The liquid crystal display device shown in FIG. 4 includes a liquid crystal cell 200 (liquid crystal display element) and, if necessary, the backlight 13 (illumination device). The liquid crystal cell 200 and the backlight 13 are arranged in the order of the liquid crystal cell 200 and the backlight 13 from the observer (user) side.

  As shown in FIG. 4, the liquid crystal cell 200 includes an electrode substrate 201 (first electrode) having an alignment film 2 on the side where the liquid crystal layer 1 is in contact with the liquid crystal layer 1 (interface on the first substrate in contact with the liquid crystal layer 1). 1) and an electrode substrate 202 (second substrate) provided with an alignment film 3 on the side in contact with the liquid crystal layer 1 (interface on the second substrate in contact with the liquid crystal layer 1). The phase difference compensation plate 16 and the polarizing plate 14 are provided on the outside of the substrate 201 (that is, the side opposite to the surface facing the electrode substrate 202), and the outside of the electrode substrate 202 (that is, the surface facing the electrode substrate 201). The phase difference compensation plate 17 and the polarizing plate 15 are provided on the opposite side. The phase difference compensation plates 16 and 17 are provided and used as necessary.

  As the retardation compensation plates 16 and 17 used as necessary in the present invention, various retardation compensation plates such as a stretched polymer film, a liquid crystal alignment fixed polymer film, and a liquid crystalline polymer film are used. Can do. The optical action is for preventing coloring often seen when the phase difference compensation plates 16 and 17 are not used, changing the lightness dependency on the potential difference between the electrodes 6 and 7, and changing the display viewing angle. Used for.

  The electrode substrate 201 is provided with an electrode 6 for applying a voltage to the liquid crystal layer 1 on a substrate 4 made of a light-transmitting glass substrate or the like, and a rubbing process is performed so as to cover the electrode 6. An alignment film 2 having been subjected to is formed.

  On the other hand, the electrode substrate 202 provided opposite to the electrode substrate 201 with the liquid crystal layer 1 interposed therebetween is provided with an insulating film 11 on the translucent substrate 5 in order to apply a voltage to the liquid crystal layer 1. Thus, an electrode 7 as a counter electrode facing the electrode 6 is formed. However, in the liquid crystal display device shown in FIG. 4, the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10 are electrically insulated so that voltages are applied separately from outside the liquid crystal cell. Have. A reflective film 8 is formed in a region corresponding to the reflective display portion 9 in the electrode substrate 202, and an alignment film 3 subjected to rubbing treatment is formed so as to cover these electrodes 7 and the reflective film 8. Has been. The insulating film 11 is formed so that the film thickness of the region corresponding to the transmissive display unit 10 in the insulating film 11 is smaller than the film thickness of the region corresponding to the reflective display unit 9.

  As shown in FIG. 4, the electrode substrates 201 and 202 are arranged so that the alignment film 2 and the alignment film 3 face each other, and are bonded together using an encapsulating sealant or the like, and a liquid crystal composition is introduced into the gap. As a result, the liquid crystal layer 1 is formed.

  In the liquid crystal display device, in the bright display, the liquid crystal layer 1 made of the liquid crystal composition described above has a structure in which the reflective display unit 9 and the transmissive display unit 10 communicate with each other. When the liquid crystal of the liquid crystal layer 1 is parallel-aligned as shown in the reflective display portion 9b and the transmissive display portion 10b in FIG. It becomes. On the other hand, as shown in the reflective display unit 9a and the transmissive display unit 10a, when the liquid crystal of the liquid crystal layer 1 is vertically aligned, the polarization conversion action is weak and a bright display is obtained.

  Therefore, the alignment change in the reflective display portions 9a and 9b and the transmissive display portions 10a and 10b is caused by a straight line formed by the polarizing plate 14 on the display surface side and the polarizing plate 15 on the backlight 13 side, which is disposed with the liquid crystal layer 1 interposed therebetween. By using the polarization selective transmission action as a display light intensity change for display, bright display and dark display are possible. As described above, in this case, in order to compensate the wavelength dependence of the refractive index difference of the liquid crystal layer 1, or to change the voltage dependence of the brightness modulated by the liquid crystal layer 1 as necessary, or In order to change the viewing angle of display, phase difference compensators 16 and 17 as shown in FIG. 4 may be used.

  Even when the optical anisotropy is used for display as described above, the initial alignment state of the liquid crystal is not particularly limited. For example, the liquid crystal layer 1 in a state in which no voltage is applied is parallel to the display surface. It may be in a state of being oriented in the vertical direction, or in a state of being vertically oriented. In the former case (that is, when the liquid crystal alignment in a state where no voltage is applied is a parallel alignment), a liquid crystal having a positive dielectric anisotropy can be used as the liquid crystal. On the other hand, in the latter case (that is, when the liquid crystal alignment in a state where no voltage is applied is vertical alignment), a liquid crystal having a negative dielectric anisotropy can be used as the liquid crystal.

  As described above, even when the optical anisotropy is used for display, the initial alignment state of the liquid crystal is not particularly limited, but a liquid crystal layer thickness suitable for the form of liquid crystal alignment to be used can be obtained. It is effective to adjust the film thickness of the insulating film 11.

  In order to realize dark display on the reflective display unit 9, first, light that has been linearly polarized by the polarizing plate 14 is prepared. Then, if necessary, the polarization state is changed by the phase difference compensation plate 16, and the polarization state is further changed in the liquid crystal layer 1 of the reflective display unit 9 whose layer thickness is set to be thinner than that of the transmissive display unit 10. At this time, a necessary condition for an ideal dark display is that the polarization state on the reflection film 8 is circularly polarized light which can be turned to the left or right as a result. Further, a necessary condition for realizing an ideal bright display on the same reflective display unit 9 is that the polarization state on the reflective film 8 is linearly polarized light. If the liquid crystal alignment can be electrically controlled between the dark display and the bright display, the display can be switched.

  That is, when realizing dark display, the phase difference that the liquid crystal layer 1 gives to the light before the light incident on the liquid crystal layer 1 reaches the reflection film 8 (the phase difference of the display light on the reflection film 8). The phase difference (the phase difference of the display light on the reflection film 8) that the liquid crystal layer 1 gives to the light before the light incident on the liquid crystal layer 1 reaches the reflection film 8 when realizing bright display. There is a difference of substantially a quarter wavelength (approximately 90 degrees) between them, and the liquid crystal alignment that realizes the difference is, for example, electrically controllable, that is, circularly polarized light in dark display and linearly polarized light in bright display. It suffices if it can be controlled between. At this time, the polarization direction of the linearly polarized light on the reflective film 8 realizing the bright display may be an arbitrary direction.

  In the transmissive display unit 10, the polarization state of the light linearly polarized by the polarizing plate 15 is changed by the retardation compensation plate 17 as necessary, and then the layer thickness is set to be thicker than that of the reflective display unit 9. The liquid crystal layer 1 is changed, and if necessary, it is changed by the phase difference compensation plate 16 and emitted from the polarizing plate 14 to display.

  In this case, what is used for display is a change in polarization state immediately before entering the polarizing plate 14. Therefore, in the case of performing bright display, the polarization state immediately before entering the polarizing plate 14 may be adjusted so as to be linearly polarized light having the oscillation direction of the transmission axis direction of the polarizing plate 14, and dark display is performed. In this case, the polarization state immediately before entering the polarizing plate 14 may be adjusted so as to be linearly polarized light having the vibration plane of the absorption axis direction of the polarizing plate 14.

  That is, the phase difference given to the light passing through the liquid crystal layer 1 of the transmissive display unit 10 when performing bright display (the phase difference of display light emitted from the liquid crystal layer 1) and the transmissive display unit 10 when performing dark display. The alignment of the liquid crystal layer 1 so that the difference from the phase difference given to the light passing through the liquid crystal layer 1 (the phase difference of the display light emitted from the liquid crystal layer 1) is substantially ½ wavelength (approximately 180 degrees). The display can be switched by electrically controlling the change in voltage by applying a voltage.

  Here, the half wavelength phase control corresponds to controlling the polarization direction of linearly polarized light incident on the polarizing plate 14 from the liquid crystal layer 1 side, and is based on retardation in which the principal axes of the refractive index are uniformly aligned in parallel. Polarization including not only the control of the phase difference but also the optical rotation phenomenon in which the principal axis of the refractive index of the liquid crystal layer 1 is twisted with the twist of the liquid crystal alignment, and the polarization direction of the linearly polarized light changes with the change of the twist of the alignment. It is a conversion action. The polarization conversion action of the liquid crystal layer 1 that realizes this is a polarization conversion action between general orthogonal polarization states in consideration of application of the phase difference compensation plate 16 and the phase difference compensation plate 17.

  The liquid crystal alignment that enables the polarization conversion action to realize the polarization state control (light phase control) as described above is parallel to the substrates 4 and 5 (parallel to the display surface) and uniform parallel alignment (homogeneous). Orientation), which is parallel to the substrates 4 and 5 (parallel to the display surface) and twisted between the substrates 4 and 5 (between the upper and lower substrates facing each other with the liquid crystal layer 1 interposed therebetween). It may also be a vertical alignment (homeotropic alignment) perpendicular to the substrates 4 and 5 (perpendicular to the display surface). Furthermore, hybrid alignment or the like in which one interface of the liquid crystal layer 1 is parallel alignment and the other is vertical alignment can be used.

In this case, specifically, the twist orientation is set to 60 degrees or more and 100 degrees or less between the substrates 4 and 5, or is set to 0 degrees or more and 40 degrees or less. desirable.
This is because the conditions suitable for the reflective display unit 9 and the conditions suitable for the transmissive display unit 10 can be made compatible without changing the rubbing direction between the transmissive display unit 10 and the reflective display unit 9. Because it becomes.

  When mass-producing liquid crystal display devices, the most preferable optical design of the liquid crystal layer 1 is that the display brightness (reflectance or transmittance) increases monotonically between the upper and lower limits of the drive voltage range applied to the liquid crystal layer 1. Or it is a design which changes so that it may decrease monotonously.

  In consideration of the above driving conditions, the simplest optical design of the liquid crystal layer 1 is between a liquid crystal aligned substantially perpendicular to the display surface and a liquid crystal aligned substantially parallel to the display surface. The design is such that the electro-optic characteristic is achieved such that the display is controlled so that the display brightness monotonously increases or decreases monotonously.

  In this case, particularly when a liquid crystal alignment parallel to the display surface is realized as a liquid crystal alignment with no voltage applied using a parallel alignment film, there are conditions suitable for reflective display and conditions suitable for transmissive display. It exists clearly. Therefore, this condition was obtained by calculation using the so-called Jones matrix method, and an appropriate range of the twist angle was obtained.

  As a result, it has been clarified that the twist angle needs to be set to 0 degree or more and 100 degrees or less in order to obtain a good display by the reflective display.

  In other words, first, the inventors of the present application, in the liquid crystal layer 1 that realizes a good display in the reflective display, have a liquid crystal alignment having a polarization converting action (when a parallel alignment film is used, a voltage is not applied substantially. In order to evaluate the efficiency of converting circularly polarized light into linearly polarized light in the liquid crystal alignment), the reflectance when circularly polarized light is incident on the liquid crystal layer 1 is calculated by the above calculation method. Sought by. In the calculation, light is incident on the liquid crystal cell 200 in the order of the polarizing plate 14, the retardation compensation plate 16 that gives a phase difference of 90 degrees, the liquid crystal layer 1, and the reflective film 8. The reflectance of the light that propagated up to the plate 14 and was emitted was determined.

  As a result, by adjusting the product (Δn · d) of the refractive index difference (Δn) of the liquid crystal of the liquid crystal layer 1 and the liquid crystal layer thickness (d) for each twist angle of the liquid crystal layer 1, the twist angle is 0 degree or more. It was revealed that circularly polarized light can be converted into completely linearly polarized light within a range of 70 degrees or less. In addition, it has been found that, within the range from 70 degrees to 100 degrees, circularly polarized light cannot be completely linearly polarized, but good display is possible. When the maximum value at a visible wavelength of the reflectance up to 70 degrees in the twist angle is 100%, the twist at a specific wavelength is adjusted by adjusting Δn · d of the liquid crystal layer 1 for each twist angle. When the angle is 80 degrees, the reflectivity is 97%, when the twist angle is 90 degrees, the reflectivity is 83%, and when the twist angle is 100 degrees, the reflectivity is 72%, and a good reflectivity can be obtained. However, when the twist angle exceeds 100 degrees, for example, the reflectivity is 54% when the twist angle is 110 degrees, and the reflectivity is 37% when the twist angle is 120 degrees, so that circularly polarized light is efficiently polarized into linearly polarized light. Is impossible. That is, in the liquid crystal layer 1 in the reflective display unit 9, it is necessary to set the twist angle within a range of 0 ° to 100 °.

  In the above description, circularly polarized light is used for calculation in order to evaluate the polarization conversion action of the liquid crystal layer 1 in the reflective display unit 9. However, in actual display, the liquid crystal layer 1 of the reflective display unit 9 is not necessarily circular. There is no need to make polarized light incident. Even when the liquid crystal layer 1 is designed as described above and linearly polarized light is made incident on the liquid crystal layer 1, a good display can be obtained by the reflective display unit 9.

  On the other hand, in order to obtain a good display in the transmissive display unit 10, the liquid crystal orientation is an orientation with a small twist angle (0 degree or more and 40 degrees or less) or a large twist angle (60 degrees or more, 110 degrees). Degree or less).

  The polarization conversion action necessary for obtaining a good display in the transmissive display unit 10 includes the basic optical action (first condition), the basic optical action (first condition), and the reflective display part 9. It is necessary to satisfy the realistic optical action (second condition) determined by the relationship of

  The reason for this is, for example, in the case of the first condition, in the liquid crystal alignment having a polarization converting action (when a parallel alignment film is used, the alignment is substantially equal to the alignment when no voltage is applied). In the liquid crystal layer 1 in FIG. 10, a certain polarized light (linearly polarized light, circularly polarized light, or elliptically polarized light having a designated polarization state) is efficiently polarized perpendicularly (in the case of linearly polarized light, an oscillating electric field of light). Linearly polarized light whose planes are orthogonal, circularly polarized light with circular rotation reversed in the case of circularly polarized light, elliptical polarized light with ellipticity of the same ellipticity with the elliptical main axis orientation orthogonal, and elliptically polarized light with reversed rotational direction) This is because it requires an action to convert to.

  Therefore, the inventors of the present application have obtained the polarization conversion action by the above calculation method (Jones matrix method) in order to evaluate the above action as a necessary property of the transmissive display unit 10. Contrary to the above, it has become clear that there is no particular limitation.

  In the present invention, the second condition occurs because the reflective display unit 9 and the transmissive display unit 10 use a common optical film (polarizing plate 14 and retardation compensation plate 16) on the display surface side. It is a constraint. The optical films in the reflective display unit 9 and the transmissive display unit 10 are set so as to perform reflective display satisfactorily. A different optical film can be set on the surface opposite to the display surface of the liquid crystal display device. This optical film can be used to display the transmissive display unit 10 as an optical film on the display surface side. 14 and the retardation compensation plate 16 and the liquid crystal layer 1 on the transmissive display unit 10 side are preferably set so as to be favorable. In order to perform such a setting, the polarization conversion action of the liquid crystal layer 1 in the transmissive display unit 10 can not only simply satisfy the first condition, but also convert circularly polarized light into reverse circularly polarized light. Alternatively, it is important that the linearly polarized light can be satisfactorily converted into orthogonal linearly polarized light.

  Therefore, in order to evaluate a specific condition that satisfies the second condition for the liquid crystal layer 1 in the transmissive display unit 10, when circularly polarized light is incident on the liquid crystal layer 1, the light that becomes reverse circularly polarized light is reflected. The strength was determined by the above calculation method. The calculation is based on the assumption that light is a polarizing plate 15 as a first polarizing plate, a phase difference compensating plate 17 as a first phase compensating plate that gives a phase difference of 90 degrees, a liquid crystal layer 1, a phase difference of 90 degrees. A phase difference compensation plate 16 as a second phase difference compensation plate having a slow axis perpendicular to the first phase difference compensation plate for providing the first retardation plate, and a polarizing plate as a second polarizing plate perpendicular to the first polarizing plate The transmittance when propagating in the order of 14 was obtained.

  As a result, when the present inventors adjust Δn · d of the liquid crystal layer 1 for each twist angle, when the twist angle is in the range of 0 degrees or more and 40 degrees or less, the circularly polarized light becomes the reverse circularly polarized light. We found that it was converted well. Specifically, when the transmittance of light at a visible wavelength when the twist angle is 0 degree is 100%, the transmittance of light when the twist angle is 30 degrees is 88.6% and the twist angle is 40 degrees. When the twist angle is 50 degrees, the light transmittance is 80.8%, when the twist angle is 50 degrees, the light transmittance is 72.0%, and when the twist angle is 60 degrees, the light transmittance is 62.4%. When the polarization conversion action for converting the polarized light into the reverse circularly polarized light is evaluated by the transmittance, the transmittance decreases as the twist angle increases. For this reason, the conclusion that the upper limit of the twist angle is appropriately set to about 40 degrees was obtained from the above results.

  On the other hand, the twist angle of the transmissive display unit 10 that efficiently converts linearly polarized light into orthogonal linearly polarized light can be set to any twist angle of 0 degree or more when the wavelength of light is limited to one wavelength. Thus, a sufficiently efficient transmittance can be realized. However, in order to obtain a high transmittance in a wide visible wavelength region, there is an optimum value for the twist angle. Specifically, when the twist angle is changed and Δn · d of the liquid crystal layer 1 is adjusted so that the maximum transmittance is 550 nm, which is the center wavelength in the visible wavelength range, and the transmittance at 550 nm is 100%. In addition, the wavelength width excluding the upper limit and lower limit of the wavelength at which a transmittance of 90% or more was obtained was obtained. Note that the transmittance is calculated when light passes through the polarizing plate 15 as the first polarizing plate, the liquid crystal layer 1, and the polarizing plate 14 as the second polarizing plate orthogonal to the first polarizing plate. The liquid crystal alignment at the center in the layer thickness direction of the liquid crystal layer 1 is arranged to form an angle of 45 degrees with the transmission axis of the polarizing plates 14 and 15, and the transmittance at that time is obtained.

  As a result, the wavelength width (wavelength range) when the twist angle is 0 degree is 230 nm, the wavelength width when the twist angle is 10 degrees is 235 nm, the wavelength width when the twist angle is 20 degrees is 240 nm, and the twist angle is 30. When the twist angle is 40 degrees, the wavelength width is 245 nm, when the twist angle is 40 degrees, the wavelength width is 250 nm, when the twist angle is 50 degrees, the wavelength width is 255 nm, and when the twist angle is 60 degrees, the wavelength width is 265 nm. When the twist angle is 80 degrees, the wavelength width is 280 nm, when the twist angle is 80 degrees, the wavelength width is 310 nm, when the twist angle is 90 degrees, the wavelength width is 330 nm, and when the twist angle is 100 degrees, the wavelength width is 305 nm, The wavelength width when the twist angle was 110 degrees was 255 nm, and the wavelength width when the twist angle was 120 degrees was 210 nm.

  Based on the above considerations, high transmittance is realized in a wide wavelength range (wavelength range) within a twist angle range of 60 degrees or more and 110 degrees or less, a good polarization conversion action is realized, and a good display is possible. It turned out that it becomes. Therefore, the twist angle of the liquid crystal of the transmissive display unit 10 satisfying the second condition is within the range of 0 degree or more and 40 degrees or less from the polarization conversion action for circularly polarized light and the polarization conversion action for linearly polarized light, or It is limited within the range of 60 degrees or more and 110 degrees or less.

  As described above, the reflective display unit 9 has a range of 0 ° to 100 °, the transmissive display unit 10 has a range of 0 ° to 40 °, or 60 ° to 110 °. It became clear that the twist angle within the range gives a good indication. That is, as an example of the embodiment of the present invention, the twist angle for obtaining a good display in both the reflective display unit 9 and the transmissive display unit 10 is in the range of 0 degrees or more and 40 degrees or less, or 60 The range of not less than 100 degrees and not more than 100 degrees is appropriate.

  In the examples shown below, in the examples (Examples 2 to 9 and Example 11) in which the twist angle of the liquid crystal layer 1 in the reflective display unit 9 and the transmissive display unit 10 is the same, the twist angle is 0. A typical example using circularly polarized light at a degree is Example 11 (liquid crystal alignment is vertical alignment), and a typical example using linearly polarized light with a twist angle of 0 degree is Example 3 (phase difference compensator). It is adjusted so that a bright display is better. A typical example in which linearly polarized light is used at a twist angle of around 70 degrees is Example 5 (adjusted so that a good bright display is obtained by a phase difference compensator).

  According to the above-described examination, the twist angle of the liquid crystal layer 1 for obtaining a good display in both the reflective display unit 9 and the transmissive display unit 10 is in the range of 0 degrees or more and 40 degrees or less, or 60 degrees. As described above, it is within the range of 100 degrees or less.

  In the above description, the magnitude of the twist angle has been described only with respect to the positive sign, but the same argument is valid for the negative sign (which is twisted in the opposite direction) with the same absolute value. Needless to say.

  In any case where the twist angle is set to be small, the change in the polarization state becomes a function of the product (Δn · d) of the refractive index difference (Δn) and the liquid crystal layer thickness (d), and the reflection display unit 9, the incident light travels back and forth through the liquid crystal layer 1, and the transmissive display portion 10 passes the liquid crystal layer 1 only once. Therefore, the liquid crystal layer thickness in the transmissive display portion 10 is larger than the liquid crystal layer thickness in the reflective display portion 9. Therefore, it is desirable to set it thick.

  Even in a TN liquid crystal display device using ordinary optical rotation, when the liquid crystal layer is thin, the optical rotation and the change in polarization state due to retardation are indistinguishable, and in general, elliptically polarized light is used for display. Therefore, it goes without saying that the optical rotation used in the TN liquid crystal display device can be used for bright display and dark display using the polarization conversion action described above. The polarization conversion action in the present invention includes modulation of transmitted light intensity by these optical rotations.

  Furthermore, in the polarization conversion action, the change in the liquid crystal alignment that can change the polarization state is only to control whether the alignment state of the liquid crystal is parallel or perpendicular to the substrates 4 and 5 as described above. First, the liquid crystal, such as surface-stabilized ferroelectric liquid crystal and anti-ferroelectric liquid crystal, changes only in the orientation direction while maintaining the orientation direction almost parallel to the substrates 4 and 5, or nematic liquid crystal. Also included are those that change the orientation orientation while changing the electrode structure and maintaining the orientation direction of the liquid crystal in a plane parallel to the display surface.

  In the above liquid crystal display device, the installation orientation (sticking orientation) of the polarizing plates 14 and 15 can be set as appropriate. For example, if the installation orientation of the polarizing plate 14 is set in accordance with the reflective display unit 9, the same polarizing plate 14 inevitably acts on the display light transmitted through the transmissive display unit 10. The installation direction of the polarizing plate 15 may be determined in accordance with the installation direction.

  As described above, when the liquid crystal alignment having no twist is used for display, when the reflective display unit 9 displays a dark display, for example, the transmissive display unit 10 similarly displays a dark display, for example. However, for example, when the installation orientation of the polarizing plate 15 is changed and the installation orientation of the polarizing plate 15 is changed by 90 degrees, display inversion occurs between the reflective display unit 9 and the transmissive display unit 10. That is, as it is, a good display cannot be obtained. Therefore, in order to prevent such inversion of the display, the installation orientation of the polarizing plate 15 is returned to the original, or an independent electrode is provided to each of the reflective display unit 9 and the transmissive display unit 10 to electrically The driving itself may be reversed by only one of the reflective display unit 9 and the transmissive display unit 10 to match the brightness of the display.

  Next, the display principle of the reflective display unit 9 and the transmissive display unit 10 in the liquid crystal display device shown in FIG. 4 will be described in more detail.

  First, the display principle of the reflective display unit 9 will be described below. In order to simplify the explanation, in the following explanation, the phase difference compensation plates 16 and 17 are not used, and the liquid crystal orientation of the liquid crystal layer 1 is twisted in the reflective display portion 9b and the transmissive display portion 10b. Make it not exist. Further, when light having a wavelength of 550 nm passes through the liquid crystal layer 1 only once, reflection is performed so that the reflective display portion 9b and the transmissive display portion 10b have a phase difference of ¼ wavelength and ½ wavelength, respectively. It is assumed that the layer thicknesses of the display unit 9 and the transmissive display unit 10 are adjusted, the liquid crystal composition has a positive dielectric anisotropy, and the liquid crystal alignment when no voltage is applied is approximately relative to the substrates 4 and 5. It is assumed that the orientation direction is 45 degrees with respect to the absorption axis direction of the polarizing plate 14.

  In this case, the liquid crystal alignment in the reflective display unit 9 and the transmissive display unit 10 in the state where no voltage is applied is the liquid crystal alignment shown in the reflective display unit 9b and the transmissive display unit 10b, and the reflective display unit 9 and The liquid crystal alignment in the transmissive display unit 10 is the liquid crystal alignment shown in the reflective display unit 9a and the transmissive display unit 10a.

  In the reflective display portion 9b, a quarter wavelength condition is established for the product (Δn · d) of the refractive index difference (Δn) of the liquid crystal composition and the liquid crystal layer thickness (d). For this reason, ambient light becomes linearly polarized light at the polarizing plate 14 when incident, and becomes circularly polarized light when reaching the reflecting film 8 due to the retardation of the liquid crystal layer 1. At this time, the traveling direction of the incident light is reversed by the reflection film 8, and the circularly polarized light preserves the rotation direction of the oscillating electric field and only the traveling direction is reversed. That is, the left and right are circularly polarized light. This circularly polarized light passes through the liquid crystal layer 1 of the reflective display portion 9b again and becomes linearly polarized light parallel to the absorption axis direction of the polarizing plate 14, and is absorbed by the polarizing plate 14, resulting in dark display.

  At this time, in the transmissive display portion 10b, the product of the refractive index difference (Δn) of the liquid crystal composition and the liquid crystal layer thickness (d) (Δn · d) satisfies the ½ wavelength condition. For this reason, the liquid crystal layer 1 has an effect of converting the orientation of the vibration plane of the incident linearly polarized light into line symmetry with respect to the liquid crystal alignment direction. Accordingly, the absorption axis direction of the polarizing plate 15 on the light incident side to the transmissive display portion 10b is subjected to the above-described action of the liquid crystal layer 1, and the light passing through the polarizing plate 14 is absorbed by the polarizing plate 14 to display darkly. So that the transmission axis direction of the polarizing plate 14 and the polarizing plate 15 is parallel.

  As described above, when the polarizing plate 14 and the polarizing plate 15 are arranged so that their transmission axis directions are parallel and the liquid crystal alignment forms an angle of 45 degrees from the transmission axis direction, It was found that both the display portions 10b are darkly displayed.

  Next, by applying a potential difference to the electrodes 6 and 7 from the voltage non-application state (the initial alignment state of the liquid crystal) shown in the reflective display portion 9b and the transmissive display portion 10b, the alignment state of the liquid crystal is changed to the reflective display portion 9a. As will be described in the transmissive display section 10a, the operation when it is changed substantially perpendicularly to the display surface will be described below.

  In this case, in the reflective display unit 9a, the ambient light becomes linearly polarized light by the polarizing plate 14, and the liquid crystal layer 1 has no retardation with respect to the linearly polarized light. After reaching 8 and the traveling direction is further reversed, it passes through the liquid crystal layer 1 again, and is emitted from the polarizing plate 14 while maintaining the direction of linearly polarized light orthogonal to the absorption axis direction of the polarizing plate 14.

  Also in the transmissive display unit 10a, similarly to the reflective display unit 9a, the incident light becomes linearly polarized light by the polarizing plate 15, and passes through the polarizing plate 14 while maintaining the direction of the linearly polarized light.

  When utilizing the polarization conversion action due to optical anisotropy as described above for display, the amount of this polarization conversion action is, for example, when the liquid crystal is aligned in parallel and no voltage is applied to the liquid crystal layer 1. It is determined by the twist angle of the alignment of the liquid crystal layer 1 and the product (Δn · d) of the liquid crystal layer thickness (d) and the refractive index difference (Δn) of the liquid crystal composition. For this reason, the transmissive display unit 10 having a liquid crystal layer thickness thicker than that of the reflective display unit 9 as in the present invention reduces the display brightness and contrast ratio in a liquid crystal display device that uses transmitted light and reflected light for display. It is effective to make both the reflective display unit 9 and the transmissive display unit 10 compatible. The twist angle may be different between the reflective display unit 9 and the transmissive display unit 10.

  In addition, when the liquid crystal display device includes the phase difference compensation plates 16 and 17, sufficient brightness and contrast ratio can be ensured for light having a plurality of wavelengths in the visible light region. Even better display can be realized.

  Even if the liquid crystal composition and orientation of the liquid crystal layer 1 are the same as described above, the change in display can be reversed by the action of the retardation compensation plates 16 and 17. That is, for example, if quarter-wave plates are used as the phase difference compensation plates 16 and 17, the ambient light becomes circularly polarized when entering the liquid crystal layer 1 by the phase difference compensation plate 16 in the reflective display unit 9b. Further, due to the polarization conversion action due to the optical anisotropy of the liquid crystal layer 1, when it reaches the reflection film 8, it becomes linearly polarized light, and after the traveling direction is reversed by the reflection film 8, it is converted again into the transmission component of the polarizing plate 14. When the liquid crystal alignment changes as shown in the reflection display portion 9a, the ambient light reaches the reflection film 8 as circularly polarized light, so that the display is bright. Display.

  In the above description, the case where the display changes from the dark display to the bright display as the potential difference between the electrode 6 and the electrode 7 increases is described. However, the change in the display is limited to this. Instead, for example, as described above, the liquid crystal composition used for the liquid crystal layer 1 can be inverted by making the dielectric anisotropy negative and setting the initial alignment state of the liquid crystal to the vertical alignment.

  Here, in the case where the initial alignment state of the liquid crystal is set to the vertical alignment, there is a technical feature that the polarization conversion action of the initial alignment is not greatly influenced by the manufacturing accuracy of the liquid crystal layer thickness. Therefore, in order to take advantage of this feature, assigning the initial alignment state to the black display so that the black display that greatly affects the display quality is stable can be a highly productive means. In particular, in order to realize this, it is necessary to make the display black while the polarization conversion action of the vertically aligned liquid crystal layer 1 is almost lost, and the retardation compensation plate 16 needs a good circular polarization action. It is. In other words, it is important that the phase difference compensation plate 16 has a configuration that allows circular polarization with a wavelength as wide as possible.

  In addition, the transmissive display unit 10 is disposed so that, for example, the retardation compensation plate 17 and the retardation compensation plate 16 have a slow axis direction orthogonal to each other, and the polarizing plate 14 and the polarizing plate 15 are orthogonal to each other. In such a case, the liquid crystal alignment shown in the transmissive display unit 10b is bright and the liquid crystal alignment shown in the transmissive display unit 10a is dark.

  Even when the alignment of the liquid crystal layer 1 is either parallel alignment or vertical alignment, in the liquid crystal display device according to the present invention, when the liquid crystal layer thickness is changed between the reflective display unit 9 and the transmissive display unit 10, In order to achieve both brightness and contrast ratio in the reflective display unit 9 and the transmissive display unit 10, as described above, in the reflective display unit 9, light incident through the liquid crystal layer 1 from the display surface side again Display is performed by exiting to the display surface side through the liquid crystal layer 1, and in the transmissive display unit 10, light incident from the back side (backlight 13 side) passes through the liquid crystal layer 1 only once to the display surface side. When performing display by emitting light, the liquid crystal layer thickness in the transmissive display unit 10 is set to be thicker than the liquid crystal layer thickness in the reflective display unit 9, and as a result, it is effective to satisfy the above-described conditions.

  Hereinafter, among the liquid crystal display devices according to the present embodiment, a liquid crystal display device that uses polarizing plates 14 and 15 and uses a change in polarization state due to the polarization conversion action of the liquid crystal layer 1 for display will be described with reference to FIGS. The liquid crystal display device according to the present embodiment is not limited to the following examples, although specific examples and comparative examples will be described with reference to FIG.

[Examples 2 to 4]
In Examples 2 to 4, a liquid crystal layer thickness (in which the transmissive display unit 10 is 7.5 μm and the reflective display unit 9 is 4.5 μm) by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1 ( A liquid crystal cell for liquid crystal injection having d) was prepared. That is, also in Example 2 to Example 4, the photosensitive resin does not remain in the transmissive display unit 10, and in the reflective display unit 9, the insulating film 11 is patterned so that the photosensitive resin is formed with a layer thickness of 3 μm. By forming, the transmissive display unit 10 was set to have a thicker liquid crystal layer than the reflective display unit 9. However, in Example 2 to Example 4, as shown in FIG. 4, the electrode 7 of the reflective display unit 9 and the electrode 7 of the transmissive display unit 10 are electrically insulated, and the electrode 7 of the reflective display unit 9. And the electrode pattern was produced so that a voltage might be separately applied to the electrode 7 of the transmissive display part 10 from the outside.

  Further, in Examples 2 to 4, the liquid crystal cell for liquid crystal injection has a refractive index difference (Δn) of a liquid crystal composition not containing a chiral agent of 0.065, and positive dielectric anisotropy. The liquid crystal layer 1 was formed by introducing the liquid crystal composition having the liquid crystal composition by vacuum injection.

  Then, the phase difference compensation plates 16 and 17 and the polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell thus obtained to produce a liquid crystal display device. At this time, in the second to fourth embodiments, the phase difference compensation plate 17 is configured by two phase difference compensation plates, and the phase difference compensation plate 16 is configured by one phase difference compensation plate in the third embodiment. In Examples 2 and 4, two phase difference compensators were used. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  In Example 2, the liquid crystal alignment was homogeneous alignment, and NB (normally black) mode was used for display. In Example 3, liquid crystal alignment was homogeneous alignment, and NW (normally white) mode was used for display. In Example 4, a mixture of these (the NB mode is used for reflective display and the NW mode is used for transmissive display) is used.

  However, in Examples 2 to 4 described above, a parallel alignment film is used as the alignment films 2 and 3 so that the liquid crystal is aligned in parallel with the display surface when no voltage is applied. -The orientation process was performed with the rubbing crossing angle of 3 set to 180 degrees.

  Here, as shown in FIG. 5, the rubbing crossing angle refers to the alignment film 2 (on the electrode substrate which is the viewer side substrate among the pair of electrode substrates sandwiching the liquid crystal layer 1 in the liquid crystal cell for liquid crystal injection ( That is, with reference to the rubbing direction X which is the orientation processing direction of the orientation film 2) on the substrate 4 side, the rubbing which is the orientation processing direction of the orientation film 3 on the other electrode substrate (that is, the orientation film 3 on the substrate 5 side). The direction Y is defined as an angle measured counterclockwise.

  The alignment state of the liquid crystal molecules in the liquid crystal layer 1 sandwiched between the alignment films 2 and 3 subjected to the alignment treatment is such that the alignment property of the alignment films 2 and 3 and the twist unique to the liquid crystal are present when there is no electric field or magnetic field. It is determined by the amount of chiral additive added and the rubbing crossing angle.

  When the rubbing crossing angle is, for example, 180 degrees, the liquid crystal composition in which no chiral additive is mixed is aligned without being twisted. Further, when the chiral additive induces, for example, a twist of left twist in the liquid crystal, the liquid crystal layer 1 is aligned without being twisted until the added amount of the chiral additive reaches a certain amount. If it is exceeded, the twist orientation is 180 degrees counterclockwise (180 degree left twist orientation). When the amount of the chiral additive is further increased, a twist of an integral multiple of 180 degrees is realized as the chiral additive is increased.

  Therefore, in the present embodiment, the alignment orientation of the liquid crystal on the alignment film 3 realized by the rubbing intersection angle (180 degrees) described above is the rubbing orientation X of the alignment film 2 disposed on the electrode substrate on the upper side of the liquid crystal layer 1. Is x degrees when no chiral additive is added, and (180 + x) degrees when the chiral additive is increased and twisted 180 degrees to the left between the upper and lower electrode substrates. It will be expressed as

  In such an alignment process, the alignment films 2 and 3 are so-called parallel alignment films that align liquid crystals parallel to the alignment film surface, and no dielectric additive is mixed in. When positive nematic liquid crystal is used, when no voltage is applied, the liquid crystal molecules take an alignment state (ie, homogeneous alignment) that is substantially parallel to the upper and lower electrode substrates sandwiching the liquid crystal layer 1 and is not twisted. Is applied to the liquid crystal layer 1 in the center of the liquid crystal layer 1 in the thickness direction, and the alignment changes according to the voltage.

  Table 1 shows optical arrangements of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display devices obtained in Examples 2 to 4 (that is, the polarizing plates 14 and 15). And the orientation of the phase difference compensation plates 16 and 17 and the orientation of the liquid crystal) are shown using a common orientation standard in each example.

  The optical arrangement shown in Table 1 is the arrangement of each optical element on the display surface when the observer observes the display surface. The phase difference compensation plate 16 or the phase difference compensation plate 17 has a plurality of phase difference compensations. In the case of being constituted by plates, the phase difference compensation plates constituting the phase difference compensation plates 16 and 17 are described in the order of actual arrangement from the observer side.

  Further, since the liquid crystal layer 1 has a non-twisted orientation, the orientation direction of the entire liquid crystal layer 1 when no voltage is applied (the orientation orientation of the liquid crystal molecule major axis) is described. This is the orientation of the alignment treatment applied to the side alignment film 2.

  In addition, each azimuth represents an azimuth from a reference azimuth arbitrarily taken on the display surface in units of degrees, and retardation of each retardation compensation plate (that is, a refractive index difference and a thickness in the plane of the retardation compensation plate). Product) represents the value for monochromatic light with a wavelength of 550 nm in nm units.

  In addition, the display characteristics of the liquid crystal display devices obtained in Example 2, Example 3, and Example 4 are shown in FIGS. 6, 7, and 8, respectively. All of these display characteristics were measured by the same method as in Example 1. In each figure, the horizontal axis represents the effective value of the applied voltage, and the vertical axis represents the brightness (reflectance or transmission). Rate). Further, the transmittance of the transmissive display unit 10 to which neither of the polarizing plates 14 and 15 is attached is 100%, and the reflectance of the reflective display unit 9 before the polarizing plate 14 is attached is 100% of reflectance.

  In FIG. 6, a curve 211 indicates the voltage dependence of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 2, and a curve 212 indicates the example. 2 shows the voltage dependence of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in 2.

  As shown in FIG. 6, in Example 2, in the section where the applied voltage is 1 V to 2 V, both the reflectance and the transmittance increase as the applied voltage increases. The reflectance of the reflective display unit 9 when the applied voltage is 1 V is 3%, the transmittance of the transmissive display unit 10 is 2%, and the reflectance and transmissive display of the reflective display unit 9 when the applied voltage is 2 V. The transmittance of part 10 was 40%.

  In FIG. 7, a curve 221 indicates the voltage dependency of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 3, and the curve 222 is The voltage dependence of the transmittance | permeability of the transmissive display part 10 with respect to the voltage between the electrode 6 in the liquid crystal display device obtained in Example 3 and the electrode 7 is shown.

  As shown in FIG. 7, in Example 3, in the section where the applied voltage is 1 V to 2 V, both the reflectance and the transmittance decrease as the applied voltage increases. The reflectance of the reflective display unit 9 and the transmittance of the transmissive display unit 10 when the applied voltage is 1 V are both 40%, and the reflectance of the reflective display unit 9 when the applied voltage is 2 V is 3%. The transmittance of the display unit 10 was 2%.

  In FIG. 8, a curve 231 indicates the voltage dependency of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 4, and the curve 232 indicates The voltage dependence of the transmittance | permeability of the transmissive display part 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in Example 4 is shown.

  As shown in FIG. 8, in Example 4, in the section where the applied voltage is 1 V to 2 V, the reflectance increases with the increase of the applied voltage, while the transmittance decreases. The reflectance of the reflective display unit 9 when the applied voltage is 1 V is 3%, the transmittance of the transmissive display unit 10 is 40%, and the reflectance of the reflective display unit 9 when the applied voltage is 2 V is 40%. The transmittance of the transmissive display unit 10 was 2%.

  As described above, all of the liquid crystal display devices obtained in Examples 2 to 4 have a change in transmittance and reflectance in accordance with a change in voltage applied to the liquid crystal display device. Both reflective display and transmissive display were possible.

  Furthermore, when visual observation was performed, in Example 2 and Example 3, by applying the same voltage to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10, Since the voltage applied to the liquid crystal layer 1 by the electrode 7 is maintained in the same manner in the reflective display unit 9 and the transmissive display unit 10, the light and dark changes between the reflective display unit 9 and the transmissive display unit 10. It was the same, and it was confirmed that the display was not reversed. Further, at the time of this display, even if the intensity of ambient light was changed during the observation, the display content was not changed. That is, the transmissive display unit 10 is also dark when the reflective display unit 9 is dark, and the transmissive display unit 10 is also bright when the reflective display 9 is bright. Therefore, display inversion did not occur even when the reflective display unit 9 and the transmissive display unit 10 were driven using the same electrode 7 as shown in FIG.

  On the other hand, in Example 4, when a voltage is applied in the same manner as in Example 2 and Example 3, that is, when a voltage of 1 V is applied, the transmissive display unit 10 is brightly displayed, and the reflective display unit 9 is It became dark display. When a voltage of 2 V was applied, the transmissive display unit 10 was darkly displayed and the reflective display unit 9 was brightly displayed. For this reason, in the transmissive display unit 10 and the reflective display unit 9, the brightness of the display is reversed. Because of this reversal, if the display is performed in an environment with low ambient light, and the reflective display is performed with the ambient light intensified when the transmissive display unit 10 is mainly observed, the brightness of the display is reversed, and the display contents It was difficult to confirm. From this, as shown in Example 4, when the same voltage is applied to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10, reflection in the mixed mode of NB and NW It was confirmed that the reversal of display between the display unit 9 and the transmissive display unit 10 was large and the visibility was deteriorated.

  On the other hand, in Example 4, when the reflective display unit 9 is brightly displayed, the transmissive display unit 10 is also brightly displayed. When the reflective display unit 9 is darkly displayed, the transmissive display unit 10 is also darkly displayed. Different voltages are applied to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10, that is, the reflective display unit 9 displays a dark display on the reflective display unit 9 by the electrodes 6 and 7 (orientation mechanism). When the voltage (1V) shown is applied, a voltage (2V) at which the transmissive display unit 10 becomes dark display is applied to the transmissive display unit 10, and the reflective display unit 9 displays the bright display. When the voltage (2V) is applied, the transmissive display unit 10 is applied with the voltage (1V) at which the transmissive display unit 10 is brightly displayed, thereby eliminating the reversal of display brightness and darkness. A good display state similar to that in Example 3 was obtained.

  From the above, each of the liquid crystal display devices of Examples 2 to 4 has both the brightness of the bright display and the contrast ratio for both the reflective display unit 9 and the transmissive display unit 10. It can be seen that the reflective display unit 9 and the transmissive display unit 10 can match the brightness of the display and can realize a display with excellent visibility. Further, in each of the liquid crystal display devices of Examples 2 to 4, since the contrast ratio in the transmissive display unit 10 exceeds the contrast ratio in the reflective display unit 9, the display quality is further improved and the display is good. It can be seen that can be done.

  Next, among the liquid crystal display devices according to the present embodiment, a liquid crystal display device that uses the polarization conversion action of the liquid crystal layer 1 due to the twist alignment of the liquid crystal layer 1 for display will be described in detail with reference to FIGS. Specific examples and comparative examples will be described, but the liquid crystal display device according to the present embodiment is not limited to the following examples.

Example 5
In this example, the transmissive display unit 10 has a liquid crystal layer thickness of 7.5 μm and the reflective display unit 9 has a liquid crystal layer thickness of 7.5 μm by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1. A liquid crystal cell for liquid crystal injection was produced. That is, also in this embodiment, the photosensitive resin does not remain in the transmissive display portion 10, and in the reflective display portion 9, the insulating film 11 is patterned so that the photosensitive resin is formed with a layer thickness of 3 μm. The transmissive display unit 10 was set to be thicker than the reflective display unit 9.

  However, in this embodiment, as in Embodiments 2 to 4, as shown in FIG. 4, the electrode 7 of the reflective display section 9 and the electrode 7 of the transmissive display section 10 are electrically insulated, and the reflective display section Electrode patterns were prepared so that voltages were separately applied to the electrode 7 and the electrode 7 of the transmissive display unit 10 from the outside.

  In addition, retardation compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. In this embodiment, the phase difference compensation plate 17 is composed of one phase difference compensation plate, and the phase difference compensation plate 16 is composed of two phase difference compensation plates. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  In this example, a liquid crystal display device was manufactured so that the twist orientation (twist angle of the orientation of the liquid crystal (twist angle) of the liquid crystal layer 1 was 70 degrees. Specifically, a voltage was applied to the orientation films 2 and 3. The alignment treatment was performed by using a parallel alignment film and performing a rubbing treatment so that the rubbing crossing angle was 250 degrees so that the liquid crystal alignment when not applied was parallel alignment. The rubbing crossing angle conforms to the above definition, and a liquid crystal composition having a positive dielectric anisotropy having a refractive index difference (Δn) of 0.065 between the electrode substrates in the liquid crystal cell for liquid crystal injection. The liquid crystal layer 1 was formed by introducing the material by a vacuum injection method, and as described above, the twist angle (twist angle of the alignment of the liquid crystal) due to the alignment treatment and the action of the chiral additive added to the liquid crystal composition. 70) Can be. Such liquid crystal layer 1 that is oriented to, in accordance with the applied voltage, the orientation change occurs in response to the voltage from the liquid crystal layer thickness direction central portion of the liquid crystal layer 1.

  Table 2 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

Example 6
Also in this example, in the same manner as in Example 5, a liquid crystal layer in which the transmissive display unit 10 is 7.5 μm and the reflective display unit 9 is 4.5 μm by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1. A liquid crystal cell for liquid crystal injection having a thickness (d) was produced. 4, the electrode 7 of the reflective display unit 9 and the electrode 7 of the transmissive display unit 10 are electrically insulated, and the electrode 7 of the reflective display unit 9 and the electrode 7 of the transmissive display unit 10 In addition, electrode patterns were prepared so that voltages were applied separately from the outside.

  Phase compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. In this embodiment, one retardation compensation plate is used for each of the retardation compensation plate 16 and the retardation compensation plate 17. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  In this example, the liquid crystal display device was manufactured so that the twist alignment of the liquid crystal layer 1 (twist angle of the liquid crystal alignment (twist angle)) was 90 degrees. Specifically, a parallel alignment film is used for the alignment films 2 and 3 so that the liquid crystal alignment when no voltage is applied is parallel alignment, and the rubbing treatment is performed so that the rubbing crossing angle is 270 degrees. Then, the orientation treatment was performed. Note that the rubbing crossing angle follows the above definition. Then, a liquid crystal layer having a positive dielectric anisotropy having a refractive index difference (Δn) of 0.065 is introduced between the electrode substrates in the liquid crystal cell for liquid crystal injection by a vacuum injection method. 1 was formed. By such an alignment treatment and the action of the chiral additive added to the liquid crystal composition, the twist angle (twist angle) of the alignment of the liquid crystal can be set to 90 degrees as described above. In the liquid crystal layer 1 aligned in this way, the change in alignment occurs in accordance with the voltage from the liquid crystal at the center in the layer thickness direction of the liquid crystal layer 1 with the application of voltage.

  Table 2 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

  The optical arrangement shown in Table 2 is the arrangement of each optical element on the display surface when the observer observes the display surface, and the phase difference compensation plate 16 or the phase difference compensation plate 17 has a plurality of phase difference compensations. In the case of being constituted by plates, the phase difference compensation plates constituting the phase difference compensation plates 16 and 17 are described in the order of actual arrangement from the observer side.

  Further, the orientation direction of the liquid crystal layer 1 (the orientation direction of the major axis of the liquid crystal molecule) is equal to the orientation of the rubbing treatment applied to the alignment film 2 on the substrate 4 side on the substrate 4 side, and on the substrate 5 side on the substrate 5 side. This is equal to the orientation of the rubbing treatment applied to the alignment film 3. However, when the orientation orientation of the liquid crystal in contact with the orientation film 2 is traced to the orientation film 3 side, the twist orientation is 90 degrees to the left. When the liquid crystal alignment is tracked as described above, the rubbing treatment direction to the alignment film 2 is considered to be the alignment direction on the substrate 4 side (hereinafter abbreviated as the substrate 4 alignment direction). The azimuth is an azimuth reversed 180 degrees from the azimuth obtained by tracking the orientation of the liquid crystal according to the twist. Hereinafter, the orientation orientation on the substrate 5 side (hereinafter abbreviated as the orientation orientation of the substrate 5) is defined as the liquid crystal orientation on the substrate 5 obtained by tracking the orientation of the liquid crystal from the orientation orientation of the substrate 4 according to the twist.

  Each orientation in Table 2 represents an orientation from a reference orientation arbitrarily taken on the display surface in units of degrees, and the retardation of each retardation compensation plate represents a value for monochromatic light having a wavelength of 550 nm in nm units.

  The display characteristics of the liquid crystal display devices obtained in Examples 5 and 6 are shown in FIGS. 9 and 10, respectively. All of these display characteristics were measured by the same method as in Example 1. In each figure, the horizontal axis represents the effective value of the applied voltage, and the vertical axis represents the brightness (reflectance or transmission). Rate). Further, the transmittance of the transmissive display unit 10 to which neither of the polarizing plates 14 and 15 is attached is 100%, and the reflectance of the reflective display unit 9 before the polarizing plate 14 is attached is 100% of reflectance.

  In FIG. 9, a curve 241 shows the voltage dependence of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 5, and the curve 242 shows the example. 5 shows the voltage dependency of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in 5.

  As shown in FIG. 9, in Example 5, both the reflectance and the transmittance are increased as the applied voltage is increased in the section where the applied voltage is 1.2 V or more. The reflectance of the reflective display unit 9 when the applied voltage is 1 V is 3%, the transmittance of the transmissive display unit 10 is 2%, and the reflectance of the reflective display unit 9 when the applied voltage is 4 V is 41%. The transmittance of the transmissive display unit 10 was 40%.

  In FIG. 10, a curve 251 indicates the voltage dependence of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 6, and the curve 252 is The voltage dependence of the transmittance | permeability of the transmissive display part 10 with respect to the voltage between the electrode 6 in the liquid crystal display device obtained in Example 6 and the electrode 7 is shown.

  As shown in FIG. 10, in Example 6, as in Example 5, both the reflectance and the transmittance are increased as the applied voltage is increased in the section where the applied voltage is 1.2 V or higher. In Example 6, the reflectance of the reflective display unit 9 when the applied voltage is 1V is 3%, the transmittance of the transmissive display unit 10 is 2%, and the reflective display unit 9 when the applied voltage is 4V. The reflectance was 35%, and the transmittance of the transmissive display unit 10 was 37%.

  As described above, the liquid crystal display devices obtained in Examples 5 and 6 both change in transmittance and reflectance according to the change in the voltage applied to the liquid crystal display device. Both reflective display and transmissive display were possible.

  Furthermore, when visual observation was performed, in Example 5 and Example 6, by applying the same voltage to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10, Even when the voltage applied to the liquid crystal layer 1 by the electrode 7 is maintained in the same manner in the reflective display unit 9 and the transmissive display unit 10, changes in brightness between the reflective display unit 9 and the transmissive display unit 10 are performed. Was the same, and it was confirmed that the display was not reversed. Further, at the time of this display, even if the intensity of ambient light was changed during the observation, the display content was not changed. That is, when the reflective display unit 9 is dark, the transmissive display unit 10 is also dark, and when the reflective display unit 9 is bright, the transmissive display unit 10 is also bright. For this reason, in the fifth and sixth embodiments, the display is not inverted even when the reflective display unit 9 and the transmissive display unit 10 are driven using the same electrode 7 as shown in FIG. It was.

  Accordingly, each of the liquid crystal display devices of Examples 5 and 6 can achieve both the brightness and contrast ratio of bright display for both the reflective display unit 9 and the transmissive display unit 10. In addition, the reflective display portion 9 and the transmissive display portion 10 can match the brightness of the display, and a display with excellent visibility can be realized. Further, in each of the liquid crystal display devices of Examples 5 and 6, since the contrast ratio in the transmissive display unit 10 exceeds the contrast ratio in the reflective display unit 9, the display quality is further improved and the display is good. Can be realized.

  Further, in the sixth embodiment, the number of retardation compensation plates used is smaller than that in the fifth embodiment, and the reflected light and transmitted light are excellent in visibility and capable of high-resolution color display (color display). Can be provided at a lower cost.

  In the above embodiment, the liquid crystal display device that performs good reflective display and good transmissive display by changing the liquid crystal layer thickness between the reflective display portion and the transmissive display portion has been described. In the following description, a liquid crystal display device will be described in which the liquid crystal layer thickness in the reflective display portion and the liquid crystal layer thickness in the transmissive display portion are set to be equal, and a good reflective display and a good transmissive display are performed.

[Embodiment 3]
In the present embodiment, when the liquid crystal layer thickness in the reflective display unit and the liquid crystal layer thickness in the transmissive display unit are equal, the voltage applied between the reflective display unit and the transmissive display unit is changed to change the liquid crystal alignment to the reflective display unit. A liquid crystal display device that realizes a good reflective display and a good transmissive display by making it different from the transmissive display portion will be described.

  In the present embodiment, for such a liquid crystal display device, in the liquid crystal display device using the polarizing plates 14 and 15 described in the second embodiment and utilizing the retardation of the liquid crystal layer 1 for display, a reflective display unit 9 and the transmissive display unit 10 will be described with reference to FIG. 4 and FIGS. 11 to 16 using specific examples and comparative examples, taking as an example a case where the liquid crystal layer thickness is set to be equal. To do. However, the liquid crystal display device according to the present embodiment is not limited to the following examples.

  For convenience of explanation, components having the same functions as those in the first and second embodiments are denoted by the same reference numerals, and description thereof is omitted. The specific overall configuration of the liquid crystal display device according to the present embodiment is the same as that of the second embodiment except that the reflective display unit 9 and the transmissive display unit 10 are set to have the same liquid crystal layer thickness. Therefore, the description thereof is omitted here.

  In order to set the liquid crystal layer thickness to be equal between the reflective display portion 9 and the transmissive display portion 10 as shown in the present embodiment, for example, without forming the insulating film 11 formed on the substrate 5. The electrode 7 may be formed directly on the substrate 5.

Example 7
In the present embodiment, the insulating film 11 made of an insulating photosensitive resin is not formed on the substrate 5 in the first embodiment, and as shown in FIG. An electrode pattern is prepared so that the electrode 7 of the part 10 is electrically insulated and a voltage is separately applied to the electrode 7 of the reflective display part 9 and the electrode 7 of the transmissive display part 10 from the outside of the liquid crystal cell. Except for the above, both the reflective display unit 9 and the transmissive display unit 10 have a liquid crystal layer thickness (d) of 4.5 μm by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1. A liquid crystal cell for liquid crystal injection was produced.

  Then, the liquid crystal composition for liquid crystal injection has a refractive index difference (Δn) of a liquid crystal composition containing no chiral agent of 0.065 and a positive dielectric anisotropy. Thus, the liquid crystal layer 1 was formed.

  Phase compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. In this embodiment, the phase difference compensation plate 17 is composed of two phase difference compensation plates, and the phase difference compensation plate 16 is composed of two phase difference compensation plates. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  In this embodiment, the liquid crystal layer 1 is a liquid crystal layer in which liquid crystal is aligned parallel to the substrates 4 and 5 (parallel to the display surface) and not twisted. The birefringence mode using the retardation of the liquid crystal layer 1 for display was used.

  In this embodiment, the retardation suitable for reflective display is used for the transmissive display unit 10. Here, the reflective display unit 9 is set in the same manner as the reflective display unit 9 of Example 2 in the second embodiment, but the transmissive display unit 10 has a liquid crystal layer thickness set equal to that of the reflective display unit 9. This is different from the second embodiment. For this reason, in this embodiment, the optical design is performed again in the second embodiment, and the optical arrangement of the polarizing plates 14 and 15 and the optical arrangement of the phase difference compensation plates 16 and 17 are determined. In this embodiment, the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 is set so that the dark display of the transmissive display unit 10 is good.

  Further, in this embodiment, as in the second embodiment, a parallel alignment film is used as the alignment films 2 and 3 so that the liquid crystal is aligned in parallel with the display surface when no voltage is applied. The alignment treatment was performed with the rubbing crossing angle of the films 2 and 3 set to 180 degrees.

  In such an alignment treatment, the twist angle (twist angle) of the alignment of the liquid crystal is 0 degree, and the change in alignment occurs in accordance with the voltage from the liquid crystal at the center in the layer thickness direction of the liquid crystal layer 1 with the application of voltage. .

  Table 3 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

[Comparative Example 3]
Here, the comparative example of said Example 7 is shown. In Comparative Example 3, in the liquid crystal display device shown in Example 7, the phase difference compensation plate 16 is composed of two phase difference compensation plates, while the phase difference compensation plate 17 is composed of one phase difference compensation plate. The liquid crystal display device was designed in the same manner as the liquid crystal display device shown in Example 7 except that the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 was set so that the bright display of the transmissive display unit 10 would be good. A liquid crystal display device was produced. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  Also in this comparative example, as in the case of Example 7, a parallel alignment film is used as the alignment films 2 and 3 so that the liquid crystal is aligned in parallel with the display surface when no voltage is applied. The alignment treatment was performed with the rubbing crossing angle of the films 2 and 3 set to 180 degrees.

  In such an alignment treatment, the twist angle (twist angle) of the alignment of the liquid crystal is 0 degree, and the change in alignment occurs in accordance with the voltage from the liquid crystal at the center in the layer thickness direction of the liquid crystal layer 1 with the application of voltage. .

  Table 3 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this comparative example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

Example 8
In this example, in the liquid crystal display device shown in Example 7, the liquid crystal layer thickness (d) in the reflective display unit 9 and the liquid crystal layer thickness (d) in the transmissive display unit 10 are both 7.5 μm, and thus transmissive display is achieved. A liquid crystal display device shown in Example 7 is used except that a suitable retardation is used for the reflective display unit 9 and the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 is set so that the reflective display is good. A liquid crystal display device designed in the same manner as described above was produced.

  More specifically, in this embodiment, the insulating film 11 made of a photosensitive resin having insulating properties is not formed on the substrate 5 in the first embodiment, and the reflective display portion 9 is formed as shown in FIG. The electrode 7 and the electrode 7 of the transmissive display unit 10 are electrically insulated, and voltages are separately applied to the electrode 7 of the reflective display unit 9 and the electrode 7 of the transmissive display unit 10 from the outside of the liquid crystal cell. The reflective display portion 9 and the transmissive display portion 10 are both 7.5 μm thick with a liquid crystal layer thickness (d) by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1, except that the electrode pattern was prepared as described above. A liquid crystal cell for injecting liquid crystal was prepared.

  Then, the liquid crystal composition for liquid crystal injection has a refractive index difference (Δn) of a liquid crystal composition containing no chiral agent of 0.065 and a positive dielectric anisotropy. Thus, the liquid crystal layer 1 was formed.

  Phase compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. In this embodiment, the phase difference compensation plate 17 is composed of two phase difference compensation plates, and the phase difference compensation plate 16 is composed of two phase difference compensation plates. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  In this embodiment, the liquid crystal layer 1 is a liquid crystal layer in which liquid crystal is aligned parallel to the substrates 4 and 5 (parallel to the display surface) and not twisted. The birefringence mode using the retardation of the liquid crystal layer 1 for display was used.

  In this embodiment, retardation suitable for transmissive display is used for the reflective display unit 9. Here, the transmissive display unit 10 is set in the same manner as the transmissive display unit 10 of Example 2 in the second embodiment, but the reflective display unit 9 has a liquid crystal layer thickness set equal to that of the transmissive display unit 10. This is different from the second embodiment. For this reason, in this embodiment, the optical design is performed again in the second embodiment, and the optical arrangement of the polarizing plates 14 and 15 and the optical arrangement of the phase difference compensation plates 16 and 17 are determined. In this embodiment, the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 is set so that the reflective display is good.

  Further, in this embodiment, as in the second embodiment, a parallel alignment film is used as the alignment films 2 and 3 so that the liquid crystal is aligned in parallel with the display surface when no voltage is applied. The alignment treatment was performed with the rubbing crossing angle of the films 2 and 3 set to 180 degrees.

  In such an alignment treatment, the twist angle (twist angle) of the alignment of the liquid crystal is 0 degree, and the change in alignment occurs in accordance with the voltage from the liquid crystal at the center in the layer thickness direction of the liquid crystal layer 1 with the application of voltage. .

  Table 3 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

  The optical arrangement shown in Table 3 is the arrangement of each optical element on the display surface when the observer observes the display surface. The phase difference compensation plate 16 or the phase difference compensation plate 17 has a plurality of phase difference compensations. In the case of being constituted by plates, the phase difference compensation plates constituting the phase difference compensation plates 16 and 17 are described in the order of actual arrangement from the observer side.

  Further, since the liquid crystal layer 1 has a non-twisted orientation, the orientation direction of the entire liquid crystal layer 1 when no voltage is applied (the orientation orientation of the liquid crystal molecule major axis) is described. This is the direction of the rubbing treatment applied to the alignment film 2 on the side.

  In addition, each azimuth | direction represents the azimuth | direction from the reference | standard azimuth | direction arbitrarily taken on the display surface in the unit of a degree, and the retardation of each phase difference compensation board shows the value with respect to the monochromatic light of wavelength 550nm in a nm unit.

[Comparative Example 4]
In this comparative example, in the liquid crystal display device shown in Example 7, the liquid crystal is aligned in the liquid crystal layer 1 in parallel to the substrates 4 and 5 (parallel to the display surface) and twisted by 70 degrees. A liquid crystal display device designed in the same manner as the liquid crystal display device shown in Example 7 was produced except that the liquid crystal layer was used and the polarization conversion action of the liquid crystal layer 1 due to the twist alignment of the liquid crystal layer 1 was used for display.

  More specifically, in this comparative example, the insulating film 11 made of a photosensitive resin having insulating properties is not formed on the substrate 5 in Example 1, and the reflective display portion 9 is not formed as shown in FIG. The electrode 7 and the electrode 7 of the transmissive display unit 10 are electrically insulated, and voltages are separately applied to the electrode 7 of the reflective display unit 9 and the electrode 7 of the transmissive display unit 10 from the outside of the liquid crystal cell. The reflective display portion 9 and the transmissive display portion 10 are both 4.5 μm in thickness of the liquid crystal layer (d) by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1 except that the electrode pattern was prepared as described above. A liquid crystal cell for injecting liquid crystal was prepared.

  In addition, retardation compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. In this comparative example, the phase difference compensation plate 17 is composed of two phase difference compensation plates, and the phase difference compensation plate 16 is composed of two phase difference compensation plates. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  Further, in this comparative example, a parallel alignment film is used for the alignment films 2 and 3 so that the liquid crystal alignment when no voltage is applied is parallel alignment, and the rubbing crossing angle is 250 degrees. By performing a rubbing process, an alignment process was performed. Note that the rubbing crossing angle follows the above definition. Then, a liquid crystal layer having a positive dielectric anisotropy having a refractive index difference (Δn) of 0.065 is introduced between the electrode substrates in the liquid crystal cell for liquid crystal injection by a vacuum injection method. 1 was formed. By such an alignment treatment and the action of the chiral additive added to the liquid crystal composition, the twist angle (twist angle) of the alignment of the liquid crystal can be set to 70 degrees as described above. The amount of the chiral additive added is adjusted so that the twist angle described above can be obtained. In the liquid crystal layer 1 aligned in this way, the change in alignment occurs in accordance with the voltage from the liquid crystal at the center in the layer thickness direction of the liquid crystal layer 1 with the application of voltage.

  In this comparative example, the product (Δn · d) of the refractive index difference (Δn) of the liquid crystal composition suitable for reflective display and the liquid crystal layer thickness (d) was used for the transmissive display unit 10. Here, the reflective display unit 9 is set in the same manner as the reflective display unit 9 of Example 5 in the second embodiment, but the transmissive display unit 10 has a liquid crystal layer thickness set equal to that of the reflective display unit 9. This is different from the fifth embodiment. For this reason, in this comparative example, in Example 5, the optical design is performed again, and the optical arrangement of the polarizing plates 14 and 15 and the optical arrangement of the phase difference compensation plates 16 and 17 are determined. In this comparative example, the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 is set so that the dark display of the transmissive display unit 10 is good.

  Table 4 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this comparative example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

[Comparative Example 5]
In this comparative example, in the liquid crystal display device shown in comparative example 4, except that the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 was set so that the bright display of the transmissive display unit 10 would be good. A liquid crystal display device designed in the same manner as the liquid crystal display device shown in Comparative Example 4 was produced. That is, in this comparative example, in the liquid crystal display device shown in Example 7, the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 is set so that the bright display of the transmissive display unit 10 is good. In addition, a liquid crystal layer in which the liquid crystal is aligned parallel to the substrates 4 and 5 (parallel to the display surface) and twisted by 70 degrees is used for the liquid crystal layer 1. A liquid crystal display device designed in the same manner as the liquid crystal display device shown in Example 7 was produced except that the polarization conversion action of the liquid crystal layer 1 due to the above was used for display.

  Table 4 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this comparative example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

Example 9
In this example, in the liquid crystal display device shown in Example 8, the phase difference compensation plate 16 is composed of two phase difference compensation plates, while the phase difference compensation plate 17 is composed of one phase difference compensation plate, For the liquid crystal layer 1, a liquid crystal layer in which liquid crystal is aligned parallel to the substrates 4 and 5 (parallel to the display surface) and twisted by 70 degrees is used. A liquid crystal display device designed in the same manner as the liquid crystal display device shown in Example 8 was produced except that the polarization conversion action of the layer 1 was used for display.

  More specifically, in this embodiment, the insulating film 11 made of a photosensitive resin having insulating properties is not formed on the substrate 5 in the first embodiment, and the reflective display portion 9 is formed as shown in FIG. The electrode 7 and the electrode 7 of the transmissive display unit 10 are electrically insulated, and voltages are separately applied to the electrode 7 of the reflective display unit 9 and the electrode 7 of the transmissive display unit 10 from the outside of the liquid crystal cell. The reflective display portion 9 and the transmissive display portion 10 are both 7.5 μm thick with a liquid crystal layer thickness (d) by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1, except that the electrode pattern was prepared as described above. A liquid crystal cell for injecting liquid crystal was prepared.

  In addition, retardation compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. In this embodiment, the phase difference compensation plate 17 is composed of one phase difference compensation plate, and the phase difference compensation plate 16 is composed of two phase difference compensation plates. The sticking directions of the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 were determined corresponding to the alignment direction (alignment direction) of the liquid crystal.

  In this example, the liquid crystal display device was manufactured so that the twist alignment of the liquid crystal layer 1 (the twist angle of the liquid crystal alignment (twist angle)) was 70 degrees. Specifically, a parallel alignment film is used for the alignment films 2 and 3 so that the liquid crystal alignment is parallel when no voltage is applied, and the rubbing treatment is performed so that the rubbing crossing angle is 250 degrees. Then, the orientation treatment was performed. Note that the rubbing crossing angle follows the above definition. Then, a liquid crystal composition having a positive dielectric anisotropy having a refractive index difference (Δn) of 0.065 is introduced between the electrode substrates in the liquid crystal cell for liquid crystal injection by a vacuum injection method. Thus, the liquid crystal layer 1 was formed. By such an alignment treatment and the action of the chiral additive added to the liquid crystal composition, the twist angle (twist angle) of the alignment of the liquid crystal can be set to 70 degrees as described above. The amount of the chiral additive added is adjusted so that the twist angle described above can be obtained. In the liquid crystal layer 1 aligned in this way, the change in alignment occurs in accordance with the voltage from the liquid crystal at the center in the layer thickness direction of the liquid crystal layer 1 with the application of voltage.

  In this example, the product (Δn · d) of the refractive index difference (Δn) and the liquid crystal layer thickness (d) of the liquid crystal composition suitable for transmissive display was used for the reflective display unit 9. Here, the transmissive display unit 10 is set in the same manner as the transmissive display unit 10 of Example 5 in the second embodiment, but the reflective display unit 9 is set to have a liquid crystal layer thickness equal to that of the transmissive display unit 10. This is different from the fifth embodiment. For this reason, in this embodiment, the optical design is performed again in the fifth embodiment, and the optical arrangement of the polarizing plates 14 and 15 and the optical arrangement of the phase difference compensation plates 16 and 17 are determined. In this embodiment, the optical arrangement of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17 is set so that the reflective display is good.

  Table 4 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking orientations and liquid crystal orientation orientations) are shown using a common orientation reference.

  The optical arrangement shown in Table 4 is an arrangement of each optical element on the display surface when the observer observes the display surface, and the phase difference compensation plate 16 or the phase difference compensation plate 17 has a plurality of phase difference compensations. In the case of being constituted by plates, the phase difference compensation plates constituting the phase difference compensation plates 16 and 17 are described in the order of actual arrangement from the observer side. Each orientation in Table 4 represents an orientation from a reference orientation arbitrarily taken on the display surface in units of degrees, and the retardation of each retardation compensation plate indicates a value for monochromatic light having a wavelength of 550 nm in nm units.

  As described above, in the liquid crystal display devices according to Example 7 and Comparative Examples 3 to 5 having a liquid crystal layer thickness (d) of 4.5 μm, the liquid crystal layer thickness is set to be suitable for reflective display. For this reason, in the said Example 7 and Comparative Examples 3-5, the optical arrangement | positioning of the polarizing plate 14 and the phase difference compensating plate 16 which are related only to reflective display is set so that it may be suitable for reflective display. On the other hand, the liquid crystal layer thickness of the transmissive display unit 10 is set to be different from the liquid crystal layer thickness of the transmissive display unit 10 of the liquid crystal display device in each example of the second embodiment. For this reason, in the said Example 7 and Comparative Examples 3-5, the optical arrangement | positioning of the phase difference compensation plate 17 and the polarizing plate 15 was set according to the optical characteristic of the transmissive display part 10 of each liquid crystal display device. That is, in Example 7 and Comparative Example 4, a liquid crystal display device capable of realizing good dark display was produced, and in Comparative Example 3 and Comparative Example 5, a liquid crystal display device capable of realizing good bright display was produced. .

  On the other hand, in the liquid crystal display devices according to Examples 8 and 9 having a liquid crystal layer thickness (d) of 7.5 μm, the liquid crystal layer thickness is set to be suitable for transmissive display. For this reason, in Example 8 and Example 9 described above, the optical arrangement of the polarizing plate 14, the phase difference compensation plate 16, the phase difference compensation plate 17, and the polarizing plate 15 related to transmissive display is suitable for transmissive display. It is set. Therefore, in the above-described eighth and ninth embodiments, the display characteristics of the reflective display unit 9 are determined by the optical arrangement of the polarizing plate 14 and the phase difference compensation plate 16 set in accordance with the transmissive display.

  Further, the display characteristics of the liquid crystal display devices obtained in Example 7, Comparative Example 3, Example 8, Comparative Example 4, Comparative Example 5, and Example 9 are shown in FIGS. 11, 12, 13, respectively. It shows in FIG. 14, FIG. These display characteristics were measured using a microscope in the same manner as in Example 1. In each of the above figures, the horizontal axis represents the effective value of the applied voltage, and the vertical axis represents the brightness (reflectance). Or transmittance). Further, the transmittance of the transmissive display unit 10 to which neither of the polarizing plates 14 and 15 is attached is 100%, and the reflectance of the reflective display unit 9 before the polarizing plate 14 is attached is 100% of reflectance.

  In FIG. 11, a curve 261 shows the voltage dependence of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 in the liquid crystal display device obtained in Example 7, and the curve 262 shows the example. 7 shows the voltage dependency of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in step 7.

  As shown in FIG. 11, in Example 7, in the section where the applied voltage is 1 V to 3 V, the transmittance increases as the applied voltage increases, while the reflectance is applied in the section where the applied voltage is 1 V to 2 V. The voltage increases as the voltage increases, and thereafter decreases as the applied voltage increases. The reflectance of the reflective display unit 9 is 3% when the applied voltage is 1V, the transmittance of the transmissive display unit 10 is 3%, and the reflectance of the reflective display unit 9 is 40% when the applied voltage is 2V. The transmittance of the transmissive display unit 10 was 18%, the reflectance of the reflective display unit 9 when the applied voltage was 3 V was 28%, and the transmittance of the transmissive display unit 10 was 33%.

  In FIG. 12, a curve 271 indicates the voltage dependency of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Comparative Example 3, and the curve 272 indicates The voltage dependence of the transmittance | permeability of the transmissive display part 10 with respect to the voltage between the electrode 6 in the liquid crystal display device obtained by the comparative example 3 and the electrode 7 is shown.

  As shown in FIG. 12, in Comparative Example 3, both the reflectance and the transmittance are increased as the applied voltage is increased in the section where the applied voltage is 1V to 2V. The reflectance of the reflective display unit 9 when the applied voltage is 1 V is 3%, the transmittance of the transmissive display unit 10 is 18%, and the reflectance of the reflective display unit 9 when the applied voltage is 2 V is 40%. The transmittance of the transmissive display unit 10 was 40%.

  In FIG. 13, a curve 281 indicates the voltage dependency of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 8, and the curve 282 indicates the Example. 8 shows the voltage dependency of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in Step 8;

  As shown in FIG. 13, in Example 8, in the section where the applied voltage is 1V to 2V, the transmittance increases with the increase of the applied voltage, while the reflectance is 0.7V to 1.2V. After the voltage increases with the increase of the applied voltage in the interval, the applied voltage decreases once with the increase of the applied voltage in the interval of 1.2V to 1.7V, and then the applied voltage becomes 1.7V to 2.V. In the section of 3V, it rises again as the applied voltage rises. The reflectance of the reflective display unit 9 when the applied voltage is 1V is 24%, the transmittance of the transmissive display unit 10 is 3%, and the reflectance of the reflective display unit 9 when the applied voltage is 1.2V is The reflectance of the reflective display unit 9 is 40% when the applied voltage is 1.7V, the reflectance of the reflective display unit 9 is 27% when the applied voltage is 2V, and the transmittance of the transmissive display unit 10. Was 39%.

  In FIG. 14, a curve 291 indicates the voltage dependency of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Comparative Example 4, and the curve 292 indicates the comparative example. 4 shows the voltage dependence of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in item 4.

  As shown in FIG. 14, in Comparative Example 4, in the section where the applied voltage is 1.2 V to 3 V, both the reflectance and the transmittance are increased as the applied voltage is increased. The reflectance of the reflective display unit 9 when the applied voltage is 1.2 V is 3%, the transmittance of the transmissive display unit 10 is 1%, and the reflectance of the reflective display unit 9 when the applied voltage is 3 V is The transmittance of the transmissive display unit 10 was 36% and 16%.

  In FIG. 15, a curve 311 shows the voltage dependence of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Comparative Example 5, and a curve 312 shows the comparative example. 5 shows the voltage dependency of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in 5.

  As shown in FIG. 15, in the comparative example 5, in the area where the applied voltage is 1.2V to 3V, both the reflectance and the transmittance are increased as the applied voltage is increased. The reflectance of the reflective display unit 9 when the applied voltage is 1.2V is 3%, the transmittance of the transmissive display unit 10 is 21%, and the reflectance of the reflective display unit 9 when the applied voltage is 3V is The transmittance of 39% and the transmissive display unit 10 was 35%.

  In FIG. 16, a curve 321 indicates the voltage dependency of the reflectance of the reflective display unit 9 with respect to the voltage between the electrodes 6 and 7 in the liquid crystal display device obtained in Example 9, and the curve 322 indicates the example. 9 shows the voltage dependence of the transmittance of the transmissive display unit 10 with respect to the voltage between the electrode 6 and the electrode 7 in the liquid crystal display device obtained in 9.

  As shown in FIG. 16, in Example 9, in the section where the applied voltage is 1.2V to 3V, the transmittance increases with the increase of the applied voltage, while the reflectance is 0.9V to 1 It decreases once with the increase of the applied voltage in the section of .7V, and thereafter increases with the increase of the applied voltage. Further, the reflectance of the reflective display unit 9 when the applied voltage is 1.2V is 7%, the transmittance of the transmissive display unit 10 is 32%, and the reflection of the reflective display unit 9 when the applied voltage is 1.7V. The reflectance was 3%, the reflectance of the reflective display portion 9 when the applied voltage was 3 V was 37%, and the transmittance of the transmissive display portion 10 was 36%.

  As is apparent from the above examples and comparative examples, in the liquid crystal display device using the polarizing plates 14 and 15 and utilizing the change in the polarization state due to the polarization conversion action such as retardation and rotation of the liquid crystal layer 1 for display, When the thickness of the liquid crystal layer of the layer 1 is matched between the reflective display unit 9 and the transmissive display unit 10, the same voltage is applied to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10 (reflective display unit 9). When the display unit 9 and the transmissive display unit 10 are driven with a common voltage), as shown in Example 7 and Comparative Examples 3-5, the brightness and contrast ratio of the bright display are sufficient for the reflective display unit 9. When applying a voltage compatible with both, the brightness of the bright display of the transmissive display unit 10 and the contrast ratio are not sufficient, and the brightness and contrast ratio of the bright display are transmissively displayed as shown in the eighth and ninth embodiments. 10 in part 10 It does not match the change in the brightness of the transmissive display section 10 and the change in the brightness of the reflective display portion 9 at the time of application of voltage compatible to, not a good display.

  However, the liquid crystal display devices obtained in Example 7, Example 8, and Example 9 all apply different voltages to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10. A good display can be obtained by driving the reflective display unit 9 and the transmissive display unit 10 with different voltages.

  That is, in each of the liquid crystal display devices of Examples 7 to 9, the reflective display unit is configured such that different voltages are applied to the electrode 7 in the reflective display unit 9 and the electrode 7 in the transmissive display unit 10. 9 and the transmissive display unit 10 can achieve both a bright display brightness and a contrast ratio, and the reflective display unit 9 and the transmissive display unit 10 can match the display brightness. It can be seen that a display with excellent visibility can be realized.

  As a result of comparison between the present embodiment and the second embodiment, in the liquid crystal display device using the polarizing plates 14 and 15 and utilizing the polarization conversion action such as retardation and rotation of the liquid crystal layer 1 for display, the reflective display unit 9 and the transmissive display unit 10, the thickness of the liquid crystal layer 1 in the transmissive display unit 10 is set to be larger than the layer thickness of the liquid crystal layer 1 in the transmissive display unit 9. It turns out that is effective.

  In each of the embodiments of the present embodiment and the second embodiment, the liquid crystal display mode is such that the liquid crystal alignment in a state where no voltage is applied is parallel to the plane direction of the display surface. Using a vertical alignment mode, a hybrid alignment mode, or the like by using a liquid crystal material having a property different from the liquid crystal material exemplified in each of the above embodiments or using an alignment film having a property different from the exemplified alignment film. Needless to say, you can.

  Further, regardless of whether the liquid crystal display mode is a mode using retardation or optical rotation of the liquid crystal layer 1, the liquid crystal layer thickness affects the optical characteristics, and the liquid crystal layer thickness in the reflective display unit 9 is in the transmissive display unit 10. Needless to say, the present invention realizes good optical characteristics for those that are thinner than the liquid crystal layer.

  Further, in Example 4 and Examples 7 to 9, it is possible to display well by applying different voltages between the reflective display unit 9 and the transmissive display unit 10 by the electrodes 6 and 7 (orientation mechanism). It turns out that it becomes. In this case, for example, in Example 4 and Example 7, it is possible to improve the display of the transmissive display unit 10 by sufficiently applying a voltage to the transmissive display unit 10. Further, in both Example 8 and Example 9, good display becomes possible by adjusting the voltage of the reflective display unit 9. Therefore, according to the present embodiment and the second embodiment, in addition to the method of changing the liquid crystal layer thickness between the reflective display unit 9 and the transmissive display unit 10, the voltage between the reflective display unit 9 and the transmissive display unit 10 is It can be seen that a good display can be realized by preparing a liquid crystal cell in advance so that can be changed.

[Embodiment 4]
In the present embodiment, the alignment processing direction (rubbing direction) on the substrate for determining the liquid crystal alignment, that is, the alignment processing direction of the alignment film provided on each electrode substrate is changed between the reflective display unit and the transmissive display unit. A liquid crystal display device that realizes good reflective display and good transmissive display by changing the liquid crystal orientation between the reflective display portion and the transmissive display portion will be described.

  In this embodiment mode, a so-called rubbing method is used to uniformly align the liquid crystal layer. In this embodiment, the alignment film surface is covered with a photoresist or the like during the rubbing process of the alignment film in order to change the alignment processing direction of the alignment film provided on each electrode substrate between the reflective display portion and the transmissive display portion. Therefore, at least two types of liquid crystal alignment can be realized. According to this method, it is possible to simultaneously realize liquid crystal alignment suitable for reflective display and liquid crystal alignment suitable for transmissive display. As a result, it is possible to realize good reflective display and good transmissive display. Become.

  Hereinafter, the liquid crystal display device according to the present embodiment will be described in more detail. For convenience of explanation, the same reference numerals are given to components having the same functions as those of the first to third embodiments, and The description is omitted.

  First, with reference to FIG. 17 and FIGS. 18A to 18E, an alignment process step of the substrate (electrode substrate 40) used in the liquid crystal display device according to the present embodiment will be described.

  First, as shown in FIG. 18A, an alignment film material is formed on the contact surface with the liquid crystal layer 1 in a substrate 41 (corresponding to the substrate 4 after the electrode 6 is formed or the substrate 5 after the electrode 7 is formed) constituting the liquid crystal cell. (S1), pre-bake (S2), and curing (S3) to form an alignment film 42 (corresponding to the alignment film 2 or alignment film 3) on the contact surface of the substrate 41 with the liquid crystal layer 1. .

  Next, the alignment film 42 is subjected to a rubbing process to perform an alignment process on the electrode substrate 40 provided with the alignment film 42 at the interface with the liquid crystal layer 1 on the substrate 41. At this time, in the present embodiment, first, as shown in FIG. 18B, a screen with a resist 43 for rubbing processing screen is performed so that the rubbing processing is partially performed. In this case, first, a resist material for rubbing processing screen is applied on the alignment film 42 (S4), and after pre-baking (S5), a part of the alignment film 42 (first alignment processing region 42a) is exposed. As described above, UV mask exposure (S6), development (S7), and curing (S8) are performed, and then the first alignment processing region 42a is rubbed (S9). Next, after the rubbing treatment of the electrode substrate 40 (S10), as shown in FIG. 18C, the resist 43 is peeled off (S11).

  Subsequently, in order to realize a liquid crystal alignment different from the liquid crystal alignment in the first alignment treatment region 42a, as shown in FIG. 18D, the already rubbed portion (the first alignment treatment region 42a) is formed. The rubbing screen resist is protected by a resist 44, and the untreated portion is rubbed. That is, a resist material for a rubbing process screen is applied on the alignment film 42 from which the resist 43 has been peeled off (S12), and after pre-baking (S13), an alignment process other than the first alignment process region 42a on the alignment film 42 is performed. UV mask exposure (S14), development (S15), and curing (S16) are performed so that the region (second alignment treatment region 42b) is exposed, and then the second alignment treatment region 42b A rubbing process is performed so that the processing orientation is different from that of the first alignment processing area 42a (S17). Next, after the rubbing treatment of the electrode substrate 40 (S18), the resist 44 is removed as shown in FIG. 18E (S19). As a result, an alignment film 42 (orientation mechanism) that has been aligned in two different orientations was obtained.

  Thus, in this embodiment, the alignment process patterned with the resist is performed twice or more. At this time, at least two types of liquid crystal alignments (for example, alignment directions) are obtained by changing the processing direction for each alignment process (in the above description, two alignment processes are performed by two alignment processes). Can be realized). In this way, by changing the orientation processing direction on at least one substrate (electrode substrate), the orientation of the reflective display unit 9 and the transmissive display unit 10 can be set independently, and a good display can be obtained. It becomes possible.

  Next, a liquid crystal display device that realizes different liquid crystal alignments in the reflective display unit 9 and the transmissive display unit 10 by the above-described method and uses the polarizing plates 14 and 15 will be described below using specific examples. . However, the liquid crystal display device according to the present embodiment is not limited to the following examples.

Example 10
In this example, a liquid crystal display device was manufactured according to the method for manufacturing a liquid crystal display device shown in Comparative Example 5. Specifically, in Example 1, the insulating film 11 made of an insulating photosensitive resin is not formed on the substrate 5, and as shown in FIG. The electrode 7 of the part 10 is electrically insulated, and an electrode pattern is prepared so that a voltage is separately applied to the electrode 7 of the reflective display part 9 and the electrode 7 of the transmissive display part 10 from the outside. The reflective display unit 9 and the transmissive display unit 10 both have a liquid crystal layer thickness (d) (cell gap) of 4.5 μm by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1. A liquid crystal cell for injecting liquid crystal was prepared. Then, retardation compensation plates 16 and 17 and polarizing plates 14 and 15 were attached to the outside of each electrode substrate in the liquid crystal cell. The phase difference compensation plate 16 and the phase difference compensation plate 17 are each composed of two phase difference compensation plates.

  However, in this example, alignment division was performed during the rubbing treatment of the alignment film 3 by the same method as the method shown in FIGS. 17 and 18A to 18E. That is, in this embodiment, the alignment film 2 on the substrate 4 side is rubbed in the same direction in the reflective display unit 9 and the transmissive display unit 10, and the alignment film 3 (orientation mechanism) on the substrate 5 side is rubbed. Thus, the reflective display unit 9 and the transmissive display unit 10 were rubbed in different directions so that the liquid crystal alignment directions were different between the reflective display unit 9 and the transmissive display unit 10.

  In the present embodiment, the reflective display unit 9 uses a liquid crystal display mode that is parallel to the display surface (parallel to the substrates 4 and 5) and uses twisted liquid crystal alignment. A display mode using liquid crystal alignment parallel to the display surface (parallel to the substrates 4 and 5) and not twisted was used.

  In this embodiment, Δn · d of the liquid crystal layer 1 in the reflective display unit 9 is about 270 nm, and the twist angle (twist angle) of the liquid crystal orientation is 70 degrees. A liquid crystal display device in which Δn · d was about 270 nm and the twist angle (twist angle) of the liquid crystal alignment was 0 ° was produced. As a result, the liquid crystal layer 1 communicated between the reflective display unit 9 and the transmissive display unit 10 is provided, and both the reflective display unit 9 and the transmissive display unit 10 can perform good display without changing the cell gap. A possible liquid crystal display device was obtained.

  Table 5 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the reflective display unit 9 and the transmissive display unit 10 of the liquid crystal display device obtained in this example (that is, The sticking orientations of the polarizing plates 14 and 15 and the retardation compensation plates 16 and 17 and the orientation orientation of the liquid crystal) are shown using a common orientation reference.

  The optical arrangements shown in Table 5 are optical element arrangements on the display surface when the observer observes the display surface, and the phase difference compensation plates constituting the phase difference compensation plates 16 and 17 are: It is described in the order of the actual arrangement from the observer side. Each orientation in Table 5 represents an orientation from a reference orientation arbitrarily taken on the display surface in units of degrees, and the retardation of each phase difference compensator indicates a value for monochromatic light having a wavelength of 550 nm in nm units.

Next, the operation of each optical element in the present embodiment will be described below.
First, a case where no voltage is applied to the liquid crystal layer 1 will be described. In this case, the liquid crystal in the liquid crystal layer 1 is aligned according to the alignment of the substrate interface in contact with the liquid crystal layer 1, that is, the alignment treatment direction of the alignment films 2 and 3 provided on each electrode substrate. For example, in the liquid crystal display device obtained in Example 10 above, when no chiral additive is mixed in the liquid crystal composition, the reflective display unit 9 is twisted to the left by 70 degrees, and the transmissive display unit 10 is not twisted. The twist orientation is 0 degree.

  Therefore, when no voltage is applied to the liquid crystal layer 1, in the reflective display unit 9, when Δn · d of the liquid crystal layer 1 is set to about 270 nm, the liquid crystal layer 1 receives circularly polarized light, It acts to convert it into linearly polarized light and transmit it. Light incident on the liquid crystal layer 1 from the polarizing plate 14 side is converted into circularly polarized light by the phase difference compensation plate 16, further converted from circularly polarized light to linearly polarized light by the liquid crystal layer 1, reaches the reflection film 8 and is reflected. . When the light reflected by the reflective film 8 is linearly polarized light on the reflective film 8, it is converted again into the transmission component of the polarizing plate 14, so that a voltage is applied to the liquid crystal layer 1 in the liquid crystal display device. If not, the display of the reflective display unit 9 is bright.

  Further, when no voltage is applied to the liquid crystal layer 1, in the transmissive display unit 10, when Δn · d of the liquid crystal layer 1 is set to about 250 nm to 270 nm, the liquid crystal layer 1 functions as a half-wave plate. To do. That is, the circularly polarized light incident on the liquid crystal layer 1 becomes circularly polarized light orthogonal to the incident circularly polarized light. For example, when right circularly polarized light (right-handed circularly polarized light) is incident, the right circularly polarized light is left When converted into circularly polarized light (counterclockwise circularly polarized light) and left circularly polarized light is incident, the circularly polarized light is converted into right circularly polarized light. The light incident on the transmissive display unit 10 passes through the polarizing plate 15, is converted into circularly polarized light by the phase difference compensation plate 17, and is incident on the liquid crystal layer 1. In the tenth embodiment, the circularly polarized light incident on the liquid crystal layer 1 from the retardation compensation plate 17 is circularly polarized light whose polarization state is substantially counterclockwise, and this circularly polarized light is incident on the liquid crystal layer 1 to the right. Converted to surrounding circularly polarized light. In the phase difference compensator 16, the clockwise circularly polarized light is converted into linearly polarized light in the transmission axis direction of the polarizing plate 14, and the counterclockwise circularly polarized light is converted into linearly polarized light in the absorption axis direction. When no voltage is applied to the liquid crystal layer 1 in the device, the display of the transmissive display unit 10 is bright.

  Next, a case where a voltage is applied to the liquid crystal layer 1 will be described. When a voltage is applied to the liquid crystal layer 1, the liquid crystal in the liquid crystal layer 1 is aligned vertically to the substrates 4 and 5 according to the voltage regardless of whether it is the reflective display unit 9 or the transmissive display unit 10. Accordingly, the polarization conversion action is weakened accordingly. That is, since the circularly polarized light prepared by the phase difference compensation plates 16 and 17 passes through the liquid crystal layer 1 as it is, dark display is realized in both the reflective display unit 9 and the transmissive display unit 10.

  In Example 10, the retardation compensation plate 17 is a retardation compensation plate having a retardation of 115 nm. In order to realize good circularly polarized light using only the phase difference compensation plate 17, the retardation of the phase difference compensation plate 17 is preferably about 135 nm. However, the liquid crystal layer 1 of the transmissive display unit 10 has a practical voltage. The retardation of the retardation compensation plate 17 is set so that a good contrast can be obtained in consideration of this because the retardation does not disappear completely.

  The phase difference compensation plate 16 has a function of converting the polarization state of light incident on the liquid crystal layer 1 of the reflective display unit 9 into circularly polarized light having a wide wavelength. In the above liquid crystal display device, the liquid crystal layer 1 in the reflective display unit 9 is twisted by 70 degrees and its Δn · d is set to 270 nm. For this reason, in the reflective display unit 9 in the liquid crystal display device described above, the light incident on the liquid crystal layer 1 is circularly polarized light. This circularly polarized light is converted into linearly polarized light by the liquid crystal layer 1 and passes through the liquid crystal layer 1. The reflection film 8 is reached. Then, the light that has been linearly polarized on the reflecting film 8 is reflected by the mirror surface of the reflecting film 8, passes through each optical element in the reverse order, and finally the transmission axis direction of the polarizing plate 14. It becomes a linearly polarized light having an oscillating electric field. For this reason, the reflective display unit 9 performs bright display.

  Moreover, the used liquid crystal composition is mixed with a chiral agent that causes a left-handed twist specific to the alignment of the liquid crystal. This chiral agent changes the helical pitch inherent to the liquid crystal composition in which the chiral agent is mixed depending on the amount of the chiral agent added. For this reason, by adjusting the helical pitch and utilizing the fact that the minimum voltage at which the liquid crystal alignment starts to change with the helical pitch changes, the reflective display unit 9 and the transmissive display unit 10 match the voltage dependence of brightness. Is possible.

  The display characteristics of the liquid crystal display device described in Example 10 manufactured in this manner are shown in FIG. The display characteristics shown in FIG. 19 were measured by the same method as in Example 1. The horizontal axis represents the effective value of the applied voltage, and the vertical axis represents the lightness (reflectance or transmittance).

  In FIG. 19, a curve 331 indicates the voltage dependence of the reflectance of the reflective display unit 9 in the liquid crystal display device obtained in the tenth embodiment, and a curve 332 indicates a transmissive display in the liquid crystal display device obtained in the tenth embodiment. The voltage dependence of the transmittance | permeability of the part 10 is shown.

  As can be seen from FIG. 19, the liquid crystal display device obtained in Example 10 performs bright display when no voltage is applied. In the liquid crystal display device, the reflectivity is increased as the voltage is applied. In addition, display in a so-called normally white (NW) mode in which the transmittance is reduced has been realized. In addition, the liquid crystal display device can set the contrast ratio of the reflective display unit 9 and the transmissive display unit 10 to be substantially the same, and the reflective display unit 9 and the transmissive display unit 10 match the display brightness and darkness. Display with excellent visibility can be realized.

  As described above, as a specific means for changing the liquid crystal alignment between the reflective display unit 9 and the transmissive display unit 10, the twist angle of the liquid crystal layer 1 is different between the reflective display unit 9 and the transmissive display unit 10. The setting is effective for realizing a good display in both the reflective display unit 9 and the transmissive display unit 10.

  In Example 10 described above, in order to change the twist angle of the liquid crystal layer 1 between the reflective display unit 9 and the transmissive display unit 10, rubbing processing in different directions is performed between the reflective display unit 9 and the transmissive display unit 10. The liquid crystal layer 1 of the reflective display unit 9 is twist-oriented, but the liquid crystal layer 1 of the transmissive display unit 10 is a combination that is not twisted. However, the liquid crystal layer is composed of the reflective display unit 9 and the transmissive display unit 10. The means for changing the twist angle of 1 is not particularly limited.

  For example, in addition to the combination shown in Example 10, (1) The liquid crystal layer 1 in the reflective display unit 9 and the liquid crystal layer 1 in the transmissive display unit 10 are both twist-aligned, but the twist angle and direction of the twist are different. Different combinations, or (2) the liquid crystal layer 1 in the reflective display unit 9 is not twisted, but the liquid crystal layer 1 in the transmissive display unit 10 may be twisted, and (3) the substrate 4. 5 may be a combination in which the tilt of the liquid crystal with respect to 5 (so-called pretilt) is different between the reflective display unit 9 and the transmissive display unit 10. Further, (4) the change in the liquid crystal alignment at the substrate interface may be combined with other means of the present invention, and (5) the reflective display unit 9 and the transmissive display unit 10 have different cell gaps, (6) The reflective display unit 9 and the transmissive display unit 10 may have different electric fields.

[Embodiment 5]
In each of the embodiments 2 to 4, the configuration for realizing good reflective display and good transmissive display using the liquid crystal display device in which the liquid crystal is aligned parallel to the substrate has been described. In this embodiment mode, a liquid crystal display device in which the orientation direction of liquid crystal is perpendicular to the substrate will be described as in the first embodiment of the first embodiment mode. However, in this embodiment, a design for performing display using the birefringence or optical rotation (polarization conversion action) of liquid crystal using a polarizing plate without mixing a dichroic dye in the liquid crystal layer is performed. It was. For convenience of explanation, the same reference numerals are given to components having the same functions as those in the first to fourth embodiments, and the description thereof is omitted.

  In the liquid crystal display device according to the present embodiment, a liquid crystal having a negative dielectric anisotropy is used for the liquid crystal layer 1. Further, as the alignment films 2 and 3 sandwiching the liquid crystal layer 1, a vertical alignment film for vertically aligning the liquid crystal is used. In this case, the liquid crystal molecules are aligned substantially perpendicular to the substrates 4 and 5 (display surface) when no voltage is applied to the liquid crystal layer 1. A polarization conversion action is produced on light that is aligned with an inclination from the direction and passes in the normal direction of the layered liquid crystal layer 1.

  The difference between the liquid crystal display device using the alignment films 2 and 3 in which the liquid crystal is aligned parallel to the substrate and the liquid crystal display device according to the present embodiment is that no voltage is applied to the liquid crystal display device according to the present embodiment. Even in this case, the liquid crystal is aligned in the normal direction of the substrates 4 and 5 up to the interface layer with the electrode substrate in the liquid crystal layer 1. Therefore, in order to use this effectively, in this embodiment, an NB (normally black) mode in which black display is performed when no voltage is applied is used for display. Specifically, the reflective display unit 9 performs display by causing circularly polarized light to enter the liquid crystal layer 1. Further, in the transmissive display unit 10, the phase difference compensation plate 16 that is also used for reflective display acts on the polarization of the light emitted from the liquid crystal layer 1, so that the liquid crystal layer 1 is connected to the reflective display unit 9 and the transmissive display unit. 10 is driven by a pair of electrodes that are electrically connected to each other, and at the same time, in order to realize a dark display, the liquid crystal layer 1 is also aligned in the vertical direction with respect to the substrates 4 and 5 in the transmissive display. Circularly polarized light is incident on the layer 1. For this reason, in the combination of the polarizing plates 14 and 15 and the phase difference compensation plates 16 and 17, the phase difference disposed on the side closer to the liquid crystal layer 1 among the plurality of phase difference compensation plates constituting the phase difference compensation plate 17. The retardation of the compensation plate is set to 135 nm. Thereby, in this Embodiment, favorable NB display is realizable.

  Next, setting of the liquid crystal layer 1 that gives a good bright display in the above-described combination of the polarizing plates 14 and 15 and the retardation compensation plates 16 and 17 will be described.

  In the present embodiment, as described above, the liquid crystal layer 1 is aligned with an inclination from the normal direction of the substrates 4 and 5 with the application of a voltage. The liquid crystal layer 1 acts on the reflective display unit 9 so as to convert circularly polarized light into linearly polarized light when the voltage is sufficiently applied to the liquid crystal layer 1, and the transmissive display unit 10. It is desirable to act so as to convert circularly polarized light into reverse circularly polarized light. When the liquid crystal layer 1 exhibits the above conversion effect, a good bright display can be realized.

  In order for the liquid crystal layer 1 to exhibit the above conversion effect, for example, it is desirable to align the alignment films 2 and 3 so as not to cause twist in the liquid crystal and to use no chiral additive in the liquid crystal composition. That is, the retardation of the liquid crystal layer 1 changes by λ / 4 in the reflective display unit 9 and changes by λ / 2 in the transmissive display unit 10 when the wavelength of the incident light is λ by applying a voltage to the liquid crystal layer 1. It is desirable that the liquid crystal layer 1 is set in such a manner.

  When the thickness of the liquid crystal layer 1 in the reflective display unit 9 and the layer thickness of the liquid crystal layer 1 in the transmissive display unit 10 are set to be different from each other, the liquid crystal layer 1 is formed so that the liquid crystal layer 1 performs the above-described conversion action. Setting as described above is easy.

  Hereinafter, the liquid crystal display device according to the present embodiment will be described with specific examples. However, the liquid crystal display device according to the present embodiment is not limited to the following examples.

Example 11
In this example, a liquid crystal cell for liquid crystal injection having different liquid crystal layer thicknesses in the reflective display unit 9 and the transmissive display unit 10 was manufactured by the same method as the method for manufacturing the liquid crystal cell for liquid crystal injection in Example 1. As the alignment films 2 and 3, a vertical alignment film having an action of aligning the liquid crystal vertically with respect to the substrates 4 and 5 was used. The alignment films 2 and 3 were subjected to alignment treatment by rubbing so that the liquid crystal was aligned with a slight inclination from the normal direction (vertical direction) of the substrates 4 and 5.

  However, in this embodiment, the liquid crystal layer thickness (d) in the reflective display portion 9 is 3 μm, the liquid crystal layer thickness (d) in the transmissive display portion 10 is 6 μm, and the liquid crystal material has a refractive index difference (Δn) of 0.06. The liquid crystal layer 1 is formed using a liquid crystal having negative dielectric anisotropy, and the retardation compensation plates 16 and 17 and the polarizing plates 14 and 15 are pasted outside the electrode substrates in the liquid crystal cell. Thus, a liquid crystal display device was produced. The phase difference compensation plate 16 and the phase difference compensation plate 17 are each composed of two phase difference compensation plates.

  Table 6 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the reflective display unit 9 and the transmissive display unit 10 of the liquid crystal display device obtained in this example (that is, The sticking orientations of the polarizing plates 14 and 15 and the retardation compensation plates 16 and 17 and the orientation orientation of the liquid crystal) are shown using a common orientation reference.

  The optical arrangements shown in Table 6 are optical element arrangements on the display surface when the observer observes the display surface, and the phase difference compensation plates constituting the phase difference compensation plates 16 and 17 are: It is described in the order of the actual arrangement from the observer side. Each orientation in Table 6 represents an orientation from a reference orientation arbitrarily taken on the display surface in units of degrees, and the retardation of each retardation compensation plate indicates a value for monochromatic light having a wavelength of 550 nm in nm units.

  FIG. 20 shows the display characteristics of the liquid crystal display device described in this example, manufactured as described above. The display characteristics shown in FIG. 20 are measured by the same method as in Example 1. The horizontal axis indicates the effective value of the applied voltage, and the vertical axis indicates the brightness (reflectance or transmittance).

  In FIG. 20, a curve 341 shows the voltage dependence of the reflectance of the reflective display unit 9 in the liquid crystal display device obtained in Example 11, and a curve 342 shows a transmissive display in the liquid crystal display device obtained in Example 11. The voltage dependence of the transmittance | permeability of the part 10 is shown.

  As can be seen from FIG. 20, the liquid crystal display device obtained in Example 11 performs dark display when no voltage is applied. In the liquid crystal display device, the reflectance is increased as the voltage is applied. In addition, display in the so-called NB mode in which the transmittance increases is realized. In addition, the liquid crystal display device can set the contrast ratio of the reflective display unit 9 and the transmissive display unit 10 to be substantially the same, and the reflective display unit 9 and the transmissive display unit 10 match the display brightness and darkness. Display with excellent visibility can be realized.

  As described above, according to the present embodiment, in the liquid crystal display device according to the present invention in which the reflective display unit 9 and the transmissive display unit 10 simultaneously realize different liquid crystal orientations, the reflective display unit 9 or the transmissive display unit 10. By using an alignment means (vertical alignment film) for aligning the liquid crystal perpendicularly to the substrate surface in contact with the liquid crystal (liquid crystal layer 1), at least one of the reflective display unit 9 and the transmissive display unit 10 is good. It has been confirmed that a transflective liquid crystal display device capable of performing accurate display is realized.

[Embodiment 6]
In the present embodiment, when display is performed by changing the liquid crystal alignment with a voltage, the alignment state of the liquid crystal is maintained parallel to the display surface (substrate) in at least one of the reflective display portion and the transmissive display portion. A liquid crystal display device that performs display while changing the orientation direction of the liquid crystal will be described. That is, in the liquid crystal display device according to the present embodiment, the liquid crystal molecules rotate in parallel to the display surface (substrate) by applying a voltage in at least one of the reflective display portion and the transmissive display portion. .

  Hereinafter, the liquid crystal display device according to the present embodiment will be described using specific examples. However, the liquid crystal display device according to the present embodiment is not limited to the following examples. For convenience of explanation, components having the same functions as those in the first to fifth embodiments are denoted by the same reference numerals and description thereof is omitted.

Example 12
In this embodiment, an IPS (in-plane switching) mode, which is used to realize a wide viewing angle in a transmissive liquid crystal display device, is used for a transflective liquid crystal. A liquid crystal display device having an optical switch function by rotating liquid crystal molecules parallel to the substrate by an electric field will be described below with reference to FIGS. 21 (a) and 21 (b).

  Conventionally, the IPS mode itself has been used in the field of transmissive liquid crystal display devices, but the change in liquid crystal alignment is insufficient for transmissive display on the comb electrode used when the IPS mode is used. The liquid crystal alignment on the electrode did not contribute to the display, and a good display could not be realized. However, according to the present embodiment, a reflective display is realized in a region on the comb-shaped wiring that cannot be used in the conventional IPS system, and a transflective liquid crystal display device with high light utilization efficiency can be obtained.

  FIG. 21A is a cross-sectional view of a main part when no voltage is applied to the liquid crystal display device according to this example, and FIG. 21B is a diagram when voltage is applied to the liquid crystal display device shown in FIG. It is principal part sectional drawing. 21 (a) and 21 (b), the liquid crystal cell in the liquid crystal display device is a surface perpendicular to the direction in which the electrode wiring (terminal) of the comb-shaped electrode provided in the liquid crystal cell extends. The cross section when cut is shown.

  In the liquid crystal display device shown in FIG. 21A and FIG. 21B, the liquid crystal layer 1 includes a light-transmitting substrate 51 and a light-reflective comb-shaped electrode 53 (display content rewriting means, voltage applying means, (Orientation mechanism) is sandwiched between the substrate 54 having light reflectivity, and further, on the outside of the substrate 51 (that is, on the side opposite to the surface facing the substrate 54), the retardation compensation plate 16 and the polarizing plate. 14, and a configuration in which the retardation compensation plate 17 and the polarizing plate 15 are provided outside the substrate 54 (that is, on the side opposite to the surface facing the substrate 51). In this embodiment, the phase difference compensation plate 16 is composed of one phase difference compensation plate, and the phase difference compensation plate 17 is composed of two phase difference compensation plates.

  Also in this embodiment, the liquid crystal display device includes an insulating photosensitive resin on the glass substrate 52 in one substrate 54 (electrode substrate) of the pair of substrates provided with the liquid crystal layer 1 interposed therebetween. The insulating film 11 is applied so that the photosensitive resin does not remain in the transmissive display portion 10 and the photosensitive resin is formed in a predetermined layer thickness in the reflective display portion 9 by application by spin coating and further irradiation with an ultraviolet light mask. (Orientation mechanism) is patterned. Thereby, the layer thickness of the liquid crystal layer 1 in the transmissive display unit 10 is set to be thinner than the layer thickness of the liquid crystal layer 1 in the reflective display unit 9.

  In the liquid crystal display device according to this example, a comb-shaped electrode 53 (orientation mechanism) having light reflectivity is formed on the glass substrate 52 so as to cover the insulating film 11. The comb electrode 53 is a reflective pixel electrode that doubles as a liquid crystal driving electrode that drives the liquid crystal layer 1 and a reflective film (reflecting means), and is made of a metal having a high light reflectance.

  In the liquid crystal display device, in the transmissive display unit 10, the alignment state of the liquid crystal molecules 1 a is changed by the electric field applied by the comb electrode 53. In the reflective display unit 9, the liquid crystal layer 1 is driven by the electric field generated by the comb electrode 53, and the reflective action of the comb electrode 53 is used for display.

  In this embodiment, the wiring of the comb-shaped electrode 53 is used as the reflecting means. However, the comb-shaped electrode 53 may have a concavo-convex structure on the surface thereof in order to impart light scattering properties. In addition, a film having light scattering properties may be further formed in a region facing the comb-shaped electrode 53 outside the glass substrate 51.

  In the liquid crystal display device shown in FIGS. 21A and 21B, different potentials are applied to the adjacent comb electrodes 53a and 53b, and an electric field is generated between the comb electrodes 53a and 53b. As shown in FIG. 21B, the transmissive display unit 10 corresponds to a gap between the comb-shaped electrodes 53a and 53b. In this portion, the liquid crystal orientation is aligned by the above-mentioned comb-shaped electrode pair (comb-shaped electrodes 53a and 53b). Greatly changes while maintaining a direction parallel to the glass substrate 52. The reflective display unit 9 corresponds to the portion directly above the comb-shaped electrode 53 (comb-shaped electrodes 53a and 53b). In this portion, the liquid crystal alignment is not only the change of the orientation along the plane of the glass substrate 52 but also the glass substrate 52. It changes to the direction perpendicular to. This is because, as shown in FIG. 21B, in the transmissive display unit 10, the lines of electric force (indicated by broken lines in the figure) extend substantially parallel to the glass substrate 52, whereas the reflective display unit 9 This is because the lines of electric force have a component perpendicular to the glass substrate 52.

  Table 7 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the reflective display unit 9 and the transmissive display unit 10 of the liquid crystal display device according to this example (that is, the polarizing plate). 14 and 15 and the phase difference compensation plates 16 and 17 and the orientation of the liquid crystal) are shown using a common orientation standard.

  The optical arrangement shown in Table 7 is the arrangement of each optical element on the display surface when the observer observes the display surface. Each phase difference compensation plate constituting the phase difference compensation plate 17 is an observer. It is described in the order of actual arrangement from the side.

  Further, the orientation direction of the liquid crystal layer 1 (major axis orientation direction of the liquid crystal molecules 1a) is equal to the rubbing treatment direction on the surface of the substrate 51 on the substrate 51 side, and equal to the rubbing treatment direction on the surface of the substrate 54 on the substrate 54 side. Hereinafter, the orientation orientation of the liquid crystal layer 1 on the substrate 51 side is referred to as the substrate 51 orientation orientation, and the orientation orientation of the liquid crystal layer 1 on the substrate 54 side is referred to as the substrate 54 orientation orientation.

  Each orientation in Table 7 represents an orientation from a reference orientation arbitrarily taken on the display surface in units of degrees, and the retardation of each retardation compensation plate indicates a value for monochromatic light having a wavelength of 550 nm in nm units.

  Here, the direction in which the electrode wiring (terminal) of the comb-shaped electrode 53 extends is 65 degrees azimuth, and the liquid crystal alignment is 75 degrees between the transmissive display unit 10 and the reflective display unit 9 with the application of voltage. It changed so that the liquid crystal molecule 1a facing the orientation had an orientation larger than the 75-degree orientation. In the liquid crystal display device, Δn · d of the liquid crystal layer 1 in the reflective display unit 9 is set to about 130 nm, and Δn · d of the liquid crystal layer 1 in the transmissive display unit 10 is set to about 240 nm.

  In the liquid crystal display device set as described above, both the reflective display unit 9 and the transmissive display unit 10 are darkly displayed when no voltage is applied to the liquid crystal layer 1. When a voltage is applied to the liquid crystal layer 1 from this state, the orientation direction of the liquid crystal molecules 1a changes so as to deviate from the orientation in which the electrode wiring (terminal) of the comb electrode 53 extends (65 degrees orientation in the above setting). . Therefore, in the above liquid crystal display device, bright display is realized by changing the orientation direction of the liquid crystal when a voltage is applied.

  The display characteristics of the liquid crystal display device according to this example manufactured in this way are shown in FIG. The display characteristics shown in FIG. 22 were measured by the same method as in Example 1. The horizontal axis represents the effective value of the applied voltage, and the vertical axis represents the lightness (reflectance or transmittance).

  In FIG. 22, a curve 351 indicates the voltage dependency of the reflectance of the reflective display unit 9 in the liquid crystal display device obtained in Example 12, and a curve 352 indicates a transmissive display in the liquid crystal display device obtained in Example 12. The voltage dependence of the transmittance | permeability of the part 10 is shown. Although the reflective display unit 9 has different optical characteristics depending on the position on the comb-shaped electrode 53, the optical characteristics of representative portions are shown here.

  As can be seen from FIG. 22, in the liquid crystal display device obtained in Example 12, both the reflective display portion 9 and the transmissive display portion 10 perform dark display when no voltage is applied. In the display device, the reflectance and transmittance increase with application of voltage. Further, when the applied voltage is 2V, the reflectance of the reflective display unit 9 and the transmittance of the transmissive display unit 10 are both 3%, and when the applied voltage is 5V, the reflectance of the reflective display unit 9 is 35%. The transmittance of the display unit 10 was 38%. Therefore, according to the above-described liquid crystal display device, both the brightness of the bright display and the contrast ratio can be achieved for both the reflective display unit 9 and the transmissive display unit 10, and a display with excellent visibility can be achieved. Can be realized. Further, according to the liquid crystal display device described above, since the contrast ratio in the transmissive display unit 10 exceeds the contrast ratio in the reflective display unit 9, display quality can be further improved and good display can be performed.

  As described above, according to the twelfth embodiment, a reflective display is realized in a region on the comb-shaped wiring 53 that cannot be used for display by the conventional IPS system, and a transflective liquid crystal display device with high light utilization efficiency is achieved. Confirmed that you can get.

  In this embodiment, as a method for realizing the above-described liquid crystal alignment, in addition to a method using a nematic liquid crystal as in the above-described IPS mode, a method using a ferroelectric liquid crystal display mode or an antiferroelectric liquid crystal A method using a display mode can be used.

  Therefore, in Example 13 below, a liquid crystal display device using a ferroelectric liquid crystal display mode for display will be described as another liquid crystal display device that realizes the liquid crystal alignment described above.

Example 13
In this example, in the liquid crystal display device shown in Example 1, surface-stabilized ferroelectric liquid crystal is used as the liquid crystal material, and the liquid crystal layer thickness (d) is 1.4 μm in the transmissive display unit 10 and in the reflective display unit 9. The thickness is set to 0.7 μm, and Δn · d of the liquid crystal layer 1 is set to about 130 nm for the reflective display unit 9 and about 260 nm for the transmissive display unit 10, and the electrode 7 corresponding to the reflective display unit 9 is set. A liquid crystal cell designed in the same manner as the liquid crystal cell shown in Example 1 was manufactured except that the reflective electrode was used in the region corresponding to the reflective display unit 9 as an electrode instead of forming the reflective film 8 thereon.

  Specifically, on the substrate 5 (glass substrate), no photosensitive resin remains in the transmissive display unit 10, and the reflective display unit 9 is insulated so that the photosensitive resin is formed with a layer thickness of 0.7 μm. The film 11 was patterned, a reflective electrode was produced in the insulating film 11 formation part (reflection display part 9), and a transparent electrode was produced in the insulating film 11 non-formation part (transmission display part 10). And the alignment film 3 was formed on the said electrode formation surface in this board | substrate 5, and the electrode substrate was produced by performing the alignment process by rubbing. The configuration of the electrode substrate (counter substrate) disposed to face the electrode substrate is the same as that described in the first embodiment. Then, a ferroelectric liquid crystal composition containing the surface-stabilized ferroelectric liquid crystal is introduced between both the electrode substrates to produce a liquid crystal cell, and the retardation compensation plate 16 is provided outside each electrode substrate in the liquid crystal cell. 17 and polarizing plates 14 and 15 were pasted to prepare a liquid crystal display device. In this embodiment, the phase difference compensation plate 16 is composed of one phase difference compensation plate, and the phase difference compensation plate 17 is composed of two phase difference compensation plates.

  Table 8 shows the optical arrangement of the polarizing plates 14 and 15, the retardation compensation plates 16 and 17, and the liquid crystal layer 1 in the liquid crystal display device obtained in this example (that is, the polarizing plates 14 and 15 and the retardation compensation plate). 16 and 17 sticking directions, and bright and dark liquid crystal alignment orientations) are shown using a common orientation standard.

  The optical arrangement shown in Table 8 is the arrangement of each optical element on the display surface when the observer observes the display surface. Each phase difference compensation plate constituting the phase difference compensation plate 17 is an observer. It is described in the order of actual arrangement from the side. Each azimuth in Table 8 represents an azimuth from a reference azimuth arbitrarily taken on the display surface in units of degrees, and the retardation of each retardation compensation plate represents a value for monochromatic light having a wavelength of 550 nm in nm.

  The liquid crystal display device thus manufactured was a liquid crystal display device having good brightness and contrast ratio in both the reflective display unit 9 and the transmissive display unit 10.

  As described above, if the liquid crystal display device realizes different liquid crystal alignments and liquid crystal layer thicknesses simultaneously in the reflective display unit 9 and the transmissive display unit 10, the direction of change in the alignment of the liquid crystal layer 1 due to the application of voltage is the liquid crystal layer plane. Even if it changes within the range, a good display can be obtained as the transflective liquid crystal display device of the present invention. When the liquid crystal display device uses the IPS mode, the light use efficiency can be improved as compared with the conventional transmission type liquid crystal display device using the IPS mode. The liquid crystal display device according to the present embodiment can also be used in a mode such as a ferroelectric liquid crystal.

[Embodiment 7]
In the present embodiment, a specific element substrate and color filter substrate of active matrix driving that enable the configuration of the liquid crystal display device according to the present invention will be described.

  When the liquid crystal display device according to the present invention is manufactured for the purpose of image display, the ratio between the transmissive display unit and the reflective display unit depends on the frequency of use when used for transmissive display and when used for reflective display. It is practically important to design.

  That is, in the first usage pattern, the transmitted light from the illumination device (backlight) as the background illumination means is used for the main display, and the reflective display unit is washed out, as in the transmissive liquid crystal display device currently used. Is a usage pattern (hereinafter abbreviated as “transparent main transflective”).

  The second usage pattern is a usage pattern in which a reflective display is mainly used. A backlight with high power consumption is often turned off depending on the situation to reduce power consumption and the surrounding illumination light is weak. When the display content cannot be confirmed by only the reflective display, the backlight is turned on and used (hereinafter referred to as “reflective main body transflective”).

  In such two types of usage, since the main display is performed in transmissive display or reflective display, the ratio of the display area between the transmissive display portion and the reflective display portion, or in the case of color display is different. Each color filter has a different color design.

  Therefore, first, a transmission-based semi-transmission type liquid crystal display device mainly including transmission will be described below by taking a liquid crystal display device using a TFT element which is one of active matrix methods for display as an example. For convenience of explanation, components having the same functions as those in the first to sixth embodiments are denoted by the same reference numerals and description thereof is omitted.

  First, a substrate structure of a transmissive main body transflective liquid crystal display device using a TFT element for display will be described below with reference to FIGS.

  FIG. 23A is a plan view of a principal part of a TFT element substrate for realizing the transmission-dominant semi-transmissive liquid crystal display device according to the seventh embodiment, and FIG. 23B is a plan view of FIG. FIG. 23C is a diagram showing the drive electrode 19 of the reflective display section 9 (see FIGS. 1, 4, 24, and 25) in the TFT element substrate shown in FIG. 23, and FIG. 23C is a diagram showing the TFT shown in FIG. It is a figure which shows the transparent pixel electrode 20 in an element substrate.

  24 is a cross-sectional view taken along the line AA ′ of the TFT element substrate shown in FIG. 23 (a). More specifically, the TFT element substrate shown in FIG. 19 is a diagram showing a cross-section passing through the auxiliary capacitor portion 26 through 19 and the transparent pixel electrode 20. Further, FIG. 25 is a cross-sectional view taken along line B-B ′ of the TFT element substrate shown in FIG. 23A, and shows a cross-sectional structure of a boundary portion between adjacent pixels.

  As shown in FIGS. 23A, 24, and 25, the pixel electrode 18 that drives the liquid crystal layer 1 (see FIGS. 1 and 4) includes a drive electrode 19 (display content rewriting means, Voltage application means) and transparent pixel electrodes 20 (display content rewriting means, voltage application means) made of ITO. The drive electrode 19 may be a reflective electrode having reflectivity. Further, the drive electrode 19 and the transparent pixel electrode 20 may be electrically connected to each other when the liquid crystal display system used for display is a display system that does not show inversion of light and dark even if display is performed with the same voltage. .

  The drive electrode 19 and the transparent pixel electrode 20 are connected to a drain terminal 22 of a TFT element 21 that controls a voltage used for display in units of pixels. The drive electrode 19 is provided with a transmissive display opening 19a. When the drive electrode 19 is a reflective electrode, the transmissive display opening 19a is formed as a transmissive display unit 10 in a transmissive display. Used for.

  Under the drive electrode 19, the TFT element 21, the wiring 23 and the wiring 24, the auxiliary capacitance portion 26 and the auxiliary capacitance line 27 are arranged. However, since these constituent elements are made of a light-shielding material such as metal, in the present embodiment, the TFT element substrate is manufactured so that these constituent elements are not arranged in the transmissive display opening 19a. is doing. In FIG. 23A, the drive electrode 19 is indicated by a two-dot chain line.

  Further, as shown in FIG. 24, a main part of the drive electrode 19 of the reflective display unit 9 that applies a voltage to the reflective display unit 9 constituting the pixel electrode 18 is a wiring for driving the TFT element 21. 23 and 24 and the surface of the substrate 19 on which the TFT element 21 is formed (TFT element substrate surface) are separated by an organic insulating film 25. The organic insulating film 25 is formed of an organic insulating material having a low dielectric constant and has a thickness of 3 μm. This is because the parasitic capacitance component formed between the wiring 23 serving as the gate wiring of the TFT element 21 and the wiring 24 serving as the source wiring of the TFT element 21 and the pixel electrode 18 controls the opening / closing operation of the TFT element 21. This is to prevent the signal waveform and the source signal waveform from being delayed or distorted, and to enable dot matrix display with high resolution, and at the same time, the reflective display unit 9 and the transmissive display in the liquid crystal display device according to the present embodiment. This is to improve the optical characteristics of the portion 10.

  The pixel electrode 18 is connected to the drain terminal 22 of the TFT element 21. The drain terminal 22 is an n + amorphous silicon layer doped n-type and functions as a drain electrode of the TFT element 21. In the TFT element substrate according to the present embodiment, the ITO layer disposed so as to be in contact with the drain terminal 22 is used as the transparent pixel electrode 20 and further patterned so as to cover a part of the transparent pixel electrode 20. On the organic insulating film 25 thus formed, the drive electrode 19 of the reflective display unit 9 is formed. That is, in the transmissive main body transflective liquid crystal display device using the TFT element substrate shown in FIG. 24, the transparent pixel electrode 20 used for transmissive display and the drive electrode 19 used for reflective display are composed of the organic insulating film 25. Are electrically connected at the pattern boundary. Moreover, as shown in FIGS. 24 and 25, the driving electrode 19 of the reflective display unit 9 may be provided with smooth irregularities on the surface thereof for the purpose of preventing the display surface from being mirrored.

  Further, as shown in FIG. 25, the organic insulating film 25 is formed so as to cover the wiring 24 connected to the source terminal 28 of the TFT element 21 at the boundary portion between adjacent pixels in the TFT element substrate, A drive electrode 19 of the reflective display unit 9 is formed on the organic insulating film 25.

  In the TFT element substrate thus manufactured, the pixel electrode 18 and the wirings 23 and 24 are formed through the organic insulating film 25 by appropriately setting the relationship between the film thickness of the organic insulating film 25 and the dielectric constant. Since the parasitic capacitance component can be suppressed, the drive electrode 19 of the reflective display unit 9 can be extended to the position immediately above the wirings 23 and 24 as shown in FIG. In this case, the gap between adjacent pixel electrodes 18 can be designed to be narrow, and the leakage electric field from the wirings 23 and 24 to the liquid crystal layer 1 is reduced in the pixel gap, so that the orientation of the liquid crystal layer 1 is not easily disturbed. . Therefore, by appropriately setting the relationship between the film thickness of the organic insulating film 25 and the dielectric constant, the liquid crystal orientation of the liquid crystal layer 1 can be controlled to the vicinity of the boundary between the pixel electrodes 18, and so-called transmission with a high aperture ratio. A TFT element substrate of a main transflective liquid crystal display device can be manufactured. In the present embodiment, the organic insulating film 25 is formed of an organic insulating material having a relative dielectric constant of 3.5 so as to have a film thickness of 3 μm.

  As described above, in this embodiment, a TFT element substrate in which the area that can be used for transmissive display accounts for 45% of the area of the entire pixel and the area that can be used for reflective display accounts for 38% of the entire pixel is manufactured. The TFT element substrate ensures a substantially equivalent ratio of the transmissive display unit 10 as compared with the aperture ratio of the transmissive display unit of a transmissive TFT liquid crystal display device that has been widely used in the past being around 50%. In addition, since the display light intensity of the reflective display unit 9 is added to the transmissive display light for display, the TFT element substrate of the transmissive main transflective liquid crystal display device with high light use efficiency that can be used for display is provided. It can be said.

  In this way, high light utilization efficiency can be realized in this embodiment because the reflective display unit 9 does not transmit light such as the TFT element 21, the wirings 23 and 24, the auxiliary capacitor unit 26, and the auxiliary capacitor line 27. This is because the constituent elements can be arranged, and the light used for the liquid crystal display is not impaired by these constituent elements.

  Next, a color filter substrate used to face the TFT element substrate thus manufactured will be described below with reference to FIGS. 26 (a) and 26 (b).

  As shown in FIGS. 26 (a) and 26 (b), three color filters 61R, 61G, and 61B of red (R), green (G), and blue (B) are formed on the color filter substrate. Has been. Each of the three color filters 61R, 61G, and 61B is formed of a photosensitive resin in which a pigment is dispersed, and is formed on the glass substrate 62 by a photolithography technique so as to have a stripe shape matching the pixels of the TFT element substrate. It is a colored layer formed in a planar shape, and is formed separately for each color.

  Further, on the surface of the glass substrate 62 where the color filters 61R, 61G and 61B are formed, as shown in FIG. 26B, the color filters 61R, 61G and 61B are covered with a transparent acrylic resin so as to cover them. A layer 501 is provided thereon, and a 140 nm thick ITO is used as a counter electrode 502 (display content rewriting means, voltage application means) of the pixel electrode 18 in the TFT element substrate, using a shielding mask that covers other than a predetermined region. The film is formed by sputtering. Accordingly, the color filters 61R, 61G, and 61B are separated by a transparent region for each color.

  The positional relationship of the overlapping of the color filter substrate and the TFT element substrate is as shown in FIG. 26A, and the transmissive display opening 19a of the drive electrode 19 formed in the reflective display portion 9 of the TFT element substrate. (That is, the transmissive display unit 10) is completely covered with the R, G, B stripe-shaped color filters 61R, 61G, 61B, while the reflective display unit 9 has the color filters 61R, 61G, 61 in the drive electrode 19. Only the portion of 61B in the extending direction is covered with the color filters 61R, 61G, 61B, and the transparent region between the color filters 61R, 61G, 61B is the other region of the drive electrode 19 formed in the reflective display section 9 ( The color filters 61R, 61G, and 61B are disposed so as to face each other in the direction other than the extending direction.

  FIG. 27 shows the arrangement of the reflective display unit 9 and the transmissive display unit 10 and the color filters 61R, 61G, and 61B in combination with the color filter substrate and the TFT element substrate. In FIG. 27, the color filter substrate and the TFT element substrate are overlapped at a position where they are used as a liquid crystal display device, and the color filter substrate and the TFT element substrate are cut at the position CC ′ in FIG. FIG. 27 is a cross-sectional view taken along the line CC ′ of the main part of the liquid crystal display device illustrated in FIG.

  Thus, each of the color filters 61R, 61G, and 61B of R, G, and B is formed in the transmissive display unit 10, and the direction other than the extending direction of the color filters 61R, 61G, and 61B in the reflective display unit 9 is formed. This portion corresponds to the transparent region between the color filters 61R, 61G, and 61B.

  As a result, color filters 61R, 61G, and 61B similar to the color filters 61R, 61G, and 61B used for transmissive display act on a part of the reflective display unit 9, and the remaining reflective display unit 9 has the color filters 61R, 61R, and 61B. 61G and 61B do not work. As a result, color display (color display) is possible even for reflective display, and the reflectance necessary for the reflective display unit can be ensured.

  The transmitted colors appearing in the light transmitted through the color filter substrate manufactured as shown in FIGS. 26 (a) and 26 (b) are transmissive liquid crystal displays for each of the R, G, and B pixels. It may have the same color as the transmitted colors of R, G, and B used in the apparatus, and may be appropriately adjusted according to the application.

  In the combination of the TFT element substrate and the color filter substrate shown in FIG. 26A and FIG. 27, the transmissive display unit 10 performs the display with the light passing through the color filters 61R, 61G, and 61B, and the reflective display. The part 9 performs display using the color filters 61R, 61G, and 61B similar to those of the transmissive display unit 10, and performs display without using the color filters 61R, 61G, and 61B in the remaining part. . This is because if the color filters 61R, 61G, 61B of the transmissive display unit 10 are used as they are in the reflective display unit 9, the lightness is insufficient. Therefore, a portion where the color filters 61R, 61G, 61B are not used is provided in the reflective display unit 9. This is because the purpose is to compensate.

  Further, as in the present embodiment, the reflective display unit 9 includes the color filters 61R, 61G, and 61B in the transmissive display unit 10 in consideration that the display light passes through the color filters 61R, 61G, and 61B twice. Color filters 61R, 61G, and 61B having higher brightness may be provided.

  In the present embodiment, at least the color filters 61R, 61G, and 61B are formed in the transmissive display unit 10 and the reflective display unit 9 is not provided with the color filters 61R, 61G, and 61B in accordance with the purpose of use. The color filter 61R / 61G / 61B may be used only in the transmissive display unit 10 and the color filter 61R / 61G / 61B may not be provided in the reflective display unit 9.

  When the reflective display unit 9 is not provided with the color filters 61R, 61G, and 61B, the display voltage signal necessary for transmissive display is a signal suitable for color display, and the display voltage signal necessary for reflective display is displayed in black and white. It is a signal suitable for. For this reason, for example, the ratio that each pixel of R, G, and B contributes to the brightness is proportional to the luminous transmittance (Y value) of each color in the transmissive display unit 10, but each pixel in the reflective display unit 9 This causes a driving problem such that they are completely equal.

  That is, for example, when the brightness of the display is compared between when only the B pixel is brightly displayed and when only the G pixel is brightly displayed, the transmissive display in which the color filters 61R, 61G, and 61B are arranged is provided. The brightness in consideration of the luminous transmittance is different in the part 10, but the brightness is the same in the reflective display part 9 in which the color filters 61R, 61G, 61B are not arranged.

  As a method for preventing such a problem, the area of the area where the color display of the reflective display unit 9 is not performed according to the Y values of the R, G, and B colors of the color filters 61R, 61G, and 61B used for transmissive display. Is changed for each of R, G, and B pixels. Thereby, the contribution to the brightness from the monochrome display of the reflective display unit 9 in each of the R, G, and B pixels is adjusted by changing the area of the reflective display unit 9, and the black and white based on the area of the reflective display unit 9 is adjusted. The brightness of the display can be reflected in the display brightness of each color.

  Further, the same effect can be obtained by designing the color filter coverage of the reflective display unit 9 so as to be in the order of G, R, and B in ascending order. According to this method, there is also an advantage that slight green coloring seen in a normal polarizing plate can be corrected. In addition, when the color filter substrate and the TFT element substrate are arranged so as to overlap each other as shown in FIG. 26A, there is an advantage that the positional accuracy of the overlap between the TFT element substrate and the color filter substrate can be relatively large. . This is because the color filter non-formation portion of the reflective display portion 9 exists on both sides of one pixel, and when one of them increases due to the position shift, the other decreases.

  When the TFT element substrate and the color filter substrate as described above are used, when transmissive display is performed, a conventional transmissive display TFT liquid crystal display device can be obtained by using an illumination device (backlight) as background illumination means. In addition, even if the ambient light is very strong, the reflected light is displayed close to the display content of the transmissive display. A high-resolution color liquid crystal display device free from parallax and having no washout even when strong can be realized.

  Next, when the configuration of the TFT element substrate and the color filter substrate is changed and the main usage is used as a liquid crystal display device with low power consumption by using reflected light of ambient light for display, and the intensity of ambient light is not sufficient A substrate structure of a reflection-based transflective liquid crystal display device that uses transmissive display only for the above will be described below with reference to FIGS. 28, 29 (a), and 29 (b).

  FIG. 28 is a plan view of a main part of a TFT element substrate for realizing a reflection-based transflective liquid crystal display device according to the seventh embodiment, and shows the configuration of the TFT element substrate mainly composed of reflection. . In FIG. 28, the drive electrode 19 is indicated by a two-dot chain line.

  As shown in FIG. 28, the reflection-dominant transflective liquid crystal display device is configured so that the size of the transmissive display opening 19a and the size of the transparent pixel electrode 20 in the drive electrode 19 are the same. The liquid crystal display device has the same configuration as that of the transmissive main body transflective liquid crystal display device except that it is set smaller than that of the TFT element substrate used in the display device.

  That is, also in the reflection-based transflective liquid crystal display device, the pixel electrode 18 that drives the liquid crystal layer 1 (see FIGS. 1 and 4) is connected to the drive electrode 19 of the reflective display unit 9 as shown in FIG. The drive electrode 19 and the transparent pixel electrode 20 are connected to a drain terminal 22 of a TFT element 21 for controlling a voltage used for display in units of pixels. The drive electrode 19 has a transmissive display opening 19a. When the drive electrode 19 is a reflective electrode, the transmissive display opening 19a is formed in the transmissive display section 10 (FIG. 24, FIG. 24). As shown in FIG. 25 and FIG. 27, it is used for transmissive display.

  Further, the TFT element 21, the wiring 23 and the wiring 24, the auxiliary capacitance portion 26, and the auxiliary capacitance line 27 are disposed below the drive electrode 19, and these components are not disposed in the transmissive display opening 19a. Are arranged as follows.

  However, the TFT element substrate shown in FIG. 28 has a smaller proportion of the transmissive display portion 10 than the TFT element substrate used in the transmissive main body semi-transmissive liquid crystal display device shown in FIGS. The ratio of the reflective display unit 9 (see FIGS. 24, 25, and 27) is set to be large.

  Thus, in the present embodiment, as a TFT element substrate for a reflection-based transflective liquid crystal display device, the area that can be used for transmissive display is 13% of the area of the entire pixel, and the area that can be used for reflective display is the pixel. A TFT element substrate occupying 70% of the whole was produced.

  The ratio of the transmissive display unit 10 in the TFT element substrate for the reflection-based semi-transmissive liquid crystal display device is 13%, and the ratio of the transmissive display unit 10 in the TFT element substrate for the transmission-based semi-transmissive liquid crystal display device is as follows. Small compared. However, a reflection-dominant transflective liquid crystal display device using the TFT element substrate, when performing transmissive display only when the display contents cannot be confirmed by the reflective display, is used as an illumination device (backlight) as background illumination means. ), The power consumption can be reduced by limiting the lighting time, so that sufficient practicality can be secured.

  Next, the structure of the color filter substrate used in combination with this TFT element substrate will be described below with reference to FIGS. 29 (a) and 29 (b).

  As shown in FIGS. 29 (a) and 29 (b), the color filter substrate for the reflection-based semi-transmissive liquid crystal display device is also used in the transmission-based semi-transmissive as shown in FIGS. 26 (a) and 26 (b). In the same manner as a color filter substrate for a liquid crystal display device, three color filters 61R, 61G, and 61B of red (R), green (G), and blue (B) are formed in a stripe pattern on a glass substrate 62. On the surface of the glass substrate 62 where the color filters 61R, 61G, and 61B are formed, a smoothing layer 501 is provided with a transparent acrylic resin so as to cover the color filters 61R, 61G, and 61B. As the counter electrode 502 of the element pixel electrode, ITO is formed by sputtering using a shielding mask that covers a region other than a predetermined region.

  However, the color filter substrate for the reflective main transflective liquid crystal display device shown in FIGS. 29 (a) and 29 (b) is a transmissive main transflective type shown in FIGS. 26 (a) and 26 (b). The color filter substrate for the liquid crystal display device is set so that the planar shape of the color filters 61R, 61G, and 61B and the spectral transmittance for each color are different.

  Specifically, in the color filter substrate for a reflection-based transflective liquid crystal display device, the color filters 61R, 61R, 61G, 61B (colored layers) are covered with the color filters 61R, 61G, 61B (colored layers). 61G and 61B are formed, and the color filters 61R, 61G, and 61B display light twice through the color filters 61R, 61G, and 61B in the reflective display unit 9 so that a good display can be obtained in the reflective display. In consideration of passing, the display light is produced with high lightness so that the light passes through the color filters 61R, 61G, and 61B twice and has good lightness.

  For this reason, in the reflective display part 9, favorable reflective display is implement | achieved by the combination of the TFT element board | substrate with a large ratio of the reflective display part 9 as mentioned above, and the color filter substrate matched with it as mentioned above.

  In the transmissive display unit 10, the ratio of the transmissive display opening 19 a is small, but the transmissive display used only when the ambient light is insufficient due to the combined use of the illumination device (backlight) as the background illumination means. The displayed contents can be confirmed. In this respect, the reflective main body transflective liquid crystal display device according to the present embodiment is different from the conventional reflective liquid crystal display device. In the reflective main transflective liquid crystal display device according to the present embodiment, when transmissive display is performed by the color filters 61R, 61G, and 61B adjusted for reflective display, the display color is insufficient. Can be confirmed.

  Therefore, when color display is performed by the reflection-based transflective liquid crystal display device, each pixel is provided with color filters 61R, 61G, and 61B in at least a reflective display unit, and color display is performed. The unit 10 does not use the color filters 61R, 61G, 61B, or has a saturation equal to or higher than that of the color filters 61R, 61G, 61B arranged in the reflective display unit 9 in at least a part of the transmissive display unit 10. It is particularly effective to arrange the color filters 61R, 61G, and 61B.

  As described above, in the reflection-based transflective liquid crystal display device, the color filters 61R, 61G, and 61B are formed at least in the reflective display portion, and the transmissive display portion 10 is an area (partial) where the color filters 61R, 61G, and 61B are not provided. ), And the transmissive display unit 10 may perform black and white display without using the color filters 61R, 61G, and 61B. In the latter case, since the light transmittance increases, the transmissive display unit 10 can be set smaller. Thereby, the area of the reflective display part 9 can be ensured more, and a more favorable display can be obtained in the reflective display at the time of normal use.

  In this case, similarly to the transmissive main transflective liquid crystal display device, in the reflective main transflective liquid crystal display device, the area of the display unit that does not perform color display, that is, in this case, the transmissive display unit 10 The area of the region where color display is not performed may be changed for each pixel of R, G, and B in accordance with the Y value of each color of R, G, and B of the color filters 61R, 61G, and 61B. In other words, in order to appropriately set the contribution to the brightness of the monochrome display of the transmissive display unit 10 in each of the R, G, and B pixels in consideration of the luminous transmittance, transmission is performed for each of the R, G, and B pixels. Each of the above substrates may be manufactured so that the ratio of the display area is different.

  On the other hand, although the power consumption when the illumination device (backlight) as the background illumination means is turned on increases, the illumination light of the illumination device (backlight) is made sufficiently strong so that the transmissive display unit 10 is adapted to the transmissive display. It is also possible to use a color filter with high saturation. In this case, not only saturation but also color reproducibility of transmissive display can be ensured. In any case, minimizing the lighting time of the lighting device (backlight) is important for reducing power consumption.

  As described above, according to the present embodiment, it is possible to reduce power consumption in normal use, without causing washout in the reflective display unit 9, and, if necessary, background illumination. A reflection-based transflective liquid crystal display device capable of performing transmissive display using means (backlight) can be realized.

  In the above description, the TFT element 21 is used as the switching element of the active matrix system, and the bottom gate type amorphous silicon TFT element is described as an example of the TFT element 21, but it is used in the present embodiment. The switching element to be used is not particularly limited to this, and may be, for example, a polysilicon TFT element or a MIM (Metal Insulator Metal) element that is a two-terminal element. Needless to say, these active elements are not necessarily used.

  In each liquid crystal display device according to the present embodiment, as described above, a TFT element substrate having a structure in which the drive electrode 19 that is a display electrode and the wirings 23 and 24 are separated by the organic insulating film 25 is used. Thus, the liquid crystal layer thickness can be changed between the reflective display portion 9 and the transmissive display portion 10 by the thickness of the organic insulating film 25. In addition, in these liquid crystal display devices, even if the film thickness of the organic insulating film 25 is set to a value of about 3 μm that enables high-capacity display in terms of wiring resistance and parasitic capacitance of the TFT element substrate, As shown in the first and second embodiments, it is possible to obtain a liquid crystal layer thickness difference that allows the reflective display unit 9 and the transmissive display unit 10 to both realize a satisfactory display.

  Therefore, a liquid crystal display device capable of high capacity display is realized by adopting the TFT element substrate having the structure shown in FIG. 23A or FIG. 28 and the liquid crystal display method described in the first or second embodiment. can do.

  Further, the TFT element substrate having the structure using the organic insulating film 25 as described above has already been partially put into practical use in a normal TFT element driving type liquid crystal display device only for transmissive display, and is technically also in mass production. There are few issues and practicality is high.

  In addition, the inventors of the present application have made studies on the production of a reflective film having good reflection characteristics by imparting smooth irregularities to the reflective film for the purpose of preventing the display surface from being mirrored in the reflective liquid crystal display device. Yes. As a result, it has been found that the same uneven surface can be produced also in the organic insulating film 25 used in the present invention, and the TFT for a transmission-dominant semi-transmissive liquid crystal display device shown in FIGS. In the element substrate, irregularities are formed in a portion corresponding to the reflective display portion 9.

  As described above, in the present embodiment, there are two types of usage modes of the liquid crystal display device, that is, a transmission-based semi-transmission type and a reflection-based semi-transmission type. It has been described that the ratio of the display area between the transmissive display portion and the reflective display portion and the color filter color design in the case of color display differ depending on whether the display is performed.

  In the following eighth embodiment, the ratio between the transmissive display unit and the reflective display unit in the liquid crystal display device according to the present invention will be described.

[Embodiment 8]
The ratio between the transmissive display unit and the reflective display unit needs to be set in consideration of visibility. The brightness perceived by the human eye considering the adaptation phenomenon of human vision (perceived lightness) is Stevens et al. (“Brightness Function: Effect of Adaptation”, Journal of the Optical Society of America, Vol. 53, No. 3). , p375). According to this document, even when the human eye is looking at the same brightness, the perceived brightness depends on the adapted brightness, and there is a quantitative relationship there. I understand.

FIG. 30 shows the relationship between the adaptation luminance and the sample luminance, which are produced by converting units from the literature such as Stevens et al. And give an equivalent perceptual lightness value of 5 to 45 bril. In FIG. 30, the horizontal axis indicates the adaptation luminance (unit: cd / m ² ) that the person who will observe the sample has adapted so far, and the vertical axis indicates the luminance of the sample presented to that person (unit: cd / m ² ). Sample luminance (unit: cd / m ² ) is shown.

In FIG. 30, a point A is a perceived lightness when a person who has adapted to an adaptation luminance of 1 cd / m ² observes a sample having a luminance surface of 10 cd / m ² , and a point B is an adaptation of 1700 cd / m ² . It represents the perceived lightness when a person who has adapted to luminance observes a sample having a luminance surface of 300 cd / m ² . From FIG. 30, since the perceived lightness is the same value (9.4 bril) at point A and point B, human perceptual lightness is influenced not only by the brightness of the display surface but also by the adaptation brightness. I understand that.

Next, consideration will be given to the adaptation of the observer on the display surface of the liquid crystal display device.
First, consider the object to which the observer adapts. When a person observes an object and adjusts to the brightness of the object, the object to be adjusted is the brightness of the surface of the object to be viewed around the visual environment, and the surface of the object to be viewed The brightness of is generally dependent on various environmental conditions. However, as an index, it is useful to consider the adaptation target, that is, to consider this case, assuming that the surface of the observation target is a reflective surface that reflects ambient light. The reason for this is that the situation where a person sees and adapts to the light source itself, whether indoors or outdoors, is more suitable than the situation where the person adapts to the reflective surface of the object illuminated by the light source. This is because it is natural to think that there are few. In the following, consideration will be given to the adaptation of an observer who is adapting his / her vision to the reflecting surface of the observation object.

When the luminance surface of the observation object is a reflection surface, the adaptation luminance shown in FIG. 30 is obtained by multiplying the illuminance on the object surface by a certain value by the illumination light source that illuminates the object surface to which the observer adapts. Indicated by value. Assuming that the illuminance is L (unit: lux) and the luminance is B (unit: cd / m ² ), the luminance (B) of the surface having a reflectance of R for the perfect diffuse reflection surface is B = L × R / π. Here, the reflectance of the surface of the Munsell color chart N5, which is said to have an average reflectance of a normal human observation object, is used, and the surface of the Munsell color chart N5 illuminated by a certain illuminance is used. It is appropriate to consider the luminance as the adaptation luminance. In this case, R is 0.2.

  Furthermore, the illumination light source that illuminates the surface of the Munsell color chart N5, which is the representative of the observation object, is evaluated not only on the adaptation object, that is, the surface of the Munsell color chart N5, but also on the perceptual lightness under the adaptation conditions. Assume that the target sample surface is illuminated at the same time. Based on this assumption, the perceived brightness of the reflective display unit when observing the liquid crystal display device is combined with the illuminance that illuminates the liquid crystal display device through the adaptive luminance. Thereby, based on the data of a psychophysical experiment, the specific selection of a reflectance and the ratio of the area of a reflective display part is attained.

  According to the study by the inventors of the present application, a specific standard of perceived lightness can be paraphrased as lightness as shown in Table 9. This actually reproduces some combinations of adaptation luminance and sample luminance, and concludes that such lightness expression is appropriate, and it is a measure for setting the reflective display unit based on perceived lightness. .

  Here, since the typical reflectance (R) of the reflective liquid crystal display device is about 30% in the polarizing plate system, the operation of the transflective liquid crystal display device according to the present invention is performed using this numerical value. Will be described.

  A straight line 601 illustrated in FIG. 30 indicates a display operation of the liquid crystal display device having a reflectance of 30%. That is, when the illuminance of the illumination light source that illuminates the luminance surface to which the observer adapts is L (unit: lux), the adaptation luminance by the surface of the Munsell color chart N5 is the reflectance (R) of the surface of the Munsell color chart N5. = 20%) is related to the luminance (L / π) of the completely diffuse reflecting surface illuminated by the same illumination, and is 0.2 × L / π. Similarly, the sample brightness of the display surface of a liquid crystal display device (target sample) having a reflectance of 30% illuminated by the same illumination is 0.3 × L / π. That is, the straight line 601 is a straight line obtained by plotting points satisfying the relationship of 0.2 L / π on the horizontal axis and 0.3 L / π on the vertical axis while varying the illuminance (L). Similarly to the case where the above liquid crystal display device having a reflectance of 30% is used as the target sample, the liquid crystal display device having a reflectance of 10% is used as the target sample, and the horizontal axis is 0.2 L / π and the vertical axis is 0. A straight line obtained by plotting points satisfying the relationship of .1L / π is a straight line 602.

Next, the usable environment of the liquid crystal display device having a reflectance of 30% will be considered below. In the illuminance (approximately 100,000 lux) of direct-light light in fine weather, which is the brightest lighting condition that a person experiences in daily life, the adaptation luminance by the surface of the Munsell color chart N5 is approximately 6000 cd / m ² . At this time, the perceived brightness of the display surface of the liquid crystal display device having a reflectance of 30% is approximately the perceived brightness at the intersection of the straight line 605 and the straight line 601 indicating the adaptation luminance 6000 cd / m ^2, as shown in FIG. As shown in Table 9, it is a value that feels dazzling. In addition, the perceived brightness under darker illumination is lower than the above perceived brightness, and the illuminance that can ensure the perceived brightness of 10 brill is obtained by calculating back the above-described formula using the corresponding adaptive brightness value. About 450 lux. In other words, if a bright display of 10 to 30 brilliant is required, the minimum illuminance is 450 lux and the maximum illuminance is 100,000 lux. Can be used in a room (for example, a room with illumination of 450 lux or more), but in a darker place, the illuminance is not sufficient and it becomes difficult to perceive.

  Further, the relationship between the adaptation luminance and the sample luminance when the reflectance is 50% is indicated by a straight line 603 (FIG. 30). As can be seen from the straight line 603, when a reflective display is realized with a reflectance of 50% or more like ordinary white paper, high illuminance of 1800 lux or more (for example, indoors in a bright window, direct sunlight, etc.) Under the environment, the perceived lightness exceeds 30 brilli. This indicates that white paper feels dazzling in such an environment. Therefore, it is inappropriate to use a display surface having a reflectivity of 50% or more in a high illumination environment in view of visibility. When reflective display is performed in such an environment, the display surface ( It can be seen that the reflectance of the (luminance surface) is preferably about 30%.

  On the other hand, the illuminance that gives a perceived lightness of 10 brills in the reflective display at a reflectance of 30% and the reflective display at a reflectance of 10% shown by straight lines 601 and 602 is about 450 lux and 3000 lux, respectively. That is, when the reflectance becomes 1/3, it is necessary to provide illumination that is 6.7 times brighter. This means that if the illumination is increased because the reflectance of the liquid crystal display device has dropped, the human eye must adapt to a bright reflector other than the liquid crystal display device, and the illumination must be stronger than the reciprocal of the reflectance change ratio. Is shown to occur.

  Further, as can be seen from FIG. 30, the display on a display body having a certain luminance (for example, a general light-emitting display device) has a problem that it feels very dark particularly when the surroundings are bright. .

  However, in the transflective liquid crystal display device according to the present invention, a constant luminance determined by the background illumination light and the transmittance in the transmissive display portion and a luminance (sample) determined by the constant reflectance in the reflective display portion. (Luminance) is used for display. That is, in the transflective liquid crystal display device according to the present invention, for example, display with the display luminance indicated by the curve 604 shown in FIG. 30 is realized. As shown by the curve 604, in the transflective liquid crystal display device according to the present invention, when the illumination illuminance is high, the visibility is ensured by reflection display, and when the illumination illuminance is low, the background illumination is obtained. Visibility can be ensured by transmissive display using a lighting device (backlight) as a means.

Further, FIG. 31 shows the result of obtaining the perceived lightness by changing the illuminance using the display luminance of the transflective liquid crystal display device. For comparison, FIG. 31 also shows the relationship between the illuminance and the perceived lightness in the transmissive liquid crystal display device and the relationship between the illuminance and the perceived lightness in the reflective liquid crystal display device. Here, the calculation of the perceptual lightness is 30% in the case where the entire display area is in the reflective color display, 7.5% in the case where the entire display area is in the transmissive color display, and the backlight luminance is 2000 cd / m ² , the illuminance on the surface to which the observer is adapting is equal to the illuminance on the display surface of the liquid crystal display device, and the reflectance of the adaptation target surface is 20% assuming the brightness of the Munsell color chart N5 .

In FIG. 31, the value of the perceived lightness when the illuminance is changed differs depending on the ratio (Sr) of the reflective display portion of the displayable area in the transflective liquid crystal display device. A curve 611 shows the relationship between illuminance and perceived lightness in a normal transmissive liquid crystal display device in which Sr = 0, that is, only transmissive display and no reflective display is performed. The luminance of the display surface in the transmissive liquid crystal display device is 150 cd / m ² , and when the illuminance is about 6000 lux or more, the perceived lightness is 10 brills or less. Therefore, in order to secure a perceptual lightness of 10 brill or more by changing a part of the transmissive display part to the reflective display part, as shown by the curve 612, Sr = 0.1, that is, 1 of the displayable area. The area of / 10 needs to be a reflective display portion.

  A curve 613 is a curve showing the relationship between illuminance and perceived brightness in a reflective liquid crystal display device that performs only reflective display, that is, Sr = 1. The reflectance of the display surface of the reflective liquid crystal display device is 30% as compared with a completely diffusive reflective surface. When the illuminance is about 450 lux or less, the perceived lightness is 10 bril or less. Therefore, in order to secure a perceptual lightness of 10 brill or more by changing a part of the reflective display part to the transmissive display part, as shown by the curve 614, Sr = 0.9, that is, 1 of the displayable area. It is necessary to provide a transmissive display portion having an area of / 10.

  Further, according to FIG. 31, it can be seen that an excellent display with a perceived lightness of 10 brill or more and less than 30 brill can be performed at an Sr value of 0.1 to 0.9, and the Sr is 0.30 (curve 615). Alternatively, when it is set to 0.50 (curve 616), it can be seen that a bright and good display with a perceived lightness of 20 brill or more and less than 30 brill can be performed.

  Further, surface reflection occurs on the surface of the liquid crystal display device. The effect of the display obstruction due to the surface reflection becomes more remarkable as the ambient illuminance increases. FIG. 31 also shows the relationship between perceived lightness and illuminance due to this surface reflection (curve 617). The surface reflection is greatly influenced by the surface treatment, but in the curve 617, the surface reflection generated at the interface between the medium having a refractive index of 1.5 and air has the same diffusivity as the completely diffusing surface ( That is, the relationship between the perceived lightness of the surface and the illuminance when the reflectance by surface reflection is 4% is shown. Therefore, in consideration of surface reflection, the area of the reflective display unit is more preferably 30% or more of the sum of the area of the reflective display unit and the area of the transmissive display unit (that is, Sr ≧ 0.3). It is preferable to perform a correct display.

  According to the above analysis, according to the present embodiment, when both the reflective display unit and the transmissive display unit perform color display, the reflective display unit in the sum of the area of the reflective display unit and the area of the transmissive display unit. It can be seen that good display can be performed when the area ratio is 30% or more and 90% or less.

  In addition, even when color display is not used for at least one of the reflective display and the transmissive display, the ratio of the area of each display unit for performing good display can be analyzed by the same method as described above. In any case, a good display can be realized when the ratio of the area of the reflective display unit in the sum of the area of the reflective display unit and the area of the transmissive display unit is within the above-described range. it can. Note that, in both the transmission-based semi-transmissive liquid crystal display device and the reflection-based semi-transmissive liquid crystal display device described in the seventh embodiment, the reflective display unit in the sum of the area of the reflective display unit and the area of the transmissive display unit. The area ratio is prepared at the above-mentioned preferable ratio.

[Embodiment 9]
In the present embodiment, an active matrix type liquid crystal display device using the liquid crystal display method described in the first and second embodiments, more specifically, a color display is realized by using a TFT element substrate. The liquid crystal display device will be described with specific examples, but the liquid crystal display device according to the present embodiment is not limited to the following examples.

  The manufacturing process of the active matrix liquid crystal display device according to this embodiment includes a process for manufacturing a TFT element substrate, a process for manufacturing a color filter substrate, and liquid crystal injection using these TFT element substrate and color filter substrate. A liquid crystal cell for liquid crystal display, and a step of assembling a liquid crystal display device by injecting liquid crystal into the obtained liquid crystal cell for liquid crystal injection.

  First, a manufacturing method of an active matrix type liquid crystal display device according to each of the following examples in this embodiment will be described in order from the manufacturing process of the TFT element substrate.

  As shown in FIGS. 23A to 25, the TFT element substrate has a configuration in which a TFT element 21 is formed for each pixel on a translucent substrate 29 by the following process. Yes.

  As the substrate 29 on which the TFT element 21 is formed, a glass substrate made of alkali-free glass or the like not containing an alkali component was used. First, on the substrate 29, a wiring 23 as a gate wiring and a tantalum serving as the auxiliary capacitance line 27 were formed by sputtering and further patterned to form the wiring 23 and the auxiliary capacitance line 27. At this time, the wiring 23 and the auxiliary capacitance line 27 are patterned so that the level difference between the respective wirings (the wiring 23 and the auxiliary capacitance line 27) becomes gentle, and a wiring 24 described later is formed on these wirings. Wire breakage is prevented by improving the coverage.

Further, a tantalum oxide (Ta ₂ O ₅ ) layer was formed on the wiring 23 and the auxiliary capacitance line 27 by an anodic oxidation process, and silicon nitride serving as a gate insulating film was formed thereon. Further, a hydrogenated amorphous silicon layer serving as an intrinsic semiconductor layer (i layer) serving as a switching region of the TFT element 21 and a silicon nitride layer serving as an etching stopper layer are sequentially formed thereon in a chemical vapor phase using monosilane gas. It was formed by a growth (CVD) method and sputtering (silicon nitride). Next, after patterning the silicon nitride layer as the uppermost etching stopper layer, an n ⁺ layer to be the source terminal 28 and the drain terminal 22 of the TFT element 21 was formed by CVD using monosilane gas mixed with phosphine gas. . Next, the n ⁺ layer and i layer were patterned, and the gate insulating film was further patterned. At this time, silicon nitride in the connection terminal portion outside the display region in the wiring 23 (gate wiring) was also removed.

  Next, ITO to be the transparent pixel electrode 20 was formed by sputtering so as to be in contact with the source terminal 28 and the drain terminal 22, and further, tantalum to be the wiring 24 as the source wiring was formed by sputtering. The tantalum was patterned to form the wiring 24, and the ITO film formed under the tantalum was patterned to form the transparent pixel electrode 20. The transparent pixel electrode 20 is in contact with the source terminal 28 and the drain terminal 22 as described above, and also plays a role of forming an ohmic contact between these terminals (source terminal 28 and drain terminal 22) and the wirings 23 and 24. .

  Next, an organic insulating film 25 having a concavo-convex structure is formed on the surface of the TFT element 21 as an insulating film for a reflective display portion. Aluminum that becomes the drive electrode 19 of the reflective display unit 9 is formed by sputtering so as to be in contact with the pixel electrode 20, and the obtained aluminum film is patterned by dry etching, so that the surface of the organic insulating film 25 has the same uneven structure. The drive electrode 19 having a concavo-convex structure as a reflective electrode was formed.

  In each of the above patterning steps, each component is formed into a necessary shape based on the design by a photolithography technique. In these photolithography processes, a photosensitive resin film (resist) coating / drying process, a pattern exposure process, a development process, a resist baking and curing process, a dry etching process, a wet etching process, and a resist peeling and removing process were used in combination.

  Moreover, the uneven structure formed in the reflective display part 9 apply | coated the insulating photopolymerizable resin material, and produced it using the pattern exposure process, the image development process, and the hardening process process. That is, a dot-like pattern was formed in the development process, and a smoothing layer was further formed of the same material on the dot pattern. The organic insulating layer 25 is not formed on the transmissive display unit 10.

  In the TFT element substrate manufactured by the above-described process, the TFT element 21 is arranged for each pixel, and each pixel includes a reflective display portion 9 and a transmissive display portion 10. Here, two types of TFT element substrates, that is, the TFT element substrate shown in FIG. 23A and the TFT element substrate shown in FIG. 28, are produced, and the ratio between the transmissive display unit 10 and the reflective display unit 9 is In the seventh embodiment, the ratio is as described in the description of each liquid crystal display device.

  Next, a manufacturing process of the color filter substrate will be described. The color filter substrate manufacturing step includes a step of manufacturing a colored layer (color filter) of R, G, and B on the substrate, a step of manufacturing a flattening layer on the color filter, and the TFT on the flattening layer. The process includes a step of forming a counter electrode facing the transparent pixel electrode 20 on the TFT element substrate side driven by the element 21.

  In the present embodiment, as shown in FIG. 26B or FIG. 29B, the color filter substrate has three red (R), green (G), and blue (B) on the glass substrate 62. Color filters 61R, 61G, and 61B are formed in stripes, and a smoothing layer 501 is formed on the glass substrate 62 on the color filter 61R, 61G, and 61B forming surface so as to cover the color filters 61R, 61G, and 61B. It was formed by forming a counter electrode 502 thereon.

  In forming the color filter substrate, the color filters 61R, 61G, and 61B were formed by patterning a resin material in which a pigment is dispersed in a photosensitive resin by a photolithography method. In addition, as a manufacturing method of the color filter 61R / 61G / 61B, a method other than the above-described method using pigment dispersion, for example, an electrodeposition method, a film transfer method, a dyeing method, or the like can be adopted, and the method is particularly limited. It is not done.

  The planarizing layer 501 was formed by applying an acrylate resin having a high light transmittance on the surface of the glass substrate 62 where the color filters 61R, 61G, and 61B were formed, and curing the resin with heat. Further, the counter electrode 502 formed on the planarizing layer 501 is a counter electrode facing the pixel electrode 18 driven by the TFT element 21, and ITO is deposited as a transparent electrode through a mask by sputtering to form a necessary plane. It was formed by taking a shape.

  In the present embodiment, two types of color filter substrates are produced: a color filter substrate whose chroma is set high in accordance with transmissive display and a color filter substrate whose brightness is set high in accordance with reflective display. Then, the color filter substrate set with high saturation is manufactured in the pattern shown in FIGS. 26A and 26B, and the color filter substrate set with high brightness is shown in FIGS. The pattern shown in b) was produced.

  Next, in order to produce a liquid crystal display device using the TFT element substrate and the color filter substrate produced as described above, the TFT element substrate and the color filter substrate are arranged to face each other and liquid crystal for liquid crystal injection is used. A process for manufacturing a cell will be described.

  In this step, first, in the liquid crystal display region on the mutually opposing surfaces of the TFT element substrate and the color filter substrate (the TFT element 21 formation surface on the TFT element substrate and the color filter 61R / 61G / 61B formation surface on the color filter substrate). Then, a soluble polyimide solution was disposed by an offset printing method, and an alignment film was formed through drying and baking processes. Further, an alignment treatment for determining the liquid crystal alignment direction was performed on the alignment film by a rubbing method. Whether the alignment film is parallel or vertical is different depending on each example described later.

  Subsequently, spherical spacers having a uniform particle diameter are dispersed on one of the TFT element substrate and the color filter substrate thus treated, and on the other side, a liquid crystal layer is sealed and the TFT element substrate and the color filter substrate are fixed. A conductive paste for conducting the counter electrode 502 was disposed from the TFT element substrate side to the color filter substrate side.

  Then, the TFT element 21 formation surface of the TFT element substrate and the color filter 61R / 61G / 61B formation surface of the color filter substrate are arranged to face each other, and the two substrates (TFT element substrate and color filter substrate) are aligned and added. The encapsulating sealant and conductive paste were cured under pressure.

  Through the above steps, a mother glass substrate 21 in which a plurality of liquid crystal cells for liquid crystal injection were arranged was manufactured, and the mother glass substrate was further divided to prepare a liquid crystal injection cell.

  Thereafter, a liquid crystal composition is introduced into the liquid crystal cell not filled with liquid crystal by a vacuum injection method, and a photopolymerizable resin is applied to the liquid crystal introduction port so that the introduced liquid crystal layer does not come into contact with the outside air. A liquid crystal cell was prepared by polymerization and curing.

  Next, for the purpose of preventing electrostatic breakdown of the TFT element 21, the short ring portion arranged at the end of the TFT element substrate was removed so as to short-circuit each wiring terminal, and an external circuit for driving the TFT element 21 was connected. . Further, an active matrix liquid crystal display device according to this embodiment was manufactured by disposing a backlight as a light source for transmissive display.

Example 14
The active matrix type liquid crystal display device according to this example is a transmissive-based semi-transmissive type liquid crystal display device using the GH method, and the GH method in Example 1 of the first embodiment is used for display. It is a liquid crystal display device.

  The liquid crystal composition used in this example is prepared in accordance with Example 1 of the first embodiment. That is, in this example, a liquid crystal composition using the dichroic dye described in Example 1 (dichroic dye 12) was used. In this example, a vertical alignment film having vertical alignment properties was used as the alignment film, and an alignment treatment by rubbing was performed so as to obtain a uniform vertical alignment. In this embodiment, since the GH method using a dichroic dye is adopted for the liquid crystal composition, the retardation compensation plate and the polarizing plate are not attached to the liquid crystal cell.

  In this embodiment, since transmissive display is mainly used, the color filters 61R, 61G, and 61B are designed to have high saturation as in the case of the conventional transmissive display type color filter, and the color filter substrate is shown in FIG. Arranged as shown in a) and FIG. As the TFT element substrate to be combined with this color filter substrate, as shown in FIG. 23A, a TFT element substrate having a large transmissive display opening 19a and a wide transmissive display portion 10 was used.

  In the liquid crystal display device according to the present embodiment, as shown in FIG. 26A and FIG. 26B, the drive electrode 19 in the reflective display unit 9 is a part thereof (the color filter 61R in the drive electrode 19). (Only the portions facing the color filters 61R, 61G, and 61B in the extending direction of 61G and 61B) are covered with the same color filters 61R, 61G, and 61B as the transmissive display opening 19a forming region that becomes the transmissive display unit 10. It also has a display portion that does not have a color filter and allows white light to pass therethrough.

  A display signal was input to the liquid crystal display device thus manufactured, and visual observation was performed. As a result, in this embodiment, it was necessary to always turn on the backlight. However, when the backlight is turned on, both the brightness and the contrast ratio are good, and sufficient display is always possible. In addition, the display contents were visible even under direct sunlight, and no washout occurred.

  That is, in this embodiment, a liquid crystal display device with high brightness is realized by a backlight as in a conventional transmissive liquid crystal display device in an environment with low ambient light. On the other hand, when ambient light is strong, the reflective display unit 9 is Since the brightness changes in proportion to the ambient light, it is possible to check the display content, and no high-resolution color liquid crystal display device with no parallax without the washout that occurs in conventional light-emitting display devices and transmissive liquid crystal display devices. Can be realized. In this example, a very good reflective display without parallax (double image) was realized.

Example 15
The active matrix type liquid crystal display device according to this example is a reflection-based transflective type liquid crystal display device using the GH method, and the GH method in Example 1 of the first embodiment is used for display. It is a liquid crystal display device.

  Also in this example, as in Example 14, the liquid crystal composition is prepared in accordance with Example 1 of the first embodiment. That is, also in this example, the liquid crystal composition using the dichroic dye (dichroic dye 12) described in Example 1 was used. In this example, a vertical alignment film having vertical alignment properties was used as the alignment film, and an alignment treatment by rubbing was performed so as to obtain a uniform vertical alignment. In this embodiment, since the GH method using a dichroic dye is adopted for the liquid crystal composition, the retardation compensation plate and the polarizing plate are not attached to the liquid crystal cell.

  In this embodiment, since reflective display is mainly used, the color filters 61R, 61G, and 61B are manufactured so as to have higher brightness than the color filters used in the conventional transmissive liquid crystal display device. The filter substrate was arranged as shown in FIGS. 29 (a) and 29 (b). As the TFT element substrate to be combined with the color filter substrate, as shown in FIG. 28, a TFT element substrate having a small transmissive display opening 19a and a large reflective display portion 9 was used.

  A display signal was input to the liquid crystal display device thus manufactured, and visual observation was performed. As a result, the above-described liquid crystal display device according to the present example did not require the backlight to be turned on under daylight illumination / external light environment, and was capable of reflective display. In this example, a very good reflective display without parallax (double image) was realized. Further, when the ambient light is so dark that observation with reflected light is impossible, the display contents can be visually confirmed by turning on the backlight.

  That is, in the present embodiment, as described above, since the color filters 61R, 61G, 61B and the color filter substrate adapted to the reflective display are used, color display using only the reflected light is possible. For this reason, it is possible to use only by reflective display with the backlight turned off in normal indoor lighting or outdoors during the daytime. Further, by turning on the backlight as necessary, visibility can be ensured even when the illumination is dark.

  In the liquid crystal display device according to the present embodiment, it is not necessary to always turn on the backlight as in the case of the conventional transmissive liquid crystal display device, power consumption can be reduced, and the reflective display unit 9 can be used for washing. There is no out-out, and transmissive display using a backlight can be performed as necessary.

Example 16
The active matrix type liquid crystal display device according to this example is a transmissive main body semi-transmissive type liquid crystal display device using the polarization conversion action of the liquid crystal layer for display, and the polarizing plate in Example 5 of the second embodiment. This is a liquid crystal display device using the method for display.

  The liquid crystal composition used in this example is prepared according to Example 5 of the second embodiment. In this example, a phase difference compensating plate (phase difference compensating plates 16 and 17) and a polarizing plate (polarizing plates 14 and 15) were attached to a liquid crystal cell (TFT liquid crystal panel) into which liquid crystal was injected. Further, in this example, the alignment treatment was performed on the parallel alignment film by a rubbing method so that the rubbing crossing angle was 250 degrees.

  Further, in this embodiment, the transmissive display is mainly used as in the case of the embodiment 14. Therefore, the color filters 61R, 61G, and 61B are designed to have a transmissive color similar to that of the conventional transmissive display type color filter, and the color filter substrate Were arranged as shown in FIGS. 26 (a) and 26 (b). As the TFT element substrate to be combined with this color filter substrate, as shown in FIG. 23A, a TFT element substrate having a large transmissive display opening 19a and a wide transmissive display portion 10 was used.

  In the liquid crystal display device according to the present embodiment, as shown in FIGS. 26A and 26B, the drive electrode 19 of the reflective display section 9 is a part thereof (the color filter 61R in the drive electrode 19). (Only the portions facing the color filters 61R, 61G, and 61B in the extending direction of 61G and 61B) are covered with the same color filters 61R, 61G, and 61B as the transmissive display opening 19a forming region that becomes the transmissive display unit 10. It has no color filter and also has a display portion that reflects white light.

  A display signal was input to the liquid crystal display device thus manufactured, and visual observation was performed. As a result, in this embodiment, it was necessary to always turn on the backlight. However, when the backlight is turned on, both the brightness and the contrast ratio are good, and sufficient display is always possible. In addition, the display contents were visible even under direct sunlight, and no washout occurred.

  That is, in this embodiment, a liquid crystal display device with high brightness is realized by a backlight as in a conventional transmissive liquid crystal display device in an environment with low ambient light. On the other hand, when ambient light is strong, the reflective display unit 9 is Since the brightness is changed in proportion to the ambient light, the display content can be confirmed, and it can be seen that the washout that occurs in the conventional light-emitting display device and transmissive liquid crystal display device does not occur. In this example, a very good reflective display without parallax (double image) was realized.

Example 17
The active matrix type liquid crystal display device according to this example is a reflection-based transflective type liquid crystal display device that uses the polarization conversion action of the liquid crystal layer for display, and the polarizing plate in Example 5 of the second embodiment. This is a liquid crystal display device using the method for display.

  Also in this example, the liquid crystal composition was prepared in accordance with Example 5 of the second embodiment, as in Example 16. Also in this example, a phase difference compensation plate (phase difference compensation plates 16 and 17; see Example 5) and a polarizing plate (polarizing plates 14 and 15) are provided in a liquid crystal cell (TFT liquid crystal panel) into which liquid crystal is injected. Affixed. In this example, the alignment treatment was performed on the parallel alignment film by a rubbing method so that the rubbing crossing angle was 250 degrees.

  In the present embodiment, as in the fifteenth embodiment, since the reflective display is mainly used, the color filters 61R, 61G, and 61B have higher brightness than the color filters used in the conventional transmissive liquid crystal display device. The color filter substrate was prepared as shown in FIGS. 29 (a) and 29 (b). As the TFT element substrate to be combined with the color filter substrate, as shown in FIG. 28, a TFT element substrate having a small transmissive display opening 19a and a large reflective display portion 9 was used.

  A display signal was input to the liquid crystal display device thus manufactured, and visual observation was performed. As a result, the above-described liquid crystal display device according to the present example did not require the backlight to be turned on under daylight illumination / external light environment, and was capable of reflective display. In this example, a very good reflective display without parallax (double image) was realized. Further, when the ambient light is so dark that observation with reflected light is impossible, the display contents can be visually confirmed by turning on the backlight.

  That is, in the present embodiment, as described above, since the color filters 61R, 61G, 61B and the color filter substrate adapted to the reflective display are used, color display using only the reflected light is possible. For this reason, it is possible to use only by reflective display with the backlight turned off in normal indoor lighting or outdoors during the daytime. Further, by turning on the backlight as necessary, visibility can be ensured even when the illumination is dark.

  In the liquid crystal display device according to the present embodiment, it is not necessary to always turn on the backlight as in the case of the conventional transmissive liquid crystal display device, power consumption can be reduced, and the reflective display unit 9 can be used for washing. There is no out-out, and transmissive display using a backlight can be performed as necessary.

  As described above, according to Embodiments 14 to 17, according to the present embodiment, a high-resolution active matrix liquid crystal display device that realizes the liquid crystal display method described in Embodiments 1 and 2 is realized. It was shown that you can.

  In Examples 14 to 17, the active matrix substrate (TFT element substrate) and the organic insulating film 25 (corresponding to the insulating film 11) have different liquid crystal display thicknesses in the reflective display section 9 and the transmissive display section 10. Although the device was manufactured, it is needless to say that the same effect can be expected by other liquid crystal display principles according to the present invention.

[Embodiment 10]
In the present embodiment, a change in luminance of a backlight used in the liquid crystal display device according to the present invention will be described below.

There are mainly three purposes for changing the luminance of the backlight.
The first purpose is to ensure visibility. As shown in the eighth embodiment, the perceived lightness of a person is defined by the adaptation luminance and the luminance of the display surface. Therefore, in order to realize a display with good visibility, it is effective to change the luminance of the backlight according to the perceived brightness of the human eye according to the adaptation luminance, as shown in the eighth embodiment. In addition, it is desirable to change the luminance of the display surface by controlling the luminance of the backlight in accordance with the adaptation luminance so that the perceived lightness is not less than 10 bris and less than 30 bris. That is, the backlight also serves as display surface luminance changing means. Thereby, the visibility in the situation where the transmissive display mainly contributes to the display can be improved. Here, the value of the perceived lightness defined in the eighth embodiment assumes the brightness of the display surface in proportion to the adapting brightness with which the person is adapting. A good display can be obtained by changing.

  The second purpose is to reduce power consumption. There are cases where the visibility is not greatly affected even if the backlight is turned on or off. For example, when the liquid crystal display device is a transflective liquid crystal display device, the illuminance of illumination light that illuminates the liquid crystal display device from the surroundings is sufficiently high, and the luminance of the display surface is mainly maintained by the reflective display unit It is. In such a case, even if the luminance in transmissive display is high, the luminance of the display surface may not be affected. In such a case, it is desirable to turn off the backlight in order to reduce power consumption.

  The third purpose is to intentionally use a state in which color display and black-and-white display can be switched by turning on the backlight when color display is performed on only one of the reflection display and the transmission display. In other words, one liquid crystal display device has a plurality of functions.

  For example, when a color display is performed without providing a color filter in the reflective display unit, and a color display is performed with a color filter disposed only in the transmissive display unit, the resolution of the reflective display is set to a plurality of pixels using the color filter. Therefore, the reflective display performs high-resolution black-and-white display, and the transmissive display can display colors although the resolution is not high. Conversely, the color filter can be used only in the reflective display. In this case, a single liquid crystal display device can have functions for different purposes. Therefore, by switching between color display and black-and-white display by turning on the backlight, or changing the emission color, the display contents can be changed greatly depending on the lighting state.

  As described above, the luminance of the backlight can be controlled by an appropriate signal each time in accordance with the purpose of use and the situation of use. When changing the luminance of the backlight according to the adaptation luminance described above, the luminance of the backlight is for the purpose of improving visibility, for example, the illumination intensity incident on the display surface, the type of display of the liquid crystal display device, etc. It is possible to control according to the visual environment.

  When the brightness of the backlight is controlled by illuminance, when the illuminance is high, the backlight is turned off, and when the illuminance is low, the backlight is turned on weakly to avoid glare and the illuminance is in the middle It is desirable to control the lighting state of the backlight, such as turning on the backlight strongly.

  In this case, depending on the state of the user and the like, if the backlight is turned on and the brightness is controlled by signals from various external devices connected to the liquid crystal cell or the liquid crystal display device, timer control, etc., Unnecessary power consumption can be reduced.

  Furthermore, when controlling the brightness of the backlight, for example, when the user performs some operation on the device equipped with the liquid crystal display device, or when the backlight is turned on only for a certain period, the device It is possible to achieve both reduction of the overall power consumption and provision of a good display to the user. Note that the luminance of the backlight may be controlled by various other signals in addition to the illuminance of the illumination incident on the display surface as described above.

  In addition, the presence / absence of brightness of the backlight, the luminance, or the liquid crystal orientation in the reflective display portion or the transmissive display portion, depending on the signal input by the user to the touch panel (pressed coordinate detection type input means) placed on the display surface of the liquid crystal cell Controlling the brightness of the backlight in conjunction with a signal that urges other users to take some attention is also very effective in achieving the above-described object. Thus, by controlling the luminance of the display surface from the outside of the liquid crystal cell, a liquid crystal display device capable of achieving both visibility and low power consumption can be obtained.

[Embodiment 11]
In this embodiment, a specific example of the liquid crystal display device according to the present invention when a touch panel (pressed coordinate detection type input means) is used as information input means in a portable device, which is a main field of application of the liquid crystal display device of the present invention. A typical configuration will be described. For convenience of explanation, components having the same functions as those in the first to tenth embodiments are denoted by the same reference numerals and description thereof is omitted.

  In this embodiment mode, a touch panel is overlapped with the liquid crystal display device according to Embodiment 17 in Embodiment 9, so that a transflective liquid crystal display device integrated with an input device is manufactured. FIG. 32 shows the configuration of the liquid crystal display device integrated with an input device according to this embodiment. In addition, in the liquid crystal display device according to the present embodiment, the basic configuration other than the touch panel 71, that is, the configuration of the liquid crystal cell and the backlight 13 is the same as that of the embodiment 17 and the embodiment 2 of the embodiment 9. Since it is the same as that of Example 5, it abbreviate | omits here.

  The touch panel 71 includes a movable substrate 73 provided with a transparent electrode layer 72 and a support substrate 75 provided with a transparent electrode layer 74. The movable substrate 73 and the support substrate 75 are arranged such that the transparent electrode layer 72 and the transparent electrode layer 74 are opposed to each other, and a predetermined gap is provided by a spacer (not shown) so that the transparent electrode layers do not contact each other in the energized state. And are arranged opposite to each other. Thus, the transparent electrode layer 72 provided on the movable substrate 73 and the transparent electrode layer 74 provided on the support substrate 75 do not contact each other in a normal state, but the movable substrate 73 is instructed with a finger or a pen. By being (pressed), they come into contact with each other at the designated location. For this reason, the touch panel 71 functions as an input device by detecting a contact position (coordinate position) between the transparent electrode layer 72 and the transparent electrode layer 74 due to a pressing force applied to the movable substrate 73.

  The touch panel 71 has the retardation compensation plate 16 and the polarizing plate 14 affixed on the movable substrate 73 so that the retardation compensation plate 16 is interposed between the retardation compensation plate 16 and the substrate 4 of the liquid crystal cell. And the polarizing plate 14 are integrally disposed. In the present embodiment, in order to obtain the effect of the polarizing plate in Example 17 with the polarizing plate 14 affixed on the touch panel 71, the movable substrate 73 and the support substrate 75 constituting the touch panel 71 are birefringent. It is made of a material that does not have any.

  Further, in the present embodiment, the above-described liquid crystal display device is combined with the support substrate 75 of the touch panel 71 so that the liquid crystal display device has an effect of preventing the pressure force transmission between the touch panel 71 and the substrate 4 of the liquid crystal cell. By providing a gap between the substrate 4 of the liquid crystal cell and keeping this gap constant, the pressing force applied to the touch panel 71 is not transmitted to the liquid crystal cell without using a pressing force buffer member.

  The liquid crystal display device integrated with the input device configured as described above turns off the backlight 13 when the user is not observing the display by changing the luminance of the backlight 13 according to the signal of the touch panel 71. The backlight 13 can be turned on as information is input to the touch panel 71. Therefore, according to the present embodiment, it is possible to realize a liquid crystal display device that achieves both good display and reduced power consumption. Moreover, according to this Embodiment, by arrange | positioning the said polarizing plate 14, the touch panel 71, and a liquid crystal cell in the order mentioned above, absorption by the polarizing plate 14 also absorbs unnecessary reflected light by the touch panel 71, and this unnecessary. Since reflected light can be reduced, visibility can be improved.

  As described above, the first liquid crystal display device includes a pair of substrates having alignment means (for example, an alignment film) on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates. A liquid crystal display device comprising: an alignment mechanism (for example, used for display in the liquid crystal layer) that allows at least two different alignment states to be taken simultaneously in any and different regions used for display in the liquid crystal layer. At least two types of electrodes are provided in any and different regions that are used for display in the liquid crystal layer, electrodes that apply different voltages to different regions or generate different electric fields, applied voltages, or liquid crystal layers. Alignment films that are aligned in different orientations, or at least two different thicknesses in the liquid crystal layer used for display. An edge film, a substrate, a specific liquid crystal material, a liquid crystal layer structure formed so as to be driven independently, a polarizing plate, a retardation compensator, or a combination thereof), and in the liquid crystal layer Reflective means (for example, a reflective film or a reflective electrode) is arranged in at least one of the regions showing different orientation states, and the region showing the different orientation states includes a reflective display unit that performs reflective display and a transmission that performs transmissive display. It has the structure used for the display part.

  According to the above configuration, the liquid crystal alignment has different alignment states at the same time. For example, when a dye such as a dichroic dye is used for display, light absorption (absorption rate) and optical anisotropy are used. In some cases, the magnitude of the modulation amount of each optical physical quantity such as a phase difference can be changed for each region having a different liquid crystal alignment. For this reason, according to said structure, the transmittance | permeability or reflectance based on the magnitude | size of the modulation amount of the optical physical quantity according to the orientation state of a liquid crystal layer can be obtained, and, thereby, a transmissive display part and a reflective display part Thus, it is possible to set the optical parameters independently. Therefore, according to the above configuration, there is no parallax, a high contrast ratio can be realized, and it is possible to improve visibility when the surroundings are dark, and good visibility even when ambient light is strong Can be obtained. Therefore, according to the above configuration, a transflective liquid crystal display device that is excellent in visibility, capable of high-resolution display, and can use both reflected light and transmitted light for display is provided. be able to.

  Furthermore, the second liquid crystal display device has a configuration in which, in the first liquid crystal display device, the alignment mechanism is a display content rewriting means for rewriting the display content as time passes.

  According to the above configuration, the display content rewriting unit and the alignment mechanism can be realized by the same unit, and the first liquid crystal display device can be obtained without adding a new configuration. In this case, the display content rewriting means used for taking a plurality of states with different liquid crystal orientations is an electric liquid crystal orientation control means that is currently widely used to rewrite the display contents as time passes. That is, it goes without saying that various means used for voltage application, such as electrodes, can be used. In this case, for example, by using different electrodes for the transmissive display unit and the reflective display unit, or by changing the voltage itself between the transmissive display unit and the reflective display unit, the liquid crystal layer has different alignment states. A plurality of regions can be provided.

  In addition, when the degree of modulation of each optical physical quantity such as the light absorption amount and the phase difference due to optical anisotropy is changed independently between the reflective display unit and the transmissive display unit, the alignment direction of the liquid crystal due to voltage application Even when the entire region for use in displaying the liquid crystal layer is substantially the same, the region where the liquid crystal layer thickness of the liquid crystal layer is different is substantially the same as when the orientation direction of the liquid crystal layer is changed in the region. Has an effect. In particular, in the GH method using a dye such as a dichroic dye and the polarizing plate method using birefringence and optical rotation phenomenon, the light absorption and birefringence phenomena generated in the liquid crystal layer are as follows. These are phenomena associated with the propagation of light, and each phenomenon has a relationship between the propagation distance of light in the liquid crystal layer and the degree of those phenomena. Further, since the display light passes twice through the liquid crystal layer in the reflective display portion and only once through the liquid crystal layer in the transmissive display portion, the thickness of the liquid crystal layer is substantially the same when the liquid crystal orientation is substantially the same. However, when the reflective display unit and the transmissive display unit are set in the same manner, sufficient brightness and contrast ratio cannot be obtained, and the above-described problem cannot be solved.

  Therefore, the third liquid crystal display device includes a liquid crystal display element having a pair of substrates having alignment means (for example, an alignment film) on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates. In the liquid crystal display device, a region used for display in the liquid crystal layer is formed of a region having at least two different liquid crystal layer thicknesses, and each region having the different liquid crystal layer thickness is transmitted through the reflective display unit. In addition to being used in the display unit, at least the reflective display unit is provided with a reflecting means (for example, a reflective film or a reflective electrode), and the liquid crystal layer thickness of the reflective display unit is smaller than the transmissive display unit. Yes.

  According to the above configuration, it is possible to obtain a transmittance or a reflectance based on the magnitude of the modulation amount of the optical physical quantity in the regions having different liquid crystal layer thicknesses. Can be set independently. Therefore, according to the above configuration, there is no parallax, a high contrast ratio can be realized, and it is possible to improve visibility when the surroundings are dark, and good visibility even when ambient light is strong Can be obtained. Therefore, according to the above configuration, a transflective liquid crystal display device that is excellent in visibility, capable of high-resolution display, and can use both reflected light and transmitted light for display is provided. be able to.

  A fourth liquid crystal display device according to any one of the first to third liquid crystal display devices, wherein the contact surface is in contact with a region used for displaying the liquid crystal layer on at least one of the pair of substrates. The upper region has a configuration in which alignment means is applied so as to give at least two different alignment directions to the alignment of the liquid crystal layer interface in contact therewith.

  As described above, as means for having liquid crystal alignments having different alignment states at the same time, for example, in addition to the display content rewriting means, for example, at least two different alignment directions are applied to the interface on the substrate in contact with the liquid crystal layer. An alignment film or the like that has been subjected to an alignment treatment so as to give to the alignment at the interface of the liquid crystal layer in contact therewith can be used. In this way, the alignment means is provided so that at least two different alignment directions are given to the alignment of the liquid crystal layer interface in contact with the region on the contact surface in contact with the region used for display of the liquid crystal layer on the substrate surface. When the voltage is applied, the liquid crystal layer exhibits at least two different alignment states at the same time in any and different regions for use in display in the liquid crystal layer, and the alignment in the liquid crystal layer Reflective display and transmissive display can be performed in regions having different states.

  In this case, by changing the elevation angle of the liquid crystal orientation relative to the substrate and its azimuth angle, both the orientation of the liquid crystal that determines the optical characteristics and the orientation change when a voltage is applied can be changed. It is possible to perform display suitable for each display between the display unit and the transmissive display unit.

  According to the above-described means and orientation mechanism, both the reflective display unit and the transmissive display unit can achieve good display. However, color display (color display) or black-and-white display is performed, or reflective display is performed. Depending on the desired display, such as whether the display is based on the main display or the display is based on the transmissive display, there is an optimum ratio for a good display in the ratio between the reflective display portion and the transmissive display portion.

  That is, in the fifth liquid crystal display device, in the first to fourth liquid crystal display devices, the ratio of the area of the reflective display portion to the total area of the reflective display portion and the transmissive display portion is 30%. As described above, the configuration is 90% or less.

  According to the above configuration, when both the reflective display unit and the transmissive display unit perform color display, both the reflective display unit and the transmissive display unit can perform good display.

  Further, from the viewpoint of visibility, it is desirable that display contents are not inverted between the reflective display portion and the transmissive display portion. This is because the display contrast ratio increases depending on the intensity of the ambient light if the display contents are inverted between the reflective display and the transmissive display in a situation where the lighting environment changes or the change in the lighting environment is difficult to predict. This is because of the fluctuation, and from the viewpoint of visibility, such a change in contrast ratio is a phenomenon similar to that of washout, which causes a significant deterioration in visibility.

  Therefore, when the transmissive display unit is bright display, the reflective display unit simultaneously displays bright display, and when the transmissive display unit is dark display, the reflective display unit displays dark display at the same time to ensure visibility. It is very important.

  For this reason, in the sixth liquid crystal display device, in any of the first to fifth liquid crystal display devices, when the transmissive display portion is brightly displayed, the reflective display portion is simultaneously brightly displayed and the transmissive display portion is darkened. At the time of display, the reflective display unit is darkly displayed.

  According to the above configuration, the sixth liquid crystal display device includes the configuration of the first or third liquid crystal display device, so that the reflective display unit displays bright simultaneously when the transmissive display unit displays bright. When the transmissive display portion is dark, the reflective display portion can be dark. In particular, according to the liquid crystal display device, even if the display contents are inverted between the reflective display unit and the transmissive display unit as they are, for example, the display content rewriting means is used for the orientation mechanism, By individually controlling rewriting of display contents with the transparent display unit, the display can be easily aligned. Therefore, according to said structure, favorable visibility can be ensured.

  In addition, the seventh liquid crystal display device has a configuration in which the liquid crystal layer is made of a liquid crystal composition in which a dichroic dye is mixed in the liquid crystal in any of the first to sixth liquid crystal display devices. is doing.

  According to said structure, the said liquid-crystal layer optimizes the light absorption amount by a reflective display part and a transmissive display part by comprising the liquid crystal composition formed by mixing the dichroic pigment | dye in a liquid crystal. can do.

  In addition, as a display method for performing good display in both the reflective display portion and the transmissive display portion, it is also effective to use a method that utilizes birefringence or optical rotation for display using a polarizing plate.

  For this reason, in the eighth liquid crystal display device, in any one of the first to seventh liquid crystal display devices, a polarizing plate is disposed on the non-contact surface side with the liquid crystal layer in at least one of the pair of substrates. It has the structure which is made.

  According to said structure, birefringence can be optimized by a reflective display part and a transmissive display part, and a favorable display can be performed. At this time, in order to secure a sufficient display in the transmissive display unit in the third liquid crystal display device using a polarizing plate system for the reflective display unit, not only on the display surface side but also on the light incident side of the transmissive display unit. It is necessary to have a polarizing plate.

  In the eighth liquid crystal display device, the amount of change in the phase difference of the light caused by the orientation change due to the voltage of the liquid crystal layer is set so as to be suitable for light traveling back and forth in the liquid crystal layer in the reflective display unit, and the transmissive display unit Then, it is desirable to switch the display so as to be suitable for light transmitted through the liquid crystal layer.

  For this reason, the ninth liquid crystal display device includes, in the eighth liquid crystal display device, voltage application means (for example, an electrode) for applying a voltage to the liquid crystal layer, and the voltage application means is a reflective display unit at the time of voltage application. The phase difference of the display light on the reflecting means is approximately 90 degrees between the bright display and the dark display, and the phase difference of the display light emitted from the liquid crystal layer in the transmissive display portion is bright. A voltage is applied so that there is a difference of approximately 180 degrees between display and dark display.

  In this case, specifically, the liquid crystal orientation in the liquid crystal layer is such that the liquid crystal layer has a twist angle of 60 degrees or more and 100 degrees or less between the pair of substrates as shown in a tenth liquid crystal display device. Preferably, the liquid crystal layer is twist-aligned, or the liquid crystal layer is twist-aligned between the pair of substrates at a twist angle of 0 ° to 40 °, as shown in the eleventh liquid crystal display device. .

  By configuring the liquid crystal display device so that the liquid crystal layer is twist-aligned between the pair of substrates at a twist angle of 60 degrees or more and 100 degrees or less, in the liquid crystal layer of the transmissive display portion, the orientation of the liquid crystal The change in polarization close to the optical rotation according to the twist of can be used for display, and the reflection display unit can use the change in polarization by the control of optical rotation and retardation for display.

  Further, the liquid crystal layer is configured so that the liquid crystal layer is twist-aligned between the pair of substrates with a twist angle of 0 degree or more and 40 degrees or less. In the liquid crystal layer of the display unit, the change in retardation can be used for display.

  Therefore, the tenth liquid crystal display device has a configuration in which the liquid crystal layer is twist-aligned between the pair of substrates with a twist angle of 60 degrees or more and 100 degrees or less.

  The eleventh liquid crystal display device has a configuration in which the liquid crystal layer is twist-aligned between the pair of substrates at a twist angle of 0 ° to 40 °.

  According to the ninth to eleventh liquid crystal display devices, the reflective display unit and the transmissive display unit can obtain a change amount of the phase difference suitable for the reflective display or the transmissive display, respectively. The display can be switched.

  Further, in any of the first to sixth, eighth, or ninth liquid crystal display devices, sufficient change in the orientation of the liquid crystal can be achieved even if the orientation is changed only in a plane parallel to the substrate. Is possible.

  That is, the twelfth liquid crystal display device is the liquid crystal display device of any one of the first to sixth, eighth, or ninth, wherein the liquid crystal display element is at least one of the reflective display portion and the transmissive display portion. The liquid crystal molecules are rotated in parallel with the substrate to change the alignment state of the liquid crystal layer for display.

  Furthermore, according to the following configuration, the in-plane is obtained by actively utilizing the insufficient liquid crystal alignment that causes the low light transmittance, which is a problem of the conventional in-plane switching method, as a reflective display. The low light use efficiency of the switching method can be overcome.

  That is, the thirteenth liquid crystal display device is the twelfth liquid crystal display device, wherein the liquid crystal display element includes voltage applying means for generating an electric field in the liquid crystal layer in an in-plane direction of the substrate, the reflective display portion, and the transmissive display. It has the structure provided corresponding to either one of the parts.

  Further, the alignment of the liquid crystal layer may be a parallel alignment that has been conventionally used for display, but may also be a vertical alignment in which the liquid crystal is aligned perpendicular to the substrate.

  In a fourteenth liquid crystal display device according to any one of the first to ninth, twelfth, or thirteenth liquid crystal display devices, at least one of the pair of substrates is the surface of the contact surface with the liquid crystal layer. A region corresponding to at least one of the reflective display portion and the transmissive display portion is provided with an alignment film having a vertical alignment property.

  As described above, when the substrate includes an alignment film having a vertical alignment and the liquid crystal is aligned vertically with respect to the substrate, there is an advantage that the contrast ratio of the display is improved, and In the first to ninth, twelfth, or thirteenth liquid crystal display devices, the liquid crystal display device works effectively for good display.

  The fifteenth liquid crystal display device according to any one of the first to fourteenth liquid crystal display devices, wherein at least one of the pair of substrates is at least a reflective display of the reflective display portion and the transmissive display portion. An insulating film is provided in a region corresponding to the portion, and the insulating film is formed such that the thickness of the region corresponding to the reflective display portion is larger than the region corresponding to the transmissive display portion. have.

  That is, the liquid crystal display device has an insulating film on at least one substantially smooth substrate that sandwiches the liquid crystal layer, and the insulating film is a region corresponding to the transmissive display portion and a region corresponding to the reflective display portion. The insulating layer is formed only in the region corresponding to the reflective display portion, and the insulating film is not formed in the region corresponding to the transmissive display portion.

  According to the above configuration, the liquid crystal display device has at least two different liquid crystal layer thicknesses used for display in the liquid crystal layer (that is, liquid crystal displays having different liquid crystal layer thicknesses between the reflective display unit and the transmissive display unit). Device) can be obtained easily.

  The insulating film not only functions as a liquid crystal layer thickness adjusting means, but also drives the liquid crystal layer by forming a display electrode on the surface of the reflective display portion where the insulating film is in contact with the liquid crystal layer. A voltage can be applied to the liquid crystal layer without loss.

  In this case, a light-reflective film is formed as a reflecting means on a substrate disposed opposite to the substrate on the display surface side, and the light-reflective film has a concavo-convex structure. Effective as a means for preventing specularity of reflective display without impairing the resolution without impairing the performance, and the insulating film has a concavo-convex structure similar to the concavo-convex structure of the light-reflecting film. The film having light reflectivity can be easily formed.

  In addition, when performing color display using each of the above liquid crystal display devices, it is important to design not only the liquid crystal layer but also a color filter layer that is important for color development. According to the study by the inventors of the present application, there are two main types of usage of the transflective liquid crystal display device.

  One is that the transmissive display is mainly used in normal use, and the reflective display is additionally used to prevent washout in an illumination environment with very strong ambient light. Compared to only liquid crystal display devices, it is a usage mode mainly for transmissive display, which ensures a great variety of usable lighting environments, and the other is less power consumption in normal use Taking advantage of the nature of reflective display, and in a low-light environment, a lighting device called a backlight is turned on and used to secure a great variety of usable environments as in the previous usage mode. This is a usage mode mainly composed of reflective display.

  In the above usage pattern (usage pattern mainly including transmissive display), at least one of the pair of substrates in the region corresponding to the transmissive display unit is transmitted in one of the regions constituting the display region of each pixel. Disclosed is a liquid crystal display device that can display color light with high visibility and can use both reflected light and transmitted light for display by arranging color filters having colors. Can do.

  When performing color display in this way, each pixel is provided with a color filter having a transmissive color at least in the transmissive display unit, and the color filter is not used in the reflective display unit, or reflective display is performed. It is particularly effective to arrange a color filter having the same brightness as that of the color filter arranged in the transmissive display unit, or a color filter having a transmissive color having a higher brightness than that of the color filter arranged in the transmissive display unit.

  This is because, when performing color display, if the color filter of the transmissive display unit is used as it is for the reflective display unit, the brightness is insufficient, and when performing color display also on the reflective display unit, the area not using the color filter is reflected. By providing a color filter having a transmissive color higher in brightness than the transmissive display unit on the reflective display unit, the brightness can be compensated for, and color display is also possible for reflective display. In addition, the reflectance necessary for the reflective display portion can be ensured.

  In the reflective display unit, it is desirable to dispose a color filter having a transmissive color with higher brightness than the transmissive display unit in consideration of the display light passing through the color filter twice.

  Further, in a usage mode mainly for transmissive display, when the reflective display unit has a region where no color filter is provided, the display voltage signal necessary for transmissive display is a signal suitable for color display. The display voltage signal necessary for the display is a signal suitable for monochrome display in an example in which no color filter is used in the reflective display portion. Therefore, when the reflective display unit is not provided with a color filter, the proportion of pixels of each color contributing to the brightness is proportional to the luminous transmittance of each color in the transmissive display unit, but is equal for each color in the reflective display unit. Therefore, when the reflective display unit is not provided with a color filter, the area of the reflective display unit where no color display is performed is set in accordance with the luminous transmittance of each color of the color filter used for transmissive display. It is desirable to change.

  That is, in the sixteenth liquid crystal display device, in any one of the first to fifteenth liquid crystal display devices, in one of the pair of substrates, the transmissive display unit in the region constituting the display region of each pixel. A color filter having a transmissive color is arranged in a corresponding region, and at least a part of a region corresponding to the reflective display portion in a region constituting the display region is provided in a region corresponding to the transmissive display portion in the substrate. The color filter having the same brightness as the arranged color filter is arranged.

  According to the above configuration, brightness can be compensated, color display can be performed not only for transmissive display but also for reflective display, and the necessary reflectance for the reflective display unit can be ensured. In addition, a transflective liquid crystal display device capable of color display can be provided.

  In addition, the seventeenth liquid crystal display device according to any one of the first to fifteenth liquid crystal display devices may be a region corresponding to a transmissive display unit in a region constituting a display region of each pixel in one of the pair of substrates. In addition, a color filter having a transmissive color is disposed, and at least a part of the region corresponding to the reflective display portion among the regions constituting the display region is disposed in the region corresponding to the transmissive display portion in the substrate. It has a configuration in which a color filter having a transmission color having a higher brightness than the color filter is arranged.

  According to the above configuration, when color display is performed, brightness can be compensated, color display can be performed not only for transmissive display but also for reflective display, and necessary reflectance for the reflective display unit can be ensured. In addition, it is possible to provide a transflective liquid crystal display device mainly including transmissive display and capable of color display. In this case, the display light passes through the color filter twice in the reflective display section. For this reason, in the region corresponding to the reflective display portion, by arranging a color filter having a transmission color higher in brightness than the color filter disposed in the region corresponding to the transmissive display portion in the substrate, the brightness is further increased. A better color display can be performed.

  Further, the eighteenth liquid crystal display device according to any one of the first to seventeenth liquid crystal display devices, wherein at least transmissive display is performed among regions constituting a display region of each pixel in one of the pair of substrates. A color filter having a transmission color is arranged in an area corresponding to the area, and the area of the area where the color display of the reflection display section is not performed is set according to the luminous transmittance of the transmission color of the color filter. It has the composition which is.

  According to said structure, the ratio which the pixel of each color contributes to the brightness can be changed with the luminous transmittance of each color, As a result, a favorable display is realizable.

  Further, in the second usage pattern (usage pattern mainly using reflective display), at least one of the pair of substrates corresponding to the reflective display portion in the region constituting the display region of each pixel on one substrate. A liquid crystal display device that can display both reflected light and transmitted light for display with excellent visibility and high-resolution color display by arranging a color filter having a transmission color in the region. Can be provided.

  When performing color display in this way, each pixel is displayed with a color filter having a transparent color at least in the reflective display portion, and the color filter is not used in the transparent display portion. Alternatively, it is particularly effective to arrange a color filter having the same saturation as that of the color filter arranged in the reflective display unit or having a transmission color with a higher saturation than at least a part of the transmissive display unit.

  In the usage mode mainly for reflective display, when the black and white display is performed without using the color filter in the transmissive display unit, the light transmittance increases, so that the transmissive display unit can be set smaller. . Thereby, the area of a reflective display part can be ensured more, and a more favorable display can be obtained in the reflective display at the time of normal use.

  Further, in the usage mode mainly including the reflective display, the area of the transmissive display portion where no color display is performed is changed according to the luminous transmittance of each color of the color filter used for the reflective display. The contribution of the transmissive display unit to the brightness of the monochrome display can be appropriately set in consideration of the luminous transmittance.

  That is, the nineteenth liquid crystal display device according to any one of the first to fifteenth liquid crystal display devices, at least a reflective display portion of a region constituting a display region of each pixel in one of the pair of substrates. Is provided with a color filter having a transmissive color.

  According to the above configuration, it is possible to provide a liquid crystal display device that is excellent in visibility and capable of performing high-resolution color display when performing display mainly of reflective display. In this case, in particular, the light transmittance is increased by performing color display in the reflective display unit and performing monochrome display in the transmissive display unit without using a color filter. For this reason, in such a case, it is possible to set the transmissive display portion to be smaller, to secure a larger area of the reflective display portion, and to provide a better display in the reflective display during normal use. Obtainable.

  Further, in the twentieth liquid crystal display device, in the nineteenth liquid crystal display device, the area of the transmissive display portion where no color display is performed is set in accordance with the luminous transmittance of the transmissive color of the color filter. It has a configuration.

  According to the above configuration, when performing display mainly with reflective display, it is possible to appropriately set the contribution to the brightness from the monochrome display of the transmissive display unit in each pixel in consideration of the luminous transmittance. Therefore, a better display can be obtained.

  Further, the twenty-first liquid crystal display device according to any one of the first to fifteenth liquid crystal display devices, of the pair of substrates, an area corresponding to the reflective display portion in an area constituting a display area of each pixel. In addition, a color filter having a transmission color is arranged, and at least a part of a region corresponding to the transmissive display unit among the regions constituting the display region is arranged in a region corresponding to the reflective display unit in the substrate The color filter has a configuration in which a color filter having a transmitted color whose saturation is equal to or higher than that of the color filter is arranged.

  According to the above configuration, it is possible to provide a transflective liquid crystal display device mainly composed of reflective display, which can perform good color display in both the reflective display portion and the transmissive display portion.

  In addition, since the liquid crystal display device includes the reflective display unit as described above, it has a feature of low power consumption in the conventional reflective liquid crystal display device. However, using illumination light that consumes a large amount of power and keeping it in a lit state causes an increase in power consumption.

  Therefore, the twenty-second liquid crystal display device includes any one of the first to twenty-first liquid crystal display devices, and includes an illumination device that makes light incident on the liquid crystal display element from the back surface of the liquid crystal display element, and the illumination device includes: It has a configuration that also serves as display surface luminance changing means for changing the luminance of the display surface.

  According to said structure, coexistence with low power consumption and visibility can be aimed at by changing the brightness | luminance of a display surface with an illuminating device.

  Further, the twenty-third liquid crystal display device is the twenty-second liquid crystal display device, wherein the lighting device has a configuration in which the luminance of the display surface is changed so that the perceived lightness is not less than 10 brills and less than 30 brills according to the adaptation luminance. Have.

  The perceptual lightness is defined by the adaptation luminance and the luminance of the display surface. At this time, the above-described perceptual lightness can be obtained by the lighting device being turned on / off or changing the intensity of illumination according to the display content of the liquid crystal display device or the adaptation luminance that changes depending on the viewing environment such as lighting. Changing the luminance of the display surface so as to be obtained is very preferable for achieving both low power consumption and visibility. In particular, when the illuminating device is controlled from the outside of the liquid crystal display element by a press coordinate detection type input means such as a touch panel, the above effect becomes even more remarkable.

  Moreover, according to said structure, the visibility in the condition where the transmissive display mainly contributes to a display can be improved, favorable visibility can be implement | achieved, and low power consumption is achieved. be able to.

  Further, in the transflective liquid crystal display device as described above, it is easy to use a press coordinate detection type input means such as a touch panel as compared with a reflective liquid crystal display device using a so-called front light. There is a big advantage. Therefore, realizing a transflective and good display using such a pressed coordinate detection type input means is effective for a liquid crystal display device with a low power consumption and an integrated input device.

  That is, the twenty-fourth liquid crystal display device is a press coordinate detection type input for detecting a coordinate position pressed by being pressed on the display surface in any one of the first to twenty-third liquid crystal display devices. It has the structure which comprises the means.

  Therefore, according to the above configuration, it is possible to provide a favorable liquid crystal display device with low power consumption integrated with an input device.

  Furthermore, when such a pressed coordinate detection type input means is used, it is easily detected by the signal of the pressed coordinate detection type input means that the observer is using the display device. Therefore, changing the brightness of the display device by changing the brightness of the lighting device that influences the power consumption of the liquid crystal display device and changing the liquid crystal orientation achieves both a reduction in power consumption and good visibility. It is effective for.

  Therefore, the twenty-fifth liquid crystal display device is provided with a pressed coordinate detection type input unit that is arranged so as to overlap the display surface and detects the pressed coordinate position in the twenty-second or twenty-third liquid crystal display device. And the said illuminating device has the structure which changes the brightness | luminance of a display surface in response to the output signal of the said press coordinate detection type | mold input means.

  According to said structure, since it is easily detected that the observer is using the display apparatus by the signal of the said press coordinate detection type input means, the power consumption of a liquid crystal display device influences according to this signal. If the luminance of the lighting device is changed and the luminance of the display surface is changed, both reduction in power consumption and good visibility can be achieved.

  The twenty-sixth liquid crystal display device includes a pressed coordinate detection type input unit that is arranged so as to overlap the display surface and detects a pressed coordinate position in the first or second liquid crystal display device. The alignment mechanism is configured to change the alignment state of the liquid crystal layer in at least one of the reflective display portion and the transmissive display portion in conjunction with the output signal of the pressed coordinate detection type input means.

  According to the above configuration, since it is easily detected that the observer is using the display device based on the signal of the pressed coordinate detection type input means, if the liquid crystal alignment is changed according to this signal, the power consumption Reduction and good visibility can be achieved at the same time.

  When the liquid crystal display device includes both the pressed coordinate detection type input unit and the polarizing plate, the pressed coordinate detection type input unit and the polarizing plate include a polarizing plate, a pressed coordinate detection type input unit, and a liquid crystal display element. Arranged in this order.

  That is, the twenty-seventh liquid crystal display device is a press coordinate detection type input for detecting a coordinate position pressed by being pressed on the display surface in any one of the first to twenty-sixth liquid crystal display devices. Means and a polarizing plate, and the polarizing plate, the pressed coordinate detection type input means, and the liquid crystal display element are arranged in this order.

  According to the above configuration, it is possible to provide a liquid crystal display device with a low power consumption, which is integrated with an input device and includes a polarizing plate and a pressed coordinate detection type input unit and uses birefringence for display.

  Further, by arranging the polarizing plate, the pressed coordinate detection type input means, and the liquid crystal display element in this way, absorption by the polarizing plate absorbs unnecessary reflected light by the pressed coordinate detection type input means, and the unnecessary reflection. Light can be reduced. Therefore, according to said structure, the visibility of a liquid crystal display device can be improved and favorable visibility is implement | achieved.

It is principal part sectional drawing of the liquid crystal display device which concerns on Embodiment 1 of this invention. 3 is a display characteristic diagram of the liquid crystal display device described in Example 1. FIG. 10 is a display characteristic diagram of a liquid crystal display device described in Comparative Example 2 and Comparative Example 3. FIG. It is principal part sectional drawing of the liquid crystal display device which concerns on Embodiment 2 of this invention. It is a figure explaining the definition of a rubbing crossing angle. 6 is a display characteristic diagram of a liquid crystal display device described in Example 2. FIG. 6 is a display characteristic diagram of the liquid crystal display device described in Example 3. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Example 4. FIG. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Example 5; 10 is a display characteristic diagram of the liquid crystal display device described in Example 6. FIG. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Example 7; 10 is a display characteristic diagram of the liquid crystal display device described in Comparative Example 3. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Example 8. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Comparative Example 4. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Comparative Example 5. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Example 9. FIG. It is an alignment treatment process figure of the board | substrate used for the liquid crystal display device concerning Embodiment 4 of this invention. (A)-(e) is a cross-sectional schematic diagram which shows roughly the orientation processing process shown in FIG. FIG. 10 is a display characteristic diagram of the liquid crystal display device described in Example 10; FIG. 20 is a display characteristic diagram of the liquid crystal display device described in Example 11; (A) is principal part sectional drawing at the time of the voltage non-application of the liquid crystal display device concerning Example 12, (b) is principal part sectional drawing at the time of the voltage application of the liquid crystal display device shown to (a). . FIG. 20 is a display characteristic diagram of the liquid crystal display device described in Example 12; (A) is a principal part top view of the TFT element substrate for implement | achieving the transmissive main body transflective liquid crystal display device concerning Embodiment 7 of this invention, (b) is TFT shown to (a). It is a figure which shows the drive electrode of the reflective display part in an element substrate, (c) is a figure which shows the transparent pixel electrode in the TFT element substrate shown to (a). FIG. 24 is a cross-sectional view taken along line A-A ′ of the TFT element substrate shown in FIG. FIG. 24 is a cross-sectional view taken along the line B-B ′ of the TFT element substrate shown in FIG. FIG. 23A shows a color filter formed on a color filter substrate of a transmissive main body semi-transmissive liquid crystal display device according to Embodiment 7 of the present invention, and a reflective display portion in the TFT element substrate shown in FIG. FIG. 4 is a plan view of a main part of the transmission main body semi-transmission type liquid crystal display device, showing a positional relationship between a formed drive electrode and a transmission display opening by partially cutting the color filter substrate; These are sectional drawings of the color filter board | substrate shown to (a). FIG. 27 is a cross-sectional view of the main part of the liquid crystal display device shown in FIG. It is a principal part top view of the TFT element substrate for implement | achieving the reflection main body transflective liquid crystal display device concerning Embodiment 7 of this invention. (A) is formed in the color filter formed in the color filter substrate of the reflective main body transflective liquid crystal display device according to Embodiment 7 of the present invention, and in the reflective display portion in the TFT element substrate shown in FIG. FIG. 6 is a plan view of a principal part of the reflective main body transflective liquid crystal display device, showing a positional relationship of the drive electrode with a transmissive display opening by partially cutting the color filter substrate; It is sectional drawing of the color filter board | substrate shown to a). It is an isoline diagram which shows the relationship between the adaptation brightness | luminance which gives an equivalent perceived brightness, and sample brightness | luminance. It is a characteristic view which shows the relationship between the illumination intensity and the perceived brightness in the transflective liquid crystal display device concerning Embodiment 8 of this invention. It is principal part sectional drawing which shows schematic structure of the liquid crystal display device integrated with the input device concerning Embodiment 11 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid crystal layer 1a Liquid crystal molecule 2 Alignment film (alignment mechanism)
3 Alignment film (Orientation mechanism)
4 Substrate 5 Substrate 6 Electrode (Display content rewriting means, voltage applying means, orientation mechanism)
7 electrodes (display content rewriting means, voltage application means, orientation mechanism)
8 Reflective film (reflective means)
9 Reflective display unit 10 Transparent display unit 11 Insulating film (orientation mechanism)
12 Dichroic dye (Orientation mechanism)
13 Backlight (lighting device, display surface brightness changing means)
14 Polarizing plate 15 Polarizing plate 16 Phase difference compensation plate 17 Phase difference compensation plate 18 Pixel electrode (display content rewriting means, voltage application means)
19 Drive electrode (display content rewriting means, voltage application means)
19a Transparent display opening 20 Transparent pixel electrode (display content rewriting means, voltage application means)
21 TFT element 22 Drain terminal 23 Wiring 24 Wiring 25 Organic insulating film 26 Auxiliary capacitance portion 27 Auxiliary capacitance line 28 Source terminal 29 Substrate 40 Electrode substrate 41 Substrate 42 Alignment film (orientation mechanism)
42a Alignment treatment region 42b Alignment treatment region 52 Glass substrate 53 Comb electrode (display content rewriting means, voltage application means, orientation mechanism)
54 Substrate 61R Color filter 61G Color filter 61B Color filter 62 Glass substrate 71 Touch panel (pressing coordinate detection type input means)
72 transparent electrode layer 73 movable substrate 74 transparent electrode layer 75 support substrate 100 liquid crystal cell (liquid crystal display element)
101 Electrode substrate 102 Electrode substrate 200 Liquid crystal cell (liquid crystal display element)
201 Electrode substrate 202 Electrode substrate 501 Smoothing layer 502 Counter electrode (display content rewriting means, voltage application means)

Claims (4)

A liquid crystal display device comprising a liquid crystal display element having a pair of substrates having orientation means on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates,
The display surface side of the pair of substrates includes a reflective display portion in which reflective means is formed on the opposite substrate across the liquid crystal layer, and a transmissive display portion in which the reflective means is not formed,
The reflective display portion and the transmissive display portion simultaneously exhibit different liquid crystal orientations, and
A polarizing plate is disposed on the non-contact surface side with the liquid crystal layer in the pair of substrates,
A liquid crystal display device characterized in that when a voltage is not applied to the liquid crystal layer, dark display is performed on the reflective display portion and the transmissive display portion. A liquid crystal display device comprising a liquid crystal display element having a pair of substrates having orientation means on opposite surfaces and a liquid crystal layer sandwiched between the pair of substrates,
The display surface side of the pair of substrates includes a reflective display unit in which reflective means is formed on a substrate opposite to the liquid crystal layer, and a transmissive display unit in which the reflective unit is not formed,
The liquid crystal layer in the region used for display has at least two different liquid crystal layer thicknesses, and the liquid crystal layer thickness of the reflective display unit is greater than the liquid crystal layer thickness of the transmissive display unit among the different liquid crystal layer thicknesses. Also thin,
A polarizing plate is disposed on the non-contact surface side with the liquid crystal layer in the pair of substrates,
A liquid crystal display device characterized in that when a voltage is not applied to the liquid crystal layer, dark display is performed on the reflective display portion and the transmissive display portion.   3. A liquid crystal display device according to claim 1, wherein the alignment means is an alignment film having an action of aligning liquid crystal vertically with respect to the pair of substrates.   The liquid crystal display device according to claim 1, wherein the liquid crystal used in the liquid crystal layer is a liquid crystal having negative dielectric anisotropy.

Images