JP4665388B2 - Liquid crystal device and electronic device - Google Patents

Description

  The present invention can be applied to a reflective or transflective liquid crystal display device to improve blurring and blurring of the display, and to obtain a clear display. The present invention relates to a technology capable of providing an electronic device including a possible liquid crystal device.

  In various electronic devices such as notebook personal computers, portable game machines, and electronic notebooks, liquid crystal display devices with low power consumption are often used as display units. Particularly in recent years, with the diversification of display contents, the demand for liquid crystal display devices capable of color display is increasing. In addition, in order to increase the battery driving time of the electronic device, a reflective color liquid crystal display device that does not require a backlight device has been developed.

  An outline of a configuration example of a conventional reflective color liquid crystal display device will be described below with reference to the drawings.

  18 (a) and 18 (b) are enlarged schematic cross-sectional views showing a main part of a conventional reflective color liquid crystal display device. Among these, FIG. 18A shows a front scattering plate type reflection type liquid crystal display device, and FIG. 18B shows an inner surface scattering reflection plate type liquid crystal display device.

  In the forward scattering plate type liquid crystal display device shown in FIG. 18A, a liquid crystal layer 102 is sandwiched between a pair of glass substrates 100 and 101, and one side (the upper side in the drawing) of the glass substrate 101 on the liquid crystal layer 102 side. A color filter 104 is provided on the surface portion, and a light reflecting layer 103 is provided on the surface portion on the liquid crystal layer 102 side of the other (lower side in the drawing) glass substrate 100. Further, on the upper surface side of the glass substrate 101, a forward scattering film 105 in which metal oxide particles are dispersed as a filler in a base material made of, for example, 50 to 200 μm thick triallyl cyanate is a transparent adhesive material or adhesive sheet ( The polarizing plate 106 is provided thereon.

  In such a forward scattering type reflective liquid crystal device, incident light L1 passes through the polarizing plate 106, the forward scattering film 105, the glass substrate 101, the liquid crystal layer 102, and the color filter 104, and then enters the light reflecting layer 103 that also serves as a drive electrode. The light reflected by the surface is emitted from the liquid crystal device through the liquid crystal layer 102, the color filter 104, the glass substrate 101, the forward scattering film 105, and the polarizing plate 106, and is visually recognized by the observer E as reflected light L2. . Here, the light emitted from the liquid crystal device is controlled by the state of the liquid crystal layer 102, that is, the polarization state of the reflected light is controlled by the alignment state of the liquid crystal molecules in the liquid crystal layer 102, and the polarization state of the reflected light is If it coincides with the polarization axis, it passes through the polarizing plate 106 and a desired color display is made.

  18B includes a pair of glass substrates 100 and 101 and a liquid crystal layer 102, and the surface of the glass substrate 100 on the liquid crystal layer 102 side also serves as a light reflection layer. A pixel electrode 107 made of an Al thin film or the like is formed in a state in which an uneven portion for irregularly reflecting light is provided on the surface.

  Here, a color filter 104 is formed on the surface of the glass substrate 101 on the light incident side on the liquid crystal layer 102 side, and a polarizing plate 106 is provided on the upper surface side of the glass substrate 101. In such an internal scattering plate type reflective liquid crystal display device, the incident light L1 passes through the polarizing plate 106, the glass substrate 101, the color filter 104, and the liquid crystal layer 102, and then the concave-convex light reflecting layer 107 that also serves as a pixel electrode. After the light is irregularly reflected on the surface of the liquid crystal layer and the polarization is changed depending on the state of the liquid crystal layer 102, the reflected light passes through the color filter 104, the glass substrate 101, and the polarizing plate 106, and is transmitted through the polarizing plate 106 depending on the polarization state of the reflected light. When the light is transmitted, it is visually recognized as a color display by entering the observer's naked eye E as scattered light L3 ′.

  By the way, in the conventional structure shown in FIG. 18A, the forward scattering film 105 weakens strong mirror reflection (regular reflection) in a specific direction unique to the mirror surface when the light reflection layer 103 is a mirror reflection layer. It is used for the purpose of enabling bright display in as wide a range as possible.

  This type of forward scattering film 105 is generally made of an acrylic resin layer (for example, refractive index n = 1.48 to 1.49) having a thickness of about 25 to 30 μm (25 to 30 × 10 −6 m). It has a structure in which a large number of beads (for example, refractive index n = 1.4) having a particle size of about 4 μm (4 × 10 −6 m) are dispersed therein. It is widely used in reflective liquid crystal display devices such as equipment.

  As a liquid crystal display device for a portable device, a transflective liquid crystal display device having a backlight in addition to the reflective type is also known. In this type of conventional transflective liquid crystal display device, the reflective layer is configured as a transflective layer, and in the case of transmissive display, the light from the backlight reaches the viewer side through the transflective layer. In a state where display is performed and a backlight is not used, the reflective liquid crystal display device is configured so that reflected light can be used effectively.

  However, the above-described forward scattering film 105 tends to be mixed before different information for each different pixel is recognized by the user's eyes, and display blur is likely to occur. Had. As shown in FIG. 18 (a), this is due to the scattering that occurs in the forward scattering film 105 from when the incident light is reflected by the reflective layer 103 until it reaches the eyes of the user. If white display and black display are performed with matching pixels, the boundary between the white display and the black display becomes difficult to understand due to the scattering action of the forward scattering film 105, and the display is blurred (blurred). The inventor believes that this is the case.

  When observing a liquid crystal panel, the observer usually observes the display from a direction deviating from the regular reflection direction of incident light, in other words, from a direction near the normal line or a direction closer to the normal direction than the regular reflection direction. When the reflective liquid crystal display device shown in FIG. 18A is observed from a direction deviated from the regular reflection direction, there is a region where the contrast is low, and there is a problem that it is difficult to see. This is because, in a conventional reflective liquid crystal display device, a region with high contrast is deviated from the direction near the normal line or the region viewed from the direction closer to the normal direction than the specular reflection direction, and thus there is a decrease in contrast. The inventor thinks.

  Further, when considering the blurring of the display of the liquid crystal device provided with the color filter 104, the boundary of the color display tends to be difficult to discriminate, and there is a risk of color mixing, so that good color development cannot be obtained. There is a fear.

    In addition, the situation that the display is blurred, the contrast is lowered, or sufficient color developability cannot be obtained also applies to the case where reflective display is performed in a transflective liquid crystal display device. It is.

  Next, in the configuration (inner surface scattering structure) provided with the light-reflective pixel electrode 107 provided with unevenness as shown in FIG. 18B, there is little possibility of causing the above-described display blur in the front scattering film. However, since a special processing step and man-hours are required to manufacture the pixel electrode 107 having unevenness, there is a problem that the manufacturing cost increases.

  From the background as described above, the present inventors have conducted further research focusing on the forward scattering film, and as a result, the scattering of the liquid crystal display device is blurred by providing directivity to the scattering property of the forward scattering film. It was found that (blur) can be eliminated, and the present invention was reached. Further, as a result of the inventors' research on the forward scattering film, in the case of the liquid crystal display device having the structure in which the forward scattering film 105 is arranged as shown in FIG. 18A, the incident light L1 is forwarded for the first time. Scattered light generated when passing through the scattering film 105 is less likely to greatly affect display blur (blur) and contrast reduction, but is diffused when reflected light passes through the forward scattering film 105 again. Is easily observed by the observer E, and it is known that the scattered light when the reflected light passes through the scattering film 105 has a great influence on the blur (blur) of the display.

  The present invention has been made in view of the above-described problems, and can improve display quality by improving display bleeding and contrast reduction, enabling clear display and providing an inner scattering plate. Another object is to provide a liquid crystal device that can be simplified in configuration with respect to the liquid crystal device provided and can reduce manufacturing costs while providing a clear display, and an electronic device including the liquid crystal device.

In order to solve the above problems, a liquid crystal device of the present invention includes a pair of substrates, a nematic liquid crystal layer having a twist angle θt sandwiched between the pair of substrates, and the one of the pair of substrates. A liquid crystal panel comprising: a reflective layer or a semi-transmissive reflective layer provided on the liquid crystal layer side; and a directional forward scattering film provided on the opposite side of the pair of substrates to the liquid crystal layer side. It is a liquid crystal device that performs reflection display by light incident on the directional forward scattering film from the outside, and the forward scattered light transmitted through the directional forward scattering film is ±± with respect to the traveling direction of incident light. The ratio of the light intensity of the forward scattered light traveling in the direction within 2 ° to the incident light intensity is defined as parallel light transmittance, and the forward scattered light diffuses beyond ± 2 ° with respect to the traveling direction of the incident light. Of the light intensity of the light to the incident light intensity The ratio is defined as diffuse transmittance, the incident angle of incident light with respect to the normal of the directional forward scattering film is defined as a polar angle θn, and the incident light angle in the in-plane direction of the directional forward scattering film is defined as an azimuth angle φm. The directional forward scattering film has an incident angle (φ1, θ1) at which the diffuse transmittance is minimum and the parallel-line transmitted light is maximized, and an incident angle (φ2) at which the diffuse transmittance is maximized. , Θ2), and the direction facing the directional forward scattering film is an observation direction, and the polar angle and the azimuth angle at which the diffuse transmittance in the directional forward scattering film is maximum are the liquid crystal The directional forward scattering film is disposed on the liquid crystal panel and applied between the substrates so that the polar direction and the azimuth angle at which the parallel line transmittance is maximized are the observation direction. Release voltage The major axis direction of the nematic liquid crystal molecules located in the central portion in the thickness direction of the liquid crystal layer is within a range of ± 30 ° with respect to the azimuth angle direction where the diffuse transmittance is maximum, The major axis direction is a direction in which the liquid crystal molecules respond to an electric field when a voltage is applied between the substrates .

  In a reflection type liquid crystal display device having a directional forward scattering film, a polar angle indicating a maximum transmittance so that an incident light side in the case of a polar angle and an azimuth angle indicating a minimum transmittance is a lighting side of the liquid crystal panel. When the directional forward scattering film is arranged on the liquid crystal panel so that the incident light side in the case of the azimuth angle is the observation direction side of the liquid crystal panel, the minimum transmittance of parallel line transmitted light is shown. The azimuth angle φ2 is the incident angle direction, and the azimuth angle φ1 in the case of showing the maximum transmittance of parallel-line transmitted light is the observer direction. In the case of a liquid crystal display device having a directional forward scattering film arranged in this way, light incident on the directional forward scattering film is strongly scattered at the time of incidence, but is reflected by a reflective layer inside the liquid crystal panel. Since the amount of light scattered when passing through the directional front scattering film later is reduced, there is little influence on display blur (blur), and a clear display form with less display blur (blur) can be obtained.

  Further, in the reflective liquid crystal display device having the directional forward scattering film arranged as described above, the directional forward scattering film exhibits a minimum transmittance of parallel-line transmitted light transmitted through the directional forward scattering film. Since the orientation of the azimuth angle φ2 and the major axis direction of the nematic liquid crystal molecules located at the center of the liquid crystal layer when the voltage applied between the substrates is released, the center of the liquid crystal layer is usually aligned. The major axis direction of the nematic liquid crystal molecules located in the area is the direction in which the contrast is high, and the direction in which this contrast is high is combined with the direction in which the above-mentioned display blur (blur) is seen to be low, so that the blur (bokeh with high contrast) ), A clear display form can be obtained, and display quality can be improved.

  In order to solve the above problems, the present invention can be applied to a transflective liquid crystal device having a transflective layer in place of the reflective layer of the liquid crystal device having the structure described above. .

  Even in a liquid crystal device having a transflective layer, the present invention is effective when performing reflective display, and the azimuth angle φ2 in the case where the minimum transmittance of parallel-line transmitted light is shown is the same as in the previous structure. The azimuth angle φ1 in the incident angle direction and the maximum transmittance of parallel-line transmitted light is in the observer direction. If the directional forward scattering film is arranged in this manner, the light incident on the directional forward scattering film is strongly scattered at the time of incidence, but is reflected by the reflective layer inside the liquid crystal panel and is directed forward. Since the amount of light passing through the scattering film is reduced, a clear display form with little blurring of display can be obtained. Further, in the transflective liquid crystal display device having the directional forward scattering film arranged as described above, the directional forward scattering film has minimal transmission of parallel-line transmitted light transmitted through the directional forward scattering film. The direction of the azimuth angle φ2 indicating the transmittance (diffuse transmitted light exhibits the maximum transmittance) and the major axis direction of the nematic liquid crystal molecules located in the center of the liquid crystal layer when the voltage applied between the substrates is released are aligned. In general, the major axis direction of the nematic liquid crystal molecules located in the central part of the liquid crystal layer is a direction in which the contrast is high, and the direction in which the contrast is high and the direction in which the blur (blurring) of the display appears to be small. As a result, a display with high contrast and no blur is obtained, and thus a clear display form can be obtained and display quality can be improved.

  Moreover, in the liquid crystal device of the present invention having any one of the above-described configurations, the directional forward scattering film has a direction of an azimuth angle φ2 ± 30 degrees in which parallel-line transmitted light transmitted through the directional forward scattering film exhibits a minimum transmittance. In addition, when the voltage applied between the substrates is released, the major axis directions of nematic liquid crystal molecules located at the center of the liquid crystal layer may be aligned.

  In the liquid crystal device according to the present invention having any one of the above-described configurations, the nematic liquid crystal molecules of the liquid crystal layer are set to a twist angle of about 60 to 80 degrees, and the voltage applied between the substrates is released. Sometimes the nematic liquid crystal molecules located in the center of the liquid crystal layer are twisted by about 30 to 40 degrees with respect to the nematic liquid crystal molecules aligned on the substrate surface.

  Moreover, in the liquid crystal device of the present invention having any one of the above structures, the nematic liquid crystal molecules in the liquid crystal layer are set to a twist angle of about 240 to 255 degrees, and the voltage applied between the substrates is released. Sometimes the nematic liquid crystal molecules located in the center of the liquid crystal layer are twisted by about 120 to 127.5 degrees with respect to the nematic liquid crystal molecules aligned on the substrate surface.

In order to solve the above problems, the present invention provides a pair of substrates, a liquid crystal layer sandwiched between the substrates, a reflective layer provided on the liquid crystal layer side of the one substrate, and the other substrate. A liquid crystal panel provided with a directional forward scattering film provided on the opposite side of the liquid crystal layer side, incident light from a light source disposed on one side of the directional forward scattering film, In the light receiving part disposed on the other surface side of the directional forward scattering film, among the total transmitted light transmitted through the directional forward scattering film, when observing parallel line transmitted light excluding diffuse transmitted light,
The incident angle of incident light with respect to the normal of the directional forward scattering film is defined as a polar angle θn, the incident light angle in the in-plane direction of the directional forward scattering film is defined as an azimuth angle φm, and When the maximum transmittance is defined as Tmax (φ1, θ1) and the minimum transmittance of parallel-line transmitted light is defined as Tmin (φ2, θ2), the incident light side in the case of polar angles and azimuths indicating the minimum transmittance The directional forward scattering film is placed on the liquid crystal panel so that the incident light side in the case of the polar angle and the azimuth angle indicating the maximum transmittance is on the observation direction side of the liquid crystal panel. Placed on the panel,
Further, the directional forward scattering film has an incident angle of 10 to 30 degrees with respect to an azimuth angle φ2 direction in which parallel-line transmitted light transmitted through the directional forward scattering film exhibits a minimum transmittance and a polar angle direction. The liquid crystal panel is arranged so that the in-plane directions with high contrast are aligned with light.

  In this reflection type liquid crystal display device, in the case of the polar angle and the azimuth angle indicating the maximum transmittance, the incident light side in the case of the polar angle and the azimuth angle indicating the minimum transmittance becomes the daylighting side of the liquid crystal panel. By arranging the directional forward scattering film on the liquid crystal panel so that the incident light side is on the viewing direction side of the liquid crystal panel, the light incident on the directional forward scattering film is strongly scattered upon incidence. However, since the amount of light scattered when reflected by the reflective layer inside the liquid crystal panel passes through the directional forward scattering film is reduced, there is little effect on display blur (blur) and display blur ( A clear display form with less blur is obtained.

  Further, in the reflective liquid crystal display device having the directional forward scattering film arranged as described above, the directional forward scattering film exhibits a minimum transmittance of parallel-line transmitted light transmitted through the directional forward scattering film. Since the liquid crystal panel is arranged so that the in-plane direction in which the contrast of the liquid crystal panel is high is aligned with respect to the incident light whose azimuth angle φ2 direction and the incident light angle from the polar angle direction are 10 degrees to 30 degrees, the contrast of the liquid crystal panel is reduced. The high direction and the direction in which the blur of the display can be seen are combined, so that a display with high contrast and no blur is obtained, and thus a clear display form can be obtained and display quality can be improved. .

  In order to solve the above problems, the present invention can be applied to a transflective liquid crystal device having a transflective layer in place of the reflective layer of the liquid crystal device having the structure described above. .

  The present invention is effective when performing a reflective display even in a liquid crystal device provided with this transflective layer. As in the case of the previous structure, the azimuth angle φ2 when the minimum transmittance of parallel-line transmitted light is shown. Is the incident angle direction, and the azimuth angle φ1 in the case of indicating the maximum transmittance of parallel-line transmitted light is the observer direction. If the directional forward scattering film is arranged in this manner, the light incident on the directional forward scattering film is strongly scattered at the time of incidence, but is reflected by the reflective layer inside the liquid crystal panel and is directed forward. Since the amount of light passing through the scattering film is reduced, a clear display form with little blurring of display can be obtained.

  Further, in the transflective liquid crystal display device having the directional forward scattering film arranged as described above, the directional forward scattering film has minimal transmission of parallel-line transmitted light transmitted through the directional forward scattering film. The azimuth angle φ2 direction indicating the ratio and the in-plane direction in which the contrast of the liquid crystal panel is high with respect to the incident light with the incident light angle from the polar angle direction of 10 degrees to 30 degrees are aligned. The direction in which the contrast is high and the direction in which the blurring (blurring) of the display is seen are combined, so that a display with high contrast and no blurring (blur) is obtained, and thus a clear display form is obtained and the display quality is improved. Can be improved.

  Moreover, in the liquid crystal device of the present invention having any one of the above-described configurations, the directional forward scattering film has a direction of an azimuth angle φ2 ± 30 degrees in which parallel-line transmitted light transmitted through the directional forward scattering film exhibits a minimum transmittance. The in-plane direction in which the contrast of the liquid crystal panel is high with respect to the incident light with the incident light angle from the polar angle direction of 10 degrees to 30 degrees may be aligned.

  In order to solve the above-described problems, the present invention provides a liquid crystal device according to any one of the above-described configurations, wherein the ratio of the maximum transmittance Tmax and the minimum transmittance Tmin of the parallel-line transmitted light is set to (Tmax / Tmin). ) ≧ 2.

  By satisfying the relationship of (Tmax / Tmin) ≧ 2, sufficient scattering can be obtained at the time of incidence of light in the directional forward scattering film, so that the display is brighter than a liquid crystal device having a conventional isotropic forward scattering film. A clear (clear) display can be obtained.

  In order to solve the above problems, in the liquid crystal device according to the present invention having any one of the above-described configurations, a liquid crystal driving electrode is provided on the liquid crystal layer side of the one substrate and the liquid crystal layer side of the other substrate. It is characterized by.

  According to such a liquid crystal device, it is possible to switch between display, non-display, and halftone display by controlling the alignment state of the liquid crystal by electrodes sandwiching the liquid crystal layer.

  In order to solve the above-described problems, the present invention may be the liquid crystal device of the present invention having any one of the above-described structures, in which a color filter is provided on one liquid crystal layer side of the pair of substrates.

  According to such a liquid crystal device, it is possible to perform color display by providing a color filter, and by adopting any of the structures described above, there is a device that has a clear color display with high contrast and little display blur. can get.

  In the present invention, when the reflective layer has fine irregularities, the incident light is strongly scattered and guided to the reflective layer. Therefore, the glare sensation generated because the reflective layer has fine irregularities. Furthermore, since the reflected light from the reflective layer is not strongly scattered by the directional forward scattering film, a clear display with less display blur can be obtained.

  In order to solve the above-described problems, an electronic apparatus according to the present invention includes the liquid crystal device according to the present invention having any one of the above configurations as a display unit.

  By providing the above-described liquid crystal device of the present invention with an excellent display form, such an electronic device can be obtained with a display form having a high contrast, a display blur and a clear display. .

  As described above, according to the liquid crystal device of the present invention, in the reflective or transflective liquid crystal display device provided with the directional forward scattering film, the incident light side in the case of the polar angle and the azimuth angle indicating the minimum transmittance. The directional forward scattering film on the liquid crystal panel so that the incident light side in the polar angle and azimuth angle indicating the maximum transmittance is on the observation direction side of the liquid crystal panel By arranging, the azimuth angle φ2 when showing the minimum transmittance of parallel line transmitted light is the incident angle direction, and the azimuth angle φ1 when showing the maximum transmittance of parallel line transmitted light is the observer direction. In the case of a liquid crystal display device having a directional forward scattering film arranged in this way, light incident on the directional forward scattering film is strongly scattered at the time of incidence, but is reflected by a reflective layer inside the liquid crystal panel. Since the amount of light scattered when passing through the directional front scattering film later is reduced, there is little influence on display blur (blur), and a clear display form with less display blur (blur) can be obtained.

  Further, in the reflective or transflective liquid crystal display device including the directional forward scattering film arranged as described above, the directional forward scattering film is a parallel-line transmitted light transmitted through the directional forward scattering film. Is arranged such that the direction of the azimuth angle φ2 indicating the minimum transmittance and the major axis direction of the nematic liquid crystal molecules located in the center of the liquid crystal layer when the voltage applied between the substrates is released are aligned, The major axis direction of the nematic liquid crystal molecules located in the center of the liquid crystal layer is a direction with high contrast, and the direction in which this contrast is high and the direction in which the blurring (blurring) of the display is seen are combined. A display without blur is obtained, and thus a clear display form can be obtained and display quality can be improved.

  Further, in the reflective or transflective liquid crystal display device including the directional forward scattering film arranged as described above, the directional forward scattering film is a parallel-line transmitted light transmitted through the directional forward scattering film. Is arranged so that the in-plane direction in which the contrast of the liquid crystal panel is high is aligned with respect to the azimuth angle φ2 direction where the minimum transmittance is incident and the incident light angle from the polar angle direction is 10 degrees to 30 degrees. Therefore, the direction in which the contrast of the liquid crystal panel is high and the direction in which the blurring (blurring) of the above-mentioned display is seen are combined, so that a display with high contrast and no blurring (blur) is obtained. , Display quality can be improved.

  Furthermore, if the electronic apparatus has the liquid crystal device having the various structures described above, it is possible to provide an electronic apparatus that can display a high-contrast and sharp high-quality image without blurring of display. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment of Liquid Crystal Device)
A liquid crystal panel according to a first embodiment of the liquid crystal device according to the present invention will be described below with reference to FIGS. FIG. 1 is a plan view showing a first embodiment in which the present invention is applied to a simple matrix type reflective liquid crystal panel, and FIG. 2 is a partial sectional view taken along line AA of the liquid crystal panel shown in FIG. FIG. 3 is an enlarged cross-sectional view of a color filter portion built in the liquid crystal display device. A liquid crystal display device (liquid crystal device) as a final product is configured by mounting auxiliary elements such as a liquid crystal driving IC and a support on the liquid crystal panel 10 of this embodiment.

  The liquid crystal panel 10 of this embodiment has a substantially rectangular shape in plan view, and a pair of rectangular plan view substrate units 13 and 14 attached so as to face each other with a cell gap therebetween via an annular sealing material 12. A liquid crystal layer 15 surrounded and sandwiched together with the sealing material 12 therebetween, a directional forward scattering film 18 and a retardation plate provided on the upper surface side of one (upper side in FIG. 2) substrate unit 13 19 and the polarizing plate 16 are mainly used. Of the substrate units 13 and 14, the substrate unit 13 is a front (upper) substrate unit provided toward the observer side, and the substrate unit 14 is provided on the opposite side, in other words, on the back side (lower). It is.

  The upper substrate unit 13 includes, for example, a substrate 17 made of a transparent material such as glass, a directional forward scattering film 18 provided on the front side of the substrate 17 (the upper surface side and the observer side in FIG. 2), and a retardation plate. 19 and the polarizing plate 16, the color filter layer 20 and the overcoat layer 21 sequentially formed on the back side of the substrate 17 (in other words, the liquid crystal layer 15 side), and the overcoat layer 21 formed on the surface on the liquid crystal layer 15 side. In addition, a plurality of striped electrode layers 23 for driving the liquid crystal are provided.

  The liquid crystal layer 15 is composed of nematic liquid crystal molecules having a twist angle θt of 240 degrees to 255 degrees.

  In an actual liquid crystal device, alignment films are formed on the liquid crystal layer 15 side of the electrode layer 23 and the liquid crystal layer 15 side of the striped electrode layer 35 on the lower substrate side, which will be described later. Then, while omitting these alignment films and abbreviate | omitting description, illustration and description of an alignment film are abbreviate | omitted also in other embodiment demonstrated sequentially below. The cross-sectional structure of the liquid crystal device shown in FIG. 2 and the following drawings is shown by adjusting the thickness of each layer to a thickness different from that of an actual liquid crystal device so that the layers can be easily seen in the illustrated case.

  In the present embodiment, each electrode layer 23 for driving on the upper substrate side is formed from a transparent conductive material such as ITO (Indium Tin Oxide) in a stripe shape in plan view. The required number is formed according to the area and the number of pixels.

  In the present embodiment, the color filter layer 20 is enlarged on the lower surface of the upper substrate 17 (in other words, the surface on the liquid crystal layer 15 side), as shown in FIG. Each of the RGB patterns 27 is formed. The overcoat layer 21 is covered as a transparent protective flattening film for protecting the RGB pattern 27.

  Such a black mask 26 is formed by patterning a metal thin film of chromium or the like having a thickness of about 100 to 200 nm by, for example, a sputtering method, a vacuum deposition method or the like. Each of the RGB patterns 27 has a red pattern (R), a green pattern (G), and a blue pattern (B) arranged in a desired pattern shape. For example, a pigment using a photosensitive resin containing a predetermined colorant It is formed by various methods such as a dispersion method, various printing methods, electrodeposition methods, transfer methods, and dyeing methods.

  On the other hand, the lower substrate unit 14 is sequentially formed on a substrate 28 made of a transparent material such as glass or other opaque material, and on the surface side of the substrate 28 (the upper surface side in FIG. 2, in other words, the liquid crystal layer 15 side). The reflective layer 31, the overcoat layer 33, and a plurality of striped driving electrode layers 35 formed on the surface of the overcoat layer 33 on the liquid crystal layer 15 side. In these electrode layers 35, the required number is formed in accordance with the display area and the number of pixels of the liquid crystal panel 10 as in the case of the previous electrode layer 23.

  Next, the reflective layer 31 of the present embodiment is made of a metal material having excellent light reflectivity and conductivity such as Ag or Al, and is formed on the substrate 28 by vapor deposition or sputtering. However, it is not essential that the reflective layer 31 is made of a conductive material, and a structure in which a drive electrode layer made of a conductive material is provided separately from the reflective layer 31 and the reflective layer 31 and the drive electrode are provided separately may be employed. Absent.

  Next, the directional forward scattering film 18 attached to the upper substrate unit 13 will be described in detail below.

  The directional forward scattering film 18 used in the present embodiment has the directivity disclosed in JP 2000-035506, JP 2000-066066, JP 2000-180607, etc. from the viewpoint of the basic structure. A front scattering film can be used as appropriate. For example, as disclosed in JP-A-2000-035506, a resin sheet that is a mixture of two or more kinds of photopolymerizable monomers or oligomers having different refractive indexes is irradiated with ultraviolet rays from a specific direction. As an on-line holographic diffusion sheet having a function of efficiently scattering only in a wide direction, or as an on-line holographic diffusion sheet disclosed in Japanese Patent Application Laid-Open No. 2000-0666026, the hologram photosensitive material is irradiated with a laser so that the refractive index is partially What manufactured the different area | region so that it might become a layer structure etc. can be used suitably.

  Here, the directional forward scattering film 18 used in the present embodiment has various parameters such as parallel line transmittance described below in a specific positional relationship suitable for a liquid crystal display device.

  First, as shown in FIG. 4, the directional forward scattering film 18 having a rectangular shape in plan view is installed horizontally. In FIG. 4, since the horizontal installation state is easy to explain, the horizontal installation state will be described. However, the direction in which the directional front scattering film 18 is installed is not limited to the horizontal direction, and may be any direction. The positional relationship between K, the light receiving part J, and the directional forward scattering film 18 (the polar angle θ and the azimuth angle φ, which will be described later) can be clearly defined, and the parallel-line transmitted light exhibits the minimum transmittance (diffuse transmitted light is The direction of the azimuth angle φ2 (indicating the maximum transmittance) and the major axis direction of the nematic liquid crystal molecules located in the center of the liquid crystal layer 15 can be aligned, and the parallel line transmitted light exhibits the minimum transmittance (diffuse transmitted light is maximum) It only needs to be arranged so that the in-plane direction in which the contrast of the liquid crystal panel is high is aligned with respect to the incident light having an azimuth angle φ2 direction (indicating the transmittance) and the incident light angle from the polar angle direction of 10 degrees to 30 degrees. In the present embodiment, the horizontal direction installation of the directional forward scattering film 18 will be described as an example as a direction in which the direction can be easily understood in the description.

  In FIG. 4, it is assumed that incident light L <b> 1 from the light source K enters from the diagonally upper right rear side of the directional forward scattering film 18 toward the origin O at the center of the directional forward scattering film 18. A measurement system is assumed in which transmitted light that passes through the origin O of the directional forward scattering film 18 and passes through the directional forward scattering film 18 and travels straight is received by the light receiving unit J such as an optical sensor.

  Here, in order to specify the direction of the incident light L1 to the directional forward scattering film 18, the directional forward scattering film 18 is rectangular with the coordinate axes of 0 °, 90 °, 180 °, and 270 ° as shown in FIG. Is divided into four equal parts and passes through the center origin O (in other words, the center of each side of the directional forward scattering film 18 is divided into four parts so that one end of the coordinate axis passes) The horizontal rotation angle of the incident light L1 vertically projected onto the surface of the directional forward scattering film 18 (a clockwise angle from the 0 ° coordinate axis is +, and a counterclockwise angle from the 0 ° coordinate axis is −). ) Is defined as the azimuth angle φ. Next, the normal H of the directional forward scattering film with respect to the direction of the incident light L1 that is horizontally projected onto a vertical plane (a plane indicated by reference numeral M1 in FIG. 4) including the coordinate axes of 0 ° and 180 °. The angle formed is defined as the polar angle θ of the incident light L1. In other words, the polar angle θ indicates the incident angle of the incident light L1 in the vertical plane with respect to the directional forward scattering film 18 installed horizontally, and the azimuth angle φ corresponds to the rotation angle of the incident light L1 in the horizontal plane.

  In this state, for example, when the polar angle of the incident light L1 is 0 ° and the azimuth angle is 0 °, the incident light L1 enters the directional front film 18 at a right angle as shown in FIG. The directional forward scattering film 18 is in the state indicated by reference numeral 18 in FIG. 5 and when the polar angle θ is + 60 °, the light source K, the light receiving part J, the directional forward film 18 and the like. 5 is in a state in which the directional forward scattering film 18 is arranged as shown by reference numeral 18A in FIG. 5, and when the polar angle θ is −60 °, the light source K, the light receiving portion J, the directional forward scattering film 18 and the like. This means that the directional forward scattering film 18 is placed as shown by reference numeral 18B.

  Next, the incident light L1 emitted from the light source installed on one side of the directional forward scattering film 18 (left side in FIG. 6A) is applied to the directional forward scattering film 18 as shown in FIG. 6A. When passing through the other side of the directional front scattering film 18 (right side in FIG. 6A), the light scattered on one side (left side) of the directional front scattering film 18 is referred to as backscattered light LR. Light that passes through the directional forward scattering film 18 is referred to as forward scattered light. Then, with respect to the forward scattered light transmitted through the directional forward scattering film 18, the light of the forward scattered light (parallel transmitted light) L3 that travels straight in the same direction with an angle error within ± 2 ° with respect to the traveling direction of the incident light L1. Regarding the intensity, the ratio of the incident light L1 to the light intensity is defined as the parallel line transmittance, and further, the light intensity of the forward scattered light (diffused transmitted light) LT that is diffused obliquely to the peripheral side exceeding ± 2 ° is incident. The ratio of the light L1 to the light intensity is defined as the diffuse transmittance, and the ratio of the entire transmitted light to the incident light is defined as the total light transmittance. From the above definition, it can be defined that the parallel light transmittance is obtained by subtracting the diffuse transmittance from the total light transmittance. In order to make the above explanation easier to understand, FIG. 1 also shows the relationship between the incident light L1, the azimuth angle φ, and the parallel-line transmitted light L3.

  In addition, in the field of optics, a transmittance scale called “haze” is also generally known. However, haze is a value obtained by dividing diffuse transmittance by total light transmittance and expressing it in%. The definition of the concept is completely different from the parallel line transmittance used in the present embodiment.

  Next, when the maximum transmittance of the parallel line transmittance is marked using the previous polar angle θ and the azimuth angle φ, it is defined as Tmax (φ1, θ1), and the minimum transmittance of the parallel line transmittance is defined. Is defined as Tmin (φ2, θ2). In other words, due to the nature of the directional forward scattering film, the conditions for the maximum transmittance are the weakest conditions for scattering and the conditions for the minimum transmittance are the conditions for strongest scattering.

  For example, if the maximum transmittance is shown when the polar angle θ = 0 ° and the azimuth angle = 0 °, it is denoted as Tmax (0, 0). (This means that the parallel transmission along the normal direction of the directional forward scattering film is maximum. In other words, the scattering along the normal direction of the directional forward scattering film is the weakest. In addition, when the minimum transmittance is shown when the polar angle θ = 10 ° and the azimuth angle = 45 °, it is denoted as Tmin (10, 45), which means that the scattering in this direction is the strongest. .

  Based on the above definition, each characteristic of the directional forward scattering film 18 that is preferably applied to the liquid crystal device will be described below.

  As described above, in the directional forward scattering film 18, the angle at which the parallel line transmittance exhibits the maximum transmittance is the angle at which the scattering is the weakest, and the angle at which the minimum transmittance is exhibited is the angle at which the scattering is strongest.

  Therefore, in other words, as shown in FIG. 2, in the reflective liquid crystal display device, it is considered that the ambient light with respect to the liquid crystal panel 10 is used as the incident light L1, and the light reflected by the reflective layer 31 is recognized as reflected light. 4, the incident light enters the liquid crystal panel 10 from a direction in which scattering is strong when light is incident (in other words, a direction having a low parallel-line transmittance), and the scattering is weak when an observer observes the reflected light. When viewed from the direction (in other words, the direction of high parallel line transmittance), it is considered that a state with little blurring of display can be obtained. This is because the first scattering upon incidence on the directional forward scattering film 18 found by the present inventors hardly affects the blurring of the display, but the directional forward scattering film 18 is reflected as reflected light. This is based on the knowledge that the scattering when passing through the second time has a large effect on the blurring of the display.

  That is, in the present embodiment, when the incident light L1 passes through the directional forward scattering film 18 for the first time, the direction of scattering the light (the more diffuse transmitted light) is the regular reflection (mirror reflection) of the reflection layer 31. Is preferable for the purpose of obtaining a bright display with a wide viewing angle by preventing light, and when the light reflected by the reflective layer 31 inside the liquid crystal device passes through the directional forward scattering film 18 for the second time. This is because less scattering is considered preferable in order to reduce display blur. Accordingly, in the characteristics of the directional forward scattering film 18, the polar angle and azimuth indicating the minimum transmittance, in other words, the polar angle and azimuth direction of the incident light having the strongest scattering (the polar angle and azimuth indicating the maximum diffuse transmittance). It is preferable that the angle is directed to the daylighting side of the liquid crystal panel 10, in other words, the direction opposite to the viewer side, and the polar angle and azimuth angle (diffuse transmittance is minimum) where the parallel line transmittance indicates the maximum transmittance. The polar angle and the azimuth angle), in other words, the incident light angle and the incident direction with the weakest scattering must be directed to the viewer side of the liquid crystal panel 10.

  Here, FIG. 6B shows a cross-sectional structure of the directional forward scattering film 18 used in the present embodiment, and the state of the polar angle and the azimuth as described above will be described.

  As shown in FIG. 6B, the cross-sectional structure model of the directional forward scattering film 18 used in the present embodiment is the cross-sectional structure of the directional forward scattering film 18 where the refractive index is n1 and the refractive index is n2. It is a structure in which layers are arranged alternately in a slanting direction at a predetermined angle. If the incident light L1 is incident on the directional forward scattering film 18 having this structure with an appropriate polar angle from an oblique direction, the incident light L1 is scattered at the boundary portion of each layer having a different refractive index and a part of the scattered light. When the light passes through the liquid crystal layer 15 and is reflected by the reflective layer 31, the reflected light L2 passes through the liquid crystal layer 15 again and passes through the directional forward scattering film 18 at a polar angle different from the incident light L1. However, the reflected light L2 here can pass through the directional forward scattering film 18 with little scattering.

  In order to satisfy such a relationship, the relationship between the azimuth angles φ1 and φ2 is most preferably φ1 = φ2 ± 180 °. This means that φ2 is the incident angle direction and φ1 is the viewing direction, and these angles differ by 180 ° when applied in an actual liquid crystal device. In this case, the light incident on the liquid crystal device is strongly scattered at the time of incidence, and the light reflected by the reflective layer 31 is not easily scattered, so that a sharp display form without blurring (blur) of the display can be obtained. However, in consideration of the fact that the directional forward scattering film 18 in which layers having different refractive indexes are alternately arranged in an oblique direction and having a predetermined angle as described above is not systematically completely uniform. The ideal relationship between the angles φ1 and φ2 is φ1 = φ2 ± 180 °, but the present invention is based on the relationship φ1 = φ2 ± 180 ° and is shifted by about (± 10) ° from the angle. Then it shall be included. If this angle deviates by more than (± 10) °, it becomes difficult to obtain a sharp display form without blurring (blurring) of display.

  Next, it is preferable that the value of (Tmax / Tmin) satisfies the relationship of (Tmax / Tmin) ≧ 2. With this relationship, sufficient scattering can be obtained at the time of incidence, and a bright and sharp reflective display can be obtained. Further, by satisfying this relationship, it is possible to realize a reflective display that is brighter than when a conventionally known isotropic scattering film is used.

  Next, when the polar angles θ1 and θ2 are individually viewed, in order to obtain a brighter display than the isotropic scattering film, the range of −40 ° ≦ θ1 <0 ° and 0 ° <θ2 ≦ + 40 ° Preferably, the ranges of −30 ° ≦ θ1 ≦ −10 ° and 10 ° ≦ θ2 ≦ 30 ° are preferable.

  Next, when the parallel line transmittance in the normal direction of the directional front scattering film 18 is defined as T (0, 0), a brighter display than the conventionally known isotropic scattering film is obtained. In order to obtain, when θ1 = −20 ° and θ2 = 20 °, T (0,0) is preferably 3% or more and 50% or less, and T (0,0) is 5% or more, More preferably, it is 40% or less. If T (0, 0) is less than 3%, the scattering is too strong and the display is blurred. If T (0, 0) exceeds 40%, the front scattering is too weak and the mirror reflection is close.

  Next, when the azimuth angle φ of the directional forward scattering film is defined as a range of φ1 ± 60 ° (φ2 ± 60 °), the maximum of the parallel line transmittance is always taken at θ1, and the minimum of the parallel line transmittance is taken at θ2. It is preferable to take a value and set the ratio between the maximum value and the minimum value to 1.5 or more. If it has such a feature, it is possible to scatter light up to ± 60 ° not only in one direction of φ2 but also in an azimuth angle, so it is easy to cope with each environment. Bright display can be realized.

  Next, when the polar angle θ in the direction orthogonal to the azimuth angle φ1 indicating the maximum transmittance and the azimuth angle φ2 indicating the minimum transmittance is changed from −40 ° to + 40 °, the parallel line transmittance is directed in this range. If the transmittance is equal to or higher than the transmittance of the normal forward scattering film in the normal direction, a sharp display without blurring of display can be obtained even when the liquid crystal device is observed from the lateral direction. That is, it is preferable to satisfy the relationship of T (0,0) ≦ T (φ1 ± 90, θ) and satisfy the relationship of T (0,0) ≦ T (φ2 ± 90, θ).

  Next, when the polar angle θ is in the range of −60 ° ≦ θ ≦ + 60 °, the parallel line transmittance T (φ, θ) is 2% or more and preferably 50% or less. That is, it is preferable to satisfy the relationship of 2% ≦ T (φ, θ) ≦ 50%, but −60 ° ≦ θ ≦ + 60 °. With such a relationship, it is possible to obtain a bright and sharp display with no blurring of display.

  Further, as shown in FIG. 15, the directional forward scattering film 18 has a minimum transmittance for the parallel-line transmitted light L3 transmitted through the directional forward scattering film 18 (the diffuse transmitted light LT shows the maximum transmittance). Arranged so that the direction of the angle φ2 and the major axis direction α of the nematic liquid crystal molecules 15a located at the center in the thickness direction of the liquid crystal layer 15 are aligned between the substrates 17 and 28 when no electric field is applied (when the applied voltage is released). Has been. Since the liquid crystal molecules 15a have a twist angle θt of 240 ° to 255 ° as described above, the liquid crystal layer 15 has a central portion in the thickness direction of the liquid crystal layer 15 when there is no electric field between the substrates (when the applied voltage is released). The nematic liquid crystal molecules 15a positioned are twisted at a twist angle θtm of 120 ° to 127.5 °, and the major axis direction α at the twist angle θtm is aligned with the azimuth angle φ2 direction.

  The direction of the thickness of the liquid crystal layer 15 when the parallel-line transmitted light L3 transmitted through the directional forward scattering film 18 has the minimum azimuth angle φ2 direction and when there is no electric field between the substrates (when the applied voltage is released). The angle formed by the major axis direction α of the nematic liquid crystal molecules 15a located at the center may not be 0 degrees, but may be within a range of ± 30 degrees. In other words, the direction of the azimuth angle φ2 ± 30 degrees at which the parallel-line transmitted light L3 transmitted through the directional forward scattering film 18 exhibits the minimum transmittance and the voltage applied to the substrates 17 and 28 are released. It suffices that the long axis directions α of nematic liquid crystal molecules located at the center are aligned.

  Thus, the directional forward scattering film 18 is such that the azimuth angle φ2 direction in which the parallel-line transmitted light L3 exhibits the minimum transmittance and the major axis direction α of the nematic liquid crystal molecules 15a located at the center of the liquid crystal layer 15 are substantially aligned. The long axis direction α of the nematic liquid crystal molecules 15a located at the center of the liquid crystal layer 15 when no electric field is applied (when the applied voltage is released) is a high contrast direction. Thus, the direction in which the display blur (blur) is seen is adjusted, and a display with high contrast and no blur (blur) can be obtained. Therefore, a clear display form can be obtained and display quality can be improved.

  Further, the directional forward scattering film 18 has a azimuth angle φ2 direction in which the parallel-line transmitted light L3 transmitted through the directional front film 18 exhibits the minimum transmittance (the diffuse transmitted light LT indicates the maximum transmittance) and the polar angle. The liquid crystal panel 10 is arranged so that the in-plane direction in which the contrast of the liquid crystal panel 10 is high is uniform with respect to the incident light having an incident light angle of 10 degrees to 30 degrees from the θ direction.

  A liquid crystal panel with respect to incident light having an incident light angle of 10 degrees to 30 degrees from an azimuth angle φ2 direction in which parallel-line transmitted light L3 transmitted through the directional forward scattering film 18 exhibits a minimum transmittance. The angle formed by the in-plane direction with a high contrast of 10 does not have to be 0 degrees, and may be within a range of ± 30 degrees. In other words, the incident light having the azimuth angle φ2 ± 30 degrees in which the parallel-line transmitted light L3 transmitted through the directional forward scattering film 18 exhibits the minimum transmittance and the incident light angle from the polar angle direction of 10 degrees to 30 degrees. The liquid crystal panel may be arranged so that the in-plane directions with high contrast are aligned.

  Thus, the directional forward scattering film 18 has an incident light angle of 10 degrees from the azimuth angle φ2 direction in which the parallel-line transmitted light transmitted through the directional forward scattering film 18 exhibits the minimum transmittance and the polar angle θ direction. By arranging the liquid crystal panel 10 so that the in-plane direction with high contrast is aligned with respect to incident light of 30 degrees, the liquid crystal panel 10 includes a direction including the region with high contrast and blurring of the display (blur). As a result, a display with high contrast and no blur is obtained, and thus a clear display form can be obtained and display quality can be improved.

  FIG. 16 is a diagram showing contrast characteristics when incident light is incident on the liquid crystal panel 10 of the present embodiment at a polar angle of 20 degrees and an azimuth angle of 0 degrees. The azimuth angle of the incident light at this time is the azimuth angle φ2 direction in which the parallel-line transmitted light transmitted through the directional forward scattering film 18 exhibits the minimum transmittance (diffuse transmitted light exhibits the maximum transmittance). The center of the concentric circle shown in FIG. 16 is the viewing angle in the normal direction of the liquid crystal panel 10, the viewing angle when the outermost circle is viewed from a direction inclined by 80 degrees from the normal direction H, and the second circle from the outside is the normal line. Viewing angle viewed from a direction inclined 60 degrees from direction H, viewing angle viewed from a direction in which the third circle from the outside is inclined 40 degrees from normal direction H, and direction in which the innermost circle is inclined 20 degrees from normal direction H This represents the viewing angle seen from. In FIG. 16, a region 3) indicated by hatching indicates that a contrast of 1:10 or more can be obtained.

  FIG. 16 shows a contrast of 1:10 with respect to incident light from the azimuth angle φ2 direction even when the observer's viewing angle is tilted 40 degrees from the normal direction, and the viewing angle is 30 degrees to 0 degrees from the normal direction. Even if it is tilted, it can show a contrast of 1:10 or more with respect to incident light from the direction of the azimuth angle φ2. When observing a liquid crystal panel, the observer usually observes the display from a direction deviated from the regular reflection direction of incident light, in other words, from the direction near the normal line or the direction closer to the normal direction than the regular reflection direction. As in the liquid crystal panel of the present embodiment, the liquid crystal panel 10 is arranged so that the in-plane direction γ where the contrast of the liquid crystal panel 10 is high is aligned with the azimuth angle φ2 direction and the incident light having an incident light angle of 10 to 30 degrees from the polar angle θ direction. As shown in FIG. 16, the contrast is high when the viewing angle is 30 degrees to 0 degrees from the normal direction, and the display quality can be improved.

  Further, with respect to the incident light having the azimuth angle φ2 ± 30 degrees at which the parallel-line transmitted light L3 transmitted through the directional forward scattering film 18 exhibits the minimum transmittance and the incident light angle from the polar angle direction of 10 to 30 degrees. When the liquid crystal panel is arranged so that the in-plane direction γ with high contrast is aligned, it can be seen from FIG. 16 that the contrast is high when the viewing angle is 30 degrees to 0 degrees from the normal direction.

(Second Embodiment of Liquid Crystal Device)
FIG. 7 is a partial cross-sectional view showing a liquid crystal panel 40 of a second embodiment of the liquid crystal device according to the present invention.

  The liquid crystal panel 40 of this embodiment has a reflective simple matrix structure having a directional forward scattering film 18 as in the liquid crystal panel 10 of the first embodiment described with reference to FIGS. Since the basic structure is the same as that of the first embodiment, the same components are denoted by the same reference numerals, description thereof will be omitted, and different components will be mainly described below.

  The liquid crystal panel 40 of the present embodiment is configured by sandwiching the liquid crystal layer 15 between the substrate unit 41 and the substrate unit 42 opposed to each other, surrounded by the sealing material 12. The upper substrate unit 41 is obtained by omitting the color filter layer 20 from the substrate unit 13 of the first embodiment, and the color filter layer 20 is formed on the reflective layer 31 of the lower substrate unit 42 on the opposite side. The structure of this portion is different from the structure of the first embodiment. That is, in the liquid crystal panel 40 shown in FIG. 4, the color filter layer 20 provided on the upper (observer side) substrate unit 13 side in the first embodiment is arranged below the liquid crystal layer 15 (the observer side). This is a structure provided on the substrate unit 42 side on the opposite side. The structure of the color filter layer 20 is the same as that of the first embodiment. However, since the color filter layer 20 is formed on the upper surface side of the substrate 28, the laminated structure of the color filter layer 20 shown in FIG. The state is upside down.

  Also in the structure of the second embodiment, the directional forward scattering film 18 has the structure and arrangement of the first embodiment (the azimuth angle φ2 direction in which the parallel-line transmitted light L3 exhibits the minimum transmittance and the distance between the substrates are not present. When the electric field is applied (when the applied voltage is released), the long axis direction α of the nematic liquid crystal molecules 15a located at the center of the liquid crystal layer 15 is aligned with the direction of the azimuth angle φ2 in which the parallel-line transmitted light indicates the minimum transmittance. The liquid crystal panel 40 has a high in-plane direction in which the contrast of the liquid crystal panel 40 is adjusted with respect to incident light having an incident light angle of 10 to 30 degrees from the polar angle θ direction. An effect equivalent to the structure of the first embodiment can be obtained with respect to blur and blur.

  In the liquid crystal device 40 shown in FIG. 4, since the color filter layer 20 is formed immediately above the reflective layer 31, the light incident on the liquid crystal device 40 reaches the reflective layer 31 via the liquid crystal layer 15 and is reflected. Since it passes through the color filter 32 immediately after being done, it has a feature that the problem of color misregistration hardly occurs.

  In the present embodiment, the reflective layer 31 is in a mirror (mirror surface) state, but may have fine irregularities of about 1 to 20 μm.

(Third embodiment of liquid crystal device)
FIG. 8 is a cross-sectional view showing a liquid crystal panel 50 of a third embodiment of the liquid crystal device according to the present invention.

  The liquid crystal panel 50 of this embodiment is a substrate unit provided with a transflective layer 52 in place of the reflective layer 31 provided in the liquid crystal panel 10 of the first embodiment described with reference to FIGS. 55 having a translucent reflection type simple matrix structure provided with 55, and in the other basic structure, the same reference numerals are given to the same parts as those in the first embodiment, and the description of those components is omitted. Hereinafter, different components will be mainly described.

  The liquid crystal panel 50 is different from the structure of the first embodiment in that a transflective layer 52 is provided, and a light source 60 such as a backlight is provided behind the liquid crystal panel 50 (lower side in FIG. 8). And a phase difference plate 56 and a polarizing plate 57 are arranged.

  When the liquid crystal display device is used as the transmission type, the lower substrate 28 ′ needs to be made of a transparent substrate such as glass.

  The semi-transmissive reflective layer 52 is a semi-transmissive reflective layer having a sufficient thickness to pass the transmitted light emitted from the light source 60 such as a backlight on the back side (lower side in FIG. 8), or a part of the reflective film. For example, a structure widely used in a transflective liquid crystal display device, such as a structure in which a large number of fine through-holes are formed to enhance light transmittance, can be used as appropriate.

  The liquid crystal device according to the third embodiment takes a transmissive liquid crystal display form when using light transmitted from a light source 60 such as a backlight, and reflects using ambient light when light from the light source is not used. By performing display, it can be used as a reflective liquid crystal display device. Also in the structure of the third embodiment, the directional forward scattering film 18 has the structure and arrangement of the first embodiment (the azimuth angle φ2 direction in which the parallel-line transmitted light L3 indicates the minimum transmittance and the distance between the substrates). Is aligned with the major axis direction α of the nematic liquid crystal molecules 15a located at the center of the liquid crystal layer 15 when no electric field is applied (when the applied voltage is released), and the azimuth angle φ2 at which the parallel line transmitted light exhibits the minimum transmittance. And the in-plane direction in which the contrast of the liquid crystal panel 50 is high with respect to incident light with an incident light angle of 10 degrees to 30 degrees from the polar angle θ direction). In the case of adopting a display form as a liquid crystal display device, as in the case of the first embodiment, it is possible to obtain a sharp reflective display form that eliminates blurring of display and reduction in contrast. .

  In the first, second, and third embodiments described so far, the example in which the present invention is applied to the simple matrix reflective liquid crystal display device has been described. However, the present invention is not limited to a two-terminal switching element or 3 Of course, the present invention may be applied to an active matrix reflective liquid crystal display device or a transflective liquid crystal display device having a terminal type switching element.

  When applied to these active matrix liquid crystal display devices, a common electrode is provided on one substrate side instead of the striped electrodes shown in FIGS. 2, 7, and 8, and a large number of pixels are provided on the other substrate side. An electrode is provided for each pixel, and each pixel electrode is individually driven by a thin film transistor that is a three-terminal switching element. A TFT (thin film transistor) drive type structure, a striped electrode is provided on one substrate side, and the other Needless to say, the present invention can be applied to a liquid crystal display device of a two-terminal type linear element driving type in which a pixel electrode is provided for each pixel on the substrate side, and these pixel electrodes are individually driven by a thin film diode that is a two-terminal type linear element. In any of these types of liquid crystal display devices, the present invention can be applied simply by disposing the directional forward scattering film in the specific direction as described above. It has a feature that can be applied to a liquid crystal display device of various forms.

  When the liquid crystal device of the present invention is applied to an active matrix type liquid crystal display device, nematic liquid crystal molecules constituting the liquid crystal layer can be those having a twist angle set between 60 degrees and 80 degrees, and the directivity in this case As shown in FIG. 17, the forward scattering film has a azimuth angle φ2 direction in which parallel-line transmitted light that has passed through the directional forward scattering film exhibits minimum transmittance (diffuse transmitted light exhibits maximum transmittance), and the distance between the substrates is When no electric field is applied (when the applied voltage is released), the major axis directions β of the nematic liquid crystal molecules 15b located at the center in the thickness direction of the liquid crystal layer are arranged to be aligned. Since the liquid crystal molecules 15b have a twist angle θt of 60 ° to 80 ° as described above, the liquid crystal layer 15b is positioned at the central portion in the thickness direction of the liquid crystal layer when there is no electric field (when the applied voltage is released). The nematic liquid crystal molecules 15b are twisted at a twist angle θtm of 30 to 40 degrees, and the major axis direction β at the twist angle θtm is aligned with the azimuth angle φ2 direction.

  Further, the direction of the thickness of the liquid crystal layer 15 when the parallel-line transmitted light that has passed through the directional forward scattering film exhibits a minimum transmittance and the azimuth angle φ2 direction between the substrates and when there is no electric field (when the applied voltage is released). The angle formed by the major axis direction β of the nematic liquid crystal molecules 15b located at the center may not be 0 degrees, but may be within a range of ± 30 degrees. In other words, the direction of the azimuth angle φ2 ± 30 degrees at which the parallel-line transmitted light transmitted through the directional forward scattering film shows the minimum transmittance, and the nematic located at the center of the liquid crystal layer when the voltage applied between the substrates is released It is sufficient that the liquid crystal molecules are arranged so that the major axis directions β thereof are aligned.

  In the above-described embodiment, the directional forward scattering film has an azimuth angle φ2 direction in which parallel-line transmitted light transmitted through the directional forward scattering film exhibits a minimum transmittance, and no electric field is applied between the substrates. When the applied voltage is released), the long axis direction of the nematic liquid crystal molecules located at the center of the liquid crystal layer is aligned, and the parallel-line transmitted light has an azimuth angle φ2 direction indicating the minimum transmittance, The case where the incident light angle from the angle θ direction is arranged so that the in-plane direction in which the contrast of the liquid crystal panel is high with respect to incident light with an angle of 10 to 30 degrees is aligned, the directional forward scattering film is the above-mentioned The azimuth angle φ2 direction is arranged so that the substrate is aligned with the major axis direction of the nematic liquid crystal molecules located in the center of the liquid crystal layer when there is no electric field, or from the azimuth angle φ2 direction and the polar angle θ direction. Incident light angle There be arranged so as to be aligned in-plane direction with high contrast of the liquid crystal panel with respect to the incident light 30 degrees from 10 degrees can solve the problem of the present invention.

(Embodiment of electronic device)
Next, a specific example of an electronic device including any one of the liquid crystal panels 10, 40, and 50 according to the first to third embodiments will be described.

  FIG. 9A is a perspective view showing an example of a mobile phone.

  In FIG. 9A, reference numeral 200 denotes a mobile phone body, and reference numeral 201 denotes a liquid crystal display unit using any one of the liquid crystal panels 10, 40, and 50.

  FIG. 9B is a perspective view illustrating an example of a portable information processing apparatus such as a word processor or a personal computer.

  In FIG. 9B, reference numeral 300 denotes an information processing apparatus, reference numeral 301 denotes an input unit such as a keyboard, reference numeral 303 denotes an information processing apparatus body, and reference numeral 302 denotes a liquid crystal using any one of the liquid crystal panels 10, 40, and 50. The display part is shown.

  FIG. 9C is a perspective view showing an example of a wristwatch type electronic device.

  In FIG. 9C, reference numeral 400 denotes a watch body, and reference numeral 401 denotes a liquid crystal display unit using any one of the liquid crystal panels 10, 40, and 50.

  Each of the electronic devices shown in FIGS. 9A to 9C is provided with a liquid crystal display unit using any one of the liquid crystal panels 10, 40, and 50, and thus there is no display blur. It is excellent in sharp display quality that is high contrast.

“Test Example 1”
A transmittance measurement test was conducted using a directional forward scattering film prepared by a transmission hologram technique.

  Light is incident from the light source of the (halogen) lamp (installed at a position 300 mm away from the directional forward scattering film) at the center of the surface of the rectangular directional forward scattering film (50 × 40) mm installed horizontally. And a light receiving portion (installed at a position 300 mm away from the directional forward scattering film) having a light receiving element made of a CCD on the back side of the directional forward scattering film in a direction facing the front of the incident light from the light source. The polar angle and the azimuth angle of the light source were defined as shown in FIG. 4, and the parallel light transmittance was measured in the light receiving portion with a 2-degree visual field.

  Fig. 3 shows the result of measuring the parallel line transmittance (%) for each polar angle by adjusting the polar angle θ of the light source (incident angle of incident light with respect to the normal of the directional forward scattering film) within a range of ± 60 °. 10 shows. As for the azimuth angle, 0 °, + 30 °, + 60 °, + 90 °, + 180 ° (all in the clockwise direction shown in FIG. 4), −30 °, −60 °, −90 ° (all in FIG. 4). All the data in the counterclockwise direction shown in Fig. 10 were measured and collectively shown in Fig. 10.

  From the results shown in FIG. 10, the measurement results at 0 ° and 180 ° are exactly the same curve, and the relationship between the maximum transmittance Tmax and the minimum transmittance Tmin of parallel-line transmitted light is (Tmax / Tmin) ≈50. : 6≈8.33, indicating a value exceeding 2 that is desired in the present invention.

  Next, FIG. 11 shows the result of a similar transmittance measurement test using another directional forward scattering film created with a transmission hologram, and further using another transmission hologram directional forward scattering film. The result of the same transmittance measurement test is shown in FIG.

  Looking at the characteristics shown in FIG. 11, the relationship between the maximum transmittance Tmax and the minimum transmittance Tmin of parallel-line transmitted light is (Tmax / Tmin) ≈12: 3≈4, which exceeds 2 as desired in the present invention. The value is shown.

  Looking at the characteristics shown in FIG. 12, the relationship between the maximum transmittance Tmax and the minimum transmittance Tmin of parallel-line transmitted light is (Tmax / Tmin) ≈52: 26≈2, which is 2 which is the value desired in the present invention. showed that.

  Also, in any of the example directional forward scattering films shown in FIGS. 10, 11, and 12, it is clear that the maximum and minimum values exist at substantially the same angle in the range of ± 60 °. It was. For example, from the results shown in FIG. 10, the maximum value is a polar angle of −30 °, the minimum value is a polar angle + (23) °, and the maximum value is a polar angle − (20) ° from the result shown in FIG. In this case, the local minimum value is the polar angle + (18) °. From the results shown in FIG. 12, the local maximum value is the polar angle −30 °, and the local minimum value is the polar angle + (25) °.

  Next, in the directional forward scattering film of the example shown in FIG. 10, FIG. 11 and FIG. 12, when φ is ± 90 °, the transmittance is lowest when the polar angle θ is 0 in any example. In other words, it was also found that scattering at the time of incidence is strong (a lot of diffuse transmitted light).

  Moreover, in the directional front scattering film of the example shown in FIG. 10, FIG. 11, FIG. 12, it is also clear that the transmittances under all conditions are all in the range of 2 to 50%.

  Next, when the polar angle θ was fixed and the azimuth angle φ was changed, in other words, when only the directional forward scattering film was rotated in the horizontal plane, the transmittance of the directional forward scattering film was measured. The results are shown in FIG.

  According to the results shown in FIG. 13, under the condition of θ = 0 °, the light is incident in the normal direction of the directional forward scattering film, but shows a substantially constant transmittance, θ = −20 °, − In the case of 40 ° and −60 °, the azimuth angle is in the range of 0 ± 90 °, and the transmittance has a convex maximum curve upward, and in the case of θ = + 20 °, + 40 °, + 60 °, the azimuth angle is 0 ±. In the range of 90 °, the transmittance showed a tendency to show a curve having a minimum convex on the lower side (concave on the upper side). From this, it was clearly shown that the directional forward scattering film used in the present example exhibits maximum and minimum transmittances according to the polar angle and the azimuth angle.

  13 is analyzed, the negative polar angle θ (−20 °, −40 °, −60 °) has an azimuth angle within φ = ± 30 °, that is, φ = −30 ° to In the range of + 30 °, the maximum transmittance is suppressed within 5%, and the azimuth angle φ is within ± 30 ° at the positive polar angle θ (+ 20 °, + 40 °, + 60 °), that is, φ = In the range of −30 ° to + 30 °, the minimum value of the transmittance is suppressed within 5%.

  FIG. 14 shows the relationship between polar angle and transmittance for each azimuth angle in a sample of a liquid crystal device constructed using a conventional isotropic forward scattering film (trade name: IDS-16K, manufactured by Dai Nippon Printing Co., Ltd.). Shows the measurement results. In the test, the same liquid crystal device as in the previous first test example was used, and the directional front scattering film (anisotropic front film) was changed to the isotropic scattering film used this time and measured.

  From the results shown in FIG. 14, the transmittance of parallel-line transmitted light hardly changes at any azimuth, almost overlaps with one curve, and the polar angle is + region with the maximum when the polar angle is 0 °. It is clear that even if it is changed to a region, it changes only about several percent. From this result, it is clear that the effect of the present invention cannot be obtained even when an isotropic front scattering film is used in a liquid crystal device.

"Test Example 2"
Next, the brightness of the reflective color liquid crystal display device using the directional forward scattering film when the polar angle θ1 and the polar angle θ2 of the previous test were changed in various ways was compared in an office under a fluorescent lamp. As the brightness, a reflective color liquid crystal display device using a conventional isotropic forward scattering film (a reflective color liquid crystal display device using an isotropic scattering film used for the measurement shown in FIG. 14) and In comparison, Table 1 below shows the results that were recognized brighter than the conventional reflective color liquid crystal display device, ◯, equivalent ones, and dark ones.

"Table 1"
θ1 (°) -80 -70 -60 -50 -40 -30 -20 -10 0
θ2 (°) 0 0 0 0 0 0 0 0 0
Evaluation result × × × × × △ △ △ ×
θ1 (°) -80 -70 -60 -50 -40 -30 -20 -10 0
θ2 (°) 10 10 10 10 10 10 10 10 10
Evaluation result × × × × △ ○ ○ ○ ×
θ1 (°) -80 -70 -60 -50 -40 -30 -20 -10 0
θ2 (°) 20 20 20 20 20 20 20 20 20
Evaluation result × × × × △ ○ ○ ○ ×
θ1 (°) -80 -70 -60 -50 -40 -30 -20 -10 0
θ2 (°) 30 30 30 30 30 30 30 30 30
Evaluation result × × × × △ ○ ○ ○ ×
θ1 (°) -80 -70 -60 -50 -40 -30 -20 -10 0
θ2 (°) 40 40 40 40 40 40 40 40 20
Evaluation result × × × × × △ △ △ ×
As is clear from the measurement results shown in Table 1, the polar angle θ1 when the parallel-line transmitted light is maximized (when the diffusely transmitted light is minimized) is in the range of −40 ° ≦ θ1 ≦ 0 °, 0 ° If the range is ≦ θ2 ≦ 40 °, the same level of brightness as that of the conventional product can be ensured. It can be seen that a liquid crystal display device having excellent brightness can be obtained.

“Test Example 3”
A directional forward scattering film is prepared in which the parallel line transmittance T (0, 0) in the normal direction of the directional forward scattering film is changed to various values, and the brightness of a liquid crystal display device including the directional forward scattering film is improved. This was compared in offices under fluorescent lighting. The compared conventional product is the same as that used in the previous test example. Table 2 below shows the results that were recognized brighter than the reflective type color liquid crystal display device using the conventional isotropic forward scattering film, ◯ for the equivalent, Δ for the equivalent, and × for the dark.

"Table 2"
T (0.0) 3% 5% 10% 20% 30% 40% 50% 60%
Evaluation result △ ○ ○ ○ ○ ○ △ ×
As is apparent from the results shown in Table 2, if 3% ≦ T (0,0) ≦ 60%, more preferably 5% ≦ T (0,0) ≦ 40%, the actual usage environment It is apparent that a brighter reflective color liquid crystal display device can be provided.

  Next, from the results shown in FIG. 10, FIG. 11, and FIG. 12, when the azimuth angle φ of the directional forward scattering film is defined in the range of φ1 ± 60 ° and φ2 ± 60 °, the parallel transmittance is always at θ1. It is also clear that the maximum (in other words, the minimum of diffuse transmittance) is shown, and the minimum of parallel line transmittance (in other words, the maximum of diffuse transmittance) is shown at θ2.

“Test Example 4”
Next, a number of transmissive hologram directional forward scattering films are prepared, and the brightness of the reflective color display device when the value of (Tmax / Tmin) is adjusted to various values is adjusted to be isotropic with respect to the conventional product. The results compared with a liquid crystal display device using a scattering film are shown in Table 3 below. ◎ if it was recognized more than twice as bright as the conventional liquid crystal display device, ○ if it was recognized brighter than the conventional product, △ if it was equivalent, × if it was dark.

"Table 3"
Tmax / Tmin 10.0 5.0 3.0 2.0 1.8 1.5 1.0
Evaluation result ◎ ◎ ◎ ◎ △ △ △
From the results shown in Table 3, it is clear that recognition was particularly bright when the ratio between the minimum value and maximum value of the parallel line transmittance described above was 2 or more.

"Test Example 5"
In the directional forward scattering film, the azimuth angle when the parallel line transmittance is the minimum value (in other words, the diffuse transmittance is the maximum value) or the parallel line transmittance is the maximum value (in other words, the diffuse transmittance is the minimum value) is φ2 or Assuming φ1, the ratio between the maximum value and the minimum value of the transmitted light characteristics measured by changing the polar angle θ in the range of φ2 ± 60 ° and φ1 ± 60 ° was measured. By changing this ratio, the brightness of the reflection type color liquid crystal display device was compared in an office under a fluorescent lamp. The compared conventional product is the same as that used in the previous test example. Table 4 below shows those that could be recognized brighter than the reflective type color liquid crystal display device using the conventional isotropic forward scattering film, ◯ for the equivalent, Δ for the dark, and × for the dark.

“Table 4”
Maximum / minimum value 5.0 3.5 2.0 1.5 1.5 1.2 1.0
Evaluation result 〇 〇 〇 〇 △ △
From the results shown in Table 4, it was revealed that the maximum / minimum value is preferably 1.5 or more. That is, when the azimuth angle φ of the directional forward scattering film is defined in the range of φ1 ± 60 ° and θ2 ± 60 °, it is clear that the ratio between the minimum value and the maximum value of the parallel line transmittance is 1.5 or more. It is.

"Test Example 6"
In the directional forward scattering film, when the polar angle θ is set to −60 ° ≦ θ ≦ + 60 °, the maximum value and the minimum value of the parallel-line transmittance T are changed to change the brightness of the reflective color liquid crystal display device to fluorescence. Comparisons were made in offices with lights on. The compared conventional product is the same as that used in the previous test example. Table 5 below shows the results that were recognized brighter than the reflection type color liquid crystal display device using the conventional isotropic forward scattering film, ◯ for the equivalent, Δ for the equivalent, and × for the dark.

"Table 5"
Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 1% 1% 1% 1% 1% 1% Evaluation result × × △ △ △ ×
Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 2% 2% 2% 2% 2% 2% Evaluation result × ○ ○ ○ ○ ○ Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 5% 5% 5% 5% 5% 5% Evaluation result △ ○ ○ ○ ○ ○ Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 10% 10% 10% 10% 10% 10% Evaluation result △ ○ ○ ○ ○ △
Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 20% 20% 20% 20% 20% 20% Evaluation result × ○ ○ △ △ ×
Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 30% 30% 30% 30% 30% 30% Evaluation result × △ △ × × ×
Maximum transmittance Tmax 60% 50% 40% 30% 20% 10% Minimum transmittance Tmin 40% 40% 40% 40% 40% 40% Evaluation result × × × × × ×
From the results shown in Table 5, it can be seen that the maximum value / minimum value ≧ 2 is satisfied and the transmittance of 2% or more and 50% or less is necessary.

FIG. 1 is a plan view of a liquid crystal panel according to a first embodiment of the present invention. FIG. 2 is a partial cross-sectional schematic view taken along line AA of the liquid crystal panel shown in FIG. 1. 3 is an enlarged cross-sectional view showing a color filter portion of the liquid crystal panel shown in FIG. FIG. 4 is an explanatory diagram showing a positional relationship among a directional forward scattering film, a light source, a light receiving unit, a polar angle, an azimuth angle, and parallel-line transmitted light. FIG. 5 is an explanatory diagram showing the positional relationship among the directional forward scattering film, the light source, and the light receiving unit. FIG. 6 (A) is an explanatory view showing the relationship between incident light, parallel-line transmitted light, diffused transmitted light, and backscattered light and forward scattered light, and FIG. 6 (B) is a directional forward scattered film. It is explanatory drawing which shows the relationship between an example of the cross-sectional structure of this, and incident light and reflected light. FIG. 7 is a cross-sectional view of a liquid crystal panel according to a second embodiment of the present invention. FIG. 8 is a cross-sectional view of a liquid crystal panel according to a third embodiment of the present invention. FIG. 9A is a perspective view showing a portable phone, FIG. 9B is a perspective view showing an example of a portable information processing apparatus, and FIG. FIG. 3 is a perspective view showing an example of a wristwatch type electronic apparatus. FIG. 10 is a diagram showing a result of measuring a first example of the relationship between the polar angle and the transmittance measured in each example for each azimuth angle. FIG. 11 is a result of measuring the second example of the relationship between the polar angle and the transmittance measured in the example for each azimuth, and the measurement result when the ratio between the minimum value and the maximum value of the parallel line transmittance is 4. FIG. FIG. 12 is a result of measuring the third example of the relationship between the polar angle and the transmittance measured in the example for each azimuth, and the measurement result when the ratio between the minimum value and the maximum value of the parallel line transmittance is 2. FIG. FIG. 13 is a diagram showing the results of measuring the relationship between the azimuth angle and the transmittance measured in each example for each polar angle. FIG. 14 is a diagram showing the result of measuring the relationship between the polar angle and the transmittance measured in the comparative example for each azimuth angle. FIG. 15 is an explanatory diagram of the positional relationship between the azimuth angle φ2 direction in which the parallel-line transmitted light transmitted through the directional forward scattering film shows the minimum transmittance and the major axis direction α of the liquid crystal molecules when no electric field is applied to the STN cell. is there. FIG. 16 is a diagram showing contrast characteristics of the liquid crystal panel of the present embodiment. FIG. 17 is an explanatory diagram of the positional relationship between the azimuth angle φ2 direction in which the parallel-line transmitted light that has passed through the directional forward scattering film shows the minimum transmittance, and the major axis direction α of the liquid crystal molecules when no electric field is applied to the STN cell. is there. FIG. 18 shows a conventional reflective liquid crystal device, FIG. 18 (a) is a schematic sectional view showing an example of a reflective liquid crystal device provided with a scattering film, and FIG. 18 (b) is a reflective type provided with an internal diffuser. It is a section schematic diagram showing an example of a liquid crystal device.

Explanation of symbols

α, β ... major axis direction γ ... in-plane direction θ ... polar angle,
φ ... azimuth,
K ... light source,
J: Light receiving part,
LT: Diffuse transmitted light,
L3 ... Parallel line transmitted light,
Tmax (φ1, θ1) ... maximum transmittance,
Tmin (φ2, θ2) ... minimum transmittance,
10, 40, 50 ... Liquid crystal panel,
15 ... Liquid crystal layer,
15a ... Liquid crystal molecule 15b ... Liquid crystal molecule 17, 28, 28 '... Substrate,
18: Directional forward scattering film,
20 Color filter layer,
23, 35 ... electrode layer,
31 ... reflective layer,
52 ... a transflective layer,
200 ... mobile phone body,
300 ... portable information processing device,
400: A wristwatch type electronic device.

Claims (5)

A pair of substrates, and a nematic liquid crystal layer is sandwiched by the twist angle θt between the pair of substrates, and the reflective layer provided on the liquid crystal layer side of one of the pair of substrates or semi-transmissive reflective layer , it includes a liquid crystal panel provided with the the other of the liquid crystal layer side of the substrate and the directional forward scattering film provided on the opposite side of the pair of substrates,
A liquid crystal device that performs reflection display by light incident on the directional forward scattering film from the outside,
Of the forward scattered light transmitted through the directional forward scattering film , the ratio of the light intensity of the forward scattered light traveling in the direction within ± 2 ° with respect to the traveling direction of the incident light to the incident light intensity is a parallel line transmittance. And the ratio of the light intensity of the forward scattered light diffusing beyond ± 2 ° with respect to the traveling direction of the incident light to the incident light intensity is defined as diffuse transmittance, and the method of the directional forward scattering film When the incident angle of the incident light with respect to the line is defined as the polar angle θn, and the incident light angle in the in-plane direction of the directional forward scattering film is defined as the azimuth angle φm ,
The directional forward scattering film has an incident angle (φ1, θ1) at which the diffuse transmittance is minimum and the parallel line transmitted light is maximized, and an incident angle (φ2, θ2) at which the diffuse transmittance is maximized. Have
The direction facing the directional forward scattering film is the observation direction,
Wherein said diffuse transmission rate becomes maximum polar angle in the directional forward scattering film and the azimuth angle is the lighting direction of the liquid crystal panel, wherein the polar angle and the azimuth angle parallel ray transmittance is maximized and said viewing direction The directional forward scattering film is disposed on the liquid crystal panel,
When the voltage applied between the substrates is released, the major axis direction of the nematic liquid crystal molecules located at the central portion in the thickness direction of the liquid crystal layer is ± 30 ° with respect to the azimuthal direction in which the diffuse transmittance is maximum. The liquid crystal device is characterized in that the liquid crystal molecules are in a range, and the major axis direction of the liquid crystal molecules is a direction in which the liquid crystal molecules respond to an electric field when a voltage is applied between the substrates. The nematic liquid crystal molecules in the liquid crystal layer are set at a twist angle of 60 to 80 degrees, and the nematic liquid crystal molecules located at the center of the liquid crystal layer are aligned on the substrate surface when the voltage applied between the substrates is released. The liquid crystal device according to claim 1 , wherein the liquid crystal device is twisted by 30 to 40 degrees with respect to the nematic liquid crystal molecules. The nematic liquid crystal molecules of the liquid crystal layer are set to a twist angle of 240 to 255 degrees, and the nematic liquid crystal molecules positioned at the center of the liquid crystal layer are aligned on the substrate surface when the voltage applied between the substrates is released. The liquid crystal device according to claim 1 , wherein the liquid crystal device is twisted by 120 to 127.5 degrees with respect to the nematic liquid crystal molecules. Wherein the ratio of the maximum value Tmax and the minimum value Tmin of the parallel ray transmittance, (Tmax / Tmin) liquid crystal device according to any one of claims 1 to 3, characterized in that the ≧ 2 relationship. An electronic apparatus characterized by comprising a display means of the liquid crystal device according to any one of claims 1 to 4.

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