JP4125198B2 - Liquid crystal display element - Google Patents

Description

  The present invention relates to a liquid crystal display element used in a display device such as an information display of an electronic information device, and particularly relates to a liquid crystal display element having a backlight.

  In recent years, in the field of portable information devices such as mobile phones and PDAs, which are in increasing demand, liquid crystal display elements having excellent characteristics of light weight, thinness, and low power consumption are suitably used as information display displays. . For example, a transmissive liquid crystal display element applied to a display unit of a notebook personal computer or the like includes a liquid crystal cell formed by a pair of substrates sandwiching liquid crystal, and a backlight provided on the back surface of the liquid crystal cell. In addition, transmissive display is performed using light emitted from the backlight. Although this transmissive liquid crystal display element is capable of bright display, there is a problem that the power consumed by the backlight is enormous. When applied to a device operated by a battery such as a portable information device, Especially, it becomes an important issue.

  On the other hand, the reflection type liquid crystal display element is configured to display by reflecting external light by providing a light reflection layer on the substrate of the liquid crystal cell. The reflective liquid crystal display element can display well in a sufficiently bright place, but it is difficult to see the display in a dark place.

  In order to solve this problem, a front light is installed on the front side (observer side) of the reflective liquid crystal display element, and light is radiated from the front light in a dark place to assist light for display. It is known. However, since the observer must always view the display through the front light, it is inevitable that the display performance deteriorates due to a decrease in contrast due to interface reflection on the light guide plate of the front light.

  In contrast, a transflective type (transflective type) comprising a backlight provided on the back side of the liquid crystal cell and a transflective plate provided on the substrate on the backlight side among the substrates sandwiching the liquid crystal A liquid crystal display element is known. The transflective plate includes a light reflecting layer and an opening that is formed in the light reflecting layer and transmits light emitted from the backlight.

  The transflective liquid crystal display element is configured to perform reflective display using external light in a bright place, and to perform transmissive display using a backlight in a dark place. Therefore, good display is possible regardless of the surrounding brightness, and since there is no member that deteriorates display performance like the front light and the appearance is good, the portable information device such as a mobile phone or PDA has a good appearance. Widely applied as a display unit.

  However, the transflective liquid crystal display element, like the transmissive liquid crystal display element, has a problem that power consumption is large because it has a backlight, and the light from the backlight is used more efficiently. Therefore, it has been desired to reduce power consumption.

  Therefore, it is conceivable to increase the light use efficiency of the backlight by increasing the aperture ratio, which is the area ratio of the aperture of the transflective plate to the area of the pixel. However, this method has a problem that the area of the light reflection layer that reflects external light is reduced and the brightness of the reflected light is lowered, so that the display quality in a bright place is lowered.

  Therefore, for the purpose of improving the light utilization efficiency of both the backlight and the outside light, a lens array is provided between the liquid crystal cell and the backlight without increasing the opening, and the lens array allows the light from the backlight. It is known to concentrate irradiated light on an opening (see, for example, Patent Document 1).

  As a result, the light from the backlight can be effectively used for display without being blocked by the light reflecting layer, so that brighter transmissive display is possible. In addition, when displaying with the same brightness as the conventional display, the power consumption can be reduced. In addition, since the predetermined display brightness by the backlight can be obtained even when the aperture ratio is relatively low, the area of the light reflection layer can be increased, and a brighter reflective display than before can be realized.

  However, since the emitted light of the conventional backlight is generally diffused light and not parallel light, it is difficult to focus the light appropriately by the lens array.

  On the other hand, it is known that a plurality of prisms are formed on the bottom surface of a backlight, and parallel light is emitted by the prisms to increase luminance (for example, see Non-Patent Document 1).

As shown in FIG. 9 which is a bottom view, the backlight includes a light guide plate 24 on which a plurality of prisms 22 are formed and a light source such as an LED (light emitting diode) 21. The LEDs 21 are provided at the corners of the light guide plate 24. Each prism 22 is formed in a triangular groove shape, and the groove length direction is arranged so as to be orthogonal to the radial direction centering on the LED 21. In other words, the prisms 22 are arranged side by side in a concentric substantially arc shape centering on the LED 21. Each prism 22 reflects light incident on the inside of the light guide 24 from the LED 21 toward the liquid crystal cell from the upper surface of the light guide plate 24 and emits the light.
JP 2002-333619 A “IDW'02 Proceedings” p. 509-512

  Therefore, it is conceivable to apply a backlight on which a prism is formed in order to allow parallel light to enter the lens array. However, since the backlight having the prism has different directivity of the emitted light depending on the position of the light guide plate, it is difficult to properly collect the transmitted light simply by combining the lens array and the backlight. .

  Here, the directivity of the emitted light will be described. 10 and 11 show a measurement system for the emitted light of the backlight. FIG. 12 shows the measurement result of the emitted light characteristic.

  10 and 11, the Y direction that is the first direction is a radial direction around the LED 21, and the X direction that is the second direction is a direction orthogonal to the Y direction. In FIG. 11, the Z direction is the normal direction of the light guide plate (the direction orthogonal to the paper surface in FIG. 10), and is the direction orthogonal to both the X direction and the Y direction. The characteristics of the emitted light were measured at each measurement location A, B, C on an arc centered on the LED 21 as shown in FIG.

  FIG. 12 shows the relationship between the polar angle of the outgoing light component in the X direction and the Y direction and the luminance (the intensity of the outgoing light). Here, the polar angle in the X direction is an angle with respect to the axis in the Z direction in the outgoing light component on the XZ plane, and the polar angle in the Y direction is an angle with respect to the axis in the Z direction in the outgoing light component on the YZ plane. It is.

  As shown in FIG. 12, the luminance of the emitted light is maximum in the Z direction in both the X direction and the Y direction, but it can be seen that it has a predetermined directivity. That is, the half value width of the luminance of the emitted light in the X direction is about ± 3 °, and the directivity is very high, and the emitted light is substantially parallel light. On the other hand, the half value width of the luminance of the emitted light in the Y direction is about ± 15 ° and the directivity is low, and the emitted light is diffused light. This emission characteristic is schematically represented as an ellipse as shown in FIG.

  The present invention has been made in view of such various points, and an object of the present invention is to provide a liquid crystal display element having an opening through which light emitted from the backlight is transmitted and a condensing lens. By suitably condensing, the brightness of transmitted light that passes through the opening is increased as much as possible with respect to the opening having a predetermined size.

In order to achieve the above object, according to the present invention, the reflecting surface of the prism provided on the light guide plate of the backlight extends in the second direction orthogonal to the first direction which is the radial direction centering on the LED light source. while forming an opening for forming the light-shielding film of the liquid crystal cell converging lens is provided, the maximum opening width in a first direction, and to be larger than the maximum opening width in the second direction.

Specifically, the liquid crystal display element according to the present invention is a light guide that diffuses light incident from an incident surface, which is a side surface, and emits the diffused light to the outside from an exit surface extending perpendicularly to the incident surface. modulating an optical plate, a backlight having an LED light source disposed to face the incident surface of the light guide plate, provided opposite to the exit surface of the upper Kishirube light plate, the light emitted from the emitting surface a liquid crystal display device comprising a liquid crystal cell, the light guide plate is provided with a plurality of prisms having a reflecting surface for emitting light which enters the light guide plate to the outside of the anti shines light guide plate, the prism The reflective surface of the light guide plate is formed so as to extend in a second direction orthogonal to the first direction, which is the radial direction of the circle centered on the position of the LED light source , when viewed from the normal direction of the light exit surface of the light guide plate The liquid crystal cell is emitted from the light guide plate. A light shielding film for shielding at least a portion of the light was provided with a plurality of openings formed in the light shielding film, and a condensing lens provided between the opening portion and the light guide plate, the opening , when viewed from the normal direction of the emission surface of the light guide plate, the maximum opening width in the first direction, is formed by pores greater than the maximum opening width in the second direction.

  The said light shielding film may be comprised in the light reflection layer which reflects external light.

Preferably, the liquid crystal cell includes a plurality of pixel regions, and the opening and the condensing lens are each provided in each pixel region.

That is, according to the present invention, the light of the LED light source that enters the light guide plate from the incident surface is transmitted radially in the first direction inside the light guide plate. The light traveling inside the light guide plate is reflected by the reflecting surface of the prism and is emitted to the outside from the exit surface of the light guide plate.

  At this time, since the reflecting surface of the prism is formed so as to extend in the second direction orthogonal to the first direction, which is the light traveling direction, the component in the second direction of the light emitted to the outside of the light guide plate is While the directivity is high and becomes parallel light, the component in the first direction of the light emitted to the outside of the light guide plate has low directivity and becomes diffuse light. These lights emitted from the light guide plate are collected by a condenser lens and then transmitted through an opening formed in the light shielding film of the liquid crystal cell.

Here, in order to increase the luminance of the light transmitted through the opening, it is desirable that the light collected by the condenser lens is transmitted through the opening more. As shown in FIG. 4, parallel light with high directivity can be collected in a small area by a condensing lens, but diffused light with low directivity uses a condensing lens as shown in FIG. 5. However, it can collect light only in a relatively wide area. In the present invention, since the maximum opening width in the first direction at the opening is larger than the maximum opening width in the second direction when viewed from the normal direction of the exit surface of the light guide plate, among the light emitted from the light guide plate, The component in the first direction with low directivity efficiently transmits through the opening having a relatively large opening width in the first direction. In addition, the component in the second direction with high directivity efficiently transmits through the opening having a relatively small opening width in the second direction.

  On the other hand, by making the opening width in the second direction relatively small, the light shielding region of the light shielding film can be maintained in a predetermined area. That is, it is possible to efficiently increase the luminance of light transmitted through the opening with respect to the opening having a predetermined size. Thereafter, the light transmitted through the opening is modulated by the liquid crystal cell, and a desired display is performed.

  When the light shielding film is configured as a light reflection layer that reflects external light, reflection display is performed by light reflected by the light reflection layer, while transmission display is performed by light transmitted through the opening. . In addition, when the opening and the condensing lens are provided corresponding to each pixel region of the liquid crystal cell, the light condensed by each condensing lens is transmitted through the corresponding opening, respectively, Supplied to the area.

According to the present invention, since the maximum opening width in the first direction in the opening formed in the light shielding film is larger than the maximum opening width in the second direction when viewed from the normal direction of the exit surface of the light guide plate, the light is reflected by the prism. As a result, more light that is emitted from the light guide plate and has directivity can be transmitted through the opening. As a result, the brightness of the transmitted light with respect to the opening having a predetermined size can be suitably increased. Furthermore, since the light use efficiency of the backlight can be improved, power consumption can be reduced.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiment.

Embodiment 1 of the Invention
1 to 7, 9, and 10 show Embodiment 1 of the liquid crystal display element according to the present invention.

  As shown in FIG. 1 which is a cross-sectional view, the liquid crystal display element 10 is provided facing the backlight 2 on the back side (lower side in FIG. 1) and emitted from the backlight 2. And a liquid crystal cell 1 for modulating light. The liquid crystal display element 10 is configured as a transflective liquid crystal display element that reflects external light to perform reflective display, and transmits light from the backlight 2 to perform transmissive display.

  The backlight 2 includes a light source 21, a light guide plate 24 that guides light from the light source 21, a reflection plate 23 provided below the light guide plate 24, and a prism sheet 25 provided above the light guide plate 24. And.

  The light guide plate 24 is made of a transparent medium such as polycarbonate or polymethyl methacrylate, and is formed in a rectangular flat plate shape as viewed from above in FIG. 1 as shown in FIG. 1 and FIG. 9 which is a bottom view. Yes. The light source 21 includes one light emitting diode (hereinafter referred to as LED), and is provided at one corner of the light guide plate 24 as shown in FIG. The light guide plate 24 is configured to guide the light of the LEDs 21 incident from the corners over the entire interior of the light guide plate 24. In addition, as the light source 21, in addition to the LED, another light source having a sufficiently narrow width as compared with the width dimension of the light guide plate 24 may be applied.

  The reflecting plate 23 is made of, for example, an aluminum film, and is disposed below the light guide plate 24 as shown in FIG. The luminance of the display light is improved by reflecting the light emitted from the lower surface of the light guide plate 24 toward the upper liquid crystal cell 1 side. The prism sheet 25 is for refracting light emitted from the upper surface of the light guide plate 24 in the normal direction of the light guide plate 24.

  The light guide plate 24 includes a plurality of prisms 22 that reflect the light incident on the inside of the light guide plate 24 by the reflection surface 22 a and emit the light to the outside of the light guide plate 24. As shown in FIG. 1, the plurality of prisms 22 are formed on the bottom surface of the light guide plate 24, and are arranged in a matrix as shown in FIG. Each prism 22 is configured in a triangular groove shape having two reflecting surfaces 22a, for example, as shown in FIG. 6 which is an enlarged view.

  As shown in FIGS. 9 and 10, the reflecting surface 22 a of the prism 22 extends in the X direction (second direction) orthogonal to the Y direction (first direction) that is the radial direction centering on the LED 21. Is formed. In other words, the prism 22 is configured as a groove extending in the X direction. The inclination angle of the reflection surface 22 a is defined so that the light inside the light guide plate 24 is efficiently emitted in the normal direction of the light guide plate 24.

  In FIG. 9, for the sake of simplicity, the interval between the adjacent prisms 22 is described as being constant, but in practice, the configuration is such that the interval between the prisms 22 decreases as the distance from the LED 21 increases. Has been. As a result, the luminance characteristics of the light emitted from the backlight 2 are made uniform over the entire surface of the light guide plate 24.

  As shown in FIG. 1, the liquid crystal cell 1 includes a first substrate 11 in which switching elements such as TFTs are provided in a matrix, a liquid crystal layer 16 provided on the first substrate 11, and the liquid crystal layer. 16 and a second substrate 12 provided on 16. That is, the liquid crystal layer 16 is interposed between the first substrate 11 and the second substrate 12 which are a pair of substrates facing each other.

  Further, the liquid crystal cell 1 includes a light shielding film 13 that shields at least a part of light emitted from the light guide plate 24, a plurality of openings 15 formed in the light shielding film 13, and the openings 15 and the light guide plate. 24 and a condenser lens 14 provided between them. The liquid crystal cell 1 has a plurality of pixel regions 5 corresponding to the switching elements.

  The first substrate 11 is composed of an insulating transparent substrate. On the lower surface of the first substrate 11, a transparent electrode 17 and RGB color filter layers (not shown) are provided.

  Similar to the first substrate 11, the second substrate 12 is composed of an insulating transparent substrate. A driving circuit (not shown) for driving the light shielding film 13, the transparent electrode 18, and the liquid crystal layer 16 is provided on the upper surface of the second substrate 12.

  The light shielding film 13 is configured as a light reflecting layer 13 that reflects external light incident from the liquid crystal cell 1 side. Thus, the light reflecting layer 13 transmits the light of the backlight 2 through the opening 15, while reflecting outside light in the reflection region other than the opening 15.

  As shown in FIG. 2, the opening 15 is provided corresponding to each pixel region 5 and is formed in a rectangular opening extending in the Y direction. In other words, each opening 15 is formed in an opening having a different aspect ratio, and is arranged radially from the LED 21. FIG. 3 shows an enlarged view of the light reflecting layer 13 in one pixel region 5. The pixel region 5 is formed in, for example, a square whose side is a. The opening width b in the Y direction at the opening 15 is larger than the opening width c in the X direction.

  The opening 15 was manufactured by precisely patterning the predetermined opening shape by photolithography on the light reflecting layer 13 formed by laminating a metal thin film on the second substrate 12.

  As shown in FIG. 1, the condenser lens 14 is provided corresponding to each pixel region 5 on the lower surface of the second substrate 12. That is, the condenser lens 14 is provided corresponding to each opening 15. Each condensing lens 14 is formed of a spherical lens, and constitutes a lens array 14 as a whole. Thus, the condenser lens 14 condenses the light emitted from the backlight 2 in the opening 15.

  As a manufacturing method of the lens array 14, it is preferable to use a photopolymer replica. In this method, first, an ultraviolet curable resin is sealed between the mold master precisely formed in the shape of the lens array 14 and the second substrate 12. Subsequently, the encapsulated resin is cured by irradiating with ultraviolet rays. After completely curing, the mold is gently peeled off. By this method, it is possible to manufacture a lens array 14 that is easy, has high productivity, and has high optical characteristics. The ultraviolet curable resin used as the material of the lens array 14 is preferably a resin material that is completely cured and has high transparency and low birefringence.

  The light condensing characteristic of the lens array 14 is determined by the focal length determined by the refractive index and the radius of curvature of the resin constituting the lens array 14 and the thickness of the second substrate 12. FIG. 7 shows the relationship between the thickness of the second substrate 12 and the amount of light transmitted through the opening 15 when the pixel shape is a square having a side length a of 80 μm. It is the result calculated by. The calculation conditions are that the resin constituting the lens array 14 and the refractive index of the second substrate 12 are 1.52, the radius of curvature of the lens array 14 is 81.6 μm, the opening width b of the opening 15 is 54 μm, and the opening The width c is 12 μm.

  As shown in FIG. 7, as an optimum value, when the thickness of the second substrate 12 is about 130 μm, about 3.3 times the brightness can be obtained as compared with the case where the lens array 14 is not provided. I understood.

  Although not shown, a polarizing plate and a retardation plate are provided on the upper surface of the first substrate 11 and the backlight 2 side of the second substrate 12, respectively. In particular, the polarizing plate and the retardation plate provided on the backlight 2 side of the second substrate 12 are desirably provided at the interface between the second substrate 12 and the lens array 14. As a result, it is possible to prevent a decrease in contrast caused by a change in the polarization axis due to the light condensing effect of the lens array 14 and improve display quality.

  Next, the operation of the liquid crystal display element 10 according to the present invention will be described.

  When performing reflective display, the light source 21 of the backlight 2 is turned off. Ambient external light is incident on the liquid crystal layer 16 through the first substrate 11 from above the liquid crystal cell 1. External light incident on the liquid crystal layer 16 is reflected by the reflection region of the light reflection layer 13 and modulated by the liquid crystal layer 16. Thus, predetermined light is emitted to the outside of the first substrate 11 and desired display is performed.

  When performing transmissive display, the light source 21 of the backlight 2 is turned on. The light from the light source 21 enters the light guide plate 24 and travels radially in the Y direction inside the light guide plate 24. The light traveling inside the light guide plate 24 is reflected by the reflecting surface 22 a of the prism 22 and is emitted to the outside of the light guide plate 24.

  At this time, since the reflecting surface 22a of the prism 22 is formed so as to extend in the X direction orthogonal to the Y direction, which is the light traveling direction, the X direction component of the light emitted from the light guide plate has high directivity. On the other hand, the X-direction component of the light emitted from the light guide plate has low directivity and becomes diffused light. These lights emitted from the light guide plate 24 are collected by the condenser lens 14 and then pass through the opening 15 formed in the light reflection layer 13.

  Here, for example, the parallel light incident on the condenser lens 14 at an incident angle of ± 3 ° is concentrated in a relatively small region d by the condenser lens 14 as shown in FIG. On the other hand, for example, diffused light incident on the target lens 14 at an incident angle of ± 15 ° is collected in a relatively wide area e by the condenser lens 14 as shown in FIG. Therefore, in order to increase the luminance of the light transmitted through the opening 15, it is desirable to transmit more parallel light incident on the condenser lens 14 through the opening 15.

  In the present embodiment, as shown in FIG. 3, since the opening width b in the Y direction in the opening 15 is larger than the opening width c in the X direction, the Y direction component of the light emitted from the light guide plate 24 is condensed. After being condensed by the lens 14, the light efficiently passes through the opening 15 having a large opening width in the Y direction. Further, the X-direction component of the light emitted from the light guide plate 24 is condensed by the condenser lens 14 and then efficiently passes through the opening 15 having a small opening width in the X direction. In other words, the amount of transmitted light increases with respect to the opening 15 having a predetermined opening area. Thereafter, the light whose luminance has been increased is transmitted through the opening 15 and modulated by the liquid crystal cell 1 to perform a desired display.

-Effect of Embodiment 1-
Therefore, according to the first embodiment, since the opening width b in the Y direction of the opening 15 is larger than the opening width c in the X direction, X of the light reflected by the prism 22 and emitted from the light guide plate 24 is X. More parallel light that is emitted in the direction and collected by the condenser lens 14 can be transmitted through the opening 15 more. As a result, the brightness of the transmitted light can be suitably increased while the opening area of the opening 15 is relatively small, so that the utilization efficiency of both external light and backlight light can be improved. That is, the luminance of display light in both transmissive display and reflective display can be increased while reducing the power consumption of the backlight.

  In other words, it is possible to reduce the power consumption of the backlight for obtaining predetermined display light luminance. That is, the transflective liquid crystal display element 10 according to the present embodiment is about three times as bright as the transmissive display by the backlight, compared to the transflective liquid crystal display element having a predetermined aperture ratio and not using the conventional lens array. Can be realized.

  In addition, as a manufacturing method of the condensing lens 14, the heat dripping method which heats the patterned photosensitive resin and shape | molds in a lens shape, the method of modulating a refractive index by ion diffusion, the method of producing by etching, etc. are used. You can also Further, instead of the lens array 14, a hologram that exhibits an action similar to a lens may be used. Since the hologram can be manufactured by an easy method such as interference exposure, the liquid crystal display element having the characteristics of the present invention can be manufactured at a relatively low cost.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the first embodiment.

  That is, in Embodiment 1 described above, the LEDs 21 are provided at the corners of the light guide plate 24, but may be provided at the center of one side of the light guide plate 24 as shown in FIG. Also in this case, each opening 15 is formed in a rectangular opening extending in the Y direction (that is, the radial direction centering on the LED 21), and is arranged radially from the LED 21. Although not shown, each prism of the light guide plate 24 is formed so as to extend in the X direction orthogonal to the Y direction with respect to the LED 21. Even if it does in this way, the effect similar to the said Embodiment 1 can be acquired.

  In Embodiment 1 described above, the opening shape of the opening 15 is rectangular. However, the present invention is not limited to this, and the aspect ratios of, for example, an ellipse and an ellipse are different in consideration of the light emission characteristics of the backlight. You may comprise in another shape.

  In the first embodiment, the lens array 14 is provided on the lower surface of the second substrate 12 (that is, the backlight 2 side). However, by using a method of modulating the refractive index by ion diffusion, A lens array may be formed inside. This simplifies the handling of the lens array and allows easy manufacture.

  Furthermore, although the condensing lens is a spherical lens, this is not necessarily the case, and an aspherical lens, a Fresnel lens, a diffractive lens, or the like may be used as long as it is a lens that can condense in the opening.

  In the first embodiment, the pixel region 5 has a square shape, but may have any other shape such as a rectangle. Further, although one condenser lens is provided for one pixel region 5, a plurality of openings 15 are provided for one pixel region 5, and the same number of openings 15 is provided. A condensing lens 14 may be provided.

  Further, the prism 22 is not limited to the triangular groove, and may be configured by, for example, a groove having a circular arc cross section whose reflecting surface is a curved surface.

  In the first embodiment, the transflective liquid crystal display element has been described. However, as another embodiment, a transmissive liquid crystal display element may be used. That is, instead of the light reflecting layer 13, a light shielding film that blocks light may be provided at the boundary of each pixel region, and a plurality of openings may be formed in the light shielding film. Also by this, the same effect as the first embodiment can be obtained. In addition, the light shielding region of the light shielding film can be maintained at a predetermined area, and the luminance of light transmitted through the opening can be efficiently increased. In particular, a bright and good display can be performed in a high-resolution liquid crystal display element with a low aperture ratio.

As described above, the present invention is useful for a liquid crystal display element used in a display device such as an information display of an electronic information device, particularly when increasing the luminance of transmitted light with respect to an opening having a predetermined size. Is suitable.
The

3 is a cross-sectional view showing the liquid crystal display element of Embodiment 1. FIG. It is a top view which shows a light reflection layer and an opening part. FIG. 3 is an enlarged plan view showing one pixel region in FIG. 2. It is explanatory drawing which shows the condensing state of the parallel light which injects into a condensing lens. It is explanatory drawing which shows the condensing state of the diffused light which injects into a condensing lens. It is explanatory drawing which shows the optical path of the light guide | induced to a light guide and radiate | emitted. It is a graph which shows the relationship between the thickness of a board | substrate, and the light beam quantity of the light which permeate | transmits an opening part. It is a top view which shows the opening part of other embodiment. It is a bottom view which shows the backlight provided with the prism. It is a top view which shows the measurement system of the emitted light of a backlight. It is a perspective view which shows the measurement system of the emitted light of a backlight. It is a graph which shows the characteristic of the emitted light of the backlight in a X direction and a Y direction.

Explanation of symbols

X (second direction)
Y (first direction)
DESCRIPTION OF SYMBOLS 1 Liquid crystal cell 2 Backlight 5 Pixel area 10 Liquid crystal display element 13 Light reflection layer (light shielding film)
14 Lens array (Condenser lens)
15 Opening 21 LED (light source)
22 Prism 22a Reflecting surface 24 Light guide plate

Claims (3)

A light guide plate that diffuses light incident from an incident surface, which is a side surface, and emits the diffused light to the outside from an output surface that extends perpendicularly to the incident surface; and opposed to the incident surface of the light guide plate A backlight having an LED light source disposed ;
Provided opposite the exit surface of the upper Kishirube light plate, a liquid crystal display device comprising a liquid crystal cell for modulating the light emitted from the exit surface,
The light guide plate includes a plurality of prisms having a reflecting surface for emitting light which enters the light guide plate to the outside of the anti shines light guide plate,
The reflecting surface of the prism extends in a second direction orthogonal to a first direction that is a radial direction of a circle centered on the position of the LED light source when viewed from the normal direction of the exit surface of the light guide plate. Formed into
The liquid crystal cell is provided between a light-shielding film that shields at least part of light emitted from the light guide plate, a plurality of openings formed in the light-shielding film, and the openings and the light guide plate. With a condenser lens,
The opening is viewed from the normal direction of the emission surface of the light guide plate, the maximum opening width in the first direction, is formed by pores greater than the maximum opening width in the second direction <br A liquid crystal display element characterized by the above. In claim 1,
The liquid crystal display element, wherein the light shielding film is formed in a light reflecting layer that reflects external light. In claim 1,
The liquid crystal cell includes a plurality of pixel regions,
A liquid crystal display element, wherein one opening and one condenser lens are provided in each pixel region.

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