JP5263230B2 - Liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display which controls the field of view of display between a wide view and a narrow view. <P>SOLUTION: A surface light source 9 includes a deflection means 10 for emitting light deflected by a plurality of arc-shaped deflection surfaces 14 formed in a concentric circle shape, a first light emitting element 25a at a center part of an incident part 12 thereof, and two second light emitting elements 25b at positions shifted from the center of the incident part 12. The surface light source 9 is configured to radiate first illumination light having an intensity distribution wherein intensity of front light is higher than the intensity of inclined light when the first light emitting element 25a is turned on, and second illumination light having an intensity distribution wherein intensity of inclined light is higher than the intensity of the front light when the second light emitting elements 25b is turned on. A display image data signal is applied to each pixel of a liquid crystal display element 1. The first light emitting element 25a is turned on in synchronization with application of the display image data signal when the narrow view is selected. The first and second light emitting elements 25a and 25b are simultaneously or alternately turned on in synchronization with application of the display image data signal when the wide view is selected. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a visual field control type liquid crystal display device.

The liquid crystal display device is irradiated on the opposite side a plurality of pixels for controlling the transmittance of light and the observation side of the liquid crystal display device having a screen area that is arranged in a matrix, the illumination light toward the liquid crystal display element surface A light source is arranged (see Patent Document 1).

  By the way, in a liquid crystal display device mounted on an electronic device such as a mobile phone, the display field of view is a wide field of view and a narrow field of view so that the display cannot be seen by anyone other than the user of the liquid crystal display device. There is a demand for visual field controllability that can be switched.

  Conventionally, as a visual field control type liquid crystal display device, a liquid crystal display device in which a visual field limiting liquid crystal element for limiting the visual field is arranged on one surface side of a liquid crystal display element for displaying an image has been proposed. The visual field limiting liquid crystal element includes a liquid crystal sealed between a pair of substrates, and the liquid crystal molecules are divided into a plurality of areas corresponding to the screen of the liquid crystal display element. The inner surfaces of the pair of substrates facing each other are aligned in an alignment state having a field of view in a direction inclined in one direction with respect to the line direction and in an alignment state having a field of view in a direction inclined in a direction opposite to the direction. Each is provided with an electrode having a predetermined shape corresponding to each of the divided regions (see Patent Document 2).

  The liquid crystal display device is configured to limit visibility of the display of the liquid crystal display element by reducing visibility from an oblique direction by applying a voltage between electrodes of the visual field limiting liquid crystal element. When a voltage is not applied between the electrodes of the liquid crystal element for display, that is, when the visual field limiting liquid crystal element is in a non-display state, the display image of the liquid crystal display element can be seen in a wide visual field.

  On the other hand, when a voltage is applied between the electrodes of the visual field limiting liquid crystal element, when viewed from one direction with respect to the front direction and a direction inclined in the opposite direction, the display image of the liquid crystal display element is Display of each segmented region having a field of view in a direction inclined in one direction of the liquid crystal element for limiting the field of view and display corresponding to the electrode of the predetermined shape in each segmented region having a field of view in a direction inclined in the opposite direction Since it is hidden, the display image of the liquid crystal display element cannot be recognized from the one direction and the direction inclined in the opposite direction, the field of view of the display image is apparently limited, and the field of view of the display is narrowed. .

JP 2003-149599 A JP 2004-133334 A

  However, the field-of-view-limiting liquid crystal element must be subjected to complicated alignment processing (rubbing processing of the alignment film) in which the direction is different for each of the divided regions on the inner surfaces of the pair of substrates. difficult.

  Therefore, the conventional visual field control type liquid crystal display device provided with the visual field limiting liquid crystal element has a problem of high cost.

  An object of the present invention is to provide a liquid crystal display device that can control the display field of view to a narrow field of view and a wide field of view and can be obtained at low cost.

In order to achieve the above-described object, an aspect of the liquid crystal display device according to the present invention includes a liquid crystal display element in which a plurality of pixels are arranged in a matrix, and a liquid crystal display element disposed so as to face the liquid crystal display element. A light guide plate having different angles indicating the peak value of the emitted light emitted from the surface facing the liquid crystal display element according to the incident position of the incident light, and the light emitted from the surface of the light guide plate facing the liquid crystal display element A first light emitting element that emits light toward the light guide plate, and is disposed at a position where an angle indicating a peak value of the emitted light is an angle perpendicular to an emission surface of the emitted light, and the light guide plate Is arranged at a position where the angle indicating the peak value of the emitted light emitted from the surface facing the liquid crystal display element is inclined with respect to the emission surface of the emitted light, and emits light toward the light guide plate A second light emitting element A first memory in which image data sequentially supplied from the storage unit is stored, a second memory in which fixed image data registered in advance is stored, and an image to be displayed on the liquid crystal display element. A display control unit that alternately switches and outputs the image based on the image data stored in the second memory and the image based on the image data stored in the second memory, and the display control unit A light source control unit that switches a light emitting element to emit light between the first light emitting element and the second light emitting element in synchronization with an image switching timing by the display unit, wherein the display control unit is the liquid crystal display element When outputting an image based on the image data stored in the first memory, the light source control unit causes the first light emitting element to emit light and causes the second light emitting element to emit light. When the display control unit causes the liquid crystal display element to output an image based on the image data stored in the second memory, the light source control unit causes the second light emitting element to emit light and the first light emitting element to emit light. The light emitting element is not caused to emit light .

According to the present invention, it is possible to provide a liquid crystal display device which can control the display field of view to a narrow field of view and a wide field of view and which can be obtained at low cost.

1 is an exploded perspective view of a liquid crystal display device showing a first embodiment of the present invention. The front view seen from the output side of the surface light source of the said liquid crystal display device. Sectional drawing which abbreviate | omitted hatching along the III-III line of FIG. FIGS. 3A and 3B are diagrams of emitted light when the first light emitting element of the surface light source is turned on and when the second light emitting element is turned on. FIGS. FIG. 4 is an intensity distribution diagram of irradiation light when the first light emitting element of the surface light source is turned on, when the second light emitting element is turned on, and when the first and second light emitting elements are turned on simultaneously. FIG. 3 is an outgoing ray diagram for narrow-field display of the liquid crystal display device. FIG. 3 is an outgoing ray diagram when the liquid crystal display device performs wide-field display. FIG. 4 is a drive sequence diagram of a liquid crystal display element and a surface light source during narrow field display and wide field display in a field sequential liquid crystal display device. The block circuit diagram of the drive means which shows the 2nd Example of this invention. FIG. 10 is a drive sequence diagram of a liquid crystal display element and a surface light source during narrow field display and wide field display in the field sequential liquid crystal display device of the second embodiment. Driving sequence of liquid crystal display element and surface light source in narrow-field display and wide-field display in a liquid crystal display device in which the liquid crystal display element of the second embodiment is provided with three color filters of red, green and blue Figure. The figure which shows an example of the display seen from the front direction at the time of the narrow-field display of the liquid crystal display device of a 2nd Example, and the display seen from the direction inclined in the left direction and the right direction. The figure which shows an example of the display seen from the front direction at the time of the wide-field display of the liquid crystal display device of a 2nd Example, and the display seen from the direction inclined in the left direction and the right direction. The front view seen from the output side of the surface light source which shows the 3rd Example of this invention. Sectional drawing which abbreviate | omitted hatching along the XV-XV line | wire of FIG.

(First embodiment)
1 to 8 show a first embodiment of the present invention, and FIG. 1 is an exploded perspective view of a liquid crystal display device.

The liquid crystal display device, a plurality of pixels for controlling the transmittance of light (not shown) having a screen area 1a arranged in a matrix form, the image data signal is applied to each of the plurality of pixels, the image data The liquid crystal display element 1 for displaying an image corresponding to the above and the observation side (left side in FIG. 1) of the liquid crystal display element 1 are arranged on the opposite side of the liquid crystal display element 1. First illumination light having an intensity distribution higher than the intensity of oblique light emitted in the direction inclined in one direction and the opposite direction with respect to the normal direction, and the intensity of the front light emitted in the normal direction; A surface light source 9 for irradiating the second illumination light having an intensity distribution of oblique light higher than that of the front light ; and a driving means 27 for driving the liquid crystal display element 1 and the surface light source 9. Yes.

Although the internal structure of the liquid crystal display element 1 is not shown, a pair of transparent substrates 2 and 3 joined via a frame-shaped sealing material 4 surrounding the screen region 1a and the substrates 2 and 3 are opposed to each other. Liquid crystal sealed in a region surrounded by the sealing material 4 between the pair of substrates 2 and 3 and a transparent electrode which is provided on each inner surface and forms a plurality of pixels arranged in a matrix by regions facing each other. And a pair of polarizing plates 5 and 6 disposed on the outer surfaces of the pair of substrates 2 and 3, respectively, and one of the pair of substrates 2 and 3, for example, the substrate 3 on the observation side and the polarizing plate 6 on that side. It consists retardation plate 7, for increasing the placed display contrast between.

In the liquid crystal display element 1, a plurality of pixel electrodes are arranged in a matrix in the row direction and the column direction on the inner surface of one substrate, for example, the substrate 2 opposite to the observation side, and the other substrate, that is, the observation side. An active matrix liquid crystal display element in which a single-film counter electrode facing the array region of the plurality of pixel electrodes is provided on the inner surface of the side substrate 3, and the plurality of pixels are disposed on the inner surface of the opposite substrate 2. an active element made of respective electrodes connected to TFT, and each row of the TFT of the plurality supplying the gate signal scanning lines, a plurality of data lines for supplying data signals to each column of TFT, is provided.

  The opposite side substrate 2 has a driver mounting portion 2a extending outward from the observation side substrate 3, and the plurality of gate lines and data lines are connected to the LSI mounted on the driver mounting portion 2a. Connected to the display driver 8.

  Further, an alignment film is provided on the inner surfaces of the pair of substrates 2 and 3 so as to cover the electrodes, and the liquid crystal molecules of the liquid crystal layer are defined by the alignment film between the pair of substrates 2 and 3. It is oriented in the orientation state.

The liquid crystal display device 1, the liquid crystal molecules a TN or STN type were twisted, the liquid crystal molecules with respect to the substrate 2 side vertically into oriented so the vertical alignment type, the substrate 2 without twisting the liquid crystal molecules, and to three sides flat horizontal alignment type has been oriented to the row, a liquid crystal or a liquid crystal display device of the molecule a bend alignment type to bend or ferroelectric or anti-ferroelectric liquid crystal display device, the pair The polarizing plates 5 and 6 are arranged with their transmission axes oriented so as to obtain good contrast characteristics.

  In the liquid crystal display element 1, a vertical electric field (electric field in the thickness direction of the liquid crystal layer) is generated between the electrodes provided on the inner surfaces of the pair of substrates 2 and 3 to change the alignment state of the liquid crystal molecules. For example, a comb-like first and second electrode for forming a plurality of pixels is provided on the inner surface of one of the pair of substrates 2 and 3, and a horizontal electric field ( A lateral electric field control type that changes the alignment state of the liquid crystal molecules by generating an electric field in a direction along the substrate surface may be used.

  Further, the liquid crystal display element 1 may be a normally white mode display element or a normally black mode display element.

The surface light source 9 disposed on the side opposite to the viewing side of the liquid crystal display element 1 is formed with an incident part 12 for making light incident on one edge side of the liquid crystal display element 1, and the liquid crystal display and along a device 1 and a flat line plane, inclined at the same angle in the radial direction along a semicircle around the center portion in the length direction of the incident portion 12, is incident from the incident part 12 light The direction change means 10 in which a plurality of arc-shaped direction change surfaces 14 that are emitted toward the liquid crystal display element 1 are changed in a concentric manner, and the central portion of the incident portion 12 of the direction change means 10 are opposed to each other. A first light emitting element 25a that emits light that spreads radially from the center of curvature of the arc-shaped diverting surface 14 toward the incident portion 12 of the diverting means 10, and an incident portion of the diverting means 10 The position shifted to one end side in the length direction of the incident portion 12 with respect to the central portion of the 12 and the other end A plurality of light beams that are arranged so as to face each other and that spread radially from the point shifted from the center of curvature O of the arc-shaped turning surface 14 toward the incident portion 12 of the turning means 10. the second consists emitting element 25b, the.

  The surface light source 9 of this embodiment includes two second light emitting elements 25b, and these second light emitting elements 25b are arranged on the incident portion 12 of the turning means 10 with the arrangement position of the first light emitting elements 25a interposed therebetween. The light incident portion 12 is disposed so as to be opposed to two positions shifted from each other by an equal distance on one end side and the other end side in the length direction of the incident portion 12 with respect to the center portion.

  In the surface light source 9, the intensity of the front light emitted in the normal direction of the liquid crystal display element 1 is tilted in one direction and the opposite direction with respect to the normal direction by the lighting of the first light emitting element 25a. The first illumination light having an intensity distribution higher than the intensity of the oblique light emitted in the direction is irradiated toward the liquid crystal display element, and the lighting of the two second light emitting elements 25b causes the intensity of the oblique light to be the front. The second illumination light having an intensity distribution higher than the light intensity is irradiated toward the liquid crystal display element 1.

  2 is a front view of the surface light source 9 viewed from the emission side, FIG. 3 is a cross-sectional view in which hatching along the line III-III in FIG. 2 is omitted, and the turning means 10 is, for example, an acrylic resin plate or the like An incident end face (incident part) 12 for allowing light to enter an end face on one edge side of the liquid crystal display element 1 is formed in the peripheral surface of the plate-like transparent member, and the liquid crystal display element 1 of the transparent member A light exit surface 13 for light incident from the incident end surface 12 is formed on the plate surface opposite to the plate surface, and a plate surface on the opposite side is formed along a semicircle centered on the central portion in the length direction of the incident end surface 12. A plurality of arc-shaped diverting surfaces 14 that are inclined at the same angle in the radial direction and change the direction of the light incident from the incident end surface 12 to be emitted from the exit surface 13 toward the liquid crystal display element 1 side are concentrically formed. The light guide plate 11 is formed.

  The plurality of arc-shaped diverting surfaces 14 of the light guide plate 11 are inclined surfaces inclined at a predetermined angle in a direction opposite to the exit surface 13 toward the center of the semicircle, and the liquid crystal display element It is formed concentrically at a pitch that is about the same as or smaller than the pixel pitch of one pixel.

The light guide plate 11, light incident from the incident end face 12, as indicated by arrows in FIG. 3, and internal reflection (total internal reflection at the interface between the outside air) by the plurality of arc-shaped diverting surface 14 The direction is changed, and the light is emitted from the exit surface 13 toward the liquid crystal display element 1, and the inclination angle of the plurality of arc-shaped diverting surfaces 14 is from the center of curvature of the arc-shaped diverting surface 14. light radiating in a direction along a plate surface and a flat line plane of the light guide plate 11 when made incident, from the exit surface 13 of the light guide plate 11, the direction along the normal of the liquid crystal display device 1 Is set to emit light having an intensity distribution in which a peak of the emitted light intensity exists.

  In this embodiment, of the light incident on the light guide plate 11 from the incident end face 12 on the rear side of the light guide plate 11 (outside of the surface on which the arc-shaped turning surface 14 is formed), the arc shape. A reflecting plate 15 that reflects light leaking to the rear side of the light guide plate 11 through the interface between the direction change surface 14 and the outside air is disposed.

The first and second light emitting elements 25a and 25b are solid light emitting elements in which an LED (light emitting diode) is molded with a transparent resin, the structure of which is not shown, and the light emitting point of the LED is on the emission side. of the emitted light, and a lens unit for radiating spread in a direction along the plate surface and a flat line plane of the light guide plate 11 from.

The first light emitting element 25a is disposed with the light emitting point of the LED opposed to the center of curvature O (see FIG. 4) of the arcuate direction change surface 14, and the two second light emitting elements 25b are respectively point P ₁ the incident end face 12 of the light guide plate 11 two shifted by an equal distance on the one end and the other end of the length direction with respect to the center of curvature of the light emitting point of the LED of the arcuate diverting surface 14 , P ₂ (see FIG. 4).

  FIGS. 4A and 4B are diagrams of light rays emitted from the light guide plate 11 when the first light emitting element 25a of the surface light source 9 is turned on and when the second light emitting element 25b is turned on. FIG. The outgoing light beam when the element 25a is turned on is shown, and (b) shows the outgoing light beam when the second light emitting element 25b is turned on.

As shown in FIG. 4A, when the first light emitting element 25a is turned on, the surface light source 9 emits from the first light emitting element 25a and enters the light guide plate 11 from its incident end face 12. light, that is, the direction of the light radiating along the center of curvature O to the plate surface and a flat line plane of the light guide plate 11 of the arcuate diverting surface 14, internal reflection by the plurality of arc-shaped diverting surface 14 Then, the light is emitted from the light exit surface 13 of the light guide plate 11 in the normal direction h of the liquid crystal display element 1.

4B, when the two second light emitting elements 25b are turned on, the surface light source 9 emits light from the second light emitting elements 25b and enters the light guide plate 11. incident from the end face 12 of light, i.e. in a direction extending radially along the plate surface and a flat line plane of the center of curvature offset point relative to O P _1, P ₂ from the light guide plate 11 of the arcuate diverting surface 14 The light is internally reflected by the plurality of arc-shaped diverting surfaces 14 to change its direction, and from the exit surface 13 of the light guide plate 11, one direction with respect to the normal direction h of the liquid crystal display element 1 and vice versa. The light is emitted in a direction inclined at an angle θ corresponding to the radius of curvature of the arcuate direction change surface 14.

That is, the two second light emitting elements 25b are configured such that the light emitting points of the respective LEDs have one end side and the other end in the length direction of the incident end face 12 of the light guide plate 11 with respect to the center of curvature of the arc-shaped turning surface 14. Of the second light emitting elements 25b on the right side when viewed from the observation side of the liquid crystal display element 1 because the two points P ₁ and P ₂ are arranged so as to face each other at equal distances from each other. The light emitted from the second light emitting element 25b is reflected from the observation side with respect to the reflection direction of the light from the center of curvature O (light emitted from the first light emitting element 25a) by the plurality of arc-shaped diverting surfaces 14. The light emitted from the second light-emitting element 25b on the left side as viewed from the observation side is reflected from the inner side in the direction inclined to the left as viewed from the observation side, and the light from the center of curvature O is reflected by the plurality of arc-shaped diverting surfaces 14. In the right direction when viewed from the observation side It is internally reflected in the stomach direction.

  As described above, the surface light source 9 has the intensity of the front light emitted in the normal direction h of the liquid crystal display element 1 in one direction with respect to the normal direction h by turning on the first light emitting element 25a. By irradiating the liquid crystal display element 1 with the first illumination light A having an intensity distribution higher than the intensity of the oblique light emitted in the direction inclined in the opposite direction, and by turning on the two second light emitting elements 25b, The second illumination light B having an intensity distribution in which the intensity of the oblique light is higher than the intensity of the front light is emitted toward the liquid crystal display element 1.

  In this embodiment, the surface light source 9 is arranged with the incident end surface 12 of the light guide plate 11 facing one of the edge portions (upper edge side in the figure) in the vertical direction of the screen of the liquid crystal display element 1. Therefore, when the two second light emitting elements 25b are turned on, the second illumination light B emitted from the surface light source 9 toward the liquid crystal display element 1 is the liquid crystal display element 1. The intensity of the oblique light emitted in the direction inclined to the left direction and the right direction of the screen with respect to the normal direction h is light having an intensity distribution higher than the intensity of the front light emitted in the normal direction h. .

  Further, as shown in FIG. 1, the surface light source 9 is disposed on the exit side of the light guide plate 11, and out of the light emitted from the exit surface 13 of the light guide plate 11, the normal line of the liquid crystal display element 1. An anisotropic diffusion plate 26 that diffuses light in a direction inclined with respect to the direction h is further provided.

  The anisotropic diffusion plate 26 is, for example, Lumisty (trade name) manufactured by Sumitomo Chemical Co., Ltd. In this embodiment, the direction is inclined in one direction and the opposite direction with respect to the normal direction of the diffusion plate. The light having a characteristic of diffusing light in a direction inclined at an angle in a range of 30 ° to 80 ° with respect to the normal direction is used.

  The anisotropic diffusion plate 26 diffuses light in directions inclined in the left and right directions of the screen of the liquid crystal display element 1 with the normal direction coincident with the normal direction h of the liquid crystal display element 1. It is arranged to let you.

  FIG. 5 is an intensity distribution diagram of the irradiation light of the surface light source 9 provided with the anisotropic diffusion plate 26, (a) is an intensity distribution of the irradiation light when the first light emitting element 25a is turned on, (b) ) Shows the intensity distribution of the irradiation light when the second light emitting element 25b is turned on, and (c) shows the intensity distribution of the irradiation light when the first and second light emitting elements 25a and 25b are turned on simultaneously. . In FIG. 5, the negative angle is the left angle when viewed from the viewing side with respect to the normal direction h (0 ° direction) of the liquid crystal display element 1, and the positive angle is the normal direction. On the other hand, it is an angle in the right direction when viewed from the observation side.

  As shown in FIGS. 5A and 5B, the surface light source 9 has a peak of emitted light intensity in a direction along the normal direction h of the liquid crystal display element 1 when the first light emitting element 25a is turned on. In particular, the intensity of the front light in a narrow angle range of about −10 ° to 10 ° is high, and the intensity of the outgoing light of the oblique light outside the angle range is about 10% or less of the intensity of the front light. When the second light emitting element 25b is turned on, the emitted light intensity has peaks in directions inclined by about −20 ° and about 20 ° with respect to the normal direction h. The intensity distribution of the emitted light in a direction further inclined than the peak direction is an intensity distribution close to a flat of about 2/3 to 1/3 of the emitted light intensity in the peak direction over a wide angle range up to about −80 ° and about 80 °. The second illumination light B is irradiated.

  Further, as shown in FIG. 5 (c), the surface light source 9 generates the first illumination light A and the second illumination light B by simultaneous lighting of the first and second light emitting elements 25a and 25b. The output light intensity in a direction that is overlapped and has a peak of the output light intensity in the direction along the normal direction h of the liquid crystal display element 1 and is inclined with respect to the normal direction h is about −80 ° to about −80 °. The combined illumination light A + B having an intensity distribution of about 2/3 to 1/5 of the emitted light intensity in the peak direction is irradiated over a wide angle range up to 80 °.

  On the other hand, the driving means 27 for driving the liquid crystal display element 1 and the surface light source 9 is not shown in its configuration, but a display image data signal corresponding to an image signal supplied from the outside to each pixel of the liquid crystal display element 1. When a visual field selection signal for selecting a narrow visual field display is input according to a visual field selection signal supplied from the outside, the first light source of the surface light source 9 is synchronized with the application of the display image data signal. When the light-emitting element 25a is turned on and a visual field selection signal for selecting a wide-field display is input, the first light-emitting element 25a of the surface light source 9 and two second light-emitting elements are synchronized with the application of the display image data signal. It comprises a drive circuit that lights the element 25b simultaneously.

  The narrow vision selection signal is supplied from the circuit unit of the electronic device to the drive control unit 34 by an operation of a visual field selection key provided in the electronic device such as a mobile phone equipped with a liquid crystal display device.

  In FIG. 8, the liquid crystal display element 1 is a display element that does not include a color filter, and the first and second light emitting elements 25a and 25b of the surface light source 9 are configured by LEDs of three colors of red, green, and blue, respectively. FIG. 6 is a drive sequence diagram of the liquid crystal display element 1 and the surface light source 9 in the field sequential liquid crystal display device, where (a) shows a drive sequence for narrow-field display and (b) shows a drive sequence for wide-field display. Show.

For this field sequential liquid crystal display device, one frame is divided into 3 fields t ₁ ~t ₃ a, when the narrow field of view display of FIG. 8 (a), in the first to third field t ₁ , T ₂ , t ₃ , a red unit color display image data signal, a green unit color display image data signal, and a blue unit color display image data signal for each pixel of the liquid crystal display element 1. Are sequentially applied, and the red, green, and blue LEDs of the first light emitting element 25a are selectively turned on from the surface light source 9 in synchronization with the application of the display image data signals of these unit colors. First illumination light, green first illumination light, and blue first illumination light are sequentially irradiated.

Further, at the time of wide-field display, as shown in FIG. 8B, a red unit is provided for each pixel of the liquid crystal display element 1 for each of the first to _third fields t ₁ , t ₂ , and t _3. A color display image data signal, a green unit color display image data signal, and a blue unit color display image data signal are sequentially applied and synchronized with the application of each unit color display image data signal. The first and second illumination lights of red and the first and second illumination lights of green are emitted from the surface light source 9 by simultaneously lighting the same color LEDs of the first and second light emitting elements 25a and 25b. And blue first and second illumination lights are sequentially irradiated.

In the liquid crystal display device, the liquid crystal display element 1 includes three color filters of red, green, and blue that face the plurality of pixels, respectively, and the surface light source 9 generates white first illumination light. A liquid crystal display device adapted to irradiate with the second illumination light may be used. In that case, red, green, and blue color filters of the liquid crystal display element 1 are respectively applied to the respective pixels corresponding to the red, green, and blue color filters. green, is applied to each color display image data signals of blue, when the narrow field of view display, by irradiating the first illumination light white color from the display image data signal wherein the surface light source 9 in synchronism with the application of a wide viewing when the display, the display image data signals in synchronism with the application of, and irradiates the first and second illumination light white color from the surface light source 9.

  Thus, in the liquid crystal display device of this embodiment, the driving means 27 applies the display image data signal corresponding to the image signal to each pixel of the liquid crystal display element 1, and synchronizes with the application of the display image data signal. By turning on the first light emitting element 25a of the surface light source 9, the intensity of the front light emitted from the surface light source 9 in the normal direction of the liquid crystal display element 1 is one with respect to the normal direction. A narrow-field display is performed by irradiating the first illumination light A higher than the intensity of the oblique light emitted in the direction inclined to the direction (left direction) and the opposite direction (right direction), and each of the liquid crystal display elements 1 A display image data signal corresponding to an image signal is applied to the pixel, and the first light emitting element 25a and the two second light emitting elements 25b of the surface light source 9 are simultaneously turned on in synchronization with the application of the display image data signal. Before A wide-field display is performed by irradiating the surface illumination source 9 with the combined illumination light A + B in which the first illumination light A and the second illumination light B in which the intensity of the oblique light is higher than the intensity of the front light are overlapped. Therefore, the display field of view can be controlled to be narrow and wide.

  FIG. 6 is an outgoing ray diagram for the narrow-field display of the liquid crystal display device. At this time, the first light emitting element 25a of the surface light source 9 is turned on, and the surface light source 9 is turned on as shown in FIG. Since the first illumination light A having a strong intensity distribution is irradiated toward the liquid crystal display element 1, it becomes impossible to visually recognize a display image corresponding to the display image data from a direction inclined with respect to the front direction. Therefore, it is possible to perform narrow field display in which the field of view of the display image corresponding to the image signal is limited to the front direction.

  FIG. 7 is an emission ray diagram when the liquid crystal display device performs wide-field display. At this time, the first and second light emitting elements 25a and 25b of the surface light source 9 are turned on simultaneously, and the surface light source 9 Since the combined illumination light A + B having an intensity distribution as shown in FIG. 5C is irradiated toward the liquid crystal display element 1, both from the front direction and from the direction inclined to the left direction and the right direction with respect to the front direction. Wide-field display for observing a display image corresponding to the image signal can be performed.

In addition, in the liquid crystal display device, an incident portion 12 for allowing light to enter an end portion on one edge side of the liquid crystal display element 1 is formed on the opposite side of the liquid crystal display element 1 from the observation side. and along a display element 1 and the flat line plane, along a semicircle around the center portion in the length direction of the incident portion 12 is inclined at the same angle in the radial direction, is incident from the incident part 12 A plurality of arc-shaped diverting surfaces 14 that change the direction of light and exit to the liquid crystal display element 1 are concentrically formed, and face the central portion of the incident portion 12 of the diverting means 10. The first light emitting element 25a that emits light that radiates from the center of curvature O of the arc-shaped turning surface 14 toward the incident portion 12 of the turning means 10, and the turning means 10 Shifted to one end side in the length direction of the incident portion 12 with respect to the central portion of the incident portion 12 And the light that spreads radially from the points P1 and P2 that are shifted with respect to the center of curvature of the arcuate direction change surface 14 to the incident part of the direction changing means. A plurality of second light emitting elements 25b that are emitted toward the surface , and when the first light emitting element 25a is turned on, the intensity of the front light emitted in the normal direction h of the liquid crystal display element 1 is in the normal direction. Irradiating the liquid crystal display element 1 with the first illumination light A having an intensity distribution higher than the intensity of the oblique light emitted in one direction and the direction inclined in the opposite direction to the second light emission By turning on the element 25b, a surface light source 9 for irradiating the liquid crystal display element 1 with the second illumination light B having an intensity distribution in which the intensity of the oblique light is higher than the intensity of the front light is disposed, and the liquid crystal display A display image data corresponding to an image signal is applied to each pixel of the element 1. When the narrow field display is selected according to the field selection signal, the first light emitting element 25a of the surface light source 9 is turned on in synchronization with the application of the display image data signal. Drive means 27 for simultaneously lighting the first light emitting element 25a and the second light emitting element 25b of the surface light source 9 in synchronism with the application of the display image data signal when the visual field display is selected. Therefore, it can be obtained at a much lower cost than a conventional visual field control type liquid crystal display device provided with a liquid crystal element for visual field limitation that is difficult to manufacture.

  Further, the liquid crystal display device is disposed on the surface light source 9 on the exit side of the direction changing unit 10, and out of the light emitted from the direction changing unit 10, with respect to the normal direction h of the liquid crystal display element 1. Further, an anisotropic diffusion plate 26 that diffuses light in a tilted direction is further provided. Therefore, when the narrow-field display is performed, the intensity of the front light from the surface light source 9 is high, and the intensity of the oblique light is high. The first illumination light A having a much lower intensity distribution than the intensity of the front light is irradiated toward the liquid crystal display element 1 to narrow the field of view of the narrow-field display more effectively and Sometimes, from the surface light source 9, the intensity of the emitted light in the direction inclined with respect to the first illumination light A and the normal line direction h of the liquid crystal display element 1 has an intensity distribution close to flat over a wide angle range. 2 illumination light B and the field of view of the wide field display It can be more widely.

  In addition, the liquid crystal display device has an incident end face for making light incident on an end face on one edge side of the liquid crystal display element among the peripheral faces of the plate-like transparent member as the turning means 10 of the surface light source 9. The light exit surface 13 is formed on the plate surface of the transparent member facing the liquid crystal display element 1, and the light exit surface 13 of the light incident from the incident end surface 12 is formed on the opposite plate surface. The liquid crystal display element 1 is inclined from the exit surface 13 by changing the direction of the light incident from the incident end face 12 by tilting at the same angle in the radial direction along a semicircle centering on the central portion of the length direction of 12. Since the light guide plate 11 in which the plurality of arc-shaped diverting surfaces 14 to be emitted to the side are formed concentrically is used, the surface light source 9 can be easily manufactured and the liquid crystal display device can be obtained at lower cost. .

  In the liquid crystal display device of the first embodiment, the intensity of the front light is higher than the intensity of the oblique light due to the lighting of the first light emitting element 25a from the surface light source 9 during narrow field display. The first illumination light of the distribution is irradiated, but in the narrow field display, each pixel of the liquid crystal display element 1 has a display image data signal corresponding to the image signal and a pattern registered in advance. The fixed image data signal corresponding to the fixed image is alternately applied, the first light emitting element 25a of the surface light source 9 is turned on in synchronization with the application of the display image data signal, and the fixed image data signal is applied. Alternatively, the second light emitting element 25b of the surface light source 9 may be turned on in synchronization.

  In the liquid crystal display device of the first embodiment, the first illumination light and the first light-emitting element 25a, 25b are simultaneously turned on from the surface light source 9 during wide-field display. In addition, the second illumination light having an intensity distribution in which the intensity of the oblique light is higher than the intensity of the front light is irradiated at the same time. A wide-narrow-field display is applied to each pixel of the liquid crystal display element 1. By applying a display image data signal corresponding to the image signal and alternately lighting the first light emitting element 25a and the second light emitting element 25b of the surface light source 9 in synchronization with the application of the display image data signal. You may do it.

(Second embodiment)
FIGS. 9 to 13 show a second embodiment of the present invention, and FIG. 9 is a block circuit diagram of a driving means 27 for driving the liquid crystal display element 1 and the surface light source 9.

In the liquid crystal display device of this embodiment, the driving means 27 includes a fixed image data generating unit 28 that generates fixed image data corresponding to a fixed image registered in advance, and first and second image data memories 29 and 30. Display image data corresponding to an image signal supplied from the outside is written into the first memory 29 of the first and second image data memories 29 and 30, and the display image data and the fixed image data are A memory write control unit 31 that selectively writes to the second memory 30 in accordance with a visual field selection signal; and the liquid crystal display element that alternately reads image data written to the first memory 29 and the second memory 30 A memory read control unit 32 to be supplied to the data line driving unit 8a of the display driver 8 mounted on the light source, and a light source drive for selectively lighting the first and second light emitting elements 25a and 25b of the surface light source 9. 33, and the memory write control unit 31 and the memory read controller 32 and the light source driver 33 and a drive control unit 34 controls the scanning line driving unit 8b of the display driver 8, consists.

  When a visual field selection signal for selecting a narrow visual field display is input, the driving means 27 writes the display image data in the first memory 29, reads the fixed image data from the fixed image data generation unit 28, and The fixed image data is written into the second memory 30 and the display image data is read from the first memory 29 in one of two divided periods obtained by dividing one frame for displaying an image of one screen into two. A display image data signal corresponding to the display image data is supplied to each pixel of the liquid crystal display element 1 and supplied to the line driving unit 8a, and the first light emitting element 21a of the surface light source 9 is turned on in synchronization therewith. In the other divided period, the fixed image data is read from the second memory 30, and the fixed image data is supplied to the data line driving unit 8a. Applying a fixed image data signal corresponding to data to each pixel of the liquid crystal display device 1, in synchronization to light the second light emitting element 25b of the surface light source 9 on it.

  The driving means 27 writes the display image data corresponding to the image signal into the first memory 29 and the second memory 30 when the visual field selection signal for selecting the wide visual field display is input, In one of two divided periods obtained by dividing the frame into two, the display image data is read from the first memory 29 and supplied to the data line driving unit 8a, and a display image data signal corresponding to the display image data is supplied to the liquid crystal. The first light-emitting element 25a of the surface light source 9 is turned on in synchronization with each pixel of the display element 1, and the display image data read from the second memory 30 is data line driven in the other divided period. The display image data signal corresponding to the display image data is applied to each pixel of the liquid crystal display element 1, and the second light emitting element 25b of the surface light source 9 is synchronized therewith. To light.

  10A and 10B are driving sequence diagrams of the liquid crystal display element 1 and the surface light source 9 in the field sequential liquid crystal display device. FIG. 10A shows a driving sequence for narrow-field display and FIG. 10B shows a driving sequence for wide-field display. The drive sequence is shown.

In the case of this field sequential liquid crystal display device, one frame is divided into six fields t _{1 to} t _6, and in the case of narrow field display, the one frame is divided into two as shown in FIG. On the other hand, for example, for each of the first to third fields t ₁ , t ₂ , and t ₃ , which are the first half of the divided period, a display image data signal of red unit color and , a unit color display image data signals of green, and the display image data signals of unit colors of blue, sequentially applies the, in synchronization with the application of these display image data signals of each unit color, from the surface light source 9 Then, by selectively lighting the red, green, and blue LEDs of the first light emitting element 25a, the first illumination light A of red, green, and blue having the intensity distribution shown in FIG. The fourth to fourth division periods, which are the latter half of the divided period Each field t _4, each t _5, t ₆ of the each pixel of the liquid crystal display device 1, a unit color fixed image data signal of red, and fixed image data signals of green unit colors, the unit color blue and the fixed image data signals, a sequential application, in synchronization with the application of these fixed image data signals of each unit color, from the surface light source 9, the red of the second light emitting element 25b, green, and blue LED of With the selective lighting, red, green, and blue second illumination lights B having the intensity distribution shown in FIG. 5B are sequentially irradiated.

In the wide-field display, as shown in FIG. 10B, one of the divided periods obtained by dividing the one frame into two, for example, the first to third fields t ₁ and t ₂ that are the first divided period. , every t _3, to each pixel of the liquid crystal display device 1, a unit color display image data signals of red, and the display image data signals of green unit color, and display the image data signals of unit colors of blue, sequentially In the latter half, the first light A of red, green, and blue is sequentially emitted from the surface light source 9 in synchronization with the application of the display image data signal of each unit color. For each of the _{fourth to} sixth fields t ₄ , t ₅ , and t ₆ that are divided periods, a display image data signal of red unit color and a green unit color of each pixel of the liquid crystal display element 1 are displayed. sequentially applies the display image data signals, and the display image data signals of unit colors of blue, and this The second illumination light B of red, green, and blue is sequentially irradiated from the surface light source 9 in synchronization with the application of the display image data signal of each unit color.

  FIG. 10 shows a driving sequence in which the sequential application of the display image data signal of unit colors of red, green, and blue and the sequential application of the fixed image data signal of unit colors of red, green, and blue are alternately performed. However, the present invention is not limited to this, for example, application of a display image data signal of one unit color of red, green, and blue, and application of a fixed image data signal of one unit color of red, green, and blue The first illumination light A of the unit color is irradiated in synchronization with the application of the display image data signal, and the second illumination of the unit color is synchronized with the application of the fixed image data signal. The light B may be irradiated.

  FIG. 11 is a driving sequence diagram of the liquid crystal display element 1 and the surface light source 9 in the liquid crystal display device in which the liquid crystal display element 1 is provided with color filters of three colors of red, green, and blue that face the plurality of pixels. A, (a) shows a driving sequence for narrow-field display, and (b) shows a driving sequence for wide-field display.

For this liquid crystal display device, the one frame is divided into two periods, when the narrow field of view display, as in FIG. 11 (a), for example, the first divided period t _11, the liquid crystal display device A display image data signal of each color of red, green, and blue is applied to each pixel corresponding to each of the red, green, and blue color filters, and the surface light source 9 is synchronized with the application of the display image data signal. from the lighting of the first light-emitting element 25a, is irradiated with white color first illumination light a of the intensity distribution of FIG. 5 (a), the second divided period t _12, each of the liquid crystal display device 1 A fixed image data signal of each color of red, green, and blue is applied to the pixel, and the second light emitting element 25b is turned on from the surface light source 9 in synchronization with the application of the fixed image data signal. (b) white color second illumination light intensity distribution is irradiated for.

Further, when the wide-field display, as shown in FIG. 11 (b), the example in the first divided period t _11, the liquid crystal display device 1, red, green, and each pixel corresponding to the blue color filter, red , green, is applied to each color display image data signals of blue, in synchronism with application of the display image data signals, is irradiated with first illumination light a of the white color from the surface light source 9, second divided period Similarly to t _12, the each pixel of the liquid crystal display device 1, the red, green, and applying a respective color display image data signals of blue, in synchronism with application of the display image data signals, from the surface light source 9 and irradiates the second illumination light B of the white color.

  That is, the liquid crystal display device of this embodiment alternately displays an image corresponding to the display image data, and an image corresponding to the image data selected from either the display image data or the fixed image data. The display image data signal is applied to each pixel of the liquid crystal display element 1, and the intensity of the front light emitted from the surface light source 9 in the normal direction h of the liquid crystal display element 1 is synchronized with the display image data signal. Irradiating with the first illumination light A having an intensity distribution higher than the intensity of the oblique light emitted in one direction (left direction) and the opposite direction (right direction) with respect to the normal direction h. To display an image corresponding to the display image data, apply the selected image data signal to each pixel of the liquid crystal display element 1, and synchronize with it to increase the intensity of the oblique light from the surface light source 9. Image corresponding to the image data selected by irradiating the illumination light B second high intensity distributions than the intensity of the Show.

  Therefore, the display corresponding to the display image data is a display having a luminance distribution peak in the front direction (direction near the normal line of the liquid crystal display element 1), that is, a display in which the field of view is limited to the front direction. The display corresponding to the selected image data is a display having a luminance distribution peak in a direction inclined leftward and rightward with respect to the front direction, that is, the field of view is leftward with respect to the frontal direction and The display is limited to the direction tilted to the right.

  Therefore, when the fixed image data is selected as the image data, an image corresponding to the display image data and an image corresponding to the fixed image data are alternately displayed, and the fixed image data Is data corresponding to a fixed image of a pre-registered pattern, so that a display image corresponding to the display image data cannot be viewed from a direction inclined with respect to the front direction, and the display thereof Since the image is hidden by a fixed image having a pattern corresponding to the fixed image data viewed from a direction inclined with respect to the front direction, the display image cannot be seen at all, and the field of view of the display image corresponding to the image signal is viewed from the front. A narrow-field display limited to the direction can be performed.

  FIG. 12 shows an example of the display viewed from the front direction and the display viewed from the direction tilted leftward and rightward in the narrow-field display. Here, a display image corresponding to the display image data is shown. And a checkered fixed image are alternately displayed.

  The checkered fixed image may be an image of a pattern in which square patterns of a plurality of colors of red, green, blue, or mixed colors of yellow, magenta, cyan, and black are alternately arranged in a row direction and a column direction. Alternatively, an image of a pattern in which white and black rectangular patterns of mixed colors of red, green, and blue are alternately arranged in a row direction and a column direction may be used. Furthermore, the fixed image is not limited to a checkered pattern, and may be a stripe pattern, a mark, a character, or the like.

  On the other hand, when display image data is selected as the image data, images corresponding to the display image data are alternately displayed and tilted leftward and rightward relative to the front direction from the front direction. It is possible to perform wide-field display that allows a display image corresponding to an image signal to be observed from the direction.

  FIG. 13 shows an example of the display viewed from the front direction and the display viewed from the direction inclined leftward and rightward in the wide-field display.

Thus, in the liquid crystal display device of this embodiment, when the narrow-field display is selected by the driving unit 27, the display image data signal corresponding to the image signal is displayed on each pixel of the liquid crystal display element 1. A fixed image data signal corresponding to a fixed image of a pre-registered pattern is alternately applied, and the first light emitting element 25a of the surface light source 9 is turned on in synchronization with the application of the display image data signal, and the fixed Since the second light emitting element 25b of the surface light source 9 is turned on in synchronization with the application of the image data signal, the display image corresponding to the display image data is displayed from the direction inclined with respect to the front direction. since the viewing can not be, yet invisible hidden by a fixed image of the pattern that displays images corresponding to the fixed image data, and more effective viewing of the display image corresponding to the image signal Can be performed to narrow view display is limited to the front direction.

(Third embodiment)
FIGS. 14 and 15 show a third embodiment of the present invention. FIG. 14 is a plan view from the emission side of the surface light source 9a arranged opposite to the surface of the liquid crystal display element 1 opposite to the observation side. FIG. 15 is a sectional view in which hatching along the line XV-XV in FIG. 14 is omitted.

  In this embodiment, the surface light source 9a is one of the edges of the liquid crystal display element 1 in the periphery of a plate-shaped transparent member such as an acrylic resin plate, for example, one of the vertical directions of the screen of the liquid crystal display element 1. An incident end face (incident part) 17 for allowing light to enter is formed on an end face on the edge side (upper edge side in the drawing), and the length of the incident end face 17 is formed on the plate surface of the transparent member facing the liquid crystal display element 1. A plurality of arc-shaped changes which are inclined at the same angle in the radial direction along a semicircle centering on the center of the direction and change the direction of light incident from the incident end face 17 and are emitted to the liquid crystal display element 1 side. A light guide plate in which a direction surface 18 is formed concentrically and a reflection surface 19 that reflects light incident from the incident end surface 17 toward the plurality of arc-shaped direction change surfaces 18 is formed on the opposite plate surface. 16 and the light guide plate 1 disposed on the light exit side of the light guide plate 16. Is formed in an arc shape along a semicircle centered on a point corresponding to the center of curvature of the arc-shaped diverting surface 18 of the light guide plate 16, and a plurality of arc-shaped diverting surfaces of the light guide plate 16 A plurality of arc-shaped prisms 23 that refract the emitted light from 18 in a direction in which the angle with respect to the normal direction h of the liquid crystal display element 1 becomes smaller are formed concentrically, and on the surface facing the liquid crystal display element 1, The light guide plate 16 of the direction change unit 10a includes a direction change unit 10a including a prism sheet 21 on which an output surface 24 for emitting light refracted by the plurality of arc-shaped prisms 23 to the liquid crystal display element 1 side is formed. A first light emitting element 25 a that emits light radially spreading from the center of curvature of the arc-shaped turning surface 18 toward the incident end surface 17 of the light guide plate 16 is disposed so as to face the central portion of the incident end surface 17. The light guide plate 1 The center of curvature of the arc-shaped turning surface 18 is opposed to a position shifted to one end side in the length direction of the incident end surface 17 and a position shifted to the other end side with respect to the central portion of the incident end surface 17. A plurality (two in this embodiment) of the second light emitting elements 25b for emitting light spreading radially from the point shifted with respect to the incident end face 17 of the light guide plate 16 are arranged.

  Each of the plurality of arc-shaped diverting surfaces 18 of the light guide plate 16 is an inclined surface that is inclined at a predetermined angle in a direction opposite to the reflecting surface 19 toward the center of the semicircle. They are formed concentrically at a pitch that is about the same as or smaller than the pixel pitch of the display element 1.

  Further, each of the plurality of arc-shaped prisms 23 of the prism sheet 21 has an isosceles triangular cross-sectional shape, and is concentric with a pitch smaller than the pitch of the plurality of arc-shaped diverting surfaces 18 of the light guide plate 16. It is formed in a shape.

  In this embodiment, the reflection surface 19 of the light guide plate 16 is formed by providing a reflection film 20 on the plate surface of the light guide plate 16. The reflection surface 19 of the light guide plate 16 is formed by the incident end surface. It is good also as an internal reflection surface which totally reflects the incident light from 17 in the interface of the board surface of the light-guide plate 16, and external air.

The surface light source 9a changes the direction of the light incident on the light guide plate 16 of the diverting means 10a from the incident end surface 17 by the plurality of arc-shaped diverting surfaces 18 as indicated by arrows in FIG. The light is emitted from the light guide plate 16, and the light is refracted by the plurality of arc-shaped prisms 23 of the prism sheet 21 and emitted from the emission surface 24 of the prism sheet 21 to the liquid crystal display element 1 side. The inclination angle of the plurality of arc-shaped diverting surfaces 18 of the light guide plate 16 and the angle of inclination of the two inclined surfaces of the plurality of arc-shaped prisms 23 of the prism sheet 21 are the arc-shaped diverting surfaces of the light guide plate 16. when light is incident radiating from the center of curvature of 18 direction along the plate surface and a flat line plane of the light guide plate 16, from the exit surface 24 of the prism sheet 21, the law of the liquid crystal display device 1 Along the line direction h It is set so as to emit light having an intensity distribution which exists a peak of emission intensity in the direction.

  In the surface light source 9a, when the first light emitting element 25a is turned on, the intensity of the front light emitted in the normal direction h of the liquid crystal display element 1 is in one direction and the opposite direction to the normal direction h. The first illumination light having an intensity distribution higher than the intensity of the oblique light emitted in the inclined direction is irradiated toward the liquid crystal display element 1, and the intensity of the oblique light is turned on by turning on the two second light emitting elements 25 b. Irradiates the liquid crystal display element 1 with the second illumination light having an intensity distribution higher than the intensity of the front light.

  Therefore, the surface light source 9a is arranged on the side opposite to the observation side of the liquid crystal display element 1, and an image signal is supplied to each pixel of the liquid crystal display element 1 by the driving means 27 of the first or second embodiment described above. When the narrow-field display is selected according to the visual field selection signal, the first light emitting element 25a of the surface light source 9a is synchronized with the application of the display image data signal. When the wide-field display is selected, the first light emitting element 25a and the second light emitting element 25b of the surface light source 9a are turned on simultaneously or alternately in synchronization with the application of the display image data signal. By doing so, the display field of view can be controlled to be narrow and wide.

  In the liquid crystal display device of this embodiment, on the side opposite to the viewing side of the liquid crystal display element 1, the turning means 10a comprising the light guide plate 16 and the prism sheet 21 and the first and second light emitting elements 25a. , 25b, and the liquid crystal display element 1 and the driving means 27 for driving the surface light source 9a are provided. Compared with the visual field control type liquid crystal display device, it can be obtained at a much lower cost.

  Also in this embodiment, the surface light source 9a is disposed on the emission side of the direction changing means 10a, and out of the light emitted from the direction changing means 10a, the normal direction h of the liquid crystal display element 1 It is preferable to further include an anisotropic diffusion plate that diffuses light in a tilted direction. By doing so, the field of view of the narrow-field display can be narrowed more effectively and the field of view of the wide-field display can be reduced. Can be wider.

(Other embodiments)
In the liquid crystal display device of the present invention, the surface light source changing means disposed on the opposite side of the liquid crystal display element 1 from the observation side is the light guide plate 11 of the first embodiment or the guide of the third embodiment. is not limited to the optical plate 16 and the prism sheet 21, and the incident portion through which light enters the end portion of the one edge side of the liquid crystal display device 1 is formed, along a liquid crystal display element 1 and the flat line plane, A plurality of light beams that are inclined at the same angle in the radial direction along a semicircle centered on the central portion in the length direction of the incident portion, and change the direction of light incident from the incident portion and are emitted to the liquid crystal display element side. As long as the arcuate direction change surface is formed concentrically, another configuration may be used.

  Further, the surface light sources 9, 9a of the above-described embodiment include one first light emitting element 25a and two second light emitting elements 25b, and the second light emitting element 25b includes the diverting means. A plurality of positions sequentially shifted toward one end side in the length direction of the incident part 12 and a plurality of positions sequentially shifted toward the other end side in the length direction of the incident part 12. May be arranged to face each other.

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal display element, 1a ... Screen area | region, 9, 9a ... Surface light source, 10, 10a ... Diverting means, 11, 16 ... Light guide plate, 12, 17 ... Incidence end surface (incident part), 13 ... Output surface, 14 , 18 ... arc-shaped turning surface, 19 ... reflecting surface, 21 ... prism sheet, 23 ... arc-shaped prism, 24 ... exit surface, 25a ... first light emitting element, 25b ... second light emitting element, 27 ... control means .

Claims (14)

A liquid crystal display element in which a plurality of pixels are arranged in a matrix;
A light guide plate disposed so as to face the liquid crystal display element and having different angles indicating the peak value of the emitted light emitted from the surface facing the liquid crystal display element according to the incident position of the light incident from a predetermined end face When,
The angle indicating the peak value of the emitted light emitted from the surface of the light guide plate facing the liquid crystal display element is disposed at a position perpendicular to the emission surface of the emitted light, and toward the light guide plate A first light emitting element that emits light;
The angle indicating the peak value of the emitted light emitted from the surface facing the liquid crystal display element of the light guide plate is disposed at a position where the angle is inclined with respect to the emission surface of the emitted light, and toward the light guide plate A second light emitting element that emits light;
A first memory for storing image data sequentially supplied from the outside;
A second memory for storing pre-registered fixed image data;
An image to be displayed on the liquid crystal display element is time-divided between an image based on the image data stored in the first memory and an image based on the image data stored in the second memory. A display control unit that alternately switches and outputs, and
A light source control unit that switches a light emitting element to emit light between the first light emitting element and the second light emitting element in synchronization with an image switching timing by the display control unit;
Equipped with a,
When the display control unit causes the liquid crystal display element to output an image based on the image data stored in the first memory, the light source control unit causes the first light emitting element to emit light and the second light emitting element to emit light. The light emitting element does not emit light,
When the display control unit causes the liquid crystal display element to output an image based on the image data stored in the second memory, the light source control unit causes the second light-emitting element to emit light and the first light-emitting element to emit light. Do not make the light emitting element emit light,
A liquid crystal display device characterized by the above. At a position where the angle indicating the peak value of the light emitted from the surface of the light guide plate facing the liquid crystal display element is symmetrical with respect to the angle indicating the peak value of the light from the second light emitting element. A third light emitting element that is disposed and emits light toward the light guide plate;
The light source control unit controls the third light emitting element in the same manner as the second light emitting element;
The liquid crystal display device according to claim 1 . Fixed image data registered in advance in the second memory when the narrow viewing angle display is selected, and image data sequentially supplied from the outside to the second memory when the wide viewing angle display is selected A control unit for writing
The liquid crystal display device according to claim 1 or 2 . The second light emitting element is disposed at a position where an angle indicating the peak value is an angle inclined by 20 ° with respect to a normal line of the emission surface.
The liquid crystal display device according to any one of claims 1 to 3, characterized in that. The fixed image data corresponds to a mosaic image,
The liquid crystal display device according to any one of claims 1 to 4, characterized in that. The peak value of light from the first light emitting element is greater than the peak value of light from the second light emitting element;
The liquid crystal display device according to any one of claims 1 to 5, characterized in that. The image data and the fixed image data are each composed of a red component, a green component, and a blue component,
2. The liquid crystal display device according to claim 1, wherein the color components are switched in a time division manner and output to the display panel. Each of the two light emitting elements includes a red LED, a green LED, and a blue LED,
The liquid crystal display device according to claim 7 , wherein an LED having a color corresponding to a color component output to the display panel is turned on and the other LEDs are turned off for the light emitting element in the light emitting state. The image data and the fixed image data are red, green, and blue color data corresponding to the red, green, and blue pixels of the display panel, respectively.
2. The liquid crystal display device according to claim 1, wherein the respective components are switched in a time division manner and output to the display panel. Each of the two light emitting elements is a white LED,
10. The liquid crystal display device according to claim 9 , wherein a white LED corresponding to each component output to the display panel is turned on and the other white LEDs are turned off for the light emitting element in the light emitting state. . Each of the two light emitting elements includes a red LED, a green LED, and a blue LED,
The light emitting element of the light-emitting state, the red LED corresponding to each component to be output to the display panel, to claim 9, characterized in that turns off the other LED with simultaneous turning on the green LED and blue LED The liquid crystal display device described. The two light emitting elements, a liquid crystal display device according to any one of claims 1 to 11, characterized in that it is arranged so as to emit light toward the same end surface of the light guide plate. The said two light emitting elements are arrange | positioned so that the emission direction of the light inject | emitted toward the said light-guide plate may become a mutually parallel direction, The one of Claim 1 thru | or 12 characterized by the above-mentioned. Liquid crystal display device. The liquid crystal display device according to any one of claims 1 to 13 wherein the two light emitting elements, characterized in that it is disposed adjacent.

Images