JP2010113160A - Video display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video display apparatus that displays a video in a prescribed direction and has high efficiency of use of light. <P>SOLUTION: The stereoscopic image display apparatus includes: a display panel 2; an image control section 4 for controlling the operation of the display panel 2; a back light section 7; and a light source control section 8. The back light section 7 illuminates the display panel 2. The back light section 7 includes a light source section 5 and a light distribution lens array 6. The light source section 5 is disposed on the incident face side of the light distribution lens array 6, and includes a plurality of light source elements. The light distribution lens array 6 has a plurality of apertures corresponding to a light source group. A light beam from the light source element passed through each aperture illuminates the display panel 2. The light source control section 8 controls the turning on of each light source element. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a video display device, and more particularly, to a video display device that performs light distribution control type illumination control that outputs light whose spatial distribution is controlled.

  In recent years, various video providing methods have been considered in the video display field. For example, a light distribution limited display device that can observe an image only from a specific direction and a stereoscopic image display device that allows a user to perceive a stereoscopic image are being put into practical use.

  Specific examples of the light distribution-restricted display device include a mobile phone and a mobile information device monitor with a narrow viewing angle. This monitor is characterized in that the display content of the monitor cannot be seen from an observation position from an angle other than the person viewing from near the front. Another specific example of the light distribution restriction type display device is a two-way monitor for car navigation. This two-way monitor is arranged near the center console and can display a map screen in the driving direction and a TV image in the passenger seat direction. For such a light distribution-restricted display device, for example, a dual-view liquid crystal or a bale-view liquid crystal described in Patent Document 1 (Japanese Patent No. 4074233) can be used.

  The stereoscopic image display device displays an image that can be perceived stereoscopically when a person views the image. It is said that there are convergence, binocular parallax, motion parallax, and adjustment as elements that are perceived stereoscopically when a human sees an object, and a stereoscopic video display device uses these elements.

  Convergence is a movement in which the left and right eyeballs face inward when looking at an object. When the brain recognizes the muscle tension that gives the eyes a vergence angle, humans get a three-dimensional effect. The binocular parallax is a deviation (so-called parallax) of an image on the retina projected onto both eyes when the gazing point is observed. Humans perceive this binocular parallax as a stereoscopic effect. Motion parallax is a change in the appearance of an object as the viewpoint moves when the viewpoint for viewing the object is changed. Humans perceive this motion parallax as a stereoscopic effect. Adjustment means that the thickness of the lens changes according to the distance of the object being viewed. When the brain recognizes muscle tension that changes the thickness of the lens, humans gain a three-dimensional effect.

  There are four types of conventional stereoscopic video devices that utilize the perceptual action that promotes stereoscopic vision: (i) binocular, (ii) multi-view, (iii) volume display, and (iv) aerial image reproduction. Can be divided roughly. The features of these systems are briefly described below.

  (I) The twin-lens system prepares an image when viewed with the left eye and an image when viewed with the right eye, and presents the left-eye image to the left eye of the user, This is a method for presenting a right-eye video. The binocular system gives a stereoscopic effect mainly using convergence and binocular parallax. There are several methods for independently presenting two types of video to both eyes.

  It is well known that glasses are prepared to separate the left and right images. Specifically, there is an anaglyph type that displays the image for the left eye in red and the image for the right eye in blue, and looks through the blue / red glasses. Alternatively, there is a method in which the left-eye video and the right-eye video are alternately displayed in time, and the left and right videos are independently presented to the user through glasses equipped with time-division shutters. Recently, there has been a method of displaying left and right eye images by changing the polarization direction, and independently presenting left and right images to a user using glasses equipped with polarizing filters for separating the left and right images. In this method, since the glasses can be made lighter than the method using the time-division shutter, the burden on the user can be reduced.

  Some independent presentation methods do not use glasses. As a method not using glasses, there is a method of separating a display image into left and right images using a parallax barrier or a lenticular lens. Patent Document 2 (Japanese Patent Laid-Open No. 2005-77472) discloses a liquid crystal display panel, first illumination light having a peak of emitted light intensity in the direction of one eye of the user, and the other of the user. A liquid crystal display device is disclosed that includes a surface light source that alternately emits second illumination light having a peak of emitted light intensity in the direction of the eyes. In this liquid crystal display device, left-eye image data and right-eye image data are alternately written on the liquid crystal display panel, and either the first illumination light or the second illumination light is synchronized with the writing of the image data. The light is emitted from the surface light source.

  (Ii) In the multi-view type, the viewpoint is prepared in addition to the two points of the binocular type. That is, the multi-view method is a method in which left-eye video and right-eye video from a plurality of viewpoints are presented independently with respect to the viewing direction using a parallax barrier or a lenticular lens. In the multi-view system, in addition to the convergence and binocular parallax, as the observation position moves, the left and right images are switched by the number of viewpoints and projected to the user, giving the user a stereoscopic effect due to motion parallax. Can do.

  Regarding multi-view video display, Patent Document 3 (Japanese Patent No. 3054312) detects a user's viewpoint position and reconstructs an image having the detected position as a viewpoint from previously prepared multi-view image data. An image processing apparatus is disclosed.

  Japanese Patent Laid-Open No. 2007-47563 discloses a display device that controls the light emission direction by determining the opening position of the shutter unit corresponding to the lens unit according to the position of the user. Has been.

  (Iii) The volume display type is to display an image at a position corresponding to the depth by, for example, preparing a plurality of display surfaces in the depth direction or rotating the display surface. In the volume display type, in addition to convergence and binocular parallax, it is possible to create a stereoscopic effect by adjustment.

  (Iv) The aerial image reproduction method is a method of reproducing the subject's light beam itself. The aerial image reproduction method is an excellent method in that the user can obtain any of the effects of convergence, binocular parallax, motion parallax, and adjustment, as in the case of actually viewing an object. This method includes a light beam reproduction method and holography.

  Here, the principle of stereoscopic image display by the light beam reproduction method will be briefly described with reference to FIGS. FIG. 1 is a side view of an optical system of a stereoscopic image display apparatus using a light source reproduction method. FIG. 2 is a perspective view of the optical system of the stereoscopic image display apparatus using the light source reproduction method.

  As shown in FIGS. 1 and 2, the stereoscopic video display device includes a display panel 12 and a lens array 13. The display panel 12 has a plurality of pixels. For example, a liquid crystal display is used as the display panel 12. The lens array 13 has a plurality of lenses arranged in one plane. Here, as shown in FIG. 2, an example in which a microlens array in which microlenses are two-dimensionally arranged is used as the lens array 13 will be described.

  The stereoscopic video display device displays an element image 14 generated by a plurality of pixels on the display panel 12. The light rays of the image of the display panel 12 obtained through the lens array 13 are as shown in FIG. 1. When the user observes the element image 14 displayed on the display panel 12 through the lens array 13, the reproduced image 11 is present. (In other words, the stereoscopic image display device displays the element image 14 as if the user who observed the element image 14 through the lens array 13 feels as if the reproduced image 11 exists.) Display on the display panel 12). For this reason, the convergence, binocular parallax, and adjustment are all given to the user in the same manner as when the object is naturally seen.

Further, as shown in FIG. 2, each point of the image reproduced by the light beam reproduction method emits a light beam in each direction through the lens. In FIG. 2, a light beam corresponding to the point A of the reproduced image 11 is shown. For this reason, when the observation direction is changed, the user observes an image viewed from that direction. That is, the user feels motion parallax. In the example described here, since the stereoscopic image display apparatus uses a microlens array as the lens array 13, it is possible to give the user motion parallax in the vertical and horizontal directions.
Japanese Patent No. 4074233 JP 2005-77472 A Japanese Patent No. 3054312 JP 2007-47563 A

  In the conventional light distribution restriction type display device such as the dual view liquid crystal or the bale view liquid crystal described in Non-Patent Document 1, although the direction in which light can be distributed can be limited, the direction in which light can be distributed is fixed, and the observation position of the user is fixed. A display image cannot be created following the change. Therefore, the inconvenience that the observation position of the user's image is limited has occurred.

  Also, in the stereoscopic display device, it is preferable that the display position of the stereoscopic image can be freely changed. For this purpose, the direction of light applied to the planar image display device (display panel 12 in FIGS. 1 and 2) can be freely set. Need to be able to control. However, the conventional stereoscopic display device cannot freely control the direction of light applied to the flat image display device. For example, the apparatus described in Patent Document 2 can emit irradiation light only in a predetermined direction. The same applies to the device described in Patent Document 3. Moreover, in the apparatus described in Patent Document 4, there is a problem that light for illuminating a portion that is not opened is not used, and light use efficiency as a display apparatus is very low.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an image display device that can display an image in a predetermined direction and has high light utilization efficiency.

  The present invention according to one aspect includes an image display unit having a plurality of pixels, a light source unit including a plurality of light source groups including a plurality of light source elements, a light source control unit capable of independently controlling each light source element, and an image display A light guide unit that is disposed between the light source unit and the light source unit, has a plurality of openings corresponding to the plurality of light source groups, and guides the transmitted light to illuminate the image display unit. The unit controls each light source element so that light emitted from each light source group passes through the opening and is guided in a predetermined direction.

Preferably, the light beam guided at each opening of the light guide is substantially parallel light.
Preferably, the light source control unit controls each light source element independently so as to guide light in a plurality of predetermined directions.

  Preferably, the light source device further includes a position detection unit that detects the position of the observer, and the light source control unit is capable of emitting a light beam traveling in the direction of the observer based on the position of the observer detected by the position detection unit. Lights up.

  Preferably, a pupil position detection unit that detects the position of the pupil of the observer is further provided, and the light source control unit can emit light that travels in the direction of the pupil based on the pupil position detected by the pupil position detection unit. Turn on the light source element.

More preferably, the light guide unit is a lens array having a plurality of lenses.
More preferably, each light source element is arranged at a substantially focal length of the lens array.

More preferably, the lens array is a lenticular lens.
More preferably, the lens array is a two-dimensional lens array in which a plurality of lenses are arranged on a lattice point of a planar grating.

More preferably, each light source element is a semiconductor light emitting element.
More preferably, each light source element is a semiconductor light emitting element, and the light source unit further includes a linear light guide plate arranged along the lens axis direction of the lenticular lens.

  More preferably, it further includes a light direction limiting unit that limits a traveling direction of light transmitted through each pixel.

  More preferably, the image display unit displays an image in accordance with a light reproduction type stereoscopic display method.

More preferably, the light direction limiting unit is a lenticular lens.
More preferably, the light direction limiting unit is a two-dimensional lens array in which a plurality of lenses are arranged on lattice points of a planar lattice.

  Preferably, the image display unit further includes an image control unit that controls the image display unit so as to divide and display a plurality of images in time, and the light source control unit turns on each light source element in synchronization with the display of the plurality of images. To control.

  According to the present invention, there are a plurality of openings corresponding to the light source groups, a light guide section that guides the light beams that have passed through the opening sections to illuminate the image display section, and light beams emitted from each light source group are opened. And a light source control unit that controls the light source element so as to be guided in a predetermined direction. Therefore, it is possible to provide an image display device that can display an image in a predetermined direction and has high light utilization efficiency.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[First Embodiment]
In the first embodiment, an application example of the present invention to a light distribution control type display device will be described. Hereinafter, the light distribution control type display device according to the first embodiment will be described with reference to FIG. FIG. 3 is a diagram illustrating the light distribution control type display device according to the first embodiment.

  With reference to FIG. 3, the light distribution control type display device includes a display panel 2, an image control unit 4, a backlight unit 7, a light source control unit 8, a camera 9, and a position detection unit 10.

  The display panel 2 is a panel for displaying an image and includes a plurality of pixels. The display panel 2 is a transmissive panel that can display an image by controlling the backlight light from the backlight unit 7 for each pixel. As the display panel 2, for example, a liquid crystal panel can be used.

  The image control unit 4 is a part that controls a display image on the display panel 2 to display an image on the display panel 2. More specifically, the image control unit 4 determines the operation of each pixel of the display panel 2, more specifically, the light transmission state by each pixel.

  The backlight unit 7 outputs irradiation light that is applied to the display panel 2. The backlight unit 7 includes a light source unit 5 and a light distribution lens array 6. The backlight unit 7 is disposed behind the display panel 2 when viewed from the user. The light source unit 5 has a plurality of light source elements.

  The light source control unit 8 controls lighting of each light source of the backlight unit 7 independently. How the light source control unit 8 determines the light source to be turned on will be described later.

  A specific example of the backlight unit 7 will be described with reference to FIGS. 4 and 5. FIG. 4 is a view of the backlight unit 7 as viewed from the side. FIG. 5 is a view of the backlight unit 7 as viewed from an oblique direction. 4 and 5, the light source unit 5 in the backlight unit 7 according to the present embodiment includes an LED (light-emitting diode) 21 that is a semiconductor light source, and a light guide path 22 that receives light from the LED 21. Includes multiple combined linear light sources. The light distribution lens array 6 is a lenticular lens 23. As shown in FIG. 5, each linear light source is arranged in parallel with the direction of the main axis of the lenticular lens 23.

  Here, a mechanism for realizing light distribution will be described. Hereinafter, a plurality of linear light sources corresponding to one lens portion of the lenticular lens 23 is referred to as one block.

  The light incident on the surface (incident surface) on the light source unit 5 side of the lens has an incident angle and an incident position on the incident surface of the light and an exit angle corresponding to the lens shape, and the surface on the user side (exit surface) of the lens. Exits from. Therefore, light emitted from each light source in one block and incident on each lens is emitted from the lens at an angle determined by the positional relationship between each light source and the lens and the shape of the lens. If it says from another viewpoint, each light source contained in 1 block will be arrange | positioned so that the light which each light source radiate | emits may advance at a different angle after passing a lens.

  Therefore, the backlight unit 7 can distribute light in a predetermined direction depending on the position of the light source to be lit. For example, when the rightmost linear light source in one block in FIG. 4 is turned on, light is emitted at an angle θ1 with respect to the optical axis of the lens. The value of θ1 is determined by the positional relationship between the lens and the linear light source. When the seventh linear light source from the right end in one block is turned on, light is emitted at an angle of θ2 with respect to the optical axis of the lens.

  The light source control unit 8 controls lighting of the light source of the backlight unit 7 according to a desired emission angle. The relationship between the emission angle and the light source to be lit is determined in advance by the design of the backlight unit 7, and the light source control unit 8 determines the light source to be lit based on this relationship. The light source control unit 8 controls the lighting of the light source so that the light emitted from each light source passes through the opening and is guided in a predetermined direction.

  In addition, since the light distribution control by this apparatus is performed as mentioned above, it is preferable that the light source part 5 is arrange | positioned in the focal distance of the lenticular lens 23. FIG. At this time, since each light beam emitted from each linear light source and transmitted through the lenticular lens 23 is substantially parallel, the lenticular lens 23 emits light having very high directivity. Therefore, the light distribution control type display device according to the present embodiment can distribute light in a narrow range, for example, the position of the observer.

  Furthermore, the light distribution control type display device according to the present embodiment can perform light distribution according to the observation position of the user using the camera 9. The camera 9 captures an image of an area including the user. The position detection unit 10 detects the position of the user by performing image processing on an image captured by the camera 9. For example, the position detection unit 10 extracts a characteristic area in the image such as the contour of the user, and determines the position of the user based on the extracted area. The light source control unit 8 determines a light distribution direction and a light source to be turned on corresponding to the light distribution direction based on the positional relationship between the user and the light distribution control type display device. Thus, according to the light distribution control type display device according to the present embodiment, it is possible to perform light distribution according to the observation position of the user. When the observation position of the user changes, the light distribution direction can be made to follow the observation position.

  In particular, this light distribution control type display device can be applied to the car navigation monitor described in the prior art. In this case, the camera 9 detects the positions of the driver and the passenger on the passenger seat, and distributes light in two directions based on the detection result. In this case, a plurality of cameras 9 may be provided on the display device. In order to distribute light in two directions, for example, the light source controller 8 alternately turns on a light source that emits light emitted to the driver side and a light source that emits light emitted to the passenger seat side in time. To do. At this time, the image control unit 4 may switch and display the driver image and the passenger side image on the display panel 2 in synchronization with the light distribution. Similarly, it is also possible to distribute light in two or more directions using this light distribution control type display device.

  The light distribution control type display device according to the present embodiment also has an advantage that the light use efficiency of the light source can be improved. A normal display emits light rays over a wide range and emits useless light rays in directions other than the user. Therefore, a normal display consumes wasted power other than displaying an image to the user. According to the present invention, it is possible to suppress radiation of light rays in directions other than the user. That is, only necessary light can be generated. Therefore, a display with very low power consumption can be realized.

[Second Embodiment]
In the second embodiment, an application example of the present invention to a light beam reproduction type stereoscopic display device will be described. A stereoscopic display device according to a second embodiment will be described with reference to FIG.

  Referring to FIG. 6, the stereoscopic display device includes a stereoscopic display panel 3, an image control unit 4, a backlight unit 7, a light source control unit 8, a camera 9, and a pupil position detection unit 26.

  The stereoscopic display panel 3 displays a light reproduction type stereoscopic image. The stereoscopic display panel 3 includes a stereoscopic lens array 1 and a display panel 2. The structure of the display panel 2 is the same as that of the first embodiment. The display panel 2 displays an element image that is a source of a stereoscopic image based on a light source reproduction type stereoscopic display method. The stereoscopic lens array 1 corresponds to the lens array 13 shown in FIGS. 1 and 2. In FIG. 1 and FIG. 2, a microlens array is used as the lens array 13, but a lenticular lens is used here. In this case, although motion parallax does not occur in the vertical direction, it is considered that there is no significant effect on stereoscopic vision because the vertical motion parallax is not so much required. Of course, a microlens array may be used as the lens array 13. This configuration will be described in a third embodiment described later.

  The configuration of the image control unit 4 is the same as that described in the first embodiment. The configurations of the backlight unit 7 and the light source control unit 8 are the same as those described in the first embodiment.

  As in the first embodiment, the camera 9 captures an image of an area including the user. The pupil position detection unit 26 detects the user's pupil position by performing image processing on an image captured by the camera 9. For example, the pupil position detection unit 26 detects the pupil position of the user based on a light / dark pattern in the image.

  Based on the information from the pupil position detection unit 26, the light source control unit 8 outputs a light beam from each block of the light source unit 5 of the backlight unit 7 so as to distribute light toward a position near the user's pupil. Control. The image control unit 4 appropriately controls the display position of the element image based on information from the pupil position detection unit 26.

  The stereoscopic display device according to the present embodiment can generate a stereoscopic image having a wide area (viewing zone) where a stereoscopic image can be observed and a high resolution. This will be described below.

  First, the viewing area in the light beam reproduction method will be described with reference to FIGS. FIG. 7 is a diagram illustrating the viewing zone angle of light passing through one lens. As shown in FIG. 7, an element image area 15 for displaying an element image is set corresponding to the lens array 13. The image of the element image area 15 can be observed in an area within the viewing zone angle 16. FIG. 8 is a diagram showing the viewing zone. A region where the element image can be observed through all the lenses of the lens array 13 is a viewing zone 17. In order not to limit the observation position of the user, the viewing zone 17 is preferably as wide as possible.

  As one method for widening the viewing zone 17, it is conceivable to widen the viewing zone angle 16. However, when the viewing zone angle 16 is widened, the resolution of the stereoscopic image is lowered. The reason is as follows. In order to widen the viewing zone angle 16, it is necessary to increase the area of each lens, and it is necessary to reduce the number of lenses in the lens array 13. On the other hand, in the stereoscopic display device using the light beam reproduction method, a stereoscopic image is displayed through the lens array 13, and the user observes an image of 1 to 2 pixels through one lens. Is equivalent to the resolution (number of lenses) of the lens array.

  The resolution of the stereoscopic image will be described using numerical values. For example, if the resolution of the display panel is 200 × 200 pixels and the element image is 10 × 10 pixels, the number of lenses in the lens array is 20 × 20, which is equivalent to the resolution of the stereoscopic image. Note that the number of pixels in the element image region represents the number of parallaxes that can be displayed (the number of motion parallaxes). In this case, the number of motion parallax is 10 parallaxes on the left and right and 10 parallaxes on the top and bottom.

  The reduction in resolution when the viewing zone angle 16 is widened can be solved to some extent by increasing the number of pixels of the display panel. For example, in the above example, if the resolution of the display panel is 400 × 400 pixels, the lens array 13 having the number of lenses of 40 × 40 may be used while the number of pixels of the element image is maintained at 10 × 10 pixels. it can. However, there is a limit to the number of pixels in the display panel, and there is a limit to improving the resolution by this method. For example, in order to obtain a stereoscopic image of the Super Video Graphics Array (SVGA) level (800 × 600 pixels), which is normal in a two-dimensional display, the number of lenses in the lens array 13 is required to be 800 × 600, and an element image Even if 10 × 10 pixels are used, 8000 × 6000 pixels are required as a display panel. However, there is currently no direct view display that can display such a display. In addition, it is not practical to develop such a display because there are many technical or cost issues.

  As another method of expanding the viewing zone 17, there is a method of controlling an image displayed on the display panel. According to this method, it is possible to compensate for the reduced viewing angle while using a lens array having a large number of lenses in order to ensure the resolution of a stereoscopic image. This method will be described with reference to FIGS.

  FIG. 9 is a diagram showing a viewing zone angle when using a lens array 13a which is smaller than the lens array 13 of FIG. 7 and has a large number of lenses. In this case, the viewing zone angle is the viewing zone angle 16a shown in FIG. 9, which is naturally narrower than the viewing zone angle 16 of FIG. In this case, the user can observe the display image at the user position a, but cannot observe at the observation position b or the observation position c.

  In order to allow the user to observe the display image at the observation positions b and c, as shown in FIG. 10, the element image area 15 may be enlarged to the element image area 15a as shown in FIG. That is, the element image may be displayed in the area b when the user is at the observation position b, and the element image may be displayed in the area c when the user is at the observation position c. Thus, the viewing zone angle can be enlarged by changing the region for displaying the element image according to the position of the user without fixing the region.

  Explaining in accordance with the present embodiment, the image control unit 4 controls the element image displayed on the display panel 2 based on the detection result of the pupil position detection unit 26. The light source control unit 8 controls the light distribution of the backlight unit 7 so that the element image is projected onto a region including the user's pupil.

  FIG. 10 shows a case where the viewing zone covers both eyes of the user at the observation position. In order to further improve the resolution of the stereoscopic image, the viewing area can be viewed as much as one eye of the user. The range angle can be narrowed down.

  In this case, it is not possible to view stereoscopically only by changing the display area of the element image according to the position of the user, and a mechanism for realizing image separation for the left and right eyes, that is, while displaying an image for one eye A mechanism that prevents the image from being projected onto the other eye is necessary. This is because, in the light ray reproduction method, if the viewing area covers both eyes of the user, binocular parallax can be obtained by different light rays seen by the right eye / left eye. When the corner covers only one eye of the user, the display image is an image for projecting to one eye, and binocular parallax cannot be obtained even if this is projected to the other eye It is.

  In the case of the light beam reproduction method, it is difficult to perform image separation for the left and right eyes with a parallax barrier or a lenticular lens such as a two-lens type, and a method of performing image separation for the left and right eyes in a time division manner is preferable. This method is also adopted in the present embodiment.

  A mechanism that enables stereoscopic viewing by the stereoscopic display device according to the present embodiment will be described in more detail. The stereoscopic display panel 3 that is a light-reproducing panel is designed so that the viewing area is narrowed down to one eye of the user in order to improve the resolution of the stereoscopic image.

  The stereoscopic display device separates the images for the left and right eyes in a time-sharing manner so that the image is not projected to the other eye while displaying the image for one eye. That is, the image control unit 4 alternately displays the right-eye image and the left-eye image on the display panel 2 such that the right-eye image is displayed for a certain period and the left-eye image is displayed for the next period. To do. Further, the image control unit 4 changes the display area of the element image based on the position of the user's pupil based on the information from the pupil position detection unit 26.

  The light source control unit 8 controls the backlight unit 7 and distributes the backlight to the right eye of the user based on the information from the pupil position detection unit 26 during the right-eye image display period. During the left-eye image display period, the backlight is distributed to the left eye of the user based on information from the pupil position detection unit 26.

  As described above, according to the stereoscopic display device according to the present embodiment, the time division display of the left and right images and the light distribution control of the backlight are executed in a coordinated manner, while the one-eye image is being displayed. The image can be prevented from being projected onto the eyes. Through this series of coordinated controls, the user can perceive a light-reproducing high-resolution stereoscopic display image over a wide viewing area. Furthermore, it is possible to achieve both the resolution of the stereoscopic image and the expansion of the viewing zone angle in the stereoscopic video display device.

[Third Embodiment]
Another application example to the light beam reproduction type stereoscopic display device of the present invention will be described. The configuration of the stereoscopic display device according to the third embodiment is basically the same as that of the first embodiment. However, the stereoscopic display device according to the third embodiment uses a microlens array in which lenses are two-dimensionally arranged instead of a lenticular array as the stereoscopic lens array 1. In this case, a vertical motion parallax that is not obtained in the second embodiment is also obtained for the stereoscopic image.

  As the stereoscopic lens array 1 is a microlens array, the pupil position detection unit 26 needs to detect the user's pupil position not only in the horizontal direction but also in the vertical direction. In addition, the image control unit 4 needs to change the display image position also in the vertical direction. Further, the light source control unit 8 needs to execute light distribution control of the backlight unit 7 two-dimensionally in the vertical and horizontal directions.

  The backlight part 7 which concerns on 3rd Embodiment is demonstrated using FIG. In the third embodiment, a microlens array 25 is arranged as the light distribution lens array 6 instead of the light distribution lenticular lens described in the first embodiment. Moreover, LED21 which is a semiconductor light source is arrange | positioned two-dimensionally as a light source element. For the same reason as described in the first embodiment, the LED 21 is preferably disposed at the focal length of the microlens array 25.

  Here, a mechanism of light distribution in the third embodiment will be described. Hereinafter, a plurality of light sources corresponding to one lens portion of the microlens are referred to as one block. In FIG. 11, 6 × 6 LEDs 21 are one block.

  For example, when the LED-A in one block in FIG. 11 is turned on, the light in the direction determined by the positional relationship between the LED-A and the lens, that is, the angle θ3 with respect to the optical axis z of the lens, and xy Light that is inclined so that the angle with respect to the y-axis when projected onto a plane is represented by θ4 is emitted. Similarly, when LED-B is turned on, similarly, light inclined at an angle of θ5 with respect to the optical axis z of the lens and an angle with respect to the y-axis when projected onto the xy plane is represented by θ6. Emitted.

  The light source control unit 8 can distribute light in a two-dimensional manner in a direction determined by the position of the light source to be lit by independently controlling lighting of each light source of the backlight unit 7. Based on the information from the pupil position detection unit 26, the light source control unit 8 can distribute the light beams from each block of the backlight unit 7 toward the pupil position of the user. In synchronization with the lighting control, the image control unit 4 appropriately controls the display position of the element image based on the information from the pupil position detection unit 26.

  Similar to the first and second embodiments, the light source is preferably arranged in the vicinity of the focal length of the microlens. At this time, the light emitted from each light source element and emitted from the microlens is substantially parallel, and the light emitted from the display device has a very strong directivity. Therefore, the display device can distribute light in a narrow range of a position near the user's pupil.

  According to the stereoscopic display device according to the present embodiment, in addition to the effects produced by the stereoscopic display device according to the second embodiment, a stereoscopic display image that can obtain motion parallax in the vertical direction can be obtained.

[Fourth Embodiment]
In the second embodiment and the third embodiment, the three-dimensional image reproduction method has been described as the light ray reproduction method, but other methods can also be supported. Here, a twin-lens stereoscopic display device will be described. As already described, the principle of the binocular stereoscopic vision is to display images for the left eye and the right eye for the left and right eyes of the user, respectively. According to the stereoscopic display device according to the present embodiment, the right-eye image and the left-eye image are displayed in a time-sharing manner, and the light distribution control is performed on the right eye and the left eye in synchronization with the display.

  FIG. 12 shows a configuration of the stereoscopic display device according to this embodiment. This is obtained by omitting the stereoscopic lens array 1 from the stereoscopic display devices according to the second embodiment and the third embodiment.

  According to the twin-lens stereoscopic display device having this configuration, the left and right images are displayed on the display panel 2 in a time-sharing manner, and the backlight unit 7 determines the position of the user's pupil detected by the pupil position detection unit 26. By distributing light to the left and right eyes in synchronization with the image, the left and right images can be separated. Therefore, according to this stereoscopic display device, a binocular stereoscopic display can be realized.

  Conventionally, the left and right images are spatially separated by a parallax barrier or lenticular lens. In this method, since the right-eye image and the left-eye image are displayed at the same time, the number of pixels of each image is half the number of pixels of the display panel, and therefore the display resolution of the stereoscopic image is also half of the display resolution of the display panel. descend.

  As a conventional method for maintaining the resolution, there has been a method in which left and right images are displayed in a time-sharing manner, and the left and right images are separated by the user using glasses with left and right eye shutters synchronized with the display of the left and right images. . However, this method requires the user to wear glasses, and the structure of the glasses tends to be complicated, which places a burden on the user.

  According to the stereoscopic display device according to the present embodiment, the right-eye and left-eye images are displayed in a time-sharing manner, so that the number of pixels of the display panel can be maintained, and the user needs to wear glasses or the like. There is no. Therefore, the user can observe a high-resolution stereoscopic image without glasses.

[Others]
In each of the above embodiments, when the observation position of the stereoscopic image is designated in advance, the backlight is designed so as to distribute light to the right eye and the left eye of the user at the designated position, and the image If the display is performed at the designated position, the camera 9 and the position detector 10 (or the pupil position detector 26) can be omitted.

  Moreover, the example which used LED which is a semiconductor light emitting element as a light source was shown. Since the LED is small compared to a cold cathode tube (CCFL) often used as a backlight of a liquid crystal panel, it is easy to mount the LED. In addition, since the response speed is high, it is possible to cope with time-division lighting control. Furthermore, the drive circuit can be easily realized. From these reasons, it is preferable to use an LED. However, the light source element in the present invention is not limited to the LED.

  What combined each embodiment suitably is also contained in this invention. For example, in the first embodiment, the pupil position detection unit 26 may be used instead of the position detection unit 10. Alternatively, in the first embodiment, the backlight unit 7 may be replaced with that of the third embodiment. The display device thus replaced can also perform light distribution in the vertical direction.

  In the above embodiment, an example in which the present invention is used as a display device has been described. However, the present invention is an illumination device capable of controlling the direction of light, for example, an automobile light or illumination that illuminates a person's position. It can also be used as an instrument or a spotlight. That is, the combination of the backlight unit 7 and the light source control unit 8 in the embodiment may be used as the lighting device.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is the figure which looked at the optical system of the stereoscopic image display apparatus using a light source reproduction method from the side. It is a perspective view of the optical system of the three-dimensional video display apparatus using a light source reproduction method. It is a figure which shows the light distribution control type display apparatus which concerns on 1st Embodiment. It is the figure which looked at the backlight part 7 from the side surface direction. It is the figure which looked at the backlight part 7 from diagonally. It is a figure which shows the three-dimensional display apparatus which concerns on 2nd Embodiment. It is a figure which shows the viewing zone angle of the light which passes through one lens. It is a figure which shows a visual field. It is a figure which shows a viewing zone angle at the time of using the lens array 13a which is small compared with the lens array 13 of FIG. 7, and has many lenses. It is a figure which shows the viewing zone angle at the time of enlarging an element image area | region. It is a figure which shows the backlight part 7 which concerns on 3rd Embodiment. It is a figure which shows the three-dimensional display apparatus which concerns on 4th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Stereoscopic lens array, 2 Display panel, 3 Stereo display panel, 4 Image control part, 5 Light source part, 6 Light distribution lens array, 7 Backlight part, 8 Light source control part, 9 Camera, 10 Position detection part, 11 reproduction image, 12 display panel, 13 lens array, 13a lens array, 14 element image, 15 element image area, 15a element image area, 16 viewing zone angle, 16a viewing zone angle, 17 viewing zone, 22 light guide path, 23 lenticular Lens, 25 micro lens array, 26 pupil position detector.

Claims (16)

An image display unit having a plurality of pixels;
A light source unit including a plurality of light source groups each including a plurality of light source elements;
A light source control unit capable of independently controlling each of the light source elements;
A light guide unit that is disposed between the image display unit and the light source unit, has a plurality of openings corresponding to the plurality of light source groups, and guides the transmitted light to illuminate the image display unit. And
The image display device, wherein the light source control unit controls each light source element so that light emitted from each light source group passes through the opening and is guided in a predetermined direction.   The video display device according to claim 1, wherein the light beam guided through each of the openings of the light guide unit is substantially parallel light.   The video display device according to claim 1, wherein the light source control unit controls each of the light source elements independently so as to guide light in a plurality of predetermined directions. It further comprises a position detector that detects the position of the observer,
4. The light source controller according to claim 1, wherein the light source control unit turns on the light source element capable of emitting a light beam traveling in the direction of the observer based on the position of the observer detected by the position detection unit. The video display device according to item. A pupil position detector for detecting the position of the observer's pupil;
4. The light source control unit according to claim 1, wherein the light source control unit turns on the light source element capable of emitting a light beam traveling in the direction of the pupil based on the position of the pupil detected by the pupil position detection unit. The video display device according to item.   The video display device according to claim 3, wherein the light guide unit is a lens array having a plurality of lenses.   The video display device according to claim 6, wherein each of the light source elements is disposed at a substantially focal length of the lens array.   The image display device according to claim 6, wherein the lens array is a lenticular lens.   The image display device according to claim 6, wherein the lens array is a two-dimensional lens array in which the plurality of lenses are arranged on lattice points of a planar lattice.   The video display device according to claim 3, wherein each of the light source elements is a semiconductor light emitting element. Each light source element is a semiconductor light emitting element,
The video display device according to claim 8, wherein the light source unit further includes a linear light guide plate arranged along a lens axis direction of the lenticular lens.   The video display device according to claim 3, further comprising a light direction limiting unit that limits a traveling direction of the light transmitted through each of the pixels.   The video display device according to claim 12, wherein the image display unit displays an image according to a light reproduction type stereoscopic display system.   The video display device according to claim 12, wherein the light direction limiting unit is a lenticular lens.   The video display device according to claim 12 or 13, wherein the light direction limiting unit is a two-dimensional lens array in which a plurality of lenses are arranged on lattice points of a planar lattice. An image control unit that controls the image display unit so that the image display unit temporally divides and displays a plurality of images;
The video display device according to claim 1, wherein the light source control unit controls lighting of each of the light source elements in synchronization with display of the plurality of images.

Images