JP2008276271A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transflective liquid crystal display device in which retardation layers on the rear surface side can be cut down. <P>SOLUTION: The liquid crystal display device includes a pair of substrates 2, 6 and a liquid crystal layer 10 interposed between the substrates and has a reflective area and a transmissive area formed thereon. At least one of the substrates is provided with retardation films 7, 22, 32 whose phase differences differ between the reflective area and the transmissive area, formed thereon. The phase differences of the retardation films 7, 22 of the reflective area are larger than that of the retardation film 32 of the transmissive area. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a transflective liquid crystal display device having both a reflection part and a transmission part.

  Conventionally, as a display for a personal computer, a transmissive liquid crystal display that performs display using a backlight has been mainstream. However, in recent years, a display for a mobile electronic device such as a personal digital assistant (PDA) or a mobile phone is used. Reflecting liquid crystal display devices capable of reducing power consumption as compared with transmissive liquid crystal display devices have attracted attention as the demand for such devices has increased rapidly. This reflection type liquid crystal display device performs display by reflecting incident light from the outside with a reflection plate. Since a backlight is not required, the power consumption is saved, and the transmission type liquid crystal display device is reduced. There is an advantage that the electronic device can be driven for a long time as compared with the case where it is adopted.

  Since the reflective liquid crystal display device uses ambient light to display, assuming that it is used in dark conditions, install a front light on the display surface side of the panel so that light enters from the front light. Have been proposed. However, if the front light is installed on the display surface side, there is a disadvantage that the reflectance and contrast are lowered and the image quality is impaired.

  In order to solve this problem, a transflective liquid crystal display device has been developed in which a transmissive portion is provided in a part of the reflection plate of the pixel portion and the reflective type and the transmissive type coexist. In this method, since a backlight is installed on the opposite side of the display surface, good visibility can be obtained in both dark and bright areas without impairing the image quality as a reflection type, and high image quality. Can be realized. The basic configuration of a transflective liquid crystal display device is disclosed in, for example, Patent Documents 1 and 2 below.

JP 2000-29010 A JP 2000-35570 A

  As shown in FIG. 27, a conventional transflective liquid crystal display device 101 includes a reflective electrode 104 formed of a material having high reflectivity through an interlayer film 103 on one main surface side of a substrate 102, and a transmittance. A transparent electrode 105 formed of a high material, and a λ / 4 layer 106 and a polarizing plate 107 are laminated in this order on the other main surface side of the substrate 102. In addition, the liquid crystal display device 101 includes a counter electrode 107 on one main surface of the substrate 108 facing the substrate 102. Further, a λ / 4 layer 110 and a polarizing plate 111 are laminated in this order on the other main surface side of the substrate 108. Further, a liquid crystal layer 112 made of a liquid crystal material is provided between the reflective electrode 104 and the transparent electrode 105 and the counter electrode 109. In the liquid crystal display device 101 shown in FIG. 27, a total of two retardation layers are used, one on the front and one on the rear.

  Actually, in order to reliably suppress the influence of wavelength dispersion and realize a better black display, as shown in FIG. 28, a λ / 4 layer 106 and a λ / 2 layer 113 are combined on the substrate 102 side. In some cases, a total of four retardation layers may be used by combining the λ / 4 layer 110 and the λ / 2 layer 114 on the substrate 108 side.

  By the way, in the liquid crystal display device 101 shown in FIG. 27, the λ / 4 layer 110 is provided as a retardation layer on the entire surface of the substrate 108 serving as a display surface, thereby realizing reflection display while suppressing the influence of wavelength dispersion. . On the other hand, when transmissive display is realized, a retardation layer such as a λ / 4 layer is not necessary, but a λ / 4 layer 110 is present on the entire surface on the substrate 108 side which is a display surface for reflective display. Therefore, in order to compensate for the phase difference in the λ / 4 layer 110, it is necessary to use the λ / 4 layer 106 on the rear substrate 102 side. That is, in order to use one retardation layer, which is essentially unnecessary for transmissive display, on the display surface for reflection display, one sheet must be added on the rear surface in order to compensate for this phase difference.

  For the same reason, in the liquid crystal display device as shown in FIG. 28, two of the four retardation layers are for compensating for the phase difference of the retardation layer for reflection display, It is essentially unnecessary for display.

  As described above, the conventional transflective liquid crystal display device uses a larger number of retardation layers than the reflective liquid crystal display device and the transmissive liquid crystal display, which increases the cost and increases the thickness of the cell. I have inconvenience such as doing.

  SUMMARY OF THE INVENTION The present invention solves such a conventional problem, and an object of the present invention is to provide a transflective liquid crystal display device that can reduce, for example, a retardation layer on the rear surface side.

  In order to achieve the above-described object, a liquid crystal display device according to the present invention is a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and a reflection portion and a transmission portion are formed. A retardation layer is formed on the side. This phase difference layer has a larger phase difference in the reflection part than in the transmission part.

  The method for manufacturing a liquid crystal display device according to the present invention is a method for manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates, and a reflective portion and a transmissive portion are formed. A retardation layer is formed, and the retardation layer is patterned to leave the retardation layer at least in the reflection portion, and the phase difference of the retardation layer is made different between the reflection portion and the transmission portion.

  In the liquid crystal display device configured as described above, the phase difference layer required for the image display of the reflection portion is made different by making the phase difference of the phase difference layer formed on one substrate different between the reflection portion and the transmission portion. However, it does not function in the transmission part. For this reason, the retardation layer functions in the reflecting portion to obtain sufficient reflectivity, and in the transmissive portion, transmissive display can be achieved without adding a new retardation layer to compensate for the retardation of the retardation layer. Can be realized.

  In the liquid crystal display device according to the present invention, in a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates and a reflective portion and a transmissive portion are formed, a retardation layer is formed on at least one of the substrates. The phase difference layer is characterized in that a slow axis is different between the reflection part and the transmission part.

  In addition, a method for manufacturing a liquid crystal display device according to the present invention is a method for manufacturing a liquid crystal display device in which a liquid crystal layer is sandwiched between a pair of substrates, and a reflection portion and a transmission portion are formed. A retardation layer having different slow axes is formed between the reflection portion and the transmission portion.

  In the liquid crystal display device configured as described above, the phase difference required for the image display of the reflective portion is made different by making the slow axis of the retardation layer formed on one substrate different between the reflective portion and the transmissive portion. The layer is prevented from functioning in the transmissive part. For this reason, the retardation layer functions in the reflecting portion to obtain sufficient reflectivity, and in the transmissive portion, transmissive display can be achieved without adding a new retardation layer to compensate for the retardation of the retardation layer. Can be realized.

  In a conventional transflective liquid crystal display device, a circular polarizing plate is formed by combining a polarizing plate and a λ / 4 layer produced by batch rubbing treatment and exposure, thereby facilitating design on the optical configuration. Although the merit can be obtained, as described above, the number of used retardation layers increases, which causes an increase in cost. On the other hand, the present invention changes the phase difference between the transmission part and the reflection part, or by optimizing the combination of the rubbing direction and the transmission axis of the polarizing plate when forming the retardation layer, The conventionally required retardation layer can be reduced.

  Further, in the liquid crystal display element of the present invention, the transmission part can be set to the twisted nematic mode conventionally used in the transmission type liquid crystal display element. Therefore, high contrast can be obtained during transmissive display. In addition, the reflective part can be displayed in the electrolytic birefringence mode (ECB mode) with the same or different angle as the transmissive part, so the gap margin is widened and productivity is increased. Can be raised.

  As is clear from the above description, according to the liquid crystal display device of the present invention, the image of the reflective part is obtained by making the phase difference of the retardation layer formed on one substrate different between the reflective part and the transmissive part. The retardation layer necessary for display is prevented from functioning in the transmission part. For this reason, the retardation layer functions in the reflecting portion to obtain sufficient reflectivity, and in the transmissive portion, transmissive display can be achieved without adding a new retardation layer to compensate for the retardation of the retardation layer. Can be realized. Therefore, according to the present invention, it is possible to realize a transflective liquid crystal display device capable of realizing cell thinning and cost reduction by reducing the number of used retardation layers.

  Further, in the liquid crystal display device and the manufacturing method thereof according to the present invention, it is necessary for the image display of the reflective portion by making the slow axis of the retardation layer formed on one substrate different between the reflective portion and the transmissive portion. The retardation layer is made to not function in the transmission part. For this reason, the retardation layer functions in the reflecting portion to obtain sufficient reflectivity, and in the transmissive portion, transmissive display can be achieved without adding a new retardation layer to compensate for the retardation of the retardation layer. Can be realized. Therefore, according to the present invention, it is possible to realize a transflective liquid crystal display device capable of realizing cell thinning and cost reduction by reducing the number of used retardation layers.

  Furthermore, by adjusting the alignment direction inside the cell, the conventional optical rotation mode can be set at the transmission portion and the ECB mode at the reflection portion. As a result, a high contrast comparable to that of a normal twisted nematic can be realized in the transmission mode.

  Hereinafter, a liquid crystal display device to which the present invention is applied and a manufacturing method thereof will be described in detail with reference to the drawings.

<First Embodiment>
First, a first embodiment of a transflective liquid crystal display device to which the present invention is applied will be described. Although the liquid crystal display device according to the first embodiment will be described in detail later, the liquid crystal display device is basically characterized in that the phase difference of the retardation layer is different between the reflection portion and the transmission portion. A basic configuration of the liquid crystal display device according to the first embodiment will be described with reference to FIG.

  In the liquid crystal display device 1 shown in FIG. 1, one substrate 2 includes a reflective electrode 3 serving as a reflective portion formed of a material having high reflectance on one main surface side, and a transmissive portion formed of a material having high transmittance. And a polarizing plate 5 is disposed on the other main surface side. In addition, the other substrate 6 on the display surface side as ambient light enters is a reflection portion λ / 4 layer 7 as a retardation layer on a reflection portion on one main surface side facing the substrate 2, and a reflection portion and a transmission portion. The counter electrode 8 is provided in both regions, and a polarizing plate 9 is disposed on the other main surface side. A liquid crystal layer 10 made of a liquid crystal material is sandwiched between the substrate 2 and the substrate 6. Further, a backlight (not shown) for transmissive display is disposed outside the polarizing plate 5. The transmission axis of the polarizing plate 9 and the transmission axis of the polarizing plate 5 are set to be orthogonal. Further, the slow axis of the reflection part λ / 4 layer 7 which is a retardation layer is set at a predetermined angle with respect to the transmission axis or absorption axis of the polarizing plate 9 (here, for example, an angle of 45 ° with respect to the transmission axis). It is set to make.

  In the liquid crystal display device 1 of the first embodiment, the reflection part λ / 4 layer 7 is formed as a retardation layer in the reflection part, but no retardation layer is formed in the transmission part, and the reflection part And the transmission part have different phase differences. In other words, the reflection portion λ / 4 layer 7 functions in the reflection portion to obtain a phase difference necessary for reflection display, while no phase difference occurs in the transmission portion. With such a configuration, transmissive display is realized without adding a λ / 4 layer on the rear surface in order to compensate for a phase difference of the reflective portion λ / 4 layer 7 on the display surface side.

  The reflection part λ / 4 layer 7 which is a retardation layer may be formed outside the substrate 6, but is preferably formed on the liquid crystal layer 10 side as shown in FIG. The problem of parallax caused by the thickness of the substrate 6 can be suppressed as much as possible.

  The reflection part λ / 4 layer 7 which is a retardation layer is coated by applying a liquid crystal polymer on the substrate 6 after being subjected to an alignment process such as rubbing, and is patterned so as to leave the liquid crystal polymer only in the reflection part. Is obtained. More specifically, a photosensitive liquid crystal polymer is applied on the substrate 6 that has been subjected to the alignment treatment, and a retardation layer having a desired shape is obtained through an exposure process and a development process. Alternatively, a retardation layer may be obtained by applying a UV curable liquid crystal monomer exhibiting a nematic phase on the substrate 6 or an alignment film and irradiating with UV light to generate a liquid crystal polymer. The retardation of the retardation layer can be arbitrarily adjusted by changing the film thickness. In addition, as a phase difference layer, it is not limited to a liquid crystal polymer, The stretched film may be sufficient.

  A case where an image is actually displayed on the liquid crystal display device 1 shown in FIG. 1 will be described with reference to FIGS. In addition, in order to simplify description, illustration of the board | substrate 2 and the counter electrode 8 is abbreviate | omitted in FIG.2 and FIG.3. Further, when light passes through the liquid crystal layer 10 once without applying a voltage to the liquid crystal layer 10, the position of the liquid crystal layer 10 is set so as to have a phase difference of λ / 4 at the reflection portion and λ / 2 at the transmission portion. It is assumed that the phase difference is adjusted, the liquid crystal alignment when no voltage is applied is substantially parallel to the substrate 2 and the substrate 6, the alignment direction is parallel to the alignment direction of the reflective portion λ / 4 layer 7, and the polarization It is assumed that an angle of 45 ° is formed with respect to the transmission axis of the plate 9.

  First, a case where a voltage is not applied to the liquid crystal layer 10 and a bright display is performed will be described with reference to FIG.

  In the reflecting portion, ambient light incident from the substrate 6 side (display surface) becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 9. The linearly polarized light is incident on the reflection portion λ / 4 layer 7 to be circularly polarized light, and further converted into linearly polarized light by the liquid crystal layer 10 to reach the reflective electrode 3. The linearly polarized light whose traveling direction is reversed by the reflecting electrode 3 passes through the liquid crystal layer 10 again to become circularly polarized light, and this circularly polarized light passes again through the reflecting portion λ / 4 layer 7 and is parallel to the transmission axis of the polarizing plate 9. Linearly polarized light passes through the polarizing plate 9.

  In the transmissive portion, the light emitted from the substrate 2 side (rear surface) by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. Due to the liquid crystal layer 10 having the phase difference of λ / 2, the linearly polarized light becomes linearly polarized light orthogonal to the transmission axis of the polarizing plate 5, that is, linearly polarized light parallel to the transmission axis of the polarizing plate 9, and passes through the polarizing plate 9.

  Next, the case where a voltage is applied to the liquid crystal layer 10 for dark display will be described with reference to FIG.

  In the reflection part, the ambient light incident from the display surface becomes linearly polarized light that matches the transmission axis of the polarizing plate 9. This linearly polarized light is incident on the reflecting portion λ / 4 layer 7 to be circularly polarized light. Circularly polarized light reaches the reflective electrode 3 and is reflected by the liquid crystal layer 10 while maintaining almost the polarization state thereof. The reflected circularly polarized light is circularly polarized light whose rotational direction is reversed, and is again incident on the reflection part λ / 4 layer 7 through the liquid crystal layer 10 and converted into linearly polarized light orthogonal to the transmission axis of the polarizing plate 9, Absorbed by the polarizing plate 9.

  In the transmission part, the light irradiated from the rear surface by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. The linearly polarized light reaches the polarizing plate 9 while maintaining almost the polarization state in the liquid crystal layer 10 and is absorbed by the polarizing plate 9.

  As described above, the reflection portion λ / 4 layer 7 necessary for dark display of the reflection portion is not formed in the transmission portion. For this reason, in the reflection part, the reflection part λ / 4 layer 7 functions to obtain a sufficient reflectance, and in the transmission part, a new retardation layer for compensating the retardation of the retardation layer on the display surface side is provided. Transparent display can be realized without adding to the rear surface. Therefore, while achieving good display quality with high contrast in both reflective display and transmissive display, the retardation layer on the rear surface is no longer required, making the cell thinner and reducing the cost of the unnecessary retardation layer. Is done.

  In the above description, when a voltage is applied to the liquid crystal display device, the liquid crystal molecules of the liquid crystal layer are aligned substantially perpendicular to the substrate surface, and when no voltage is applied, the phase difference of λ / 4 and Although the configuration having a phase difference of λ / 2 at the transmission part has been described as an example, the liquid crystal display device of the present invention may be reversed. In other words, the configuration may be such that when a voltage is applied to the liquid crystal display device, the reflection portion has a phase difference of λ / 4 and the transmission portion has a phase difference of λ / 2.

  By the way, in the present embodiment, the retardation layer is not limited to a single layer of the reflection portion λ / 4 layer, and the wavelength dispersion in the reflection portion λ / 4 layer and the reflection portion λ / 4 layer is compensated. The structure which consists of two layers with a phase difference layer may be sufficient. The case where the retardation layer that compensates the chromatic dispersion of the reflection part λ / 4 layer is a λ / 2 layer will be described with reference to FIG. In FIG. 4, the same components as those of the liquid crystal display device 1 of FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the liquid crystal display device 21 of this application example, the retardation layer in the reflection portion has a two-layer structure of the reflection portion λ / 2 layer 22 and the reflection portion λ / 4 layer 7, and the retardation layer is formed in the transmission portion. The structure is not done.

  In addition to the effects of the above-described liquid crystal display device 1 as the basic structure, the liquid crystal display device 21 has a wideband wavelength dispersion when performing dark display by providing the above-described two-layer structure of the retardation layer of the reflecting portion. Light leakage can be eliminated and better image display can be realized.

  Further, in the liquid crystal display device 1 having the basic structure described above and the liquid crystal display device 21 of the application example, all of the retardation layer of the transmission portion is removed, but the present invention has a phase difference different from that of the reflection layer. The case where the retardation layer is formed in the transmission part is also included. A liquid crystal display device of still another application example will be described with reference to FIG. In FIG. 5, the same components as those of the liquid crystal display device 1 of FIG. 1 and the liquid crystal display device 21 of FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  Unlike the configuration of the liquid crystal display device 21 of FIG. 4, the liquid crystal display device 31 illustrated in FIG. 5 has a transmission portion retardation layer 32 formed on the substrate 6 on the liquid crystal layer 10 side. The retardation of the transmissive portion retardation layer 32 is determined in consideration of various characteristics of the liquid crystal layer 10 and is such that the residual phase difference when a voltage is sufficiently applied to the liquid crystal layer 10 is canceled. Preferably there is.

  Thereby, in addition to the effect of the liquid crystal display device 21 described above, the liquid crystal display device 31 can darken the dark display in the transmissive portion and realize a better image display.

  In this application example, the case where the retardation layer of the reflection portion has a two-layer structure of the reflection portion λ / 4 layer 7 and the reflection portion λ / 2 layer 22 is described as an example. Even if has a single-layer structure, the effect of forming the transmission portion retardation layer 32 can be obtained.

  Further, the liquid crystal display device of the present embodiment can be applied to a full-color liquid crystal display device 41 as shown in FIG.

  The liquid crystal display device 41 has color filters 42R, 42G, and 42B corresponding to the red, green, and blue dots on the liquid crystal layer 10 side of the substrate 6, and corresponds to the reflecting portions of the color filters 42R, 42G, and 42B. A reflective portion λ / 4 layer 7R, a reflective portion λ / 4 layer 7G, and a reflective portion λ / 4 layer 7B are formed as retardation layers on the region, and an overcoat layer 43 is interposed on the reflective portion retardation layer. A counter electrode 8 is formed.

  The liquid crystal display device 41 of this application example has a reflection part λ / 4 layer 7R, a reflection part λ / 4 layer 7G, a reflection part λ /, which are retardation layers, in accordance with the transmission wavelengths of the color filters 42R, 42G, and 42B. By changing the film thickness of the four layers 7B, it is assumed that the retardation layers of the respective parts have a retardation of λ / 4. Thereby, it is possible to suppress the influence of wavelength dispersion of each color and realize a better image display.

  In the above description, a liquid crystal display device having a configuration in which a retardation layer is formed on a substrate on the display surface side is taken as an example. However, the present invention is not limited to this, and the retardation layer is a backlight. It is only necessary that a retardation layer having a different phase difference is formed on at least one of the substrates, such as a configuration formed on the side substrate.

<Second Embodiment>
A second embodiment of a transflective liquid crystal display device to which the present invention is applied will be described. The liquid crystal display device according to the second embodiment is different from the first embodiment described above in the alignment direction of the liquid crystal layer between the reflection portion and the transmission portion (that is, the alignment direction of the liquid crystal molecules and the liquid crystal alignment). Yes, and other configurations are the same. The basic configuration of the liquid crystal display device of the second embodiment will be described with reference to FIG. In addition, the same code | symbol is attached | subjected about the structure similar to the liquid crystal display device 1 of FIG. 1, and detailed description is abbreviate | omitted. In addition, FIG. 7 shows an optical configuration of a reflection portion and a transmission portion together with a schematic cross-sectional view of a main part of the liquid crystal display device. The liquid crystal alignment on the substrate 6 side, and the liquid crystal alignment (lower) is the liquid crystal alignment on the substrate 2 side. In the optical configuration described below, the optical axis direction of the polarizing plates 5 and 9 indicates the transmission axis direction.

  That is, in the liquid crystal display device 1 ′ shown in FIG. 7, the liquid crystal alignment of the reflective portion is the same as that of the liquid crystal display device of FIG. 1, for example, in the state where no voltage is applied to the reflective portion liquid crystal layer 10 ′. Is set so as to form an angle of 45 ° with respect to the transmission axes of the polarizing plate 9 and the polarizing plate 5. In this state, the liquid crystal layer 10 ′ of the reflecting portion is adjusted so as to have a phase difference of λ / 4 when light passes through the liquid crystal layer 10 ′ once. It is the same.

  On the other hand, in the transmissive portion, the liquid crystal alignment on the substrate 6 side is parallel to the transmission axis of the polarizing plate 9 and the liquid crystal alignment on the substrate 2 side is By being parallel, it is set to be twisted nematic that can be twisted by 90 °.

  Further, in a state where a voltage is applied to the liquid crystal layer 10 ′, the liquid crystal molecules are aligned substantially perpendicular to the surfaces of the substrates 2 and 6 in both the reflection part and the transmission part.

  For this reason, in the liquid crystal display device 1 ′, the alignment film (not shown) on the surface facing the liquid crystal layer 10 ′ between the substrate 2 and the substrate 6 is subjected to alignment treatment as follows. That is, in the reflection part, the alignment films on the substrate 2 side and the substrate 6 side are aligned in a direction that forms an angle of 45 ° with respect to the transmission axes of the polarizing plate 5 and the polarizing plate 9. For this reason, as shown in the drawing, these alignment films may be oriented in a direction that forms an angle of 90 ° with respect to the reflective portion λ / 4 layer 7, or parallel to the reflective portion λ / 4 layer 7. Orientation treatment may be performed so that On the other hand, in the transmission part, the alignment film on the substrate 2 side is aligned in a direction parallel to the transmission axis of the polarizing plate 5, and the alignment film on the substrate 6 side is parallel to the transmission axis of the polarizing plate 9. Has been oriented.

  A case where an image is actually displayed on the liquid crystal display device 1 ′ shown in FIG. 7 will be described with reference to FIGS. 8 and 9. In order to simplify the description, the alignment films on the surfaces facing the substrate 2, the counter electrode 8, and the liquid crystal layer 10 ′ are omitted in FIGS. 8 and 9.

  First, a case where a voltage is not applied to the liquid crystal layer 10 ′ and a bright display is performed will be described with reference to FIG. 8.

  In the reflecting portion, ambient light incident from the substrate 6 side (display surface) becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 9. The linearly polarized light is incident on the reflection portion λ / 4 layer 7 to be circularly polarized light, and is further converted to linearly polarized light by the liquid crystal layer 10 ′ and reaches the reflective electrode 3. The linearly polarized light whose traveling direction is reversed by the reflective electrode 3 passes through the liquid crystal layer 10 ′ again to become circularly polarized light, and this circularly polarized light passes through the reflection part λ / 4 layer 7 again and passes through the transmission axis of the polarizing plate 9. It becomes parallel linearly polarized light and passes through the polarizing plate 9.

  In the transmissive portion, the light emitted from the substrate 2 side (rear surface) by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. By the liquid crystal layer 10 ′ in which the linearly polarized light is twisted nematic twisted by 90 °, the linearly polarized light orthogonal to the transmission axis of the polarizing plate 5, that is, the linearly polarized light parallel to the transmission axis of the polarizing plate 9 is obtained. pass.

  Next, the case where a voltage is applied to the liquid crystal layer 10 ′ for dark display will be described with reference to FIG. 9.

  In the reflection part, the ambient light incident from the display surface becomes linearly polarized light that matches the transmission axis of the polarizing plate 9. This linearly polarized light is incident on the reflecting portion λ / 4 layer 7 to be circularly polarized light. Circularly polarized light reaches the reflective electrode 3 and is reflected by the liquid crystal layer 10 ′ while maintaining almost the polarization state. The reflected circularly polarized light is circularly polarized light whose rotational direction is reversed, and is again incident on the reflection part λ / 4 layer 7 through the liquid crystal layer 10 and converted into linearly polarized light orthogonal to the transmission axis of the polarizing plate 9, Absorbed by the polarizing plate 9.

  In the transmission part, the light irradiated from the rear surface by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. The linearly polarized light reaches the polarizing plate 9 while maintaining almost the polarization state in the liquid crystal layer 10 and is absorbed by the polarizing plate 9.

  As described above, the liquid crystal display device 1 ′ having such a configuration is similar to the liquid crystal display device 1 of FIG. 1 in the first embodiment, in which the reflective portion λ / 4 layer necessary for dark display of the reflective portion. 7 is not formed in the transmission part, and the same effect as in the first embodiment can be obtained. In addition, since the liquid crystal alignment of the transmissive part is twisted nematic twisted by 90 °, display in the optical rotation mode is performed in the transmissive part, and display with better contrast can be performed. .

  In the above description, when a voltage is applied to the liquid crystal display device, the liquid crystal molecules of the liquid crystal layer are aligned substantially perpendicular to the substrate surface, and when no voltage is applied, a phase difference of λ / 4 is generated at the reflecting portion. An example of a configuration that has a twisted nematic structure that is twisted by 90 ° at the transmission portion is given as an example, but the liquid crystal display device of the present invention may be reversed. In other words, when a voltage is applied to the liquid crystal display device, the reflection portion may have a phase difference of λ / 4 and may be a twisted nematic that is twisted by 90 ° at the transmission portion.

  By the way, the second embodiment is not limited to the case where the retardation layer is composed of one layer of the reflection portion λ / 4 layer 7, and is similar to that described with reference to FIG. 4 in the first embodiment. Further, it may be configured by two layers of a reflection part λ / 4 layer and a retardation layer that compensates for chromatic dispersion in the reflection part λ / 4 layer. The case where the retardation layer that compensates the chromatic dispersion of the reflection part λ / 4 layer is a λ / 2 layer will be described with reference to FIG. In addition, in FIG. 10, the optical structure of a reflection part and a transmission part is shown with the principal part schematic sectional drawing of a liquid crystal display device. Further, the same components as those of the liquid crystal display device 21 of FIG. 4 and the liquid crystal display device 1 ′ of FIG. 7 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the liquid crystal display device 21 ′ of this application example, the retardation layer in the reflection part has a two-layer structure of the reflection part λ / 2 layer 22 and the reflection part λ / 4 layer 7, and the transmission part has a retardation layer. The structure is not formed. In this case, the reflection part λ / 2 layer 22 and the reflection part λ / 4 layer are configured such that the reflection part λ / 2 layer 22 and the reflection part λ / 4 layer 7 are combined to form a λ / 4 layer of the optical band. 7, the slow axis of each other is kept at 60 °, and the slow axis of the reflection part λ / 2 layer 22 is kept at 15 ° with respect to the transmission axis (or absorption axis) of the polarizing plate 9. It is assumed that the slow axis of the λ / 4 layer 7 is maintained at 75 ° with respect to the transmission axis (or absorption axis) of the polarizing plate 9.

  In this case, the liquid crystal alignment of the reflecting portion is adjusted so as to have a phase difference of λ / 4 when light passes through the liquid crystal layer 10 ′ once in a state where no voltage is applied to the liquid crystal layer 10 ′. Further, it is desirable to set it in the same direction as the slow axis of the reflection portion λ / 4 layer 7 or a direction close to a right angle so that the residual retardation when the voltage is applied can be adjusted by λ / 4.

  In the liquid crystal display device 21 ′ having the above-described two-layer structure of the retardation layer of the reflection portion, in addition to the effect of the above-described liquid crystal display device 1 ′ as the basic structure, when performing dark display, the reflection portion has a wide band. It is possible to perform display in the ECB mode in which light leakage due to wavelength dispersion is eliminated, and further excellent image display can be realized.

  In the second embodiment, the present invention is not limited to the case where only the liquid crystal layer 10 ′ in the transmissive part is twisted nematic, and the liquid crystal layer 10 ′ in the reflective part may be twisted nematic. A case where the liquid crystal layer 10 ′ of the reflection part is also twisted nematic will be described with reference to FIG. 11. In FIG. 11, the same components as those of the liquid crystal display device 21 'of FIG. 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The liquid crystal display device 21a of this application example is different from the liquid crystal display device 21 'described with reference to FIG. 10 in the liquid crystal alignment of the reflecting portion, and the other configurations are the same.

  In other words, in the liquid crystal display device 21a shown in FIG. 11, the liquid crystal alignment of the reflecting portion is set to be twisted nematic when no voltage is applied to the liquid crystal layer 10 '. For this reason, in the liquid crystal display device 21a, the alignment film (not shown) on the surface facing the liquid crystal layer 10 ′ between the substrate 2 and the substrate 6 forms a predetermined angle between the substrate 2 side and the substrate 6 side. It is assumed that it has been subjected to orientation treatment. This angle is a balance between the size of the cell gap and the birefringence of the liquid crystal layer 10 ′. When no voltage is applied to the liquid crystal layer 10 ′, light passes through the liquid crystal layer 10 ′ once. It is adjusted to have a phase difference of / 4.

  Further, in a state where a voltage is applied to the liquid crystal layer 10 ′, the liquid crystal molecules are aligned substantially perpendicular to the surfaces of the substrates 2 and 6 as described above.

  Thus, the effective phase difference of the liquid crystal layer of the reflective portion is reduced by setting the liquid crystal alignment of the reflective portion to twisted nematic. For this reason, the cell gap for setting the reflection part to have a phase difference of λ / 4 widens, and the margin for the cell gap is expanded. As a result, it becomes possible to improve the yield of the liquid crystal display device.

  Note that the liquid crystal display device of the second embodiment described above can be applied to a full-color liquid crystal display device in the same manner as the first embodiment. In the above description, a liquid crystal display device having a configuration in which a retardation layer is formed on a substrate on the display surface side is taken as an example. However, the present invention is not limited to this, and the retardation layer is a backlight. It is only necessary that a retardation layer having a different phase difference is formed on at least one of the substrates, such as a configuration formed on the side substrate.

  Moreover, each structure demonstrated in 2nd Embodiment can obtain the effect specific to the combined structure by combining each other.

<Third Embodiment>
Next, a third embodiment of a transflective liquid crystal display device to which the present invention is applied will be described. Although the liquid crystal display device according to the third embodiment will be described in detail later, the liquid crystal display device is basically characterized in that the slow axis of the retardation layer is different between the reflection portion and the transmission portion. A basic configuration of the liquid crystal display device of the third embodiment will be described with reference to FIG. In FIG. 12, the same components as those of the liquid crystal display device 1 of FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the liquid crystal display device 51 shown in FIG. 12, one substrate 2 includes a reflective electrode 3 serving as a reflective portion formed of a material having high reflectance on one main surface side through an interlayer film 52, and a material having high transmittance. The transparent electrode 4 serving as a transmission portion formed by the above-described method, the reflective electrode 3 and the alignment film 53 formed on the transparent electrode 4 are provided, and the polarizing plate 5 is disposed on the other main surface side. In addition, the other substrate 6 on the display surface side when ambient light is incident is the reflective portion λ / 4 layer as a retardation layer in the region of the reflective portion on one main surface side facing the substrate 2 through the alignment film 54. 7, a transmission part λ / 4 layer 55 in the transmission part region, a counter electrode 8 in both the reflection part and transmission part regions, and an alignment film 56 formed on the counter electrode 8. Is provided with a polarizing plate 9. A liquid crystal layer 10 made of a liquid crystal material is sandwiched between the substrate 2 and the substrate 6. Further, a backlight (not shown) for transmissive display is disposed outside the polarizing plate 5. The transmission axis of the polarizing plate 9 and the transmission axis of the polarizing plate 5 are set to be orthogonal. In addition, the slow axis of the reflection part λ / 4 layer 7 that is the retardation layer of the reflection part is set to make an angle of 45 ° with respect to the transmission axis of the polarizing plate 9.

  The direction of the slow axis of the transmission part λ / 4 layer 55 that is the retardation layer of the transmission part is different from the direction of the slow axis of the reflection part λ / 4 layer 7 that is the retardation layer of the reflection part. Specifically, the slow axis of the transmission portion λ / 4 layer 55 is parallel to the transmission axis of the polarizing plate 9 disposed on the substrate 6 serving as a display surface. The reflective portion λ / 4 layer 7 and the transmissive portion λ / 4 layer 55 are, for example, ultraviolet curable having a liquid crystal polymer or a nematic phase on an alignment film 54 that is divided on the substrate 6 by a reflective portion and a transmissive portion. Obtained by applying a liquid crystal monomer. Of course, it is also possible to perform alignment division by photo-alignment treatment. In this case, the alignment film 54 does not need to be provided.

  In the liquid crystal display device 51 of the third embodiment, the retardation layer formed on the entire surface of one substrate 6 is orientation-divided, and the reflection portion λ / 4 layer 7 and the transmission portion λ / 4 layer 55 are delayed. Since the phase axes are different, only the reflection portion λ / 4 layer 7 functions as a retardation layer. In other words, the transmission axis λ / 4 layer 55 has no effective phase difference because the slow axis of the transmission part λ / 4 layer 55 coincides with the transmission axis of the polarizing plate 9 on the front surface. With such a configuration, transmissive display is realized without adding a rear retardation layer in order to compensate for the retardation of the reflection portion λ / 4 layer 7.

  The reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55 that are retardation layers may be formed outside the substrate 6, but are formed on the liquid crystal layer 10 side as shown in FIG. It is preferable that the problem of parallax due to the thickness of the substrate 6 can be suppressed as much as possible.

  The reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55, which are retardation layers, are obtained by applying a liquid crystal polymer on the substrate 6 that has been subjected to an alignment process such as mask rubbing. More specifically, a photosensitive liquid crystal polymer is applied on the substrate 6 that has been subjected to the alignment treatment, and a retardation layer having a desired shape is obtained through an exposure process and a development process. Alternatively, a retardation layer may be obtained by applying a UV curable liquid crystal monomer exhibiting a nematic phase on the substrate 6 or an alignment film and irradiating with UV light to generate a liquid crystal polymer. Further, the reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55, which are retardation layers, can also be obtained by photo-aligning a film formed by applying a liquid crystal polymer. The retardation of the retardation layer can be arbitrarily adjusted by changing the film thickness. Moreover, as a phase difference layer, you may form with the stretched film.

  In the present embodiment, the direction of the slow axis of the retardation layer of the transmissive part is such that there is no effective phase difference of the retardation layer of the transmissive part. It may coincide with either the transmission axis or the absorption axis, or the transmission axis or the absorption axis of the polarizing plate on the rear surface.

  A case where an image is actually displayed on the above-described liquid crystal display device 51 shown in FIG. 12 will be described with reference to FIGS. In order to simplify the description, illustration of the substrate 2, the counter electrode 8, and each alignment film is omitted in FIGS. 13 and 14. In addition, when light passes through the liquid crystal layer 10 without applying a voltage to the liquid crystal layer 10, the thickness of the liquid crystal layer has a phase difference of λ / 4 at the reflection portion and λ / 2 at the transmission portion. The liquid crystal alignment when no voltage is applied is substantially parallel to the substrate 2 and the substrate 6, and the alignment orientation is at an angle of 45 ° with respect to the transmission axis of the polarizing plate 9. And

  First, a case where a voltage is not applied to the liquid crystal layer 10 and a bright display is performed will be described with reference to FIG.

  In the reflection part, the ambient light incident from the display surface becomes linearly polarized light that matches the transmission axis of the polarizing plate 9. The linearly polarized light is incident on the reflection portion λ / 4 layer 7 to be circularly polarized light, and further converted into linearly polarized light by the liquid crystal layer 10 to reach the reflective electrode 3. The linearly polarized light whose traveling direction is reversed by the reflecting electrode 3 passes through the liquid crystal layer 10 again to become circularly polarized light, and this circularly polarized light passes again through the reflecting portion λ / 4 layer 7 and is parallel to the transmission axis of the polarizing plate 9. Linearly polarized light passes through the polarizing plate 9.

  In the transmission part, the light irradiated from the rear surface by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. By the liquid crystal layer 10 having a phase difference of λ / 2, the linearly polarized light becomes linearly polarized light orthogonal to the transmission axis of the polarizing plate 5, that is, linearly polarized light parallel to the transmission axis of the polarizing plate 9, and the transmission portion λ / 4 layer 55 And passes through the polarizing plate 9 while maintaining almost the polarization state.

  Next, the case where a voltage is applied to the liquid crystal layer 10 for dark display will be described with reference to FIG.

  In the reflection part, the ambient light incident from the display surface becomes linearly polarized light that matches the transmission axis of the polarizing plate 9. This linearly polarized light is incident on the reflecting portion λ / 4 layer 7 to be circularly polarized light. Circularly polarized light reaches the reflective electrode 3 and is reflected by the liquid crystal layer 10 while maintaining almost the polarization state thereof. The reflected circularly polarized light is circularly polarized light whose rotational direction is reversed, and is again incident on the reflection part λ / 4 layer 7 through the liquid crystal layer 10 and converted into linearly polarized light orthogonal to the transmission axis of the polarizing plate 9, Absorbed by the polarizing plate 9.

  In the transmission part, the light irradiated from the rear surface by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. The linearly polarized light reaches the polarizing plate 9 while maintaining almost the polarization state in the liquid crystal layer 10 and the transmission portion λ / 4 layer 55 and is absorbed by the polarizing plate 9.

  As described above, in the liquid crystal display device 51, the slow axis of the transmission part λ / 4 layer 55 coincides with the transmission axis of the polarizing plate 9, so that the transmission part λ / 4 layer 55 does not function as a retardation layer. For this reason, in the reflection part, the reflection part λ / 4 layer 7 functions to obtain a sufficient reflectance, and in the transmission part, a new retardation layer for compensating the retardation of the retardation layer on the display surface side is provided. Transparent display can be realized without adding to the rear surface. Therefore, while achieving good display quality with high contrast in both reflective display and transmissive display, the retardation layer on the rear surface is no longer required, making the cell thinner and reducing the cost of the unnecessary retardation layer. Is done.

  In the above description, when a voltage is applied to the liquid crystal display device, the liquid crystal molecules of the liquid crystal layer are aligned substantially perpendicular to the substrate surface, and when no voltage is applied, the phase difference of λ / 4 and Although the configuration having a phase difference of λ / 2 at the transmission part has been described as an example, the liquid crystal display device of the present invention may be reversed. That is, it may be a liquid crystal layer having a phase difference of λ / 4 at the reflection portion and a phase difference of λ / 2 at the transmission portion when a voltage is applied to the liquid crystal display device.

  By the way, in the present embodiment, the retardation layer is not limited to the case where the retardation layer is composed of one layer of the reflection portion λ / 4 layer 7 and the transmission portion λ / 4 layer 55, but has a configuration composed of two layers as shown in FIG. There may be. In FIG. 15, the same components as those of the liquid crystal display device 51 of FIG. 12 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the liquid crystal display device 61 of this application example, the wavelength dispersion of the reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55 and the reflection part λ / 4 layer 7 as retardation layers is provided on the liquid crystal layer 10 side of the substrate 6. The reflective portion λ / 2 layer 22 and the transmissive portion λ / 2 layer 62 to be compensated are provided, and the slow axis of the retardation layer is different between the reflective portion and the transmissive portion. That is, the reflection part λ / 2 layer 62 and the reflection part λ / 4 layer 7 function as a λ / 2 layer and a λ / 4 layer, respectively, while the transmission part λ / 2 layer 62 and the transmission part λ / 4 layer. 55 has a slow axis coincident with, for example, the transmission axis of the polarizing plate 9 and does not function as a retardation layer. The two-layer retardation layer is formed by, for example, applying a liquid crystal polymer or an ultraviolet curable liquid crystal monomer having a nematic phase on an alignment film 54 that is aligned and divided into a reflective portion and a transmissive portion on the substrate 6. A λ / 2 layer 22 and a transmissive portion λ / 2 layer 62 are formed, and an alignment film 63 is formed on the λ / 2 layer by dividing the alignment between the reflective portion and the transmissive portion, and has a liquid crystal polymer or nematic phase. It is obtained by applying an ultraviolet curable liquid crystal monomer to form the reflection portion λ / 4 layer 7 and the transmission portion λ / 4 layer 55. Of course, it is also possible to divide the alignment by optical alignment treatment.

  In addition to the effect of the liquid crystal display device 51 which is the basic structure of the present embodiment, the retardation layer has the above-described two-layer structure, and the slow axis is made different between the reflective portion and the transmissive portion. The display device 61 can eliminate light leakage due to wavelength dispersion in a wide band when performing dark display, and can realize better image display.

  The present invention is not limited to a liquid crystal display device having a configuration in which a retardation layer is formed on the substrate 6 on the display surface side, but a liquid crystal having a configuration in which the retardation layer is formed on the substrate 2 on the backlight side. Of course, this also applies to a display device. That is, in the liquid crystal display device 71 shown in FIG. 16, the reflective electrode 3 and the transparent electrode 4 are formed on the rear substrate 2 side, and further the reflective portion λ / 4 which is a retardation layer via the alignment film 54 thereon. The layer 7 and the transmission part λ / 4 layer 55 are included. The reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55 are formed in the same manner as described with reference to FIG.

  In this case, a transparent electrode (not shown) is provided between the reflecting portion λ / 4 layer 7 and the transmitting portion λ / 4 layer 55 and the alignment film 53 for driving the liquid crystal to ensure driving of the liquid crystal. May be. However, when such a transparent electrode is provided, a plug 16 for connecting the transparent electrode to the TFT is provided. In this case, it is not necessary to provide the transparent electrode 4 between the substrate 2 and the transmission portion λ / 4 layer 55.

  Here, the reflection part λ / 4 layer 7 functions as a retardation layer, but the transmission part λ / 4 layer 55 has a slow axis that coincides with, for example, the transmission axis of the polarizing plate 9 and does not function as a retardation layer. . When the retardation layer is formed on the substrate on the backlight side as in the liquid crystal display device 71 shown in FIG. 16, the reflecting portion λ / 4 layer 7 functions in the reflecting portion to obtain sufficient reflectance. In the transmissive portion, transmissive display can be realized without adding a retardation layer on the display surface side to compensate for the retardation of the retardation layer on the rear surface. Therefore, as with the liquid crystal display device described so far, while achieving good display quality with high contrast in both reflective display and transmissive display, the retardation layer on the rear surface is not required, and the thickness and thickness of the cell are not required. Cost reduction equivalent to the retardation layer is achieved.

  Further, the liquid crystal display device of this embodiment can also be applied to a full-color liquid crystal display device 81 as shown in FIG.

  The liquid crystal display device 81 includes color filters 42R, 42G, and 42B corresponding to the red, green, and blue dots on the liquid crystal layer 10 side of the substrate 6, and the color filters 42R, 42G, and 42B are disposed on the color filters 42R, 42G, and 42B. As the phase difference layer, the reflection part λ / 4 layer 7R and the transmission part λ / 4 layer 55R, the reflection part λ / 4 layer 7G and the transmission part λ / 4 layer 55G, and the reflection part λ / 4 layer 7B and the transmission part λ / 4 Each of the layers 55B is formed, and the counter electrode 8 is formed on these retardation layers via the overcoat layer 43.

  The reflection layer λ / 4 layer 7R and the transmission unit λ / 4 layer 55R, the reflection unit λ / 4 layer 7G, the transmission unit λ / 4 layer 55G, and the reflection unit λ / 4 layer 7B, which are retardation layers, and the transmission layer The part λ / 4 layer 55B has a slow axis different between the reflection part and the transmission part so that the retardation layer of the transmission part does not function. As a result, similarly to the liquid crystal display device of the above-described example, the rear retardation layer for compensating the retardation of the retardation layer used for reflective display becomes unnecessary, and the number of used retardation layers can be reduced.

  Further, in the liquid crystal display device 81 of this application example, the reflection part λ / 4 layer 7R and the transmission part λ / 4 layer 55R, which are retardation layers, are formed in accordance with the transmission wavelengths of the color filters 42R, 42G, and 42B. By changing the film thicknesses of the λ / 4 layer 7G and the transmissive part λ / 4 layer 55G, and the reflective part λ / 4 layer 7B and the transmissive part λ / 4 layer 55B, the retardation layer of each part has a position of λ / 4. It shall have a phase difference. Thereby, it is possible to suppress the influence of wavelength dispersion of each color and realize a better image display.

  In the present invention, the transmission axis of the polarizing plate disposed on the front or rear surface and the slow axis of the retardation layer of the transmission part are completely orthogonal or parallel, and the retardation layer of the transmission part does not function at all. However, the slow axis of the transmission part may be slightly shifted. For example, the slow axis of the retardation layer of the transmissive portion may have a retardation determined in consideration of various characteristics of the liquid crystal layer. In this case, the slow axis of the retardation layer of the transmissive portion may be It is preferable that the shift gives the transmission part a phase difference that cancels out the residual phase difference layer of the liquid crystal layer when a sufficient voltage is applied to the liquid crystal layer. Thereby, compared with the case where the retardation layer of the transmissive part does not function at all, the dark display in the transmissive part is made darker, and a better image display can be realized.

  In the third embodiment, the slow axis of the retardation layer of the transmission part is exemplified as a configuration in which the transmission axis of the polarizing plate on the front surface coincides, but the slow axis of the retardation layer of the transmission part is Even if the configuration coincides with the transmission axis of the polarizing plate on the rear surface, the effect of the present invention can be obtained.

<Fourth embodiment>
Next, a fourth embodiment of a transflective liquid crystal display device to which the present invention is applied will be described. The liquid crystal display device of the fourth embodiment is a combination of the second embodiment and the third embodiment described above, and the basic configuration thereof will be described with reference to FIG. FIG. 18 shows an optical configuration of the reflection unit and the transmission unit together with a schematic cross-sectional view of a main part of the liquid crystal display device. The configuration is the same as the liquid crystal display device 51 of FIG. 12 described in the third embodiment. Further, the same components as those of the liquid crystal display device of FIG. 7 described in the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  That is, the liquid crystal display device 51 ′ shown in FIG. 18 is different from the liquid crystal display device described with reference to FIG. 12 in the third embodiment described above in the alignment direction of the liquid crystal layer between the reflective portion and the transmissive portion ( (Liquid crystal orientation) is adjusted in the same manner as described in the second embodiment, and other configurations are the same as those in the third embodiment.

  That is, in the liquid crystal display device 51 ′ shown in FIG. 18, the liquid crystal alignment of the reflecting portion is parallel to the substrate 2 and the substrate 6 and the polarizing plate 9 and the polarized light without applying a voltage to the reflecting portion liquid crystal layer 10 ′. The angle is set to 45 ° with respect to the transmission axis of the plate 5. In this state, the liquid crystal layer 10 ′ of the reflecting portion is adjusted to have a phase difference of λ / 4 when light passes through the liquid crystal layer 10 ′ once.

  On the other hand, in the transmissive portion, the liquid crystal alignment on the substrate 6 side is parallel to the transmission axis of the polarizing plate 9 and the liquid crystal alignment on the substrate 2 side is By being parallel, it is set to be twisted nematic that can be twisted by 90 °.

  Further, in a state where a voltage is applied to the liquid crystal layer 10 ′, the liquid crystal molecules are aligned substantially perpendicular to the surfaces of the substrates 2 and 6 in both the reflection part and the transmission part.

  Further, in the liquid crystal display device 51 ′, as described with reference to FIG. 12 in the third embodiment, an interlayer film 52 is provided in the reflection portion, and the transmission portion is also provided on the substrate 6 side of the transmission portion. A λ / 4 layer 55 is provided.

  Here, the interlayer film 52 provided in the reflective portion has a phase difference of λ / 4 in a state in which no voltage is applied to the liquid crystal layer 10 ′, and the liquid crystal molecules in the transmissive portion. Is provided with a film thickness that adjusts the cell gap (thickness of the liquid crystal layer 10 ') between the transmissive part and the reflective part so that the Morgan condition can be satisfied and the optical rotation can be maintained at an interval where the twisted nematic is sufficiently twisted by 90 ° It is done. Therefore, if the above-described conditions can be satisfied without the interlayer film 52, the interlayer film 52 need not be provided in the liquid crystal display device 51 '.

  Further, the transmissive part λ / 4 layer 55 provided on the substrate 6 side of the transmissive part has the slow axis coincident with the transmission axis of the polarizing plate 9 on the front surface, as described in the third embodiment. Thus, there is no effective phase difference. With such a configuration, transmissive display is realized without adding a rear retardation layer in order to compensate for the retardation of the reflection portion λ / 4 layer 7. In addition, the direction of the slow axis of the transmission portion λ / 4 layer 55 is configured such that there is no effective retardation of the retardation layer of the transmission portion, and the transmission axis or absorption of the polarizing plate on the display surface side. It may coincide with either the axis or the transmission axis or absorption axis of the polarizing plate on the rear surface.

  A case where an image is actually displayed on the above-described liquid crystal display device 51 ′ shown in FIG. 18 will be described with reference to FIGS. 19 and 20. In addition, in order to simplify description, illustration of the board | substrate 2, the counter electrode 8, and each alignment film is abbreviate | omitted in FIG.19 and FIG.20.

  First, a case where a voltage is not applied to the liquid crystal layer 10 ′ and a bright display is performed will be described with reference to FIG. 19.

  In the reflection part, the ambient light incident from the display surface becomes linearly polarized light that matches the transmission axis of the polarizing plate 9. The linearly polarized light is incident on the reflection portion λ / 4 layer 7 to be circularly polarized light, and is further converted to linearly polarized light by the liquid crystal layer 10 ′ and reaches the reflective electrode 3. The linearly polarized light whose traveling direction is reversed by the reflective electrode 3 passes through the liquid crystal layer 10 ′ again to become circularly polarized light, and this circularly polarized light passes through the reflection part λ / 4 layer 7 again and passes through the transmission axis of the polarizing plate 9. It becomes parallel linearly polarized light and passes through the polarizing plate 9.

  In the transmissive portion, the light emitted from the substrate 2 side (rear surface) by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. By the liquid crystal layer 10 ′ that is twisted nematic twisted by 90 °, the linearly polarized light becomes linearly polarized light orthogonal to the transmission axis of the polarizing plate 5, that is, linearly polarized light parallel to the transmission axis of the polarizing plate 9, and the transmission portion λ / The four layers 55 pass through the polarizing plate 9 while maintaining almost the polarization state.

  Next, a case where a voltage is applied to the liquid crystal layer 10 ′ for dark display will be described with reference to FIG. 20.

  In the reflection part, the ambient light incident from the display surface becomes linearly polarized light that matches the transmission axis of the polarizing plate 9. This linearly polarized light is incident on the reflecting portion λ / 4 layer 7 to be circularly polarized light. Circularly polarized light reaches the reflective electrode 3 and is reflected by the liquid crystal layer 10 ′ while maintaining almost the polarization state. The reflected circularly polarized light is circularly polarized light whose rotational direction is reversed, and is again incident on the reflection part λ / 4 layer 7 through the liquid crystal layer 10 and converted into linearly polarized light orthogonal to the transmission axis of the polarizing plate 9, Absorbed by the polarizing plate 9.

  In the transmission part, the light irradiated from the rear surface by the backlight becomes linearly polarized light that coincides with the transmission axis of the polarizing plate 5. The linearly polarized light reaches the polarizing plate 9 and is absorbed by the polarizing plate 9 while almost maintaining the polarization state in the liquid crystal layer 10 ′ and the transmission portion λ / 4 layer 55.

  As described above, the liquid crystal display device 51 ′ having such a configuration is provided with the reflection portion λ / 4 necessary for dark display of the reflection portion only in the reflection portion, similarly to the liquid crystal display device 51 of FIG. By providing the transmission part λ / 4 layer 55 whose slow axis coincides with the transmission axis of the polarizing plate 9 in the part, the same effect as that of the third embodiment can be obtained. In addition, since the liquid crystal alignment of the transmissive part is twisted nematic twisted by 90 °, display in the optical rotation mode is performed in the transmissive part, and display with better contrast can be performed. .

  In the above description, when a voltage is applied to the liquid crystal display device, the liquid crystal molecules of the liquid crystal layer are aligned substantially perpendicular to the substrate surface, and when no voltage is applied, the phase difference of λ / 4 and An example of a configuration that is twisted nematic twisted by 90 ° at the transmission portion is given as an example, but the liquid crystal display device of the present invention may be reversed. In other words, the liquid crystal layer may be a twisted nematic liquid crystal layer that is twisted by 90 ° in the phase difference of λ / 4 at the reflection portion and 90 ° at the transmission portion when a voltage is applied to the liquid crystal display device.

  By the way, in the present embodiment, the retardation layer is not limited to the case where the retardation layer is composed of one layer of the reflection portion λ / 4 layer 7 and the transmission portion λ / 4 layer 55, but has a configuration composed of two layers as shown in FIG. There may be. In FIG. 21, the same components as those of the liquid crystal display device 51 'of FIG. 18 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The liquid crystal display device 61 ′ of this application example has a wavelength of the reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55 and the reflection part λ / 4 layer 7 as retardation layers on the liquid crystal layer 10 ′ side of the substrate 6. The reflection part λ / 2 layer 22 and the transmission part λ / 2 layer 62 that compensate for dispersion are provided, and the slow axis of the retardation layer is different between the reflection part and the transmission part. In other words, the reflection part λ / 2 layer 22 and the reflection part λ / 4 layer 7 keep their slow axes at 60 ° and delay so that the λ / 4 layer of the optical band is configured by combining them. It is assumed that the phase axis is maintained at an angle of 15 ° with respect to the transmission axes of the polarizing plates 5 and 9. On the other hand, the slow axis of the transmission part λ / 2 layer 62 and the transmission part λ / 4 layer 55 coincides with, for example, the transmission axis of the polarizing plate 9 and does not function as a retardation layer.

  The two-layer retardation layer can be obtained in the same manner as described in the third embodiment.

  Further, in this case, the liquid crystal alignment of the reflecting portion is 0 ° or 90 ° parallel to the substrate 2 and the substrate 6 and 0 ° or 90 ° to the reflecting portion λ / 4 layer 7 in a state where no voltage is applied to the liquid crystal layer 10 ′. It is assumed that it is set to make an angle of. However, this is for adjusting the residual retardation, and the orientation direction may be any direction as long as the residual retardation is negligible. In this state, the liquid crystal layer 10 ′ of the reflecting portion is adjusted to have a phase difference of λ / 4 when light passes through the liquid crystal layer 10 ′ once. The liquid crystal alignment in the transmission part is the same as that of the liquid crystal display device 51 ′ in FIG. 18.

  As described above, the liquid crystal display device 61 ′ having the two-layer structure of the retardation layer and having the slow axis different between the reflection part and the transmission part has the basic structure of the present embodiment. In addition to the effect of the liquid crystal display device 51 ′, light leakage due to wavelength dispersion can be eliminated over a wide band, particularly when dark display is performed in the reflection portion, and a better image display can be realized.

  Note that the present embodiment is not limited to the liquid crystal display device in which the retardation layer is formed on the substrate 6 on the display surface side. The liquid crystal described in the third embodiment with reference to FIG. Of course, the present invention is also applicable to a liquid crystal display device having a structure in which a retardation layer is formed on the substrate 2 on the backlight side, similarly to the display device 71. That is, in the liquid crystal display device 71 ′ shown in FIG. 22, the reflective electrode 3 and the transparent electrode 4 are formed on the rear substrate 2 side, and the reflective portion λ / that is a retardation layer is further formed thereon via the alignment film 54. It has four layers 7 and a transmission part λ / 4 layer 55. The reflection part λ / 4 layer 7 and the transmission part λ / 4 layer 55 are formed in the same manner as described with reference to FIG.

  In this case, a transparent electrode (not shown) is provided between the reflecting portion λ / 4 layer 7 and the transmitting portion λ / 4 layer 55 and the alignment film 53 for driving the liquid crystal to ensure driving of the liquid crystal. This may be the same as described with reference to FIG.

  Here, the reflection part λ / 4 layer 7 functions as a retardation layer, but the transmission part λ / 4 layer 55 has a slow axis that coincides with, for example, the transmission axis of the polarizing plate 9 and does not function as a retardation layer. . When the retardation layer is formed on the substrate on the backlight side as in the liquid crystal display device 71 ′ shown in FIG. 22, the reflecting portion λ / 4 layer 7 functions in the reflecting portion to obtain a sufficient reflectance. At the same time, transmissive display can be realized without adding a retardation layer on the display surface side to compensate for the retardation of the retardation layer on the rear surface. Therefore, as with the liquid crystal display device described so far, while achieving good display quality with high contrast in both reflective display and transmissive display, the retardation layer on the rear surface is not required, and the thickness and thickness of the cell are not required. Cost reduction equivalent to the retardation layer is achieved.

  In addition, the liquid crystal display device of this embodiment can be applied to a full-color liquid crystal display device, similarly to the liquid crystal display device described with reference to FIG. 17 in the third embodiment.

  That is, the liquid crystal display device 81 ′ shown in FIG. 23 includes color filters 42R, 42G, and 42B corresponding to the red, green, and blue dots on the liquid crystal layer 10 ′ side of the substrate 6, and these color filters 42R, On 42G and 42B, as a phase difference layer, the reflection part λ / 4 layer 7R and the transmission part λ / 4 layer 55R, the reflection part λ / 4 layer 7G and the transmission part λ / 4 layer 55G, and the reflection part λ / 4 layer 7B and the transmission portion λ / 4 layer 55B are formed, and the counter electrode 8 is formed on the retardation layer via the overcoat layer 43.

  The reflection layer λ / 4 layer 7R and the transmission unit λ / 4 layer 55R, the reflection unit λ / 4 layer 7G, the transmission unit λ / 4 layer 55G, and the reflection unit λ / 4 layer 7B, which are retardation layers, and the transmission layer The part λ / 4 layer 55B has a slow axis different between the reflection part and the transmission part so that the retardation layer of the transmission part does not function. As a result, similarly to the liquid crystal display device of the above-described example, the rear retardation layer for compensating the retardation of the retardation layer used for reflective display becomes unnecessary, and the number of used retardation layers can be reduced.

  Further, in the liquid crystal display device 81 ′ of this application example, the reflection part λ / 4 layer 7R and the transmission part λ / 4 layer 55R, which are retardation layers, are formed in accordance with the transmission wavelengths of the color filters 42R, 42G, and 42B. By changing the film thickness of the part λ / 4 layer 7G and the transmission part λ / 4 layer 55G, and the reflection part λ / 4 layer 7B and the transmission part λ / 4 layer 55B, the retardation layer of each part is λ / 4. It shall have a phase difference. Thereby, it is possible to suppress the influence of wavelength dispersion of each color and realize a better image display.

  In the fourth embodiment, the present invention is not limited to the case where only the liquid crystal layer 10 ′ in the transmissive part is twisted nematic, and the liquid crystal layer 10 ′ in the reflective part may be twisted nematic. A case where the liquid crystal layer 10 ′ of the reflection part is also twisted nematic will be described with reference to FIG. 24. In FIG. 24, the same components as those of the liquid crystal display device 61 'of FIG. 21 are denoted by the same reference numerals, and detailed description thereof is omitted.

  The liquid crystal display device 61a of this application example is different from the liquid crystal display device 61 'described with reference to FIG. 21 in the liquid crystal alignment of the reflection portion, and the other configurations are the same.

  That is, in the liquid crystal display device 61a shown in FIG. 24, the liquid crystal alignment of the reflection portion is set to be twist alignment in a state where no voltage is applied to the liquid crystal layer 10 '. For this reason, in the liquid crystal display device 61a, the alignment film (not shown) on the surface facing the liquid crystal layer 10 ′ between the substrate 2 and the substrate 6 forms a predetermined angle between the substrate 2 side and the substrate 6 side. It is assumed that the orientation process has been performed. This angle is a balance between the size of the cell gap and the birefringence of the liquid crystal layer 10 ′. When no voltage is applied to the liquid crystal layer 10 ′, light passes through the liquid crystal layer 10 ′ once. It is adjusted to have a phase difference of / 4.

  Therefore, for example, as shown in FIG. 25, the liquid crystal alignment on the substrate 2 side and the liquid crystal alignment on the substrate 6 side may form an angle of 90 °. In this case, the alignment film facing the liquid crystal layer 10 ′ can be aligned in the same direction in the reflection part and the transmission part, and the labor of divided alignment can be saved.

  In the liquid crystal display device 61a of FIGS. 24 and 25, the liquid crystal molecules are aligned substantially perpendicular to the surfaces of the substrates 2 and 6 when a voltage is applied to the liquid crystal layer 10 ′. It is the same.

  Thus, the effective phase difference of the liquid crystal layer of the reflective portion is reduced by setting the liquid crystal alignment of the reflective portion to twisted nematic. For this reason, the cell gap for setting the reflection part to have a phase difference of λ / 4 widens, and the margin for the cell gap is expanded. As a result, it becomes possible to improve the yield of the liquid crystal display device.

  In the invention of the fourth embodiment described above, the transmission axis of the polarizing plate disposed on the front surface or the rear surface and the slow axis of the retardation layer of the transmission part are completely orthogonal or parallel, It is not limited to the case where the retardation layer of the part does not function at all, and the slow axis of the transmission part may be slightly shifted. For example, the slow axis of the retardation layer of the transmissive portion may have a retardation determined in consideration of various characteristics of the liquid crystal layer. In this case, the slow axis of the retardation layer of the transmissive portion may be It is preferable that the shift gives the transmission part a phase difference that cancels out the residual phase difference layer of the liquid crystal layer when a sufficient voltage is applied to the liquid crystal layer. Thereby, compared with the case where the retardation layer of the transmissive part does not function at all, the dark display in the transmissive part is made darker, and a better image display can be realized.

  Further, in the fourth embodiment, the example in which the slow axis of the retardation layer of the transmission part matches the transmission axis of the polarizing plate on the front surface is given as an example, but the slow axis of the retardation layer of the transmission part is Even if the configuration coincides with the transmission axis of the polarizing plate on the rear surface, the effect of the present invention can be obtained.

  Moreover, each structure demonstrated in 2nd Embodiment can obtain the effect specific to the combined structure by combining each other.

  Hereinafter, specific examples to which the present invention is applied will be described based on experimental results. Examples 1 to 5 correspond to the first embodiment, Examples 6 to 8 correspond to the second embodiment, and Examples 9 to 13 correspond to the third embodiment. Example 14 to Example 19 correspond to the fourth embodiment.

<Example 1>
In Example 1, a full-color panel having the same optical configuration as that of the liquid crystal display device 1 shown in FIG. 1 was produced.

  First, a substrate on the rear side on which a thin film transistor (TFT) for actively driving the liquid crystal layer was formed. A method for manufacturing the TFT will be described with reference to FIGS.

As the substrate 2, borosilicate glass (Corning 7059) was used. First, a gate electrode 91 made of Mo, MoW or the like, a gate insulating film 92, and amorphous silicon are sequentially deposited and patterned on the substrate 2, and an amorphous silicon is annealed with an excimer laser to crystallize a semiconductor thin film 93 formed by crystallization. Formed. Further, impurities of P and B are introduced into regions on both sides of the gate electrode of the semiconductor thin film 93 to form n-channel and p-channel TFTs. A first interlayer insulating film 94 made of SiO ₂ was formed above the substrate 2 so as to cover the TFT.

  Next, the first interlayer insulating film 94 corresponding to the source and drain of the semiconductor thin film 93 is opened by, for example, etching, and the signal line 95 is formed by patterning into a predetermined shape. Al was used for the signal line 95.

  Next, a second interlayer insulating film 96 having both a function as a scattering layer causing scattering reflection and a function as an interlayer insulating film is formed above the substrate 2 so as to cover the TFT and the signal line 95. . The transparent electrode 4 was formed of ITO (Indium Tin Oxide) in the region corresponding to the transmission part of the second interlayer insulating film 96, and the reflection electrode 3 was formed of Ag in the region corresponding to the reflection part. As a result, the substrate on the backlight side shown in FIG. 26 is obtained.

  On the opposite substrate, a black matrix was formed using Cr, and then R, G, and B patterns were formed as color filters on the substrate. Next, polyimide was printed on the color filter and rubbed to form an alignment film.

On this alignment film, a UV curable liquid crystal monomer is applied by spin coating, and through a light exposure process and a development process, a reflective part λ / 4 layer is formed as a retardation layer only on the reflective part, The retardation layer was removed from the transmission part. As an ultraviolet curable liquid crystal monomer, RMM34 manufactured by Merck & Co. was used. Since this ultraviolet curable liquid crystal monomer material becomes insufficiently polymerized due to the presence of oxygen, the above treatment was performed in an N ₂ atmosphere. In addition, since the RMM 34 has a refractive index anisotropy Δn of 0.145, a retardation that falls within the range of about 135 nm to 140 nm can be obtained by spin coating so that the thickness of the retardation layer is 950 nm. I was able to. After forming the retardation layer, the counter electrode was formed by sputtering ITO.

  After this, a normal cell process is performed. That is, an alignment film was formed by further printing and rubbing polyimide on the counter electrode.

  Here, the rubbing direction on the side where the retardation layer was formed was the same as the alignment direction of the liquid crystal polymer of the retardation layer. In addition, the rubbing direction on the side where the TFT or the like was formed was the direction in which the cell configuration was anti-parallel.

  As described above, a cell is assembled according to a normal process using a substrate on which a TFT or the like is formed and a substrate on which a retardation layer or the like is formed, and has the same optical configuration as the liquid crystal display device shown in FIG. And the panel of the structure in which the color filter was formed was obtained. When this panel was turned on, it was confirmed that an image display with high contrast was realized.

<Example 2>
In Example 2, a full-color panel having the same optical configuration as that of the liquid crystal display device 21 shown in FIG. 4 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared.

  In addition, a color filter was formed on the opposing substrate by the same process as in Example 1, polyimide was printed on the color filter, and an alignment film was formed by rubbing.

  On this alignment film, an ultraviolet curable liquid crystal monomer was applied so as to satisfy the λ / 2 condition, and patterning was performed so that the retardation layer remained only in the reflection portion. Thereby, the reflection part λ / 2 layer was formed as the retardation layer.

  Next, polyimide was printed, and a rubbing treatment was performed so that the direction was inclined by 60 ° with respect to the previous rubbing direction. Thereafter, an ultraviolet curable liquid crystal monomer was applied so as to satisfy the λ / 4 condition, and patterning was performed so that the retardation layer remained only in the reflection portion. Thereby, the reflection part λ / 4 layer was formed as the retardation layer. After forming the retardation layer composed of the reflective part λ / 2 layer and the reflective part λ / 4 layer, the counter electrode was formed by sputtering ITO.

  After this, a normal cell process is performed. That is, an alignment film was formed by further printing and rubbing polyimide on the counter electrode. Here, the rubbing treatment was performed so that the alignment direction of the liquid crystal layer was intermediate between λ / 2 and λ / 4.

  As described above, a cell is assembled according to a normal process using a substrate on which a TFT or the like is formed and a substrate on which a retardation layer or the like is formed, and has the same optical configuration as the liquid crystal display device shown in FIG. And the panel of the structure in which the color filter was formed was obtained. When this panel was turned on, it was confirmed that an image display with high contrast was realized.

<Example 3>
In Example 3, a full-color panel having the same optical configuration as that of the liquid crystal display device 31 shown in FIG. 5 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared.

  In addition, a color filter was formed on the opposing substrate by the same process as in Example 1, polyimide was printed on the color filter, and an alignment film was formed by rubbing.

  Next, a retardation layer composed of the reflective portion λ / 2 layer and the reflective portion λ / 4 layer was formed only on the reflective portion by the same process as in Example 2 described above.

  Next, polyimide was printed and a rubbing process was performed so as to be in a direction inclined by 90 ° from an intermediate direction between the two retardation layers. Further, a transmissive portion retardation layer for canceling the residual retardation when a voltage was applied to the liquid crystal was formed only in the transmissive portion. This transmissive portion retardation layer has a retardation of 30 nm, which is equal to the residual retardation when a voltage is applied to the liquid crystal layer.

  After forming the retardation layer and the transmissive portion retardation layer in the reflecting portion, the counter electrode was formed by sputtering ITO.

  After this, a normal cell process is performed. That is, an alignment film was formed by further printing and rubbing polyimide on the counter electrode.

  A cell is assembled according to a normal process using the substrate 2 on which a TFT or the like is formed as described above and the substrate 6 on which a retardation layer or the like is formed, and has the same optical configuration as the liquid crystal display device shown in FIG. A panel having a configuration in which a color filter is formed is obtained. When this panel was turned on, it was confirmed that a black display exceeding the display quality of the panel of Example 1 was obtained when transmissive display was performed, and an image display with higher contrast was realized.

<Example 4>
In Example 4, a panel having the same optical configuration as that of the liquid crystal display device 41 shown in FIG. 6 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared.

  In addition, a color filter was formed on the opposing substrate by the same process as in Example 1, polyimide was printed on the color filter, and an alignment film was formed by rubbing.

  On this alignment film, a UV curable liquid crystal monomer is applied by spin coating, and through a light exposure process and a development process, a reflection part λ / 4 layer is formed as a retardation layer only on the reflection part. The retardation layer was removed from the transmission part.

  At this time, the film thickness of each phase difference layer was set according to the phase difference of each pixel. That is, the film thickness of G was set to 950 nm as in Example 1. For B, since Δn is about 0.155 according to the retardation of the color, a retardation layer was formed so as to have a film thickness of 730 nm. For R, the retardation layer is formed so that the film thickness is about 1200 nm because Δn is about 0.135 in accordance with the retardation of the color.

  After forming the retardation layer, the counter electrode was formed by sputtering ITO.

  After this, a normal cell process is performed. That is, an alignment film was formed by further printing and rubbing polyimide on the counter electrode.

  As described above, a cell is assembled according to a normal process using a substrate on which a TFT or the like is formed and a substrate on which a retardation layer or the like is formed, and has the same optical configuration as the liquid crystal display device shown in FIG. And the panel of the structure in which the color filter was formed was obtained. When this panel was turned on, it was confirmed that a black display exceeding the display quality of the panel of Example 1 was obtained and an image display with higher contrast was realized.

<Example 5>
In Example 5, a panel having a configuration in which a retardation layer was formed only on the reflective portion of the backlight-side substrate on which TFTs and the like were formed was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared. Further, a reflective portion λ / 4 layer was formed as a retardation layer on the reflective electrode. Further, an ITO electrode was formed by sputtering on this.

  Moreover, the counter electrode was formed on the opposing substrate by sputtering ITO, and the retardation layer was not formed. Further, polyimide was printed on the counter electrode and rubbed to form an alignment film.

  As described above, a cell was assembled according to a normal process using the substrate on which the TFT and the retardation layer were formed and the substrate on which the counter electrode was formed, to obtain a panel. When this panel was turned on, it was confirmed that an image display with high contrast equivalent to that of the panel of Example 1 was realized when transmissive display was performed.

<Example 6>
In Example 6, a full-color panel having the same optical configuration as that of the liquid crystal display device 1 ′ shown in FIG. 7 was produced.

  First, a substrate (TFT substrate) on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared. Then, polyimide is printed on the reflective electrode 3 and the transmissive electrode 4 of the TFT substrate, and mask rubbing is performed, so that the reflective portion is in the direction of the transmission axis of the polarizing plate 5 provided on the other surface side of the TFT substrate. In the transmission part, an alignment film in the rubbing direction parallel to the polarizing plate 5 was formed.

  In addition, the reflective portion λ / 4 layer 7 was formed on the opposing substrate (counter substrate) by the same process as in Example 1, and the counter electrode 8 was further formed. At this time, the reflective portion λ / 4 layer 7 is formed so that the slow axis thereof forms an angle of 45 ° with respect to the transmission axis of the polarizing plate 9 provided on the other surface side of the counter substrate. This was done by setting the rubbing direction of the film.

  Thereafter, polyimide is printed on the counter electrode 8 and mask rubbing is performed, so that the reflection part forms an angle of 90 ° with respect to the slow axis of the reflection part λ / 4 layer 7 while the transmission part is polarized. An alignment film in the rubbing direction parallel to the plate 9 was formed.

  As described above, a cell was assembled according to a normal process using the TFT substrate having the alignment film formed on the surface side and the counter substrate. At this time, the TFT substrate and the counter substrate are bonded to each other so that the alignment film on the TFT substrate side and the alignment film on the counter plate side are anti-parallel in the reflection part and twisted at 90 ° in the transmission part. A liquid crystal material having a phase difference of λ / 4 was formed in the reflection portion by injecting and sealing a liquid crystal material having a birefringence index Δn = 0.09 in between. Thereafter, the polarizing plate 5 was attached to the TFT substrate side so that the transmission axis direction coincided with the rubbing direction in the transmission portion of the alignment film provided on the TFT substrate. Further, a polarizing plate 9 was attached to the counter substrate side so that the transmission axis direction coincided with the rubbing direction in the transmission portion of the alignment film provided on the counter substrate.

  Thus, a panel having the same optical configuration as that of the liquid crystal display device 1 'shown in FIG. 7 and having a color filter formed thereon was obtained. When this panel was turned on, black display in the transmissive part was further sufficient than in Example 1, and a display with high contrast could be obtained.

<Example 7>
In Example 7, a full-color panel having the same optical configuration as that of the liquid crystal display device 21 ′ shown in FIG. 10 was produced.

  First, the TFT substrate shown in FIG. 26 was prepared by the same process as in Example 6, and an alignment film was formed on the reflective electrode 3 and the transmissive electrode 4. However, the alignment film of the reflection part is rubbed so as to form an angle of 75 ° with respect to the transmission axis direction of the polarizing plate 5 provided on the other surface side of the TFT substrate, and the reflection film of the transmission part The rubbing treatment was performed in parallel with the transmission axis of the polarizing plate.

  Further, the reflective portion λ / 2 layer 22 and the reflective portion λ / 4 layer 7 were formed on the opposing substrate (counter substrate) by the same process as in Example 2, and an alignment film was further formed via the counter electrode 8. . At this time, the reflective portion λ / 2 layer 22 is formed so that the slow axis thereof forms an angle of 15 ° with respect to the transmission axis of the polarizing plate 9 provided on the other surface side of the counter substrate. This was done by setting the rubbing direction of the film. In addition, the reflection part λ / 4 layer 7 is formed such that the slow axis thereof forms an angle of 60 ° with respect to the slow axis of the reflection part λ / 2 layer 22 and is 75 with respect to the transmission axis of the polarizing plate 9. The rubbing direction of the underlying alignment film was set so as to form an angle of °. Further, the alignment film is formed in the reflection portion at an angle of 90 ° with respect to the slow axis of the reflection portion λ / 4 layer 7 and at an angle of 15 ° with respect to the transmission axis of the polarizing plate 9 while being transmitted. The part was rubbed in a direction parallel to the polarizing plate 9.

  As described above, using the TFT substrate having the alignment film formed on the surface side and the counter substrate, the cell is assembled in the same manner as in Example 6, and has the same optical configuration as the liquid crystal display device 21 ′ shown in FIG. A panel having a structure in which a color filter was formed was obtained. When this panel was turned on, a black display was sufficient as compared with Example 6 and a display with high contrast could be obtained.

<Example 8>
In Example 8, a full-color panel having the same optical configuration as that of the liquid crystal display device 21a shown in FIG. 11 was produced.

  First, the TFT substrate shown in FIG. 26 was prepared by the same process as in Example 6, and an alignment film was formed on the reflective electrode 3 and the transmissive electrode 4. However, the alignment film of the reflective portion was rubbed so as to form an angle of 52.5 ° with respect to the transmission axis direction of the polarizing plate 5 provided on the other surface side of the TFT substrate.

  Further, the reflective portion λ / 2 layer 22 and the reflective portion λ / 4 layer 7 were formed on the opposing substrate (counter substrate) in the same manner as in Example 7, and an alignment film was further formed via the counter electrode 8. However, for the alignment film of the reflecting portion, an angle of 96.5 ° is formed with respect to the slow axis of the reflecting portion λ / 4 layer 7 and an angle of 7.5 ° with respect to the transmission axis of the polarizing plate 9. The rubbing process was performed in the direction of

  As described above, a cell was assembled according to a normal process using the TFT substrate having the alignment film formed on the surface side and the counter substrate. At this time, the alignment film on the TFT substrate side and the alignment film on the opposite plate side form an angle of 45 ° at the reflection part, and an angle of 90 ° at the transmission part, and the cell gap is 2.7 μm at the reflection part. The TFT substrate and the counter substrate are bonded to each other so that the transmission portion is 4.8 μm, and a liquid crystal material having a birefringence index Δn = 0.1 is injected therebetween and sealed, so that λ / A liquid crystal layer 10 ′ having a phase difference of 4 was formed. Thereafter, the polarizing plate 5 and the polarizing plate 9 were attached in the same manner as in Example 6. The residual phase difference when a voltage was applied was adjusted with the λ / 4 layer.

  Thus, a panel having the same optical configuration as the liquid crystal display device 21a shown in FIG. 11 and having a color filter formed thereon was obtained. When this panel was turned on, a black display was sufficient as compared with Example 6 and a display with high contrast could be obtained. In addition, since the cell gap was widened by using the liquid crystal alignment in the reflecting portion as the twist alignment, the margin for the gap was wider than that in Example 7, so that it was possible to produce with a high yield.

<Example 9>
In Example 9, a full-color panel having the same optical configuration as that of the liquid crystal display device 51 shown in FIG. 12 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared.

  On the opposite substrate, a black matrix was formed using Cr, and then R, G, and B patterns were formed as color filters on the substrate. Next, polyimide was printed on the color filter and rubbed to form an alignment film.

  In the rubbing process at this time, mask rubbing was performed. Mask rubbing is a method in which either a reflective portion or a transmissive portion is masked with a resist by photolithography and rubbing is performed in a predetermined direction, and then the other region is masked with a resist and rubbing is performed in a predetermined direction. . Note that the rubbing direction was inclined at 45 ° with respect to the transmission axis of the polarizing plate on the front surface in the reflection portion, and the rubbing direction was parallel to the transmission axis of the polarizing plate on the front surface in the transmission portion.

On this alignment film, an ultraviolet curable liquid crystal monomer was applied by spin coating, and an λ / 4 layer was formed as a retardation layer by an exposure process. Since the liquid crystal polymer is aligned along the rubbing direction of the underlying alignment film, it functions as a λ / 4 layer in the reflective part, but in the transmissive part it is effective because the slow axis is parallel to the transmission axis of the polarizing plate on the front surface. Phase difference does not occur. As an ultraviolet curable liquid crystal monomer, RMM34 manufactured by Merck & Co. was used. Since this ultraviolet curable liquid crystal monomer material becomes insufficiently polymerized due to the presence of oxygen, the above treatment was performed in an N ₂ atmosphere. In addition, since RMM34 has a Δn of 0.145, a retardation that falls within about 135 nm to 140 nm in the plane can be obtained by spin coating so that the thickness of the retardation layer is 950 nm. After forming the retardation layer, the counter electrode was formed by sputtering ITO.

  After this, a normal cell process is performed. That is, an alignment film was formed by further printing and rubbing polyimide on the counter electrode.

  Here, the rubbing direction on the side where the retardation layer was formed was the same as the alignment direction of the liquid crystal polymer of the retardation layer. In addition, the rubbing direction on the side where the TFT or the like was formed was the direction in which the cell configuration was anti-parallel.

  After injecting and sealing liquid crystal between the substrate on which the TFT or the like is formed and the substrate on which the retardation layer or the like is formed, the slow axis and the transmission axis of the retardation layer in the transmission part are parallel to each other. Further, by attaching a polarizing plate to the front surface, a panel having the same optical configuration as the liquid crystal display device shown in FIG. 12 and having a color filter formed was obtained. When this panel was turned on, it was confirmed that high-contrast image display was realized in both reflective display and transmissive display.

<Example 10>
In Example 10, a full-color panel having the same optical configuration as that of the liquid crystal display device 61 shown in FIG. 15 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared.

  On the opposite substrate, a black matrix was formed using Cr, and then R, G, and B patterns were formed as color filters on the substrate. Next, polyimide was printed on the color filter, and the alignment film was formed by mask rubbing in the same manner as in Example 10.

  On this alignment film, an ultraviolet curable liquid crystal monomer was applied by spin coating, and a λ / 2 layer was formed as a retardation layer through an exposure process. Since the UV curable liquid crystal monomer is aligned along the rubbing direction of the underlying alignment film, it functions as a λ / 2 layer in the reflective part, but in the transmissive part, the slow axis is parallel to the transmission axis of the front polarizing plate. Therefore, an effective phase difference does not occur.

  Next, polyimide is printed on the λ / 2 layer, and the rubbing process is performed so that the reflective portion is inclined by 60 ° with respect to the previous rubbing direction, and the transmission portion is directed to the transmission axis of the polarizing plate on the front surface. The alignment film was formed by performing a rubbing process so that the rubbing directions were parallel to each other.

  An ultraviolet curable liquid crystal monomer was applied on the alignment film, and a λ / 4 layer was formed as a retardation layer through an exposure process. Since the ultraviolet curable liquid crystal monomer is aligned along the rubbing direction of the underlying alignment film, it functions as a λ / 4 layer in the reflective part, but in the transmissive part, the slow axis is parallel to the transmission axis of the front polarizing plate. Therefore, an effective phase difference does not occur.

  Next, a counter electrode was formed by sputtering ITO on the λ / 4 layer.

  After this, a normal cell process is performed. That is, an alignment film was formed by further printing and rubbing polyimide on the counter electrode. Here, the rubbing treatment was performed so that the alignment direction of the liquid crystal layer was intermediate between λ / 2 and λ / 4.

  As described above, a cell was assembled according to a normal process using a substrate on which a TFT or the like was formed and a substrate on which a retardation layer or the like was formed, and polarizing plates were attached to both surfaces of the substrate. Here, the front polarizing plate was arranged so that the transmission axis of the front polarizing plate had an inclination of 15 ° with respect to the slow axis of the reflection part λ / 2 layer. Further, the rear polarizing plate was arranged such that its transmission axis forms an angle of 90 ° with the transmission axis of the front polarizing plate. Therefore, the transmission axis of the front polarizing plate is parallel to the slow axis of the transmission part λ / 2 layer.

  As described above, a panel having the same optical configuration as that of the liquid crystal display device shown in FIG. 15 and having a color filter formed thereon was obtained. When this panel was turned on, it was confirmed that high-contrast image display was realized in both reflective display and transmissive display.

<Example 11>
In Example 11, a panel having the same optical configuration as that of the liquid crystal display device 71 shown in FIG. 16 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared. Furthermore, a λ / 4 layer was formed as a retardation layer by applying an ultraviolet curable liquid crystal monomer on the reflective electrode and the transparent electrode. At this time, an orientation process is applied to the base so that the rubbing direction is different between the reflecting portion and the transmitting portion by mask rubbing so that only the retardation layer of the reflecting portion functions as a λ / 4 layer. Further, polyimide was printed on the retardation layer to form an alignment film.

  Moreover, the counter electrode was formed on the opposing substrate by sputtering ITO, and the retardation layer was not formed. Further, polyimide was printed on the counter electrode and rubbed to form an alignment film.

  As described above, a cell was assembled according to a normal process using the substrate on which the TFT and the retardation layer were formed and the substrate on which the counter electrode was formed, to obtain a panel. When this panel was turned on, it was confirmed that an image display with a high contrast equivalent to that in Example 9 was realized when transmissive display was performed.

<Example 12>
In Example 12, a liquid crystal display device having the same optical configuration as that of the liquid crystal display device 81 shown in FIG. 17 was produced.

  First, a substrate on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared.

  Also, after forming a black matrix using Cr on the front substrate, R, G, and B patterns were formed as color filters on the substrate. Next, polyimide was printed on the color filter, and mask alignment was performed in the same manner as in Example 9 to form an alignment film.

  On this alignment film, an ultraviolet curable liquid crystal monomer was applied and subjected to an exposure process, whereby a λ / 4 layer was formed as a retardation layer. At this time, the film thickness of each phase difference layer was set according to the phase difference of each pixel. That is, G was set to a film thickness of 950 nm as in Example 9. For B, since Δn is about 0.155 in accordance with the retardation of the color, a retardation layer was formed so as to have a film thickness of 730 nm. For R, the retardation layer is formed so that the film thickness is about 1200 nm because Δn is about 0.135 in accordance with the retardation of the color.

  Since the ultraviolet curable liquid crystal monomer is aligned along the rubbing direction of the underlying alignment film, it functions as a λ / 4 layer in the reflective part, but in the transmissive part, the slow axis is parallel to the transmission axis of the front polarizing plate. Therefore, an effective phase difference does not occur.

  After forming the retardation layer, the counter electrode was formed by sputtering ITO.

  A panel having the same optical configuration as that of the liquid crystal display device shown in FIG. 17 is obtained by assembling a cell according to a normal process using the substrate on which the TFT or the like is formed as described above and the substrate on which the retardation layer or the like is formed. Got. When this panel was turned on, it was confirmed that a black display exceeding the display quality of the panel of Example 9 was obtained and an image display with higher contrast was realized.

<Example 13>
In Example 13, a full-color panel was produced in the same manner as in Example 10 except that the photo-alignment treatment was adopted to divide the retardation layer. The alignment film used was manufactured by Bantico.

  When this panel was turned on, as in Example 10, it was confirmed that high-contrast image display was realized in both reflective display and transmissive display.

<Example 14>
In Example 14, a full-color panel having the same optical configuration as that of the liquid crystal display device 51 ′ shown in FIG. 18 was produced.

  First, a substrate (TFT substrate) on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared. However, in the formation of this TFT substrate, an interlayer film 52 having a thickness corresponding to the difference between the cell gaps of the reflective portion and the transmissive portion was provided below the reflective electrode 3.

  Thereafter, polyimide is printed on the reflective electrode 3 and the transmissive electrode 4 of the TFT substrate, and mask rubbing is performed, so that the reflective portion is in the direction of the transmission axis of the polarizing plate 5 provided on the other surface side of the TFT substrate. While forming an angle of 45 °, an alignment film 53 in the rubbing direction parallel to the polarizing plate 5 was formed in the transmission part.

  In addition, the reflective portion λ / 4 layer 7 and the transmissive portion λ / 4 layer 55 were formed on the opposing substrate (counter substrate) by the same process as in Example 9, and the counter electrode 8 was further formed. At this time, the slow axis of the reflection portion λ / 4 layer 7 forms 45 ° with the transmission axis of the polarizing plate 9 provided on the counter substrate, while the slow axis of the transmission portion λ / 4 layer 55 is the polarizing plate 9. So that it is parallel to the transmission axis.

  Thereafter, polyimide is printed on the counter electrode 8 and mask rubbing is performed, so that the reflection portion forms an angle of 90 ° with respect to the slow axis of the reflection portion λ / 4 layer 7, while the transmission portion An alignment film 56 in the rubbing direction parallel to the slow axis of the transmission portion λ / 4 layer 55 was formed.

  As described above, a cell was assembled according to a normal process using the TFT substrate having the alignment film formed on the surface side and the counter substrate. At this time, the alignment film 53 on the TFT substrate side and the alignment film 56 on the opposite plate side are anti-parallel at the reflection part, form an angle of 90 ° at the transmission part, and have a cell gap of 1.4 μm at the reflection part. The TFT substrate and the counter substrate are bonded to each other so as to have a thickness of 4.0 μm, and a liquid crystal material having a birefringence index Δn = 0.12 is injected between them and sealed, so that λ / 4 is formed in the reflective portion. A liquid crystal layer 10 ′ having a phase difference of 1 is formed. Thereafter, the polarizing plate 5 was attached to the TFT substrate side so that the transmission axis direction coincided with the rubbing direction in the transmission part of the alignment film 53. Further, the polarizing plate 9 was attached to the counter substrate side so that the transmission axis direction coincided with the rubbing direction in the transmission part of the alignment film 56. The residual phase difference when a voltage was applied was adjusted with the λ / 4 layer.

  Thus, a panel having the same optical configuration as the liquid crystal display device 51 'shown in FIG. 18 and having a color filter formed thereon was obtained. When this panel was turned on, a high-contrast display was realized for both the reflective display at the reflective portion and the transmissive display at the transmissive portion. In particular, with regard to transmissive display, it was possible to perform display with a higher contrast and a wider viewing angle than Example 9 (see FIG. 12).

  In Example 14, the TFT substrate and the counter substrate were bonded together so that the cell gap when assembling the cells was 1.8 μm at the reflection part and 4.8 μm at the transmission part. A panel in which a liquid crystal layer 10 ′ having a phase difference of λ / 4 is formed in the reflection portion by injecting and sealing a liquid crystal material having a refractive index Δn = 0.01, but the same effect can be obtained. I was able to. Also in this panel, the residual phase difference when a voltage was applied was adjusted by the λ / 4 layer.

<Example 15>
In Example 15, a full-color panel having the same optical configuration as that of the liquid crystal display device 61 ′ shown in FIG. 21 was produced.

  First, a substrate (TFT substrate) on which a TFT and the like and an interlayer film 52 as shown in FIG. 26 are formed by the same process as in Example 14 is prepared, and on the reflective electrode 3 and the transmissive electrode 4 of this TFT substrate. An alignment film 53 was formed. However, the alignment film 53 forms a rubbing of 15 ° with respect to the transmission axis direction of the polarizing plate 5 provided on the other surface side of the TFT substrate in the reflection portion, and parallel to the polarizing plate 5 in the transmission portion. Formed in the direction.

  Further, the reflective portion λ / 2 layer 22, the reflective portion λ / 4 layer 7, the transmissive portion λ / 2 layer 62, and the transmissive portion λ layer 55 are formed on the opposing substrate (opposed substrate) by the same process as in Example 10. Then, an alignment film 56 is formed via the counter electrode 8. At this time, the reflective portion λ / 2 layer 22 is formed so that the slow axis is at an angle of 75 ° with respect to the transmission axis of the polarizing plate 9 provided on the other surface side of the counter substrate. This was done by setting the rubbing direction of the film. The reflection part λ / 4 layer 7 is formed such that the slow axis thereof forms an angle of 60 ° with respect to the slow axis of the reflection part λ / 2 layer 22 and is 15 with respect to the transmission axis of the polarizing plate 9. The rubbing direction of the underlying alignment film was set so as to form an angle of °. On the other hand, in the formation of the transmissive part λ / 2 layer 62 and the transmissive part λ layer 55, the rubbing direction of the underlying alignment film is set so that the respective slow axes are parallel to the transmission axis of the polarizing plate 9. went. Further, the formation of the alignment film 56 forms an angle of 90 ° with respect to the slow axis of the reflective portion λ / 4 layer 7 and 75 ° with respect to the transmission axis of the polarizing plate 9 in the reflective portion. The part was rubbed in a direction parallel to the polarizing plate 9.

  As described above, using the TFT substrate having the alignment films 53 and 56 formed on the surface side and the counter substrate, a cell is assembled in the same manner as in Example 14 and has the same optical configuration as the liquid crystal display device 61 ′ shown in FIG. And the panel of the structure in which the color filter was formed was obtained. When this panel was turned on, a high-contrast display was realized for both the reflective display at the reflective portion and the transmissive display at the transmissive portion. In particular, with respect to reflective display, display with higher contrast than that of Example 14 can be performed, and with respect to transmissive display, similarly to Example 14, high contrast and a wide viewing angle are obtained.

<Example 16>
In Example 16, a full-color panel having the same optical configuration as that of the liquid crystal display device 71 ′ shown in FIG. 22 was produced. This panel has the same optical configuration as that of the panel of Example 14 described with reference to FIG. 18, and the floor of Example 14 is that a retardation layer is provided on the TFT substrate side.

  First, a substrate (TFT substrate) on which a TFT and the like and an interlayer film 52 as shown in FIG. 26 are formed by the same process as in Example 11 is prepared, and a reflective portion λ // is formed on the reflective electrode 3 of this TFT substrate. In addition to forming the four layers 7, the transmissive portion λ / 4 layer 55 was formed on the transmissive electrode 4, and the alignment film 53 was further formed. However, the alignment film 53 forms an angle of 45 ° with respect to the transmission axis direction of the polarizing plate 5 provided on the other surface side of the TFT substrate in the reflection portion, while parallel to the polarizing plate 5 in the transmission portion. The rubbing direction was formed.

  Further, on the opposing substrate (opposite substrate), an interlayer film 52 having a thickness corresponding to the difference between the cell gaps of the reflective portion and the transmissive portion is formed in the reflective portion by the same process as in Example 11, and then the counter electrode 8 is formed. Further, an alignment film 56 was formed. However, the alignment film 56 forms an angle of 45 ° with respect to the transmission axis direction of the polarizing plate 9 provided on the other surface side of the corresponding substrate at the reflection portion, and anti-parallel with the alignment film 53 on the TFT substrate side. On the other hand, in the transmission part, an alignment film in the rubbing direction parallel to the transmission axis direction of the polarizing plate 9 provided on the other surface side of the counter substrate was formed.

  A cell is assembled in the same manner as in Example 14 using the TFT substrate having the alignment films 53 and 56 formed on the surface side and the counter substrate as described above, and has the same optical configuration as the liquid crystal display device 71 ′ shown in FIG. And the panel of the structure in which the color filter was formed was obtained. When this panel was turned on, both high-contrast display as in Example 14 could be realized for both the reflective display at the reflective portion and the transmissive display at the transmissive portion.

<Example 17>
In Example 17, a full-color panel having the same optical configuration as that of the liquid crystal display device 81 ′ shown in FIG. 23 was produced.

  First, a substrate (TFT substrate) on which TFTs and the like as shown in FIG. 26 were formed by the same process as in Example 1 was prepared. However, in the formation of the TFT substrate shown in FIG.

  Thereafter, polyimide is printed on the reflective electrode 3 and the transmissive electrode 4 of the TFT substrate, and mask rubbing is performed, so that the reflective portion is in the direction of the transmission axis of the polarizing plate 5 provided on the other surface side of the TFT substrate. While forming an angle of 45 °, an alignment film 53 in the rubbing direction parallel to the polarizing plate 5 was formed in the transmission part.

  Further, R, G, and B color filters 42R, 42G, and 42B are formed on the opposing substrate (counter substrate) by the same process as in Example 12 (see FIG. 17), and each of the color filters is matched to the retardation of each color. The reflection part λ / 4 layers 7R, 7G, and 7B and the transmission part λ / 4 layers 55R, 55G, and 55B having the film thickness were formed, and the alignment film 56 was formed through the overcoat layer 43 and the counter electrode 8. At this time, the slow axis of the reflection part λ / 4 layers 7R, 7G, and 7B forms an angle of 45 ° with respect to the transmission axis direction of the polarizing plate 9 provided on the other surface side of the counter substrate. The slow axes of the λ / 4 layers 55R, 55G, and 55B were made parallel to the transmission axis of the polarizing plate 9. Further, the alignment film 56 forms an angle of 90 ° with respect to the slow axis of the reflection part λ / 4 layers 7R, 7G, and 7B in the reflection part, while the transmission part λ / 4 layers 55R and 55G in the transmission part. , 55B in a rubbing direction parallel to the slow axis. As for the optical axis and the rubbing direction, the optical configuration is the same as that of the panel of Example 14 described with reference to FIG. 18, and the thickness of the retardation layer is changed.

  As described above, a cell is assembled in the same manner as in Example 14 using the TFT substrate having the alignment films 53 and 56 formed on the surface side and the counter substrate, and has the same optical configuration as the liquid crystal display device 81 ′ shown in FIG. And the panel of the structure in which the color filter was formed was obtained. When this panel was turned on, both the reflective display at the reflective portion and the transmissive display at the transmissive portion were able to realize a display with sufficient black display and higher contrast than Example 14.

<Example 18>
In Example 18, a full-color panel was produced in the same manner as in Example 15 except that a photo-alignment process was employed in order to orientation-divide each retardation layer of the reflection part and the transmission part. In the photo-alignment treatment, the transmission portion and the reflection portion were separately polarized by mask exposure, and the reflection portion λ / 4 layer and the transmission portion λ · 4 layer were aligned in the same direction as in Example 18.

  When this panel was turned on, as in Example 15, it was confirmed that high-contrast image display was realized in both reflective display and transmissive display.

<Example 19>
In Example 19, a full-color panel having the same optical configuration as that of the liquid crystal display device 61a shown in FIG. 24 was produced.

  First, a substrate (TFT substrate) on which a TFT and the like and an interlayer film 52 as shown in FIG. 26 are formed by the same process as in Example 14 is prepared, and on the reflective electrode 3 and the transmissive electrode 4 of this TFT substrate. An alignment film 53 was formed. However, the alignment film 53 forms an angle of 37.5 ° with respect to the transmission axis direction of the polarizing plate 5 provided on the other surface side of the TFT substrate in the reflection portion, while the polarizing film 5 in the transmission portion. It was formed in a rubbing direction that was parallel.

Further, the reflective portion λ / 2 layer 22, the reflective portion λ / 4 layer 7, the transmissive portion λ / 2 layer 62, and the transmissive portion are formed on the opposing substrate (opposed substrate) by the same process as in Example 15 (see FIG. 21). A part λ / 4 layer 55 was formed, and an alignment film 56 was formed via the counter electrode 8.
However, the alignment film 56 is formed in the direction parallel to the polarizing plate 9 in the transmissive part, while forming an angle of 22.5 ° with respect to the slow axis of the reflective part λ / 4 layer 7 in the reflective part. A rubbing treatment was performed.

  A cell was assembled in the same manner as in Example 14 using the TFT substrate having the alignment films 53 and 56 formed on the front surface side and the counter substrate as described above. At this time, the rubbing directions of the alignment films 53 and 56 form an angle of 45 ° at the reflection portion and an angle of 90 ° at the transmission portion, and the cell gap becomes 2.7 μm at the reflection portion and 4.8 μm at the transmission portion. In this way, the TFT substrate and the counter substrate were bonded together, and a liquid crystal material having a birefringence Δn = 0.10 was injected between them and sealed. Thereafter, the polarizing plate 5 was attached to the TFT substrate side so that the transmission axis direction coincided with the rubbing direction in the transmission part of the alignment film 53. Further, the polarizing plate 9 was attached to the counter substrate side so that the transmission axis direction coincided with the rubbing direction in the transmission part of the alignment film 56.

  Thus, a panel having the same optical configuration as the liquid crystal display device 61a shown in FIG. 24 and having a color filter formed was obtained. When this panel was turned on, both the reflective display at the reflective portion and the transmissive display at the transmissive portion were able to realize a display with high contrast as in Example 15. In addition, since the liquid crystal alignment in the reflective portion was twisted nematic and the cell gap was widened, the margin for the gap was widened as compared with Example 15, so that it was possible to produce with a high yield.

  In Example 19, when assembling the cell, the alignment film 53 on the TFT substrate side and the alignment film 56 on the counter plate side form an angle of 90 ° in both the reflection part and the transmission part, and the cell gap is The TFT substrate and the counter substrate are bonded to each other so that the reflection portion is 3.3 μm and the transmission portion is 4.8 μm, and a liquid crystal material having a birefringence Δn = 0.10 is injected between them to seal. Thus, a full-color panel having the same optical configuration as that of the liquid crystal display device 61a shown in FIG. 25 was also produced, but the same effect could be obtained.

It is a principal part schematic sectional drawing which shows the liquid crystal display device of the structure used as the foundation of 1st Embodiment. It is a disassembled perspective view which shows the optical structure when not applying a voltage to the liquid crystal display device shown in FIG. It is a disassembled perspective view which shows the optical structure in the case of applying a voltage to the liquid crystal display device shown in FIG. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the application example of 1st Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the other application example of 1st Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the further another application example of 1st Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the structure used as the foundation of 2nd Embodiment. FIG. 8 is an exploded perspective view showing an optical configuration when no voltage is applied to the liquid crystal display device shown in FIG. 7. It is a disassembled perspective view which shows the optical structure in the case of applying a voltage to the liquid crystal display device shown in FIG. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the application example of 2nd Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the other application example of 2nd Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the structure used as the foundation of 3rd Embodiment. FIG. 13 is an exploded perspective view showing an optical configuration when no voltage is applied to the liquid crystal display device shown in FIG. 12. It is a disassembled perspective view which shows the optical structure in the case of applying a voltage to the liquid crystal display device shown in FIG. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the application example of 3rd Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the other application example of 3rd Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the further another application example of 3rd Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the structure used as the foundation of 4th Embodiment. FIG. 19 is an exploded perspective view showing an optical configuration when no voltage is applied to the liquid crystal display device shown in FIG. 18. It is a disassembled perspective view which shows the optical structure in the case of applying a voltage to the liquid crystal display device shown in FIG. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the application example of 4th Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the other application example of 4th Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the further another application example of 4th Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the further another application example of 4th Embodiment. It is a principal part schematic sectional drawing which shows the liquid crystal display device of the further another application example of 4th Embodiment. It is sectional drawing which shows the board | substrate of the back surface in which TFT was formed. It is a principal part schematic sectional drawing which shows the conventional transflective liquid crystal display device provided with two phase difference layers. It is a principal part schematic sectional drawing which shows the conventional semi-transmissive liquid crystal display device provided with four phase difference layers.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 2 ... Board | substrate, 3 ... Reflective electrode, 4 ... Transparent electrode, 5 ... Polarizing plate, 6 ... Board | substrate, 7 ... Reflection part (lambda) / 4 layer, 8 ... Counter electrode, 9 ... Polarizing plate, 10 ... Liquid crystal layer, 10 '... Liquid crystal layer

Claims (15)

A pair of substrates;
A liquid crystal layer sandwiched between the pair of substrates;
A liquid crystal display device comprising: a retardation layer provided on at least one of the substrates on the liquid crystal layer side and having a reflection portion having a larger retardation than a transmission portion. The liquid crystal display device according to claim 1, wherein the retardation layer is formed only in a portion corresponding to the reflective portion of the substrate. The liquid crystal display device according to claim 1, wherein the retardation layer of the reflecting portion is a λ / 4 layer. 4. The liquid crystal display device according to claim 1, wherein the retardation layer of the reflecting section includes two layers, a λ / 4 layer and a retardation layer that compensates for chromatic dispersion in the λ / 4 layer. 5. . The retardation layer of the reflecting portion is composed of two layers, a λ / 4 layer and a retardation layer that compensates for chromatic dispersion in the λ / 4 layer.
The liquid crystal display device according to claim 1, wherein the retardation layer that compensates for chromatic dispersion is a λ / 2 layer. The liquid crystal display device according to claim 1, wherein at least one of the substrates includes a color filter. At least one of the substrates includes a color filter,
The liquid crystal display device according to claim 1, wherein the retardation layer is adjusted to a film thickness that matches a transmission wavelength of the color filter. At least one of the substrates includes a color filter,
The liquid crystal display device according to claim 1, wherein the retardation layer has a phase difference of λ / 4 according to a transmission wavelength of the color filter. At least one of the substrates includes a color filter,
The liquid crystal display device according to claim 1, wherein the retardation layer and the color filter are provided on the same surface side of the substrate. At least one of the substrates includes a color filter,
The liquid crystal display device according to claim 1, wherein the retardation layer is formed on the color filter. The liquid crystal display device according to claim 1, wherein a polarizing plate is provided on a surface of the substrate opposite to the surface on which the retardation layer is formed. The liquid crystal display device according to claim 1, wherein the retardation layer is made of a liquid crystal polymer. The retardation layer is made of a liquid crystal polymer,
The liquid crystal display device according to claim 1, wherein the liquid crystal polymer is obtained by curing an ultraviolet curable liquid crystal monomer exhibiting a nematic phase. The liquid crystal display device according to claim 1, wherein the retardation layer has a slow axis different between the reflection portion and the transmission portion. The retardation layer has a slow axis different between the reflection part and the transmission part,
A polarizing plate is provided on the surface opposite to the surface on which the retardation layer of the substrate is formed,
The liquid crystal display device according to claim 1, wherein a slow axis of the retardation layer of the transmissive portion is in the same direction as a transmission axis or an absorption axis of the polarizing plate.

Images