JP4075903B2 - Liquid crystal display panel, liquid crystal display panel substrate and electronic device - Google Patents

Description

  The present invention relates to a liquid crystal display panel, a liquid crystal display panel substrate used in the liquid crystal display panel, and an electronic apparatus using the liquid crystal display panel.

  Conventionally, a so-called transflective liquid crystal display panel that can switch between a reflective display and a transmissive display as necessary has been proposed. As shown in FIG. 13, in this type of liquid crystal display panel, a reflective layer 61 having an opening 611 is provided on the surface of the second substrate 20 that faces the first substrate 10 and sandwiches the liquid crystal 31. . Further, a color filter 62 colored, for example, in red, green, or blue is provided on the observation side (the side on which an observer who views the display image displayed on the liquid crystal display panel) is viewed from the reflective layer 61. Yes. In FIG. 13, illustrations of electrodes for applying a voltage to the liquid crystal 31 and alignment films for defining the alignment state of the liquid crystal 31 are omitted.

  In this configuration, incident light (for example, sunlight or indoor illumination light) from the first substrate 10 side passes through the first substrate 10, the liquid crystal 31, and the color filter 62 as shown as a path R1 in FIG. And reaches the surface of the reflective layer 61. The reflected light on the surface is transmitted through the color filter 62, the liquid crystal 31, and the first substrate 10 and is emitted to the observation side, whereby a reflective display is performed. On the other hand, as shown as a path R <b> 2 in FIG. 13, incident light (for example, irradiation light from the backlight unit) from the second substrate 20 side passes through the opening 611 of the reflective layer 61. Then, this light passes through the color filter 62, the liquid crystal 31, and the first substrate 10 in this order and is emitted to the observation side, whereby transmissive display is performed.

  However, in the conventional transflective liquid crystal display panel, the light visually recognized by the observer in the reflective display is passed through the color filter 62 twice, whereas the observer in the transmissive display. Since the light that is visually recognized passes through the color filter 62 only once, there is a problem that the saturation in the transmissive display is lower than the saturation in the reflective display.

  In the reflective display, the brightness of the display tends to be insufficient due to the small amount of external light incident on the liquid crystal display panel. Therefore, the light transmittance of the color filter 62 is increased for display. It is desirable to ensure a sufficient amount of light to be provided. However, when the light transmittance of the color filter 62 is increased, the lack of saturation at the time of transmissive display becomes more remarkable. Conversely, if the light transmittance of the color filter 62 is lowered in order to eliminate the lack of saturation during transmissive display, the amount of light provided to the reflective display is reduced and sufficient brightness of the display is ensured. Difficult to do.

  The present invention has been made in view of the above-described circumstances, and a liquid crystal display panel capable of ensuring both brightness in reflective display and saturation in transmissive display. It aims at providing the board | substrate for liquid crystal display panels used, and the electronic device using the said liquid crystal display panel.

In order to solve the above problems, in a liquid crystal display panel having a plurality of sub-pixels corresponding to different colors, the first substrate and the second substrate sandwiching the liquid crystal facing each other, and a part of the sub-pixels A reflection layer provided on the second substrate so as to overlap and reflecting incident light from the first substrate side; and provided on the observation side of the reflection layer so as to overlap with the sub-pixel. A color filter that transmits light of a wavelength corresponding to the above, and in a region overlapping the reflective layer in the sub-pixel, the color filter is not provided, A reflection area corresponding to the reflection layer and a translucent area that is an area other than the reflection area and transmits the incident light from the second substrate side to the first substrate side, when viewed in plan, the subpixel. Delimit That together with contact with the opposite pair of sides of the plurality of sides adjacent along the sides, within said sub-pixels, said light-transmitting region is provided so as to face each other across the reflecting region Features.
The substrate for a liquid crystal display panel of the present invention includes a pair of substrates that face each other and sandwich a liquid crystal, and a plurality of subpixels corresponding to different colors, and is provided so as to overlap the subpixels. A substrate for a liquid crystal display panel used in a liquid crystal display panel having a color filter that transmits light having a wavelength corresponding to the color of the sub-pixel and having no color filter in the sub-pixel. The reflection is provided on the one substrate so as to overlap with one of the pair of substrates and a part of the sub-pixel, and reflects incident light from the other substrate side of the pair of substrates. A region in which the color filter is not provided is located in a region of the subpixel that overlaps the reflective layer, and the reflective layer of the subpixels. A corresponding reflective region and a light-transmitting region other than the reflective region that transmits incident light to the other substrate side of the pair of substrates define the sub-pixel when seen in a plan view. The shape of the reflective layer is selected so as to be in contact with and adjacent to a pair of opposing sides of the plurality of sides, and the translucent region sandwiches the reflective region in the sub-pixel. It is provided so that it may oppose.
The liquid crystal display panel substrate of the present invention is a liquid crystal display panel substrate used for a liquid crystal display panel having a pair of substrates that face each other and sandwich a liquid crystal and a plurality of subpixels corresponding to different colors. One of the pair of substrates provided with a reflective layer so as to overlap with a part of the sub-pixel, and provided on the one substrate so as to overlap with the sub-pixel. A color filter that transmits light of a corresponding wavelength, and has a region in which the color filter is not provided in a region that overlaps the reflective layer in the sub-pixel, and the reflection of the sub-pixel is included in the sub-pixel. A reflective region corresponding to the layer and a light-transmitting region that is a region other than the reflective region and transmits incident light to the other substrate side of the pair of substrates, the subpixels are viewed in plan view. Defining A pair of sides facing each other and adjacent to each other along the side, and in the sub-pixel, the translucent region is provided so as to oppose the reflective region. To do.

  According to this liquid crystal display panel, since the opening is provided in the region corresponding to the reflective layer in the color filter, the amount of light provided for the reflective display can be maintained sufficiently, and the transmissive display can be maintained. Sufficient saturation can be maintained. For example, even when the color filter transmittance is lowered to improve the saturation at the time of transmissive display, the amount of light can be reduced by passing a part of the reflected light from the reflective layer through the opening of the color filter. Since the decrease can be suppressed, the brightness in the reflective display is maintained. In the liquid crystal display panel, the color filter may be provided on the first substrate. Of course, the color filter may be provided on the second substrate.

  Furthermore, in the liquid crystal display panel, the area of the color filter opening corresponding to at least one color may be different from the area of the color filter opening corresponding to another color. By so doing, the amount of light that is reflected from the surface of the reflective layer by the reflective layer and emitted to the observation side during reflective display can be arbitrarily set for each sub-pixel of each color. For example, if the area of the opening provided in the color filter is selected according to the transmittance characteristic of each color filter, it is possible to realize good color reproducibility by compensating for variations in the transmittance characteristic for each color. In addition, for example, even when the light emitted from the backlight unit has a variation in spectral characteristics (for example, when the amount of light of each wavelength is different), the area of the opening provided in each color filter depends on the spectral characteristics. If selected, satisfactory variations in color reproducibility can be realized by compensating for such variations. Further, the same effect can be obtained when the area of the reflective layer corresponding to at least one color sub-pixel is different from the area of the reflective layer corresponding to other color sub-pixels.

  In the liquid crystal display panel according to the present invention, among the sub-pixels, the reflective region corresponding to the reflective layer and the region other than the reflective region that receives incident light from the second substrate side It is desirable that the light-transmitting region that is transmitted to the first substrate side is in contact with at least one of the plurality of sides that define the subpixel and is adjacent to the side. In this case, it can be considered that the at least one side of the sub-pixel is a pair of opposing sides among a plurality of sides that define the substantially rectangular sub-pixel. According to this configuration, even when a portion near the periphery of the sub-pixel cannot contribute to display due to a manufacturing error, the areas of both the reflective region and the light-transmitting region are reduced. Thus, it is possible to prevent only one of these areas from being reduced. Therefore, even if a manufacturing error occurs, it is possible to avoid a situation where the area ratio between the reflective area and the light-transmitting area is different from the intended area ratio. As a result, the display quality at the time of reflective display is avoided. And the display quality in the transmissive display can be maintained. For example, in a liquid crystal display panel having a light-shielding layer for shielding light around the sub-pixel, the light-shielding layer overlaps with a portion near the periphery of the sub-pixel due to a manufacturing error, and the portion cannot contribute to display. May occur. Even in such a case, according to the present invention, it is possible to prevent the area ratio between the reflective region and the light transmitting region from differing from the intended (designed) area ratio.

  Furthermore, in the liquid crystal display panel in which an electrode for applying a voltage to the liquid crystal is provided on the second substrate, it is desirable that the reflective layer is formed of a conductive material and is electrically connected to the electrode. . According to this configuration, the resistance value can be suppressed as compared with the case where only the electrode is provided independently (separated from the reflective layer).

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described liquid crystal display panel. As described above, according to the liquid crystal display panel according to the present invention, it is possible to realize a good display quality in both the reflective and transmissive display methods. It is suitable for electronic devices that require switching between transmissive display and high display quality. As such an electronic device, for example, a portable personal computer or a mobile phone can be considered.

  The present invention can also be implemented as a liquid crystal display panel substrate used in a liquid crystal display panel. That is, this liquid crystal display panel may be a substrate for a liquid crystal display panel that is disposed on the back side of the liquid crystal display panel and provided with a reflective layer, or a reflective layer that is disposed on the observation side of the liquid crystal display panel. It is good also as a liquid crystal display panel substrate which does not have.

  That is, the former liquid crystal display panel substrate has a pair of substrates that face each other and sandwich the liquid crystal, and a plurality of subpixels corresponding to different colors, and is provided so as to overlap the subpixels. A substrate for a liquid crystal display panel used in a liquid crystal display panel having a color filter that transmits light having a wavelength corresponding to the color of the sub-pixel and having no color filter in the sub-pixel. The reflection is provided on the one substrate so as to overlap with one of the pair of substrates and a part of the sub-pixel, and reflects incident light from the other substrate side of the pair of substrates. And a region where the color filter is not provided is located in a region of the sub-pixel that overlaps the reflective layer, and of the sub-pixel, A reflection region corresponding to the projecting layer and a translucent region other than the reflection region and transmitting incident light to the other substrate side of the pair of substrates when viewed in plan view, the subpixel. The shape of the reflective layer is selected so as to be in contact with and adjacent to at least one of the plurality of sides that define the region, and in the sub-pixel, the light-transmitting region includes the reflective region. It is provided so that it may oppose on both sides. In this liquid crystal display panel substrate, the color filter may be provided on the one substrate.

  On the other hand, a liquid crystal display panel according to the latter is a liquid crystal display panel substrate used in a liquid crystal display panel having a pair of substrates that face each other and sandwich a liquid crystal and a plurality of sub-pixels corresponding to different colors. Of the pair of substrates, one substrate provided with a reflective layer so as to overlap with a part of the sub-pixel and the one substrate provided so as to overlap with the sub-pixel correspond to the color of the sub-pixel. A color filter that transmits light of a wavelength, and has a region in which the color filter is not provided in a region that overlaps the reflective layer in the sub-pixel. A corresponding reflective region and a light-transmitting region other than the reflective region that transmits incident light to the other substrate side of the pair of substrates define the sub-pixel when seen in a plan view. plural Adjacent along the sides with contact on at least one side out of, within said sub-pixel, the light transmission region is characterized by being provided so as to face each other across the reflective region.

  Embodiments of the present invention will be described below with reference to the drawings. Such an embodiment shows one aspect of the present invention, and does not limit the present invention, and can be arbitrarily changed within the scope of the present invention. In each of the drawings shown below, the scale of each layer and each member is different in order to make each layer and each member recognizable on the drawing.

<A: First Embodiment>
First, an embodiment in which the present invention is applied to a passive matrix type transflective liquid crystal display panel will be described with reference to FIG. As shown in the figure, the liquid crystal display device includes a liquid crystal display panel 1 and a backlight unit 4. The liquid crystal display panel 1 includes a first substrate 10 and a second substrate 20 that are opposed to each other via a sealing material 30, and a region surrounded by the both substrates and the sealing material 30, for example, TN (Twisted). Nematic) type or STN (Super Twisted Nematic) type liquid crystal 31 is sealed. The backlight unit 4 is disposed on the second substrate 20 side of the liquid crystal display panel 1. Hereinafter, as shown in FIG. 1, the side opposite to the backlight unit 4 with respect to the liquid crystal display panel 1 is referred to as “observation side”. That is, the “observation side” means a side on which an observer who views a display image by the liquid crystal display panel 1 is located.

  The backlight unit 4 includes a light source 41 and a light guide plate 42. The light source 41 is configured by, for example, an LED (Light Emitting Diode), a cold cathode tube, or the like, and irradiates the side end surface of the light guide plate 42 with light. The light guide plate 42 is a plate-like member for uniformly guiding the light from the light source 41 incident on the side end surface thereof to the substrate surface of the liquid crystal display panel 1. In addition, a diffusion plate for uniformly diffusing light emitted from the light guide plate 42 to the liquid crystal display panel 1 is attached to a surface of the light guide plate 42 facing the liquid crystal display panel 1. A reflective layer for reflecting light traveling from the light guide plate 42 toward the side opposite to the liquid crystal display panel 1 to the liquid crystal display panel 1 side is attached to the surface on the opposite side (all not shown). Note that the light source 41 is not always lit, and is lit according to an instruction from the user or a detection signal from the sensor when used in an environment where there is not enough external light.

  On the other hand, the first substrate 10 and the second substrate 20 of the liquid crystal display panel 1 are plate-like members having light transmissivity, such as glass, quartz, and plastic. Among them, a retardation plate 101 for compensating for interference colors and a polarizing plate 102 for polarizing incident light are attached to the outer surface (opposite to the liquid crystal 31) of the first substrate 10. . Similarly, a retardation plate 201 and a polarizing plate 202 are attached to the outer surface (opposite side to the liquid crystal 31) of the second substrate 20.

  On the surface of the first substrate 10, a plurality of common electrodes 14 are provided. Here, FIG. 2 is a plan view showing a configuration of some elements constituting the liquid crystal display panel 1. A sectional view taken along line AA ′ in FIG. 2 corresponds to FIG. As shown in FIGS. 1 and 2, each common electrode 14 is a strip-like electrode formed of a transparent conductive material such as ITO (Indium Tin Oxide), and extends in the X direction shown in the drawings.

  On the other hand, a plurality of segment electrodes 22 are provided on the surface of the second substrate 20. Each segment electrode 22 is a strip-like electrode formed of a transparent conductive material such as ITO like the common electrode 14, and as shown in FIGS. 1 and 2, a direction intersecting the common electrode 14 (that is, in the figure). (Y direction). As shown in FIG. 1, the surface of the first substrate 10 on which the common electrode 14 is formed and the surface of the second substrate 20 on which the segment electrode 22 is formed are covered with alignment films 15 and 23, respectively. The alignment films 15 and 23 are organic thin films formed of polyimide or the like, for example, and are subjected to a rubbing process for defining the alignment state of the liquid crystal 31 when no voltage is applied.

  The alignment direction of the liquid crystal 31 sandwiched between the first substrate 10 and the second substrate 20 changes according to the voltage applied between the common electrode 14 and the segment electrode 22. Hereinafter, as shown in the lower right portion in FIG. 2, the region 5 where the common electrode 14 and the segment electrode 22 face each other is referred to as a “sub-pixel”. That is, the sub-pixel 5 can be said to be a minimum unit of a region where the alignment direction of the liquid crystal 31 changes according to the application of voltage. As shown in FIG. 2, the plurality of sub-pixels 5 are arranged in a matrix form in the X direction and the Y direction, and each corresponds to one of red (R), green (G), and blue (B) To do. A set of three sub-pixels 5R, 5G, and 5B corresponding to these three colors constitutes one pixel (dot) corresponding to the minimum unit of the display image.

  Next, as shown in FIG. 1, a light shielding layer 11, a color filter 12, and an overcoat layer 13 are formed on the inner surface (liquid crystal 31 side) surface of the first substrate 10. Among these, the overcoat layer 13 is formed of, for example, an acrylic or epoxy resin material, and plays a role of flattening a step between the light shielding layer 11 and the color filter 12. The common electrode 14 described above is formed on the surface of the overcoat layer 13.

  The light shielding layer 11 is formed in a lattice shape so as to cover the gap between the sub-pixels 5 arranged in a matrix (that is, a region other than the region where the common electrode 14 and the segment electrode 22 face each other). It plays the role of shielding the surroundings. The light shielding layer 11 is formed of, for example, a black resin material in which carbon black is dispersed or a metal such as chromium (Cr).

  Next, the color filter 12 (12R, 12G, and 12B) is a resin layer formed corresponding to each sub-pixel 5, and a color corresponding to the color of the sub-pixel 5 by a dye or pigment, that is, red (R) , Green (G) and blue (B), respectively. Therefore, light having a wavelength corresponding to the color of each color filter 12 out of the light transmitted through the liquid crystal 31 toward the first substrate 10 is selectively emitted to the observation side. Further, the color filter 12 is provided with an opening 121 corresponding to the vicinity of the center of each sub-pixel 5 as shown in FIG. 1, which will be described later. In the present embodiment, a case where a configuration (so-called stripe arrangement) in which the color filters 12 of the same color are arranged over a plurality of sub-pixels 5 arranged in the Y direction is exemplified.

  FIG. 3 is a graph showing the transmittance characteristics of the color filter 12 used in this embodiment. In FIG. 3, the wavelength of the incident light to the color filter 12 is shown on the horizontal axis, and the transmittance (ratio of the output light quantity with respect to the incident light quantity) is shown on the vertical axis. As shown in the figure, the color filter 12R exhibits a high transmittance with respect to light having a wavelength of about 600 nm or more corresponding to red, and the color filter 12G has a wavelength of about 500 to 600 nm corresponding to green. The color filter 12B exhibits high transmittance with respect to light having a wavelength of about 400 to 500 nm corresponding to blue. When comparing the maximum transmittance of each color filter 12 in the graph of FIG. 3, the maximum transmittance (approximately 0.92) of the red color filter 12R is the largest, and then the maximum transmittance (approximately approximately) of the blue color filter 12B. 0.89), it can be seen that the green color filter 12G decreases in the order of the maximum transmittance (about 0.84). That is, when the same amount of light is applied to each color filter 12, the amount of light emitted from the green color filter 12G is less than the amount of light emitted from the red color filter 12R and the blue color filter 12B.

  On the other hand, as shown in FIGS. 1 and 2, a plurality of reflective layers 21 are provided on the inner surface (the liquid crystal 31 side) surface of the second substrate 20. Each reflective layer 21 is a layer for reflecting incident light from the first substrate 10 side. For example, the reflective layer 21 has a light reflectivity formed by a single metal such as aluminum or silver or an alloy containing these as main components. It is a thin film. The reflective layer 21 in the present embodiment is formed of an alloy containing silver as a main component and containing palladium (Pd) and copper (Cu). Further, the inner surface of the second substrate 20 is roughened to form a scattering structure (unevenness) on the surface of the reflective layer 21, but the illustration is omitted. Instead of a configuration in which a scattering structure is formed on the surface of the reflective layer 21, a so-called forward scattering method in which the viewing-side polarizing plate 102 has scattering characteristics may be employed.

  Here, FIG. 4 is a diagram showing the positional relationship between each reflective layer 21 and the segment electrode 22, and is a cross section taken along line BB ′ in FIG. 2 (that is, a cross section orthogonal to the extending direction of the segment electrode 22. FIG. As shown in the figure, the reflective layer 21 is covered with the segment electrode 22 over the entire periphery of the cross section orthogonal to the segment electrode 22. More specifically, as shown in FIG. 4, the first layer 221 constituting a part of the segment electrode 22 is formed on the inner surface of the second substrate 20, and the width of the first layer 221 in the width direction is increased. A reflective layer 21 is formed so as to cover a part. Further, the second layer 222 constituting the segment electrode 22 is formed so as to cover the reflective layer 21 from the surface parallel to the second substrate 20 in the reflective layer 21 to the peripheral edge (edge) in the width direction. With this configuration, the segment electrode 22 and the reflective layer 21 are electrically connected. While the ITO constituting the segment electrode 22 has a relatively high resistance value, the APC alloy constituting the reflective layer 21 has a low resistance value. For this reason, as shown in FIG. 4, the wiring resistance can be kept low by bringing the segment electrode 22 and the reflective layer 21 into contact with each other.

  On the other hand, as shown in FIG. 2, focusing on a plane parallel to the substrate surface of the second substrate 20, each of the plurality of reflective layers 21 is provided so as to overlap a part of each sub-pixel 5. Further, each reflection layer is configured such that the entire periphery thereof is located in the sub-pixel 5. In other words, the reflective layers 21 are provided in the sub-pixels 5 so as to be separated from each other in the form of islands.

  A region of the sub-pixel 5 that overlaps with the reflective layer 21 (hereinafter referred to as “reflective region 51”) functions as a region for reflecting light from the first substrate 10 side and performing reflective display. That is, when performing a reflective display, external light such as sunlight and room illumination light incident on the liquid crystal display panel 1 from the observation side passes through the polarizing plate 102 and the retardation plate 101 to be in a predetermined polarization state. After that, the light reaches the reflection layer 21 through the path of the first substrate 10 → the color filter 12 → the common electrode 14 → the liquid crystal 31 → the segment electrode 22, and is reflected on the surface thereof, and the path that has just come is traced in reverse. At this time, since the alignment state of the liquid crystal 31 changes according to the voltage difference between the common electrode 14 and the segment electrode 22, the reflected light in the reflective region 51 passes through the polarizing plate 102 and is visually recognized by the observer. The amount of light is controlled for each sub-pixel 5.

  On the other hand, a region other than the reflective region 51 in the sub-pixel 5, that is, a region other than the region covered by the reflective layer 21 in the sub-pixel 5 (hereinafter referred to as “translucent region”) It functions as a region for transmitting light incident on the two substrates 20 and performing transmissive display. That is, when transmissive display is performed by turning on the light source 41 of the backlight unit 4, the irradiation light of the backlight unit 4 becomes a predetermined polarization state by passing through the polarizing plate 202 and the phase difference plate 201. Thereafter, the light is emitted to the observation side through a path of the second substrate 20 → (translucent region 52 →) segment electrode 22 → liquid crystal 31 → common electrode 14 → color filter 12 → first substrate 10. Also in this transmissive display, since the alignment state of the liquid crystal 31 changes according to the voltage difference between the common electrode 14 and the segment electrode 22, the light transmitted through the light transmitting region 52 passes through the polarizing plate 102. The amount of light visually recognized by the observer is controlled for each sub-pixel 5.

  Next, with reference to FIG. 5, a more detailed configuration of the reflective layer 21 and the color filter 12 will be described. In FIG. 5, only the sub-pixels 5 for three colors constituting one pixel are shown.

  As described above, each of the sub-pixels 5 corresponds to the reflective layer 21 and reflects the incident light from the first substrate 10 side, and corresponds to the region other than the reflective layer 21 on the second substrate 20 side. Light transmission region 52 that transmits the incident light from the first substrate 10 side. As shown in FIG. 5, the color filter 12 of each color is provided with an opening 121 in a region corresponding to the reflective region 51 in the sub-pixel 5. The opening 121 is a portion where the color filter 12 is not provided, and the transparent overcoat layer 13 covering the color filter 12 and the light shielding layer 11 enters the opening 121. In such a configuration, among the light reflected from the surface of the reflective layer 21 when the reflective display is performed, the amount of light transmitted through the color filter 12 (portion other than the opening 121) is reduced by the action of the color filter 12. On the other hand, the light emitted through the opening 121 of the color filter 12 to the first substrate 10 side is only transmitted through the transparent overcoat layer 13, so that the amount of light is hardly reduced. Therefore, for example, even when the light transmittance of the color filter 12 is increased in order to ensure saturation in transmissive display (that is, when the amount of pigment or dye dispersed in the color filter 12 is increased). Therefore, a bright display can be performed with a sufficient amount of light provided for the reflective display. As described above, according to the present embodiment, it is possible to ensure both the brightness in the reflective display and the saturation in the transmissive display.

  Next, in the present embodiment, as shown in FIG. 5, the area of the opening 121 provided in the color filter 12 is different for each color filter 12. That is, the area of the opening 121 provided in the green color filter 12G is larger than the area of the opening 121 provided in the red color filter 12R and the blue color filter 12B. Here, as described above with reference to FIG. 3, the maximum transmittance of the green color filter 12G is lower than the maximum transmittance of the red color filter 12R and the blue color filter 12B. That is, the area of the opening 121 of each color filter 12 is selected according to the difference in transmittance characteristics of each color filter 12.

  Furthermore, as shown in FIGS. 2 and 5, the area ratio between the reflective region 51 and the light-transmitting region 52 is also different depending on the difference in the transmittance characteristics of the color filters 12. In other words, the area of the reflective layer 21 corresponding to each sub-pixel 5 differs depending on the color of the sub-pixel 5. Specifically, the area of the reflective region 51 (or reflective layer 21) corresponding to the green sub-pixel 5G is larger than the area of the reflective region 51 (or reflective layer 21) corresponding to the red and blue sub-pixels 5R and 5B. Is also getting bigger.

  In this way, by making the area of the opening 121 of the color filter 12 and the area of the reflective layer 21 different for each sub-pixel 5 of each color, the difference in the transmittance characteristics of each color filter 12 is compensated and good display quality is achieved. There is an advantage that can be secured. Hereinafter, this effect will be described in detail.

  First, attention is paid to the area of the opening 121 provided in each color filter 12. Since the maximum transmittance of the green color filter 12G is lower than the maximum transmittance of the color filters 12 of the other colors, if the openings 121 having the same area are provided for all the color filters 12, the green color filter 12G The amount of light transmitted through the filter 12G is less than the amount of light transmitted through the red and blue color filters 12R and 12B. Accordingly, the amount of light visually recognized by the observer for each color of red, green, and blue in the reflective display varies, and as a result, it may be difficult to achieve good color reproducibility. On the other hand, in the present embodiment, the green color filter 12G having a low transmittance is provided with the opening 121 having a larger area than the other color filters 12R and 12B. The balance of the amount of light visually recognized by the observer can be maintained for each of the green and blue colors.

  Next, attention is paid to the area of the reflective layer 21 of each sub-pixel 5. Since the maximum transmittance of the green color filter 12G is lower than the maximum transmittance of the color filters 12 of other colors, if the areas of the reflective regions 51 are made equal for all the sub-pixels 5 of the color, the green sub-pixel 5 The amount of light reflected on the surface of the reflective layer 21 corresponding to and emitted to the observation side is smaller than the amount of light reflected on the surface of the reflective layer 21 corresponding to the sub-pixel 5 of another color and emitted to the observation side. Thus, the amount of light of each color visually recognized by the observer varies. On the other hand, in the present embodiment, the area of the reflective layer 21 corresponding to the green sub-pixel 5G is larger than the areas of the reflective layers 21 of the other sub-pixels 5R and 5B. A sufficient amount of light reflected by the surface of the reflective layer 21 corresponding to 5G and emitted to the observation side can be secured.

  As described above, according to this embodiment, even when there is a variation in the transmittance characteristics of the color filters 12 of the respective colors, good color reproducibility can be realized by compensating for this.

  In FIG. 5 again, when attention is paid to the positional relationship between each sub-pixel 5 and the reflection region 51 and the light-transmitting region 52 in the sub-pixel 5, in the present embodiment, both the reflection region 51 and the light-transmitting region 52 are The four sides defining the sub-pixel 5 (that is, the four sides constituting the periphery of the sub-pixel 5) are in contact with a pair of sides extending in the Y direction, and each region is adjacent to the side. It is like that. That is, when each of the two long sides of the substantially rectangular sub-pixel 5 is traced from one end of the side toward the other end, the light-transmitting region 52, the reflecting region 51, and the light-transmitting along the side. Each region is adjacent in the order of the region 52. In other words, as shown in FIG. 5, when a straight line L that is in contact with the long side of the sub-pixel 5 and is parallel to the side is assumed in the sub-pixel 5, the straight line L is reflected by the reflective region 51 and the translucent region. 52 is passed through.

  Thus, in the present embodiment, the reflection region 51 and the light transmission region 52 corresponding to one subpixel 5 are adjacent to each other along the peripheral edge of the subpixel 5. As for the area ratio of the reflection region 51 and the light transmission region 52 in FIG. The details are as follows.

  As a configuration for including the reflective region 51 and the translucent region 52 in one subpixel 5, for example, the configuration shown in FIG. That is, the reflective layer 21 is configured such that the peripheral edge of the reflective layer 21 corresponding to each sub-pixel 5 does not contact the peripheral edge of the sub-pixel 5, in other words, only the translucent region 52 contacts the peripheral edge of each sub-pixel 5. Is formed.

Here, in the process of manufacturing the liquid crystal display panel 1 having such a configuration, attention is focused on the process of bonding the second substrate 20 on which the reflective layer 21 is formed and the first substrate 10 on which the light shielding layer 11 is formed. In this step, the substrates are generally bonded together while relatively aligning the substrates. At this time, if it is assumed that the relative positions of the two substrates in the X direction are shifted due to, for example, reasons for manufacturing technology, as shown in FIG. Is partially covered with the light shielding layer 11. Since the portion covered with the light shielding layer 11 cannot contribute to the display in this way, the area of the translucent region 52 in the sub-pixel 5 is set when the light shielding layer 11 is appropriately arranged (that is, FIG. 6). Compared with (a)). On the other hand, since the reflective region 51 does not contact the periphery of the region, the reflective region 51 is not covered with the light shielding layer 11 even when the substrate is displaced. That is, the area of the reflective region 51 occupying the sub-pixel 5 is not different from the case shown in FIG. As described above, in the configuration illustrated in FIG. 6, the area of the light-transmitting region 52 decreases while the area of the reflective region 51 does not change due to the substrate bonding error. The area ratio with the region 52 is different from the intended area ratio. As a result, the brightness varies depending on the display method, for example, the brightness of the transmissive display becomes darker than that of the reflective display.

  On the other hand, in the present embodiment, the reflective region 51 and the translucent region 52 are adjacent to each other in the vicinity of a plurality of sides that define one subpixel 5. Therefore, when the relative positions of the first substrate 10 and the second substrate 20 are shifted in the X direction from the appropriate position (designed position) shown in FIG. As shown, the area of the reflective region 51 decreases with the area of the light transmitting region 52. That is, according to the present embodiment, even if the relative positions of the reflective layer 21 and the light shielding layer 11 are shifted, only one area of the light transmitting region 52 or the reflective region 51 is reduced. Therefore, it is possible to prevent the area ratio between the reflective region 51 and the translucent region 52 from deviating from an intended value.

<B: Second Embodiment>
Next, a liquid crystal display panel according to a second embodiment of the present invention will be described.
In the said 1st Embodiment, the structure by which the light shielding layer 11, the color filter 12, and the overcoat layer 13 were provided on the 1st board | substrate 10 located in the observation side was illustrated. In contrast, in the present embodiment, these elements are provided on the second substrate 20.

  FIG. 8 is a cross-sectional view showing the configuration of the liquid crystal display panel according to the present embodiment, and FIG. 9 is a plan view and a cross-sectional view showing the positional relationship among sub-pixels, color filters, and reflective layers in the liquid crystal display panel. . Of the components shown in FIGS. 8 and 9, those common to the components of the liquid crystal display panel 1 according to the first embodiment are given the same reference numerals.

  As shown in FIGS. 8 and 9, a plurality of reflective layers 21 corresponding to the sub-pixels 5 are formed on the surface of the second substrate 20. These reflective layers 21 are the same as those shown in the first embodiment. That is, as shown in FIG. 9, each of the reflective layers 21 is formed inside the peripheral edge of the sub-pixel 5, and the reflective area 51 and the translucent area 52 are adjacent to each other along the peripheral edge of each sub-pixel 5. Thus, the shape is selected and the area of the reflective layer 21 corresponding to the green sub-pixel 5G is larger than the area of the reflective layer 21 corresponding to the sub-pixels 5R and 5B of other colors.

  Then, on the surface of the second substrate 20 on which the plurality of reflective layers 21 are formed, the light shielding layer 11 that overlaps the gaps between the sub-pixels 5 and the color filters 12 (12R, 12G, 12B). As shown in FIG. 9, an opening 121 is provided in a region corresponding to the reflection region 51 in each color filter 12. Similar to the first embodiment, the area of each opening 121 is different for each sub-pixel 5 of each color. That is, as shown in FIG. 9, the area of the opening 121 corresponding to the green sub-pixel 5G is larger than the area of the opening 121 corresponding to the red and blue sub-pixels 5R and 5B.

  Further, the surface of the second substrate 20 provided with the reflective layer 21, the light shielding layer 11, and the color filter 12 is covered with the overcoat layer 13, and the segment electrode 22 is formed on the surface of the overcoat layer 13. . Unlike the configuration shown in FIG. 4 (configuration consisting of the first layer 221 and the second layer 222), the segment electrode 22 is made of a single layer of transparent conductive material. The surface of the overcoat layer 13 provided with the segment electrodes 22 is covered with an alignment film 23.

  On the other hand, as shown in FIG. 8, a common electrode 14 is formed on the inner surface of the first substrate 10, and the common electrode 14 is covered with an alignment film 15. In the cross-sectional view of FIG. 9, illustration of each element on the first substrate 10 is omitted.

  As described above, the same effect as that shown in the first embodiment can be obtained also by the configuration in which the light shielding layer 11 and the color filter 12 are provided on the second substrate 20. That is, as shown in the first and second embodiments, it is determined whether the color filter 12 is provided on either the first substrate 10 located on the observation side or the second substrate 20 located on the back side. Regardless, the present invention can be applied. However, since the light shielding layer 11 and the color filter 12 are generally formed with relatively high accuracy using photolithography, etching technique, or the like, the case where the light shielding layer 11 is formed on the first substrate 10 and In comparison, it can be said that a situation in which a relative position shift between the reflective layer 21 and the light shielding layer 11 is unlikely to occur. Considering this situation, the advantage that the error of the area ratio between the reflection region 51 and the light transmission region 52 described with reference to FIGS. 6 and 7 can be suppressed is that the light shielding layer 11 (and the color filter 12) is the first. It can be said that it appears particularly remarkably when it is formed on one substrate 10.

<C: Modification>
Although one embodiment of the present invention has been described above, the above embodiment is merely an example, and various modifications can be made to the above embodiment without departing from the spirit of the present invention. As modifications, for example, the following can be considered.

<C-1: Modification 1>
In each of the embodiments described above, the area of the reflective layer 21 corresponding to the green sub-pixel 5G and the area of the opening 121 of the color filter 12G are set to red to compensate for the difference in transmittance characteristics of the color filters 12 of the respective colors. The areas corresponding to the sub-pixel 5G and the blue sub-pixel 5B are made different from each other. However, the areas may be made different for red, green, and blue. In each of the above embodiments, the area of the reflective layer 21 corresponding to the sub-pixel of each color and the area of the opening 121 of the color filter 12 are made different according to the transmittance characteristics of the color filter 12. Depending on the spectral characteristics of the irradiation light from the backlight unit, it may be varied. That is, for example, when there is a variation in the spectral characteristics of the light emitted from the backlight unit 4 such that the amount of light of the wavelength corresponding to blue is less than the amount of light of the wavelength corresponding to green and red, the blue sub-pixel By making the area of the reflective layer 21 corresponding to 5B smaller than the area of the reflective layer 21 corresponding to the sub-pixels 5 of other colors, a wide light-transmitting region 52 of the sub-pixel 5B may be secured. . Thus, the elements for determining the area of the reflective layer 21 corresponding to each sub-pixel 5 and the area of the opening 121 of the color filter 12 are not limited to the transmittance characteristics of the color filter 12. On the other hand, in the present invention, the area of the reflective layer 21 of each sub-pixel 5 and the area of the opening 121 of the color filter 12 are not necessarily different.

<C-2: Modification 2>
In the first embodiment, as illustrated in FIG. 4, the configuration in which the reflective layer 21 is brought into contact with the segment electrode 22 is illustrated, but it is not always necessary to bring them into contact with each other. That is, as shown in FIG. 10, the surface of the second substrate 20 provided with the reflective layer 21 is covered with an insulating layer 25 made of a resin material or the like, and a single layer of a transparent conductive film is formed on the surface of the insulating layer 25. It is good also as a structure which provided the segment electrode 22 which consists of.

<C-3: Modification 3>
In the above embodiment, a passive matrix type liquid crystal display panel having no switching element is exemplified, but a two-terminal switching element represented by TFD (Thin Film Diode) or a TFT (Thin Film Transistor) is represented. The present invention can also be applied to an active matrix liquid crystal display panel including a three-terminal switching element, as in the above embodiment. Further, in each of the above-described embodiments, the case where the stripe arrangement in which the color filters 12 of the same color are arranged in a row is illustrated. However, as the arrangement of the color filters 12, a mosaic arrangement or a delta arrangement is also used. It can also be adopted.

<D: Electronic equipment>
Next, electronic devices using the liquid crystal display panel according to the present invention will be described.

<D-1: Mobile computer>
First, an example in which the liquid crystal display panel according to the present invention is applied to a display unit of a portable personal computer (so-called notebook personal computer) will be described. FIG. 11 is a perspective view showing the configuration of the personal computer. As shown in the figure, the personal computer 91 includes a main body 912 having a keyboard 911 and a display 913 to which the liquid crystal display panel according to the present invention is applied.

<D-2: Mobile phone>
Next, an example in which the liquid crystal display panel according to the present invention is applied to a display unit of a mobile phone will be described. FIG. 12 is a perspective view showing the configuration of this mobile phone. As shown in the figure, the mobile phone 92 includes a plurality of operation buttons 921, an earpiece 922, a mouthpiece 923, and a display unit 924 to which the liquid crystal display panel according to the present invention is applied.

In addition to the personal computer shown in FIG. 11 and the mobile phone shown in FIG. 12, electronic devices to which the liquid crystal display panel according to the present invention can be applied include a liquid crystal television, a viewfinder type, and a monitor direct view type. Examples include a video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, a word processor, a workstation, a video phone, a POS terminal, and a digital still camera.
According to the liquid crystal display panel of the present invention, it is possible to maintain both the brightness in the reflective display and the saturation in the transmissive display, and maintain good display quality in both display methods. Therefore, it is particularly suitable for an electronic device that requires a good display quality by both a reflection type and a transmission type.

  As described above, according to the present invention, it is possible to ensure both the brightness in the reflective display and the saturation in the transmissive display.

It is sectional drawing which shows the structure of the liquid crystal display panel which concerns on 1st Embodiment of this invention. It is a top view which shows the relationship between the common electrode in the same liquid crystal display panel, a segment electrode, and a reflection layer. It is a graph which shows the transmittance | permeability characteristic of the color filter in the liquid crystal display panel. It is sectional drawing which shows the relationship between the segment electrode and reflective layer in the liquid crystal display panel. It is the top view and sectional drawing which show the positional relationship of the sub pixel in the same liquid crystal display panel, a color filter, and a reflection layer. It is a figure which shows the contrast for demonstrating the effect of the embodiment. It is a figure for demonstrating the effect of the same embodiment. It is sectional drawing which shows the structure of the liquid crystal display panel which concerns on 2nd Embodiment of this invention. It is the top view and sectional drawing which show the positional relationship of the sub pixel in the same liquid crystal display panel, a color filter, and a reflection layer. It is sectional drawing which shows the structure of the liquid crystal display panel which concerns on the modification of this invention. It is a perspective view which shows the structure of the personal computer which is an example of the electronic device to which the liquid crystal display panel which concerns on this invention is applied. It is a perspective view which shows the structure of the mobile telephone which is an example of the electronic device to which the liquid crystal display panel which concerns on this invention is applied. It is sectional drawing which shows the structure of the conventional transflective liquid crystal display panel.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1 '... Liquid crystal display panel, 10 ... 1st board | substrate, 11 ... Light-shielding layer, 12 (12R, 12G, 12B) ... Color filter, 121 ... Opening part, 13 ... Overcoat layer, 14 ... Common electrode, 15, 23 ... Alignment film, 20 ... Second substrate, 21 ... Reflective layer, 22 ... Segment electrode, 221 ... First layer, 222 ... Second layer, 30 ... Seal Material: 31 ... Liquid crystal, 101, 201 ... Retardation plate, 102, 202 ... Polarizing plate, 4 ... Backlight unit, 41 ... Light source, 42 ... Light guide plate, 5 (5R, 5G, 5B) …… Sub-pixel, 51 …… Reflection area, 52 …… Translucent area, 91 …… Personal computer (electronic device), 92 携 帯 Mobile phone (electronic device).

Claims (10)

In a liquid crystal display panel comprising a first substrate and a second substrate that sandwich a liquid crystal facing each other and having a plurality of sub-pixels corresponding to different colors,
A reflective layer provided on the second substrate so as to overlap with a part of the sub-pixel and reflecting incident light from the first substrate;
A color filter that is provided so as to overlap the subpixel on the observation side of the reflective layer, and transmits light having a wavelength corresponding to the color of the subpixel;
In a region overlapping with the reflective layer in the sub-pixel, has a region where the color filter is not provided,
Among the sub-pixels, a reflective area corresponding to the reflective layer and a translucent area that is an area other than the reflective area and transmits incident light from the second substrate side to the first substrate side are planar. In contact with a pair of opposing sides of the plurality of sides that define the subpixel, and adjacent to the side,
In the sub-pixel, the light-transmitting region is provided so as to face each other with the reflection region interposed therebetween.   The liquid crystal display panel according to claim 1, wherein the color filter is provided on the first substrate. The area of the color filter corresponding to at least one color where the color filter is not provided is different from the area of the color filter corresponding to another color where the color filter is not provided. The liquid crystal display panel according to claim 1.   2. The liquid crystal display panel according to claim 1, wherein the area of the reflective layer corresponding to at least one subpixel is different from the area of the reflective layer corresponding to another color subpixel.   The liquid crystal display panel according to claim 1, further comprising a light shielding layer that shields light around the subpixel.   The electrode for applying a voltage to the liquid crystal provided on the second substrate is provided, and the reflective layer has conductivity and is electrically connected to the electrode. Item 2. A liquid crystal display panel according to item 1.   An electronic apparatus comprising the liquid crystal display panel according to claim 1. Light having a wavelength corresponding to the color of the sub-pixel, which has a pair of substrates opposed to each other and a plurality of sub-pixels corresponding to different colors, and is provided so as to overlap with the sub-pixels A substrate for a liquid crystal display panel used in a liquid crystal display panel having a region in which the color filter is not provided in the sub-pixel.
One of the pair of substrates;
A reflective layer provided on the one substrate so as to overlap with a part of the sub-pixel, and reflecting incident light from the other substrate side of the pair of substrates;
A region where the color filter is not provided is located in a region of the sub-pixel that overlaps the reflective layer; and
Among the sub-pixels, a reflection region corresponding to the reflection layer and a light-transmitting region that is a region other than the reflection region and transmits incident light to the other substrate side of the pair of substrates are planar. Specifically, the shape of the reflective layer is selected so as to be in contact with and adjacent to a pair of opposing sides of the plurality of sides defining the subpixel,
A substrate for a liquid crystal display panel, wherein the translucent region is provided in the sub-pixel so as to face each other with the reflective region interposed therebetween. The liquid crystal display panel substrate according to claim 8 , wherein the color filter is provided on the one substrate. In a liquid crystal display panel substrate used for a liquid crystal display panel having a plurality of sub-pixels corresponding to different colors and a pair of substrates opposed to each other and holding a liquid crystal,
Of the pair of substrates, one substrate provided with a reflective layer so as to overlap with a part of the sub-pixels;
A color filter provided on the one substrate so as to overlap with the sub-pixel and transmitting light having a wavelength corresponding to the color of the sub-pixel;
In a region overlapping with the reflective layer in the sub-pixel, has a region where the color filter is not provided,
Among the sub-pixels, a reflection region corresponding to the reflection layer and a light-transmitting region that is a region other than the reflection region and transmits incident light to the other substrate side of the pair of substrates are planar. In contact with a pair of opposing sides of the plurality of sides that define the subpixel, and adjacent to the side,
A substrate for a liquid crystal display panel, wherein the translucent region is provided in the sub-pixel so as to face each other with the reflective region interposed therebetween.

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