JP6501690B2 - Display device - Google Patents

Description

  The present invention relates to a display device.

  An edge light type light source device mounted on a display device partially emits light from a light guide plate using white light guided to the light guide plate for displaying an image with high contrast and reducing power consumption. It is possible to perform partial drive to emit light. With respect to a light source device mounted on such a display device, a technique has been proposed for improving the motion blur of the display device without increasing the power consumption.

JP, 2014-102295, A

  The present invention provides a display device that reduces image quality degradation.

According to one aspect of the present invention, an image display panel in which display scanning is sequentially performed in a first direction, a light source emitting light, and a back surface of the image display panel are disposed opposite to the image display panel The light is incident from the side of the surface and is guided in a second direction opposite to the first direction, and the light is transmitted or transmitted in a scattering state in which the light is scattered. The first direction so as not to overlap temporally with a light source device including a light guide having a plurality of regions where the controllable light modulation layer is divided in a direction crossing the second direction; Within the scattering control time of the light modulation layer corresponding to each of the regions sequentially assigned to each of the regions toward each of the regions according to the intensity of the light emitted from each of the regions to the image display panel. The corresponding side of each region of the light modulation layer And a control device for controlling the length scattering state of the time corresponding to a distance from, said plurality of regions, the second region than the first region the first region adjacent to the side surface And the controller is configured to control the light modulation layer in a scattering state corresponding to the second area in the scattering control time of the second area at an idle time in the first area. The display device can control the corresponding light modulation layer in a scattering state, and uniformly raise the upper limit of the intensity of the light that can be emitted from each region to the image display panel .

Further, according to one aspect of the present invention, an image display panel, a light source emitting light, and the light which is disposed on the back of the image display panel and which receives the light from the side facing the image display panel A light source comprising: a light guide which can be controlled to be in a transmission state for transmitting light or in a scattering state for scattering the light, and the light modulation layer is disposed in a plurality of areas divided in a direction intersecting the traveling direction of the light. Each device according to the intensity of the light emitted from each area to the image display panel within the scattering control time of the light modulation layer corresponding to each area set so as not to overlap in time. The light modulation layer corresponding to each area is controlled to the scattering state by the length of time according to the distance from the side surface of the area, and the light modulation layer corresponding to each area within the scattering control time allocated to each area Scattering of the light modulation layer Has a control device for stopping the light emission of the light from the light source to the control and non time, a plurality of regions, the second than the first region the first region adjacent to the side surface And the first control unit is configured to control the light modulation layer in a scattering state corresponding to the second region within the scattering control time of the second region. The display device can control the light modulation layer corresponding to a region to be in a scattering state, and uniformly raise the upper limit of the intensity of the light that can be emitted from each region to the image display panel .

It is a figure which shows the structural example of the display apparatus of 1st Embodiment. It is a figure showing the example of hardware constitutions of the display of a 2nd embodiment. It is a top view which shows the structural example of the planar light source device of 2nd Embodiment. It is sectional drawing which shows the structural example of the planar light source device of 2nd Embodiment. It is a top view which shows the structural example of the upper electrode of the light guide of 2nd Embodiment. It is a top view which shows the structural example of the lower electrode of the light guide of 2nd Embodiment. It is a schematic diagram explaining the effect | action of the light modulation layer of 2nd Embodiment. It is a figure which shows an example of the partial drive of the planar light source device of 2nd Embodiment. It is a figure which shows the function structural example contained in the display apparatus of 2nd Embodiment. It is a figure which shows the function structural example of the signal processing part contained in the display apparatus of 2nd Embodiment. It is a figure which shows the drive pattern of the planar light source device of 2nd Embodiment. It is a figure which shows the drive pattern of the planar light source device of 3rd Embodiment. It is a figure which shows the drive pattern of the planar light source device of 4th Embodiment. It is a figure which shows the drive pattern of the planar light source device of 5th Embodiment. It is a figure which shows the modification of the drive pattern of the planar light source device of 5th Embodiment. It is a figure which shows the drive pattern of the planar light source device of 6th Embodiment. It is a figure which shows the drive pattern of the planar light source device of 7th Embodiment.

Hereinafter, embodiments will be described with reference to the drawings.
The disclosure is merely an example, and it is naturally included within the scope of the present invention as to what can be easily conceived of by those skilled in the art as to appropriate changes while maintaining the gist of the invention. In addition, the drawings may be schematically represented as to the width, thickness, shape, etc. of each part in comparison with the embodiment in order to clarify the description, but this is merely an example, and the interpretation of the present invention is not limited. It is not limited.
In the present specification and each drawing, the same reference numerals are given to the same elements as those described above with reference to the drawings, and the detailed description may be appropriately omitted.

First Embodiment
The display device of the first embodiment will be described with reference to FIG. FIG. 1 is a view showing a configuration example of a display device of the first embodiment.

The display device 1 includes an image display panel 10, a light source device 20, and a control device 30.
The image display panel 10 displays a predetermined image. The image display panel 10 sequentially performs display scanning in the first direction.
The light source device 20 emits light to the image display panel 10. The light source device 20 includes a light source 21 and a light guide 22. The light source 21 emits light.

  The light guide 22 is disposed on the back surface of the image display panel 10, and the light emitted from the light source 21 is incident from the side surface 23 of the surface facing the image display panel 10, and a second direction opposite to the first direction. While guiding the light toward the image display panel 10. The light guide 22 has a plurality of regions (regions 22a, 22b, 22c, 22d, 22e, 22f) divided in a direction intersecting the second direction. In each region, a light modulation layer that can be controlled to be in a transmitting state that transmits light or in a scattering state that scatters light is disposed.

  The light modulation layer is, for example, a polymer dispersed liquid crystal layer, and is controlled to a transmission state or a scattering state by generating an electric field. Therefore, when the light modulation layer corresponding to the region is in the transmission state, light passes through the region and travels to the adjacent region (second direction). On the other hand, when the light modulation layer corresponding to the area is in the scattering state, light is scattered by the light modulation layer, and part of the scattered light is emitted from the area to the image display panel 10.

  The control device 30 controls the light source device 20. The control device 30 generates an electric field in the light modulation layer corresponding to each area at the scattering control time of the light modulation layer corresponding to each area, and controls the light modulation layer corresponding to each area to the scattering state. The scattering control time of the light modulation layer corresponding to each region is sequentially assigned toward the first direction so as not to overlap in time. That is, the control device 30 controls the light modulation layers corresponding to the respective regions in the scattering state in order so as not to overlap temporally (the area including the light modulation layer in the scattering state is only one place) .

  As described above, the control device 30 controls the light modulation layer corresponding to each area to the scattering state during the scattering control time of the light modulation layer corresponding to each area, whereby the light source device 20 controls the light modulation layer to the scattering state. It drives by the partial drive which radiate | emits light with respect to the image display panel 10 in order from the area | region which was done.

  Here, a specific example in the case of partially driving the light source device 20 will be described in which the control device 30 controls the light modulation layer corresponding to each region to the scattering state at the scattering control time. For example, when the control device 30 generates an electric field for the light modulation layer corresponding to the region 22b to control in the scattering state, the light emitted by the light source 21 enters the light guide 22 from the side surface 23, and the light modulation is performed. The layer passes through the area 22a which is controlled to the transmission state. The light emitted from the light source 21 is scattered by the light modulation layer corresponding to the area 22b controlled to the scattering state, and the light directed to the image display panel 10 among the scattered light is transmitted from the area 22b to the image display panel 10 Emit against.

  On the other hand, when the control device 30 generates an electric field for the light modulation layer corresponding to the region 22e to control in the scattering state, the light emitted by the light source 21 enters the light guide 22 from the side surface 23, and the light modulation is performed. The layers pass through the regions 22a, 22b, 22c, 22d which are controlled in the transmission state. The light emitted from the light source 21 is scattered by the light modulation layer corresponding to the area 22e controlled to the scattering state, and the light directed to the image display panel 10 among the scattered light is transmitted from the area 22e to the image display panel 10 Emit against.

  Thus, as the distance from the side surface 23 of the area from which light is emitted to the image display panel 10 increases, the number of areas through which the light emitted from the light source 21 passes before exiting from the light guide 22 Will increase. By the way, it is known that light may change (attenuate) in intensity when passing through an area. The light intensity is, for example, the brightness, lightness, etc. of the light.

  Therefore, when the control device 30 partially drives the light source device 20 under the same drive condition in the entire region, the intensity of light emitted from the light guide 22 may be shifted for each region. Therefore, control device 30 is desired to change the control mode for each area.

  Therefore, in accordance with the intensity of light emitted from each area to the image display panel within the scattering control time of the light modulation layer corresponding to each area, control device 30 selects each light modulation layer corresponding to each area. The length of time according to the distance from the side surface 23 of the region is controlled to the scattering state.

  Specifically, when light having a predetermined intensity is emitted from each area, control device 30 moves the light modulation layer into the scattering state as the area including the light modulation layer to be controlled to the scattering state gets farther from side surface 23. Control the length of time to generate the electric field so that the time to grow is long.

  Thus, according to the intensity of light emitted from each area to the image display panel, the light modulation layer corresponding to each area is controlled to be in a time-scattered state according to the distance from the side surface 23 of each area. Thus, the control device 30 can suppress the deviation of the light intensity between the regions.

  Accordingly, when the light source device 20 is partially driven, the control device 30 can prevent the intensity of light emitted from each region from deviating from the desired intensity. As a result, the display device 1 can reduce the deterioration of the image quality.

Second Embodiment
In the second embodiment, the display device of the first embodiment will be more specifically described.
First, an example of the hardware configuration of the display device according to the second embodiment will be described with reference to FIG. FIG. 2 is a diagram showing an example of the hardware configuration of the display device of the second embodiment.

  The display device 100 is an embodiment of the display device 1 shown in FIG. 1, and the entire device is controlled by the control unit 100a.

  The control unit 100a can output and input signals to and from a central processing unit (CPU) 100a1, a random access memory (RAM) 100a2, a read only memory (ROM) 100a3, and a plurality of peripheral devices via the bus 100f. It is connected to the.

  The CPU 100a1 controls the entire display device 100 based on OS (Operating System) programs and application programs stored in the ROM 100a3 and various data developed in the RAM 100a2. At the time of process execution, the program may be operated by an OS program or application program temporarily stored in the RAM 100a2.

  The RAM 100a2 is used as a main storage device of the control unit 100a. The RAM 100a2 temporarily stores at least part of an OS program and application programs to be executed by the CPU 100a1. The RAM 100a2 also stores various data necessary for processing by the CPU 100a1.

  The ROM 100 a 3 is a read-only semiconductor storage device, and stores an OS program, an application program, and fixed data that is not to be rewritten. Also, instead of the ROM 100a3 or in addition to the ROM 100a3, a semiconductor storage device such as a flash memory can be used as a secondary storage device.

  The peripheral devices connected to the bus 100 f include a display driver IC (Integrated Circuit) 100 b, an LED (Light Emitting Diode) driver IC 100 c, an input / output interface 100 d, and a communication interface 100 e.

  An image display panel 200 is connected to the display driver IC 100b. The display driver IC 100 b displays an image on the image display panel 200 by outputting an output signal to the image display panel 200. The display driver IC 100b can also realize at least a part of the function of an image display panel drive unit described later.

  The planar light source device 300 (one embodiment of the light source device 20 of the first embodiment) is connected to the LED driver IC 100c. The LED driver IC 100 c drives the light source according to a light source control signal described later, and controls the luminance of the light emitted from the planar light source device 300. The LED driver IC 100c implements at least a part of the function of a planar light source device drive unit (one embodiment of the control device 30 of the first embodiment) described later.

  An input device for inputting a user's instruction is connected to the input / output interface 100d. For example, input devices such as a keyboard, a mouse used as a pointing device, and a touch panel are connected. The input / output interface 100d transmits the signal sent from the input device to the CPU 100a1.

  The communication interface 100 e is connected to the network 1000. The communication interface 100 e transmits and receives data to and from another computer or communication device via the network 1000.

  The processing function of the present embodiment can be realized by the hardware configuration as described above.

  Next, a configuration example of the planar light source device 300 will be described using FIGS. 3 to 6. FIG. 3 is a plan view showing a configuration example of a planar light source device of the second embodiment, and FIG. 4 is a cross-sectional view showing a configuration example of the planar light source device of the second embodiment. FIG. 5 is a plan view showing a configuration example of the upper electrode of the light guide according to the second embodiment. FIG. 6 is a plan view showing a configuration example of the lower electrode of the light guide according to the second embodiment.

  The planar light source device 300 is disposed on the back side of the image display panel 200, and emits light on the back side of the image display panel 200. The planar light source device 300 includes a light guide 310, and a side light source 302 in which light sources 303a to 303j are arranged at positions facing at least one side surface of the light guide 310 as an incident surface E. Have.

  The light sources 303a to 303j of the sidelight light source 302 are light emitting diodes (LEDs), and are configured so that the current or the PWM value (duty ratio or the like) can be controlled independently of each other. The light sources 303a to 303j (FIG. 3) are arranged along one side surface of the light guide 310, and when the direction in which the light sources 303a to 303j are arranged is a light source array direction LY, an incident direction LX orthogonal to the light source array direction LY. The light from the light sources 303a to 303j enters the light guide 310 from the incident surface E toward the light source. The light sources 303a to 303j are not limited to light emitting diodes, and semiconductor lasers can also be used.

  The light guide 310 guides the light from the side light source 302 (light sources 303 a to 303 j) disposed on the side surface to the upper surface of the light guide 310. The light guide 310 has a shape corresponding to the image display panel 200 disposed on the upper surface side of the planar light source device 300. The light guide 310 is composed of a plurality of regions divided in a direction intersecting the traveling direction of light. In the present embodiment, numbers from (1) to (6) are assigned in order from the region on the side surface opposite to the side surface on which the side light source 302 is disposed.

  The planar light source device drive unit 500 is connected to the side light source 302 (light sources 303 a to 303 j) and the light guide 310 so that signals can be transmitted. The planar light source device drive unit 500 is a partial drive planar light source device that emits light sequentially from the exit surface (the surface facing the image display panel 200) of the regions (1) to (6) of the light guide 310. Drive 300. The partial drive will be described in detail later with reference to FIG.

  Here, the planar light source device 300 will be more specifically described using FIG. 4. The planar light source device 300 includes a side light source 302, a light guide 310, and a reflection sheet 330 provided on the back surface of the light guide 310 (the surface opposite to the surface facing the image display panel 200). Configured

  The reflection sheet 330 is for returning the light leaked from the back surface (the lower surface in FIG. 4) of the light guide 310 to the light guide 310 side, and has, for example, functions such as reflection, diffusion, and scattering. . Thereby, the light incident from the sidelight light source 302 can be efficiently used, and contributes to the improvement of the luminance of the light emitted from the light emission surface of the planar light source device 300. For the reflective sheet 330, for example, foamed PET (polyethylene terephthalate), a silver vapor deposited film, a multilayer reflective film, white PET, or the like can be used. In addition, in FIG. 4, the reflective sheet 330 is laminated | stacked via an air layer, and is not closely_contact | adhered optically.

  In the light guide 310, a transparent substrate 311, an upper electrode 312, an alignment film 313, a light modulation layer 314 and a spacer 315, an alignment film 316, a lower electrode 317, and a transparent substrate 318 are sequentially arranged. is there.

  The transparent substrates 311 and 318 support the light modulation layer 314, and are generally made of a substrate transparent to visible light, such as a glass plate or a plastic film.

  The upper electrode 312 is a transparent electrode provided on the surface of the transparent substrate 311 facing the transparent substrate 318. Here, the upper electrode 312 will be described with reference to FIG. For example, as shown in FIG. 5, the upper electrodes 312 are provided in a strip shape extending in a direction parallel to the extending direction of the side light source 302 corresponding to the respective regions in the plane.

  The upper electrodes 312 are connected to different wires 312 a for each of the upper electrodes 312 corresponding to the regions (1) to (6). The upper electrode 312 is electrically connected by the wire 312a connected thereto. In the upper electrode 312, a voltage corresponding to a signal from the planar light source device driving unit 500 is applied to the connection terminal 312b at the end of the wiring 312a. As a result, the upper electrode 312 is controlled for each upper electrode 312 corresponding to the regions (1) to (6). Returning to FIG. 4, the description will be continued.

  The lower electrode 317 is provided on the transparent substrate 318 so as to face the transparent substrate 311. Here, the lower electrode 317 will be described with reference to FIG. The lower electrode 317 is in the shape of a strip extending parallel to the in-plane region and extending to face the upper electrode 312, as shown in FIG. The lower electrode 317 is electrically connected by the connected wire 317a, and a voltage according to the signal from the planar light source device driving unit 500 is applied to the connection terminal 317b at the end of the wire 317a. In the light modulation layer corresponding to each region, an electric field corresponding to a voltage difference between the upper electrode 312 and the lower electrode 317 corresponding to each region (hereinafter, a voltage difference between the electrodes) is generated. The shapes of the upper electrode 312 and the lower electrode 317 are not limited to the above shapes as long as they can generate an electric field in the light modulation layer corresponding to the region independently for each region. Returning to FIG. 4, the description will be continued.

  The alignment films 313 and 316 align, for example, liquid crystal molecules 314 b used for the light modulation layer 314. As the type of alignment film, for example, there are an alignment film for vertical and an alignment film for horizontal.

  The spacer 315 controls the distance between the transparent substrates 311 and 318. The spacer 315 is formed of a transparent material that transmits light. The spacer 315 is formed in a region not overlapping with the upper electrode 312 and the lower electrode 317. The spacer 315 transmits light more than the light modulation layer 314 in the transmission state. Therefore, the provision of the spacer 315 can suppress the attenuation (the decrease in luminance) of the light traveling in the light guide 310 as compared to the case where the light modulation layer 314 is provided on the entire surface. The light guide 310 may not have the spacer 315.

  The light modulation layer 314 is a polymer dispersed liquid crystal layer, and is formed of a composite layer including a liquid crystalline monomer 314 a and a plurality of liquid crystalline molecules 314 b dispersed in the liquid crystalline monomer 314 a. The liquid crystalline monomer 314a and the liquid crystalline molecule 314b have the same optical anisotropy.

  The operation of such a light modulation layer 314 will be described with reference to FIG. FIG. 7 is a schematic view for explaining the function of the light modulation layer of the second embodiment. The optical axes Ax1 and Ax2 described in FIGS. 7A and 7B are lines parallel to the traveling direction of the light beam such that the refractive index has a single value regardless of the polarization direction. The liquid crystal monomers 314a and the liquid crystal molecules 314b in (A) and (B) are schematically shown, respectively.

  First, a case where there is no voltage difference between electrodes corresponding to a region and no electric field is generated in the light modulation layer 314 in the region will be described with reference to FIG. 7A.

  In this case, the optical axis Ax1 of the liquid crystalline monomer 314a and the optical axis Ax2 of the liquid crystalline molecules 314b are aligned (parallel) with each other (FIG. 7A). Further, the directions of the optical axis Ax1 and the optical axis Ax2 do not always have to be completely coincident with each other, and the direction of the optical axis Ax1 and the direction of the optical axis Ax2 may be somewhat shifted due to, for example, a manufacturing error .

When no electric field is generated in the light modulation layer, the optical axis Ax2 of the liquid crystal molecules 314b is orthogonal to the surfaces of the transparent substrates 311 and 318. On the other hand, as shown in FIGS. 7A and 7B, the optical axis Ax1 of the liquid crystalline monomer 314a is the transparent substrate 311 or 318, regardless of the presence or absence of the electric field of the light modulation layer 314. The structure is orthogonal to the surface. The optical axis Ax2 does not always have to be completely orthogonal to the surfaces of the transparent substrates 311 and 318. For example, even if it intersects the surfaces of the transparent substrates 311 and 318 at an angle other than 90 degrees due to manufacturing errors Good. In addition, the optical axis Ax1 does not always have to be completely orthogonal to the surfaces of the transparent substrates 311 and 318. For example, even if it intersects the surfaces of the transparent substrates 311 and 318 at an angle other than 90 degrees due to manufacturing error or the like. Good.

  Here, it is preferable that the ordinary light refractive indexes of the liquid crystalline monomer 314a and the liquid crystalline molecules 314b be equal to each other, and the extraordinary refractive indexes of the liquid crystalline monomer 314a and the liquid crystalline molecules 314 b be equal to each other. In this case, for example, when there is no voltage difference between the electrodes and no electric field is generated in the light modulation layer 314, as shown in FIG. 7A, there is almost no refractive index difference in all directions, and high transparency Is obtained. Thus, for example, light L1 directed to the front (upper side in FIG. 7) and light L2 and light L3 directed to the oblique (diagonally upward in FIG. 7) direction are not scattered in the light modulation layer 314 and light modulation is performed. Permeate layer 314.

  Next, with respect to the light modulation layer 314, a case where an electric field is generated in the light modulation layer 314 by a voltage difference between electrodes (corresponding to an arbitrary region of the light emitting surface) will be described.

  In this case, the optical axis Ax2 is inclined by an electric field generated in the light modulation layer 314 due to the voltage difference between the electrodes of the liquid crystalline molecules 314b, so the optical axis Ax1 of the liquid crystalline monomer 314a and the optical axis of the liquid crystalline molecules 314b The directions of Ax2 are different (cross) from each other (FIG. 7 (B)). In the liquid crystal molecules 314b, for example, when an electric field is generated in the light modulation layer 314 due to a voltage difference between the electrodes, the optical axis Ax2 of the liquid crystal molecules 314b is other than 90 degrees with the surfaces of the transparent substrates 311 and 318. The structure is such that it crosses at an angle or becomes parallel. Therefore, when an electric field is generated in the light modulation layer 314 due to the voltage difference between the electrodes, the light modulation layer 314 has a large refractive index difference in all directions, and high scatterability can be obtained. Thus, for example, as shown in FIG. 7B, the light L1 traveling in the front direction and the light L2 and light L3 traveling in the oblique direction are scattered in the light modulation layer 314.

  The ordinary light refractive index of the liquid crystalline monomer 314a and the liquid crystalline molecule 314b may be somewhat shifted due to, for example, a manufacturing error, and for example, preferably 0.1 or less, preferably 0.05 or less. More preferable. In addition, the extraordinary light refractive index of the liquid crystalline monomer 314a and the liquid crystalline molecule 314b may also be somewhat shifted due to, for example, a manufacturing error, and for example, preferably 0.1 or less and 0.05 or less. Is more preferred.

In addition, the refractive index difference (Δn ₀ = extraordinary light refractive index n ₀ -ordinary light refractive index n ₁ ) of the liquid crystalline monomer 314 a and the refractive index difference of the liquid crystalline molecules 314 _b (Δn ₁ = abnormal light refractive index n ₂ − ordinary light refraction The ratio n ₃ ) is preferably as large as possible, preferably 0.05 or more, more preferably 0.1 or more, and still more preferably 0.15 or more. When the difference in refractive index between the liquid crystalline monomer 314a and the liquid crystalline molecule 314b is large, the scattering ability of the light modulation layer 314 becomes high, and the light guiding condition of the light guide 310 can be easily broken. It is easier to extract light from 310.

  The liquid crystalline monomer 314a contained in such a light modulation layer 314 has, for example, a linear structure or a porous structure which does not respond to an electric field, or a response speed slower than the response speed of the liquid crystal molecule 314b. It has a rod-like structure having The liquid crystalline monomer 314a may be, for example, an alignment and polymerizable material (for example, a monomer) aligned along the alignment direction of the liquid crystal molecules 314b or the alignment direction of the alignment films 313 and 316 by at least one of heat and light. It is formed by polymerization. On the other hand, the liquid crystal molecules 314b mainly include, for example, a liquid crystal material, and have a response speed sufficiently faster than the response speed of the liquid crystal monomer 314a.

  As a monomer having orientation and polymerization properties, any material having optical anisotropy and being composite with a liquid crystal may be used, and in particular, low molecular weight monomers curable by ultraviolet light are preferable. Since it is preferable that the direction of optical anisotropy of the liquid crystal and that after polymerizing low molecular weight monomers (polymer material) coincide with each other in the absence of an electric field, it is preferable before curing with ultraviolet light. Preferably, the liquid crystal and the low molecular weight monomer are aligned in the same direction. When a liquid crystal is used as the liquid crystal molecules 314 b and the liquid crystal is a rod-like molecule, it is preferable that the shape of the monomer material to be used is also rod-like. From the above, it is preferable to use a material having both polymerizability and liquid crystallinity as the monomer material. For example, as a polymerizable functional group, it is composed of an acryloyloxy group, a methacryloyloxy group, a vinyl ether group and an epoxy group It is preferred to have at least one functional group selected from the group. These functional groups can be polymerized by irradiation with ultraviolet light, infrared light or electron beam, or by heating. A liquid crystalline material having a multifunctional group can also be added in order to suppress the decrease in the degree of alignment upon irradiation with ultraviolet light. When the alignment films 313 and 316 are not used, a state in which these materials are aligned is temporarily created by an external field such as a magnetic field or an electric field, and the monomer is cured by ultraviolet light or heat to create an alignment state. It can also be done.

Incidentally, the type of transition by an electric field from transparently state to a scattering state (here to "the normally transparent") showed the type of transition from the scattering state to transparently state by an electric field (in this case, "a normally scattering" May be The light guide 310 may have a function of causing the light emitted from the sidelight light source 302 to be entirely or partially incident from the inside of the surface, and it is possible not only for transmission and scattering but also for optical phenomena such as diffraction and refraction. Can be used. However, in the case of considering the application of the display lighting device, a normally transparent type light guide is preferable from the viewpoint of efficiently guiding incident light far and emitting light from the light guide 310 efficiently. Hereinafter, description will be made using a normally transparent type light guide.

  Next, partial drive will be described. FIG. 8 is a view showing an example of partial driving of the planar light source device according to the second embodiment, and the planar light source device 300 is a planar light source such that light is emitted from the region (5) of the light guide 310. It is controlled by the device drive unit 500.

  The light modulation layer 320 corresponding to the area (6) of the light guide 310 is in a state where no voltage difference is generated between the electrodes corresponding to the area (6) (voltage no application state), as shown in FIG. Is a transparent state corresponding to

  The light modulation layer 321 corresponding to the area (5) of the light guide 310 is in a state (voltage applied state) in which a voltage difference is generated between the electrodes corresponding to the area (5), as shown in FIG. It is a corresponding scattering state.

  The light L4 emitted from the side light source 302 is incident from the side surface of the light guide 310, repeats total reflection between the transparent substrate 311 and the transparent substrate 318, and travels in the horizontal direction of FIG. ).

  Since the light modulation layer 320 is in the state of no voltage application, the directions of the optical axes of the liquid crystal monomer 314a and the liquid crystal molecule 314b coincide with each other, and there is almost no difference in refractive index. Accordingly, the light L4 incident on the area (6) corresponding to the light modulation layer 320 is transmitted without being scattered and travels in the horizontal direction (the area (5) side). That is, no light is emitted from the exit surface of the region (6) including the light modulation layer 320 controlled to the voltage non-application state.

  Since the light modulation layer 321 is in a voltage application state, the directions of the optical axes of the liquid crystal monomer 314a and the liquid crystal molecule 314b are different, and the difference in refractive index is large in all directions. Accordingly, the light L4 incident on the area (5) corresponding to the light modulation layer 321 is scattered. Then, a part of light scattered toward the image display panel 200 among the scattered light L4 is emitted from the light guide 310. As a result, light is emitted from the area (5) including the light modulation layer 321 controlled to the voltage application state to the image display panel 200. In the scattered light L4, part of the light traveling toward the reflective sheet 330 is emitted from the light guide 310, reflected by the reflective sheet 330, returned to the inside of the light guide 310, and the image display of the light guide 310 It emits from the panel 200 side. Therefore, by disposing the reflection sheet 330, the luminance emitted from the light exit surface of the light guide 310 can be enhanced.

  As described above, the planar light source device driving unit 500 generates an electric field in the light modulation layer by the voltage difference between the electrodes corresponding to the respective regions, thereby scattering light in the light modulation layers corresponding to the respective regions and guiding light. Light can be emitted from any area of the exit surface of the body 310.

  Next, a functional configuration example of the display device 100 including such a configuration will be described with reference to FIG. FIG. 9 is a diagram showing an example of a functional configuration included in the display device of the second embodiment.

  The display device 100 includes an image output unit 110, a signal processing unit 120, an image display panel 200, a planar light source device 300, an image display panel driving unit 400, and a planar light source device driving unit 500.

  The image output unit 110 outputs an image signal to the signal processing unit 120. In the image signal, color information (information of an image displayed on the display unit) corresponding to each pixel 201 of the image display panel 200 is set.

  The signal processing unit 120 is connected to an image display panel drive unit 400 that drives the image display panel 200 and a planar light source device drive unit 500 that drives the planar light source device 300. The signal processing unit 120 generates a display signal to be displayed on the image display panel 200 based on the image signal, and outputs the display signal to the image display panel drive unit 400. Further, the signal processing unit 120 generates a light source control signal for driving the planar light source device 300 based on the image signal, and outputs the light source control signal to the planar light source device driving unit 500.

  The image display panel 200 displays a divided area obtained by dividing the display surface as a display unit. This display unit is referred to as a pixel 201. For example, P × Q pixels 201 are arranged in a matrix to form a display surface.

  The pixel 201 is composed of three sub-pixels of red (R), green (G) and blue (B). Note that red (R), green (G), and blue (B) are an example, and for example, four subpixels to which white is added may constitute one pixel, or cyan, magenta, yellow, etc. It may be composed of

  The image display panel drive unit 400 includes a signal output circuit 410 and a scanning circuit 420, and drives the image display panel 200. The image display panel drive unit 400 selects a pixel 201 by sequentially outputting a scanning signal based on a display signal from the scanning circuit 420, and sequentially outputs a video signal based on the display signal from the signal output circuit 410. The operation (light transmittance) of the pixel 201 is controlled. In the present embodiment, the scanning circuit performs video scanning (display scanning) with the scanning signal sequentially from the lower side to the upper side of FIG.

  The planar light source device 300 is disposed on the back of the image display panel 200, and emits light toward the image display panel 200. In the planar light source device 300, the scanning direction of the scanning circuit of the image display panel 200 (the direction from the lower side to the upper side in FIG. 9) and the traveling direction of light of the sidelight light source 302 are parallel and opposite to each other. Be placed. That is, the planar light source device 300 sequentially scans the image by the video signal from the part (pixel 201) corresponding to the area (1) of the light guide 310 to the part (pixel 201) corresponding to the area (6). Are arranged with respect to the image display panel 200 so that

  The planar light source device drive unit 500 includes a light source drive circuit 510 and a light modulation drive circuit 520. The light source drive circuit 510 controls the output of light emitted from the side light source 302 of the planar light source device 300 based on the light source control signal output from the signal processing unit 120. The light modulation drive circuit 520 controls voltages of the upper electrode 312 and the lower electrode 317 based on the light source control signal output from the signal processing unit 120 to generate an electric field to be generated in the light modulation layer 314 corresponding to each region. Control. By this, the planar light source device driving unit 500 controls the luminance of light on the exit surface of the planar light source device 300 (the light guide 310).

  The processing operation of the signal processing unit 120 is realized by the display driver IC 100b or the CPU 100a1 shown in FIG. In the case of realization by the display driver IC 100b, an input signal is input to the display driver IC 100b via the CPU 100a1. The display driver IC 100 b generates a display signal and controls the image display panel 200. The light source control signal is generated and output to the LED driver IC 100c via the bus 100f.

  When realized by the CPU 100a1, a display signal is input from the CPU 100a1 to the display driver IC 100b. A light source control signal is also generated by the CPU 100a1 and output to the LED driver IC 100c via the bus 100f.

  Next, a functional configuration example further included in the signal processing unit 120 of the display device 100 will be described using FIG. FIG. 10 is a diagram showing an example of a functional configuration of a signal processing unit included in the display device of the second embodiment.

  The signal processing unit 120 includes an image analysis unit 121, a light source data storage unit 122, a drive pattern determination unit 123, an image processing unit 124, and a timing generation unit 125. An image signal is input to the signal processing unit 120 from the image output unit 110.

  The image analysis unit 121 analyzes the image signal, and the required luminance value of the light emitted from each area of the planar light source device 300 based on the image displayed on the image display panel 200 (hereinafter, the required luminance value for each area Calculate). The required luminance value is a luminance value for which the light to be emitted is required, and the planar light source device 300 is controlled to satisfy the required luminance value.

  The image analysis unit 121 analyzes the image signal of one image display frame before, and calculates the required luminance value of each region of the light guide 310 in the one image display frame from the image of one image display frame before. For example, the image analysis unit 121 analyzes the image signal one frame before the image display frame to calculate the required luminance value of the entire emission surface. The required luminance value of the entire emission surface may be a preset fixed value. Further, the image analysis unit 121 analyzes an image signal corresponding to each area in front of an image display frame (a signal necessary to determine an image to be displayed in a portion corresponding to each area in the image display panel 200). The required luminance value for each area may be calculated.

  Alternatively, every time an image signal corresponding to each area of one image display frame is input, the image analysis unit 121 analyzes the image signal corresponding to each input area, and the required luminance value of the light of each area is input. Calculate Note that the image analysis unit 121 may calculate the required luminance value for each block of the two-dimensional array in which each area is divided in parallel with the traveling direction of light, or may calculate the required luminance value for each pixel 201. Good.

  The light source data storage unit 122 stores luminance distribution information. When all the light sources 303a to 303j are turned on with a predetermined lighting amount and an electric field of a predetermined strength is generated for a predetermined time in the light modulation layer 314 corresponding to each area in a predetermined time, the luminance distribution information It is a luminance value of light emitted toward the image display panel 200. The light source data storage unit 122 stores luminance distribution information (light source lookup table) in which the luminance values of light are set in a table format.

  The light source look-up table is information unique to the display device 100, so it is created in advance and stored in the light source data storage unit 122. The light source data storage unit 122 is a region of m × n (1 ≦ m ≦ P, any integer satisfying 1 ≦ n ≦ Q) on the display surface of the image display panel 200 (the exit surface of the planar light source device 300). The luminance value of the planar light source device 300 detected for each area may be stored as luminance distribution information.

  The drive pattern determination unit 123 determines the lighting pattern of the side light source 302 and the voltage application pattern to the upper electrode 312 and the lower electrode 317 based on the required luminance value of each region and the light source lookup table (the drive pattern of the planar light source device 300 To determine).

  Note that an example of a drive pattern including such lighting patterns for the light sources 303a to 303j and application patterns for the upper electrode 312 and the lower electrode 317 of the light guide 310 will be described later.

The image processing unit 124 generates a display signal based on the image signal.
The timing generation unit 125 generates a timing signal for controlling the timing of controlling the light modulation layer 314 corresponding to each area of the planar light source device 300 by the planar light source device driving unit 500 to a scattering state (hereinafter, emission scan). . The timing generation unit 125 generates a timing signal according to the output timing of the display signal of the image processing unit 124.

  Next, the drive pattern of the present embodiment will be described with reference to FIG. FIG. 11 is a diagram showing a drive pattern of the planar light source device of the second embodiment. Note that FIG. 11 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire emission surface.

  In the graph of the LED current shown in FIG. 11, the horizontal axis represents time, and the vertical axis represents the value of the current supplied to the light sources 303a to 303j. Note that, in FIG. 11, a constant LED current i is supplied to the light sources 303a to 303j regardless of time, and the sidelight light source 302 enters light having a brightness corresponding to the LED current i into the light guide 310.

Further, the alternate long and short dash line shown in FIG. 11 indicates the scanning timing of the image scanning. In Figure 11, image scanning, when d ₁ has elapsed from the start pixel corresponding to the region (1) of the image display panel 200 (hereinafter, the pixel (1)) terminates for all. Further, image scanning of the image display panel 200, when d ₂ elapses pixels corresponding to the region (2) of the image display panel 200 (hereinafter, the pixel (2)) is completed for all. Similarly the image scanning of the image display panel 200, d ₃ to d ₆ elapses when region (3) of the image display panel 200 pixels corresponding to the ~ region (6) (hereinafter, the pixel (3) to (6)) All End for

Then, 1 image scanning of the image display panel 200 of the image display frame is terminated after the lapse d ₆ from the start. Thereafter, after the V blank period, video scanning of the next one image display frame is started.

Further, each of t ₁ to t ₆ shown in FIG. 11 is assigned as a time for the planar light source device 300 to control the light modulation layer 314 corresponding to each region to be in the scattering state and to emit light from each region. The scatter control time of the region is shown.

The total length of the scattering control times t _{1 to} t ₆ is the same as that of one image display frame. In FIG. 11, the length of each of the scattering control times t _{1 to} t ₆ is set to a length obtained by equally dividing the length of one image display frame into six in accordance with the number of regions. In addition, the scattering control time t _{1 to} t ₆ of each area is set so that the emission scanning of the area is not performed at the timing when the image scanning is performed on each area (the time of emitting light from each area It is set so that the image scanning for all the pixels corresponding to the area is completed).

The scattering control time t _{1 to} t ₆ starts after d ₁ (after the end of the image scanning in area (1)) has elapsed from the start of the image scanning and ends after d _{1 has} elapsed from the start of the image scanning of the next image display frame. ing. That is, the emission scan in FIG. 11 is performed with a delay of d ₁ than image scanning.

  According to the timing of such image scanning and emission scanning, the display apparatus 100 can surely perform the emission scanning of each area after the image scanning of the pixel 201 corresponding to each area of the image display panel 200 is completed. Therefore, according to the timing, the display device 100 can prevent the planar light source device 300 from emitting light to the pixel 201 while the pixel 201 of the image display panel 200 is being scanned. Thereby, the display device 100 can suppress moving image blurring.

  Furthermore, according to the above timing, the drive pattern determination unit 123 causes the image analysis unit 121 to input the image signal corresponding to each of the input regions every time the image signal corresponding to each region of one image display frame is input. It is also possible to determine the drive pattern using the required luminance value of light of each region calculated by analysis. Since the image signals are sequentially input, at the start of image scanning of one image display frame, an image of a portion corresponding to each area of the image display panel 200 in the one image display frame is not determined. Therefore, at the start of the image scanning of one image display frame, the image analysis unit 121 can not calculate the required luminance value of each region by analyzing the image signal corresponding to each region of the one image display frame. However, the emission scanning of each area in one image display frame is performed after the video scanning of the pixels 201 corresponding to each area in the one image display frame is completed, and the image analysis unit 121 outputs the emission scan of each area. The image signal corresponding to each area is input before.

  Therefore, the image analysis unit 121 can analyze the image signal corresponding to each area of the one image display frame and calculate the required luminance value of each area before emission scanning of each area in the one image display frame. . Thereby, the drive pattern determination unit 123 acquires the required luminance value of each area calculated by analyzing the image of the portion corresponding to each area by the image analysis unit 121 before emission scanning, and the planar light source device 300 The drive pattern of each area of can be determined.

  That is, the drive pattern determination unit 123 uses the required luminance value of each area suitable for the image to be displayed in the one image display frame, rather than the required luminance value of each area calculated by the image signal one image display frame earlier. Thus, the drive pattern of each area of the planar light source device 300 can be determined. Thereby, the display device 100 can improve the image quality.

Further, the scattering control time t ₁ in the surface light source device 300 shown in FIG. 11, between the areas t _1a to the light modulating layer 314 corresponding to _{(1) (t 1 = t} 1a), corresponding to the voltage difference v An electric field is generated to control the scattering state, and light corresponding to the LED current i is incident on the light guide 310.

Further, the scattering control time t ₂ in the surface light source device 300, the region between t _2a to the light modulating layer 314 corresponding to _{(2) (> t 1a)} , the scattering state by generating an electric field corresponding to the voltage difference v And light corresponding to the LED current i is incident on the light guide 310. Similarly, the scatter control time t ₃ ~t _6, the surface light source device 300, a region (3) to the t _3a to the light modulating layer 314 corresponding to _{(6) ~t 6a (> t} 2a ~t 5a) An electric field corresponding to the voltage difference v is generated to control the scattering state, and light corresponding to the LED current i is incident on the light guide 310.

  Generally, light incident on the side surface of the light guide 310 attenuates (decreases) in luminance as it travels in the light guide 310 (away from the incident side). Therefore, if all the regions are controlled in the same control mode, light of uniform luminance can not be emitted from the entire exit surface of the planar light source device 300. That is, in order to emit light of desired brightness from each area, it is desirable to control by control correspondence that includes the attenuation of light (reduction of the brightness) due to the distance of each area.

  Therefore, in FIG. 11, the display device 100 is driven based on the required luminance value and the light source look-up table, in which the light attenuation due to distance is corrected by the length of time for controlling the light modulation layer 314 in the scattering state. The planar light source device 300 is driven in a pattern.

  That is, the display device 100 drives the planar light source device 300 with a drive pattern in which the value of the LED current and the strength of the electric field are fixed in the entire region and only the length of time for generating the electric field is changed. .

  As described above, the display device 100 attenuates the light according to the distance by correcting the length of time for controlling the light modulation layer 314 to the scattering state according to the distance to the sidelight light source 302 in each region. , And can be corrected by the length of time for controlling the light modulation layer 314 in the scattering state.

  As a result, the display device 100 prevents the brightness of the light emitted from each area from deviating from the required brightness due to the attenuation of the light due to the distance, and the image display panel 200 is desired from each area of the light emission surface. It can emit light of luminance of

  The planar light source device 300 supplies different LED current to each of the light sources 303a to 303j, and emits light by controlling the luminance for each block of a two-dimensional array obtained by dividing each region in parallel with the traveling direction of the light. The case is equally applicable.

Note that, in the configuration in which the LED current of the sidelight light source 302 shown in FIG. 11 is constant and the scattering control times t _{1 to} t ₆ are equally allocated, light of uniform maximum luminance is transmitted to the image display panel 10 from the entire emission surface. When the light is emitted, its luminance is determined in the area (1) farthest from the sidelight light source 302. That is, the luminance obtained when the light modulation layer 314 corresponding to the region (1) is in the scattering state for the scattering control time t ₁ is a reference. Region (2)... The region (6) and the brightness of light incident on the region increases as it approaches the side light source 302, so that the time during which the light modulation layer 314 can be in the scattering state within the scattering control time (control time ) Becomes short ( _t1a > _t2a > _t3a > _t4a > _t5a > _t6a ). That is, in the remaining time excluding (subtracting) t _1a to t _6a in the scattering control time t _{1 to} t ₆ , the light modulation layer 314 corresponding to each region is always used regardless of the luminance of the emitted light. Is not controlled to the scattering state (no light is emitted from the exit surface).

Third Embodiment
Next, a third embodiment will be described. The same components as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the second embodiment shown in FIG. 11, in order to make the intensity (maximum intensity) of light that can be emitted from the planar light source device 300 uniform over the entire surface, the luminance is adjusted according to the luminance in the region (1) farthest from the sidelight light source 302. In a region near the sidelight light source 302, an idle time during which the light modulation layer 314 is not in a scattering state is provided. In the third embodiment, as in the second embodiment, in the configuration in which the scattering control time is set equally, the aspect of further improving the overall luminance is shown.

  A specific drive pattern will be described with reference to FIG. FIG. 12 is a diagram showing a drive pattern of the planar light source device of the third embodiment. FIG. 12 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire emission surface. In particular, differences from FIG. 11 will be mainly described.

In FIG. 12, the planar light source device 300 has idle time (t _2b , t _3b , t _4b) not controlling the light modulation layer 314 in the scattering state in the scattering control time (t _{2 to} t ₆ ) of each region. , T _{5 b} and t _{6 b} ), the light sources 303 a to 303 j are turned off (the LED current is turned to 0). Then, the planar light source device 300 controls the light modulation layer 314 in the scattering state during the control time (t _1a , t _2a , t _3a , t _4a , t _5a , t _6a ), and supplies the LED current _{i 0} greater the light source 303 a to 303 j.

  The idle time referred to here is a time which does not always contribute to the luminance of the light emitted when the surface light source device 300 emits light. The idle time is the remaining time obtained by subtracting the control time (the time for controlling the light modulation layer 314 into the scattering state when emitting the maximum luminance) from the scattering control time, and emitting in the region near the sidelight source 302 It is always provided regardless of the brightness of light.

By the way, in general, in the planar light source device 300, as the LED current supplied to the light sources 303a to 303j increases, the luminance of light entering the light guide 310 from the sidelight light source 302 becomes higher, and the light from the emission surface becomes higher. It will be possible to emit bright light. However, simply by changing the LED current supplied to the light source 303 a to 303 j from i to i ₀ (> i) in FIG. 11, it may exceed the allowable loss of the light source 303 a to 303 j.

  Therefore, in FIG. 12, the display device 100 stops the supply of the LED current to the light sources 303a to 303j in the idle time, and supplies the LED current to the light sources 303a to 303j only in the control time to exceed the allowable loss. The value of LED current that can be supplied is increased.

  According to such a drive pattern, the display device 100 can raise the upper limit of the luminance of light that can be emitted from the planar light source device 300. According to this, the display device 100 corrects the attenuation of the light due to the distance from the sidelight light source 302 in each region by the length of time for controlling the light modulation layer 314 to the scattering state, and the light with higher brightness Can be emitted from the planar light source device 300. As a result, the display device 100 can suppress the deterioration of the image quality.

  Note that when light emitted from a certain area is controlled to other than the maximum luminance, the light modulation layer 314 may not be controlled to be in a scattering state for part of the control time of the area. In this case, the display device 100 may stop the supply of the LED current also at the time.

Fourth Embodiment
Next, a fourth embodiment will be described. The same components as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the third embodiment, the display device 100 stops the supply of the LED current in the idle time, and supplies the LED current only in the control time, thereby increasing the value of the LED current that can be supplied without exceeding the allowable loss. And made it possible to emit high-intensity light.

  In the fourth embodiment, the display device 100 further improves the overall brightness by assigning the idle time to each area as an additional control time (hereinafter, an additional control time) with reference to the light source lookup table. Shows an aspect of

  A specific drive pattern will be described with reference to FIG. FIG. 13 is a diagram showing a drive pattern of the planar light source device of the fourth embodiment. FIG. 13 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire surface of the light emission surface. In particular, differences from FIG. 11 will be mainly described.

and t _2b, and t _3b, and a portion of t _4b are allocated as an additional control time in the area (1). Further, a part of t _{4 b and} a part of t _{5 b} are allocated to the area (2) as an additional control time. In addition, a part of _{t5b and} a part of _t6b are allocated to the area (3) as an additional control time. In addition, a part of t _{6 b} is allocated to the area (4) as an additional control time. Further, a part of t _{6 b} is allocated to the area (5) as an additional control time. Further, a part of t _{6 b} is allocated to the area (6) as an additional control time.

Then, the planar light source device 300 controls the light modulation layer 314 corresponding to the region (1) in the scattering state between t _{1 a} , t 2 _b , t _{3 b,} and a part of t _{4 b} . Further, the surface light source device 300, and t _2a, a part of t _4b, between a portion of the t _5b, and controls the light modulating layer 314 corresponding to the region (2) the scattering state. Further, the planar light source device 300 controls the light modulation layer 314 corresponding to the region (3) in a scattering state between t _{3 a} , a part of t _{5 b} , and a part of t _{6 b} . Further, the planar light source device 300 controls the light modulation layer 314 corresponding to the region (4) to be in a scattering state between t _{4 a} and a part of t _{6 b} . In addition, the planar light source device 300 controls the light modulation layer 314 corresponding to the region (5) in the scattering state between t _{5 a} and a part of t _{6 b} . In addition, the planar light source device 300 controls the light modulation layer 314 corresponding to the region (6) in a scattering state between t _6a and a part of t _6b .

  The additional control time is assigned such that the maximum luminance of light that can be emitted from each area is uniform (the luminance of light that can be improved by the additional control time is uniform in each area). The display device 100 refers to the light source look-up table and corrects the light attenuation by distance according to the length of time to assign the light so that the luminance improved by each area by the additional control time becomes the same in each area. Assigned

  According to such a drive pattern, the display device 100 can raise the upper limit of the luminance of light that can be emitted from the planar light source device 300 by the additional control time. Therefore, the display device 100 planarizes the light with higher brightness while correcting the attenuation of the light due to the distance from the side light source 302 in each region by the length of time for controlling the light modulation layer 314 to the scattering state. The light can be emitted from the light source device 300. As a result, the display device 100 can suppress the deterioration of the image quality.

  In addition, the display device 100 allocates the idle time of each area to the area far from the sidelight light source 302 as the additional control time. That is, the additional control time is assigned to the area (the area in which the video scanning has been completed) in which the control time has already ended. Thus, the display device 100 can prevent the planar light source device 300 from emitting light to the pixel 201 while the pixel 201 of the image display panel 200 is being scanned.

Fifth Embodiment
A fifth embodiment will now be described. The same components as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the fourth embodiment, the display device 100 does not contribute to the luminance of the emitted light by driving the planar light source device 300 with the drive pattern in which the idle time of each area is allocated to each area as the additional control time. It eliminated time and made it possible to emit high-intensity light. In the fifth embodiment, by using the light (leakage light) which has not been emitted from the light guide 310 while controlling the light modulation layer 314 corresponding to each region to the scattering state, the whole can be further improved. The aspect which improves a brightness | luminance is shown.

  A specific drive pattern will be described with reference to FIG. FIG. 14 is a diagram showing a drive pattern of the planar light source device of the fifth embodiment. FIG. 14 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire emission surface. In particular, differences from FIG. 13 will be mainly described.

In Figure 14, the surface light source device 300, during the control time t _2a, together with the light modulating layer 314 corresponding to the region (2), corresponds to the far region (1) from the sidelight source 302 than the region (2) The light modulation layer 314 is controlled to be in the scattering state. Further, the surface light source device 300, the control during the time t _3a, together with the light modulating layer 314 corresponding to the region (3), an optical modulation corresponding to an area far (2) from the sidelight source 302 than the region (3) The layer 314 is controlled to the scattering state. Further, the planar light source device 300 performs light modulation corresponding to the area (3) farther from the side light source 302 than the area (4) together with the light modulation layer 314 corresponding to the area (4) during the control time t _4a. The layer 314 is controlled to the scattering state. Further, the planar light source device 300 performs light modulation corresponding to the area (4) farther from the side light source 302 than the area (5) together with the light modulation layer 314 corresponding to the area (5) during the control time _t5a. The layer 314 is controlled to the scattering state. Further, the planar light source device 300 performs light modulation corresponding to the area (5) farther from the side light source 302 than the area (6) together with the light modulation layer 314 corresponding to the area (6) during the control time t _6a. The layer 314 is controlled to the scattering state.

  In general, when the light modulation layer 314 corresponding to the area is controlled to be in the scattering state, the light guided inside the light guide 310 to the area is emitted from the area. However, a part of the light of the light guided inside the light guide 310 to the area is not emitted from the light guide 310, but to the next area (the adjacent area controlled to the scattering state). It may progress.

  Therefore, in FIG. 14, the planar light source device 300 simultaneously controls the light modulation layer 314 in a region (next region) farther from the sidelight light source 302 than the corresponding region at the control time of each region. The light which has not been emitted during the control time of each region (leakage light) is emitted.

  According to such a drive pattern, the display device 100 emits light from the planar light source device 300 by the use of light (leakage light) that has not been emitted from the light guide 310 during the control time of each region. The upper limit of possible light brightness can be raised.

  Note that when light emitted from a certain area is controlled to other than the maximum luminance, the light modulation layer 314 may not be controlled to be in a scattering state for part of the control time of the area. In this case, the leaked light can not be used in the time. However, at this time, the light travels to the next area without being emitted, so that the area farther from the side light source 302 than the area in the control time uses more light than the leaked light it can. That is, the display device 100 can reliably anticipate an improvement in luminance by using the leaked light. Therefore, according to such a drive pattern, the display device 100 can raise the upper limit of the luminance of light that can be emitted from the planar light source device 300 by the amount of using the leaked light.

  According to this, the display device 100 corrects the attenuation of the light due to the distance from the sidelight light source 302 in each region by the length of time for controlling the light modulation layer 314 to the scattering state, and the light with higher brightness Can be emitted from the planar light source device 300. As a result, the display device 100 can suppress the deterioration of the image quality.

  Since the luminance of leaked light is information unique to the display device 100 (according to the material etc.), the luminance distribution information (leakage light look-up table) in which the luminance value of leaked light is set in a table format in advance Are stored in the light source data storage unit 122.

  Then, the drive pattern determination unit 123 determines the drive pattern of the planar light source device 300 with reference to the required luminance value of each area, the light source look-up table, and the leaked light look-up table. When there is a time during which the light modulation layer 314 is not controlled to the scattering state (a time when the leaked light can not be used) in part of the control time, the drive pattern determination unit 123 performs the leaked light lookup for the time Instead of the table, the light source lookup table may be referred to.

  As shown in FIG. 14, leaked light can not be used in the area (6) closest to the sidelight light source 302. Therefore, the display device 100 refers to the luminance look-up table and the leaked light look-up table, and corrects the improvement of the luminance by the other area using the leaked light by the additional control time or control time of the area (6) Do. For example, the display apparatus 100 extends the length of the additional control time allocated to the area (6) by the upper limit of the luminance of the light that can be emitted, which improves when another area uses leaked light.

  As described above, the display device 100 corrects, for the area (6), the portion where leakage light can not be used by the additional control time or the control time of the area (6), to obtain the maximum luminance of light that can be emitted from each area. Can be made uniform.

  Note that, in FIG. 14, the display device 100 uses only the leaked light in the control time, but the present invention is not limited to this. For example, the display device 100 can similarly use leaked light in the additional control time.

  In addition, leaked light can be similarly used even when the additional control time is not allocated (in the case of FIG. 11). In this case, if the control time of the area (6) is extended by the upper limit of the luminance of the light that can be emitted, which is improved when the other areas utilize leaked light, the light which can be emitted from each area Maximum brightness can be kept uniform.

[Modification]
Next, a modification of FIG. 14 will be described with reference to FIG. FIG. 15 is a view showing a modification of the drive pattern of the fifth embodiment. FIG. 15 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire emission surface. In particular, differences from FIG. 14 will be mainly described.

In FIG. 15, the planar light source device 300 controls the light modulation layer 314 corresponding to each area to the scattering state also for the time between the additional control time and the additional control time. Specifically, the planar light source device 300 continuously forms the light modulation layer 314 corresponding to the region (1) in t 2 _b , t _{3 a} , t _{3 b} , t _{4 a,} and a part of t _{4 b.} It controls to the scattering state. Further, the surface light source device 300, a part of t _4b, and t _5a, and controls the light modulating layer 314 corresponding to the region (2) in succession in the scattering state in the part of t _5b. Further, the surface light source device 300, a part of t _5b, and t _6a, and controls the light modulating layer 314 corresponding to the region (3) in succession in the scattering state in the part of t _6b.

  The time between the additional control time and the additional control time corresponds to the control time of the other area, and at this time, the leaked light is already used. Therefore, even if the light modulation layer 314 corresponding to the region at the time is controlled to be in the scattering state, it can not be expected much from the viewpoint of improving the luminance. However, according to the drive pattern, the display device 100 also controls the time between the additional control time and the additional control time to the scattering state, so the scattering state and the non-scattering state of the light modulation layer 314 corresponding to each region The number of switching times can be reduced. That is, the display device 100 can facilitate control of the planar light source device 300.

Sixth Embodiment
A sixth embodiment will now be described. The same components as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the fourth embodiment, the planar light source device 300 controls the area into the scattering state in the control time of the area and the idle time of the other area assigned to the area as the additional control time. In the sixth embodiment, the display device 100 facilitates control by driving the planar light source device 300 with a drive pattern to which the scattering control time of the total length of the control time and the additional control time is allocated. .

  A specific drive pattern will be described with reference to FIG. FIG. 16 is a diagram showing a drive pattern of the planar light source device of the sixth embodiment. FIG. 16 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire emission surface. In particular, differences from FIG. 13 will be mainly described.

T _{1 to} T ₆ indicate the scattering control time. T ₁ is the control time _(part of _{t 2b} and _{t 3b} and _{t 4b) (t 1a)} and the additional control time and the total length of the area (1) shown in FIG. 13. T ₂ are a control time _{(t 2a)} and _(a part and a part of _{t 5b} of _{t 4b)} and the total length of the additional control time region (2) shown in FIG. 13. T ₃ is a control time _{(t 3a)} and _(part a part of _{t 6b} of _{t 5b)} and the total length of the additional control time region (3) shown in FIG. 13. T ₄ is a control time _(part of _{t 6b) (t 4a)} and the additional control time and the total length of the area (4) shown in FIG. 13. T ₅ is the control time _{(t 5a)} and _(part of _{t 6b)} additional control time and the total length of the region (5) shown in FIG. 13. T ₆ is the total length of the control time (t _6a ) of the region ( 6 ) shown in FIG. 13 and the additional control time (a part of t _{6 b} ). That is, each area is assigned a scattering control time according to the distance from each side light source 302 so that idle time does not occur within the scattering control time.

Then, the planar light source device 300 generates an electric field corresponding to the voltage difference v during T _{1 in} the light modulation layer 314 corresponding to the region (1) to control it in the scattering state, and corresponds to the LED current i. Light is incident on the light guide 310. In addition, the planar light source device 300 generates an electric field corresponding to the voltage difference v in the light modulation layer 314 corresponding to the region (2) during T ₂ to control it to the scattering state, and corresponds to the LED current i. Light is incident on the light guide 310. Similarly, the planar light source device 300 controls the light modulation layer 314 corresponding to the regions (3) to (6) to generate an electric field corresponding to the voltage difference v throughout T _{3 to} T ₆ to control the scattering state. Light corresponding to the LED current i is incident on the light guide 310.

  According to such a drive pattern, the display device 100 can reduce the number of times of switching between the scattering state and the non-scattering state of the light modulation layer 314 corresponding to each region. That is, the display device 100 can facilitate control of the planar light source device 300.

Seventh Embodiment
Next, a seventh embodiment will be described. The same components as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted. In the sixth embodiment, the display device 100 facilitates control by driving the planar light source device 300 with a drive pattern to which the scattering control time of the total length of the control time and the additional control time is allocated. In the seventh embodiment, by using light (leakage light) that has not been emitted from the light guide 310 while controlling the light modulation layer 314 corresponding to each region to the scattering state, the entire system can be further improved. The aspect which improves a brightness | luminance is shown.

  A specific drive pattern will be described with reference to FIG. FIG. 17 is a diagram showing a drive pattern of the planar light source device of the seventh embodiment. FIG. 17 shows a drive pattern in the case where the planar light source device 300 emits light of maximum luminance (white display) uniformly from the entire emission surface. In particular, differences from FIG. 16 will be mainly described.

In Figure 17, the surface light source device 300, between the scattering control time T _2, together with the light modulating layer 314 corresponding to the region (2), corresponding to the region (1) remote from the sidelight source 302 than the region (2) The light modulation layer 314 is controlled to be in the scattering state. Further, the surface light source device 300, between the scattering control time T _3, with the light modulation layer 314 corresponding to the region (3), away from the sidelight source 302 than the region (3) region (2), (1) Is controlled to be in the scattering state. Further, the surface light source device 300, between the scattering control time T _4, the regions with the light modulation layer 314 corresponding to (4), region (4) region further from the sidelight source 302 than (3) - (1) Is controlled to be in the scattering state. Further, the surface light source device 300, between the T _5a of the scattering control time T ₅ (while the image scanning is not performed), the light modulating layer 314 corresponding to the region (5), than the region (5) The light modulation layer 314 corresponding to the regions (4) to (1) far from the sidelight light source 302 is controlled to be in the scattering state. Further, the surface light source device 300, between the T _5b of the scattering control time T ₅ (while image scanning region (1) is being performed), the light modulating layer 314 corresponding to the region (5), region The light modulation layer 314 corresponding to the regions (4) and (2) farther from the sidelight light source 302 than in (5) is controlled to be in the scattering state. Further, the surface light source device 300, between the scattering control time T _6, the region with the light modulation layer 314 corresponding to (6), region area far from the sidelight source 302 than (6) (5) - (2) Is controlled to be in the scattering state.

  That is, by simultaneously controlling the light modulation layer 314 in a region which is far from the sidelight light source 302 and not subjected to the image operation at the scattering control time of each region, scattering in each region is simultaneously performed. It emits light that has not been emitted during the control time (leakage light).

  According to such a drive pattern, the display device 100 receives the light (leakage light) that has not been emitted from the light guide 310 during the scattering control time of each region from the planar light source device 300. The upper limit of the luminance of the light that can be emitted can be raised.

  Since the luminance of leaked light is information unique to the display device 100 (according to the material etc.), the luminance distribution information (leakage light look-up table) in which the luminance value of leaked light is set in a table format in advance Are stored in the light source data storage unit 122.

  Then, the drive pattern determination unit 123 determines the drive pattern of the planar light source device 300 with reference to the required luminance value of each area, the light source look-up table, and the leaked light look-up table. When there is a time during which the light modulation layer 314 is not controlled to be in the scattering state (a time during which the leaked light can not be used) in part of the scattering control time, the drive pattern determination unit 123 looks for leaked light for that time. Instead of the up table, the light source lookup table may be referred to.

  In addition, as shown in FIG. 17, the area (6) closest to the sidelight light source 302 can not utilize leaked light. Therefore, the display apparatus 100 refers to the luminance look-up table and the leaked light look-up table, and corrects the improvement of the luminance by using the leaked light in the other area with the scattering control time of the area (6). For example, the display apparatus 100 lengthens the length of the scattering control time allocated to the area (6) by the upper limit of the luminance of the light that can be emitted, which is improved when the other area uses leaked light.

  As described above, the display apparatus 100 uniformly compensates for the inability to use leaked light in the area (6) by the scattering control time of the area (6), thereby uniformly maximizing the maximum luminance of light that can be emitted from each area. can do.

  The light modulation layer 314 in each area is in the scattering state while the image scanning is not performed on the area among the scattering control time of the area and the scattering control time of the area closer to the sidelight source 302 than the area. Although explained as controlling, it does not restrict to this. For example, when leaked light is already used in other regions, even if the light modulation layer 314 is controlled to be in the scattering state, it can not be expected much from the viewpoint of improving the luminance. Therefore, the light modulation layer 314 of each area is scattered only during the scattering control time of the area and the time when the leaked light can be reliably used (the scattering control time of the adjacent area on the side light source 302 side of the area) It may be controlled to the state.

  The above processing functions can be realized by a computer. In that case, a program is provided which describes the processing content of the function that the display device should have. The above processing functions are realized on the computer by executing the program on the computer. The program in which the processing content is described can be recorded on a computer readable recording medium. Examples of the computer-readable recording medium include a magnetic storage device, an optical disc, a magneto-optical recording medium, a semiconductor memory, and the like. Examples of the magnetic storage device include a hard disk drive (HDD: Hard Disk Drive), a flexible disk (FD), a magnetic tape, and the like. The optical disc includes a DVD (Digital Versatile Disc), a DVD-RAM, a CD (Compact Disc) -ROM, a CD-R (Recordable) / RW (Rewritable), and the like. Magneto-optical recording media include MO (Magneto-Optical disk) and the like.

  In the case of distributing the program, for example, a portable recording medium such as a DVD, a CD-ROM or the like in which the program is recorded is sold. Alternatively, the program may be stored in the storage device of the server computer, and the program may be transferred from the server computer to another computer via a network.

  The computer executing the program stores, for example, the program recorded on the portable recording medium or the program transferred from the server computer in its own storage device. Then, the computer reads the program from its storage device and executes processing according to the program. The computer can also read the program directly from the portable recording medium and execute processing according to the program. Also, each time a program is transferred from a server computer connected via a network, the computer can sequentially execute processing in accordance with the received program.

  In addition, at least a part of the above processing functions can be realized by an electronic circuit such as a digital signal processor (DSP), an application specific integrated circuit (ASIC), or a programmable logic device (PLD).

  It is understood that those skilled in the art can conceive of various changes and modifications within the scope of the concept of the present technology, and such changes and modifications are also within the scope of the present technology. For example, a person skilled in the art may appropriately add, delete, or change design elements of the above-described embodiments, or add, omit, or change conditions of processes in the embodiments of the present technology. As long as it is included in the scope of the present technology.

  Further, it is understood that other effects and advantages provided by the aspects described in the present embodiment will be apparent from the description of the present specification, or those that can be appropriately conceived by those skilled in the art, as a matter of course provided by the present technology. Ru.

(1) One aspect of the disclosed invention is an image display panel in which display scanning is sequentially performed in a first direction;
A light source for emitting light, and the light is disposed on the back surface of the image display panel and is incident on the side surface of the surface facing the image display panel, and is directed to a second direction opposite to the first direction. A light modulation layer capable of guiding the light and being controllable to be in a transmitting state for transmitting the light or in a scattering state for scattering the light is disposed in a plurality of regions divided in a direction intersecting the second direction. A light source device comprising:
Each region emits light to the image display panel within the scattering control time of the light modulation layer corresponding to each region sequentially assigned to each region in the first direction so as not to overlap in time. A control device for controlling the light modulation layer corresponding to each region to a scattering state for a length of time according to the distance from the side surface of each region according to the intensity of the light;
A display device having

(2) In one aspect of the disclosed invention, the plurality of regions include a first region and a second region spaced apart from the side surface more than the first region,
The controller is
It corresponds to the first area or the second area at an idle time in which the light modulation layer corresponding to the first area in the scattering control time of the first area is not controlled to the scattering state The light modulation layer can be controlled to be in a scattering state to uniformly increase the upper limit of the intensity of the light that can be emitted from each region to the image display panel.
It is a display apparatus as described in (1).

(3) In one aspect of the disclosed invention, the plurality of regions include a first region and a second region spaced apart from the side surface more than the first region,
The controller is
The light modulation layer corresponding to the first region is controlled to be in a scattering state during the scattering control time of the first region, and the light modulation layer in the second region is also controlled to be in a scattering state.
It is a display apparatus as described in (1).

(4) One aspect of the disclosed invention relates to the image display panel from each area when the light modulation layer corresponding to each area is controlled to the scattering state during the scattering control time of each area. The intensity of the emitted light is uniform,
It is a display apparatus as described in (1).

(5) One embodiment of the disclosed invention is an image display panel;
A light source for emitting light, a light transmitting state which is disposed on a back surface of the image display panel, enters the light from a side surface of the surface facing the image display panel, and transmits the light or scatters the light A light source comprising: a plurality of light guides arranged in a plurality of regions divided in a direction intersecting the traveling direction of light;
Within the scattering control time of the light modulation layer corresponding to each area set so as not to overlap in time, according to the intensity of the light emitted from each area to the image display panel, The light modulation layer corresponding to each area is controlled to the scattering state by the length of time according to the distance from the side, and the light modulation layer corresponding to each area within the scattering control time allocated to each area A controller for stopping emission of the light from the light source at a time when the light source is not controlled to the scattering state;
A display device having

  Reference Signs List 1 display device 10 image display panel 20 light source device 21 light source 22 light guide 22a to 22f area 23 side surface 30 ・ ・ ・ Control device

Claims (4)

An image display panel in which display scanning is sequentially performed in a first direction;
A light source for emitting light, and the light is disposed on the back surface of the image display panel and is incident on the side surface of the surface facing the image display panel, and is directed to a second direction opposite to the first direction. A light modulation layer capable of guiding the light and being controllable to be in a transmitting state for transmitting the light or in a scattering state for scattering the light is disposed in a plurality of regions divided in a direction intersecting the second direction. A light source device comprising:
Each region emits light to the image display panel within the scattering control time of the light modulation layer corresponding to each region sequentially assigned to each region in the first direction so as not to overlap in time. A controller for controlling the light modulation layer corresponding to each region to a scattering state for a length of time according to the distance from the side surface of each region according to the intensity of the light ;
The plurality of regions include a first region and a second region closer to the side surface than the first region,
The controller is
The light modulation layer corresponding to the first area is scattered at idle time when the light modulation layer corresponding to the second area within the scattering control time of the second area is not controlled to the scattering state The upper limit of the intensity of the light that can be emitted to the image display panel from each region can be uniformly increased by making the state controllable.
Viewing equipment. Before Symbol control device,
Controls the light modulation layer corresponding to the second region in the scatter control time of the second region in the scattering state, also controls the scattering state the light modulating layer of the first region,
The display device according to claim 1. The intensity of the light emitted from each area to the image display panel is uniform when the light modulation layer corresponding to each area is controlled to the scattering state during the scattering control time of each area.
The display device according to claim 1. An image display panel,
A light source for emitting light, a light transmitting state which is disposed on a back surface of the image display panel, enters the light from a side surface of the surface facing the image display panel, and transmits the light or scatters the light A light source comprising: a plurality of light guides arranged in a plurality of regions divided in a direction intersecting the traveling direction of light;
Within the scattering control time of the light modulation layer corresponding to each area set so as not to overlap in time, according to the intensity of the light emitted from each area to the image display panel, The light modulation layer corresponding to each area is controlled to the scattering state by the length of time according to the distance from the side, and the light modulation layer corresponding to each area within the scattering control time allocated to each area A controller for stopping emission of the light from the light source at a time when the light source is not controlled to the scattering state ;
The plurality of regions include a first region and a second region closer to the side surface than the first region,
The controller is
The light modulation layer corresponding to the first area is scattered at idle time when the light modulation layer corresponding to the second area within the scattering control time of the second area is not controlled to the scattering state The upper limit of the intensity of the light that can be emitted to the image display panel from each region can be uniformly increased by making the state controllable.
Viewing equipment.

Images