Abstract:
A display device includes a two-dimensional display section configured to display parallax images for stereoscopic display, a variable parallax barrier configured to form a plurality of different barrier patterns, each barrier pattern having light transmitting portions and light blocking portions, and at least one timing controller for controlling a first switching operation in the two-dimensional display section and a second switching operation in the variable parallax barrier.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to Japanese Priority Patent Application JP 2009-130912 filed on May 29, 2009, the entire content of which is hereby incorporated by reference. 
       BACKGROUND 
       [0002]    The present disclosure relates to a stereoscopic display and a stereoscopic display method which are allowed to achieve stereoscopic display by a parallax barrier system. 
         [0003]    In related art, as one of stereoscopic display systems which are allowed to achieve stereoscopic vision with naked eyes without wearing special glasses, a parallax barrier system or lenticular system stereoscopic display is known.  FIG. 11  illustrates a typical configuration example of the parallax barrier system stereoscopic display. In the stereoscopic display, a parallax barrier  101  is arranged so as to face a front surface of a two-dimensional display panel  102 . In a typical configuration of the parallax barrier  101 , shielding sections  111  shielding display image light from the two-dimensional display panel  102  and stripe-shaped slit sections  112  allowing the display image light to pass therethrough are alternately arranged in a horizontal direction. As the two-dimensional display panel  102 , a two-dimensional display panel with a pixel configuration in which a plurality of pixels configured of sub-pixels of a plurality of colors (R, G and B) are two-dimensionally arranged is used. For example, as illustrated in  FIG. 12 , a pixel arrangement in which sub-pixels of different colors are periodically arranged in lines in a horizontal direction, and sub-pixels of the same color are arranged in one line in a vertical direction is used. 
         [0004]    In the parallax barrier system or lenticular system stereoscopic display, a plurality of parallax images including different parallax information, respectively, are prepared, and, for example, each of the parallax images are separated into a plurality of stripe-shaped separated images extending in a vertical direction. Then, the separated images of the plurality of parallax images are alternately arranged in a horizontal direction so as to produce a composite image including a plurality of stripe-shaped parallax images in one screen, and the composite image is displayed on the two-dimensional display panel  102 . In the case of the parallax barrier system, the composite image displayed on the two-dimensional display panel  102  is viewed through the parallax barrier  101 . When the widths of the separated images to be displayed, a slit width in the parallax barrier  101  and the like are appropriately set, in the case where a viewer watches the stereoscopic display from a predetermined position and a predetermined direction, light rays from different parallax images are allowed to enter into right and left eyes  10 R and  10 L of the viewer, respectively, through the slit sections  112 . Thus, when the viewer watches the stereoscopic display from a predetermined position and a predetermined direction, a stereoscopic image is perceived. 
         [0005]    To achieve stereoscopic vision, it is necessary for the right and left eyes  10 R and  10 L to view different parallax images, respectively, so two or more parallax images, that is, an image for right eye and an image for left eye are necessary. In the case where three or more parallax images are used, multi-view vision is achievable. When more parallax images are used, stereoscopic vision in response to changes in viewing position of the viewer is achievable. That is, motion parallax is obtained. 
         [0006]    In both cases of a parallax barrier system and a lenticular system, images of which the number is equal to the number of parallaxes are spatially separated and displayed in one screen, so compared to the case where two-dimensional display is performed, resolution is reduced by a factor of the number of parallaxes. Japanese Patent No. 3096613 discloses an invention for improving resolution by alternately displaying images for right eye and images for left eye in both of a horizontal direction and a vertical direction in a parallax barrier system stereoscopic display. However, the fact remains that the images for right eye and the images for left eye are spatially separated and displayed, so resolution is still reduced. There is disclosed an invention in which optimum stereoscopic vision corresponding to a viewing position is achievable in a parallax barrier system stereoscopic display by dynamically changing a barrier pattern of a parallax barrier depending on the viewing position in “Advances in the Dynallax Solid-State Dynamic Parallax Barrier Autostereoscopic Visualization Display System” Peterka, T.; Kooima, R. L.; Sandin, D. J.; Johnson, A.; Leigh, J.; DeFanti, T. A. Visualization and Computer Graphics, IEEE Transactions on Volume 14, Issue 3, May/June 2008 Page(s): 487-499. However, vision corresponding to the viewing position is allowed to be improved, but resolution is not improved. 
         [0007]    It is therefore desirable to provide a stereoscopic display and a stereoscopic display method which are allowed to prevent a decline in resolution during stereoscopic display by a parallax barrier system. 
       SUMMARY 
       [0008]    In the stereoscopic display and the stereoscopic display method according to an embodiment, the parallax images are combined into a one-screen image according to a predetermined pattern while maintaining such a state that the parallax images are spatially separated from each other, and the display pattern configured of the parallax images are displayed while periodically switching different display patterns from one to another. In other words, the parallax images which are spatially and temporally separated from each other are displayed on the two-dimensional display section. The switching timing of the barrier pattern and the switching timing of the display pattern are synchronized so that stereoscopic vision is achievable. 
         [0009]    In the stereoscopic display and the stereoscopic display method according to an embodiment, the display pattern configured of the parallax images is periodically switched, and the barrier pattern is periodically switched in synchronization with periodically switching the display pattern, so the parallax images which are spatially and temporally separated are displayed on the two-dimensional display section so that stereoscopic display is achievable. Thereby, compared to the case where the parallax images which are spatially separated are displayed in one display pattern, a decline in resolution in stereoscopic display is preventable. 
         [0010]    In an embodiment, a display device includes a two-dimensional display section configured to display parallax images for stereoscopic display, a variable parallax barrier configured to form a plurality of different barrier patterns, each barrier pattern having light transmitting portions and light blocking portions, and at least one timing controller for controlling a first switching operation in the two-dimensional display section and a second switching operation in the variable parallax barrier. 
         [0011]    In an embodiment, a display device includes a liquid crystal display panel configured to display parallax images for stereoscopic display, a variable parallax barrier configured to form a plurality of different barrier patterns, each barrier pattern having light transmitting portions and light blocking portions, at least one timing controller for controlling a first switching operation in the liquid crystal display panel and a second switching operation in the variable parallax barrier, and a backlight configured to emit light through the liquid crystal display panel and the variable parallax barrier. 
         [0012]    In another embodiment, a method of displaying a stereoscopic image includes displaying parallax images for stereoscopic display with a two-dimensional display section, forming a plurality of different barrier patterns with a variable parallax barrier, each barrier pattern having light transmitting portions and light blocking portions, and controlling a first switching operation in the two-dimensional display section and a second switching operation in the variable parallax barrier. 
         [0013]    In another embodiment, a method of displaying a stereoscopic image, the method includes displaying parallax images for stereoscopic display with a liquid crystal display panel, forming a plurality of different barrier patterns with a variable parallax barrier, each barrier pattern having light transmitting portions and light blocking portions, controlling a first switching operation in the liquid crystal display panel and a second switching operation in the variable parallax barrier, and emitting light from a backlight through the liquid crystal display panel and the variable parallax barrier. 
         [0014]    Additional features and advantages are described herein, and will be apparent from the following Detailed Description and the figures. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0015]      FIG. 1  is a configuration diagram of a stereoscopic display according to a first embodiment. 
           [0016]      FIG. 2  is a block diagram illustrating a circuit responsible for display control in the stereoscopic display according to the first embodiment. 
           [0017]      FIG. 3  is a plan view illustrating a pixel arrangement of a liquid crystal display panel in the stereoscopic display according to the first embodiment. 
           [0018]      FIG. 4  is a plan view illustrating a first barrier pattern and a second barrier pattern in the stereoscopic display according to the first embodiment, respectively. 
           [0019]      FIG. 5  is a plan view illustrating a first display pattern and a second display pattern of a parallax image in the stereoscopic display according to the first embodiment, respectively. 
           [0020]      FIG. 6  is a plan views illustrating a first parallax image viewed through the first barrier pattern in a first display period and the first parallax image viewed through the second barrier pattern in a second display period in the stereoscopic display according to the first embodiment, respectively. 
           [0021]      FIGS. 7A and 7B  are schematic explanatory diagrams illustrating a state where stereoscopic vision is achieved in the first display period and a state where stereoscopic vision is achieved in the second display period in the stereoscopic display according to the first embodiment, respectively. 
           [0022]      FIG. 8  is a timing chart in the stereoscopic display according to the first embodiment, a part A in  FIG. 8  illustrates transition of a display pattern in an arbitrary pixel position, and a part B in  FIG. 8  illustrates transition of a barrier pattern in a position corresponding to the pixel position in the part A in  FIG. 8 . 
           [0023]      FIG. 9  is a block diagram illustrating a circuit responsible for display control in a stereoscopic display according to a second embodiment. 
           [0024]      FIG. 10  is a timing chart in the stereoscopic display according to the second embodiment, a part A in  FIG. 10  illustrates transition of a display pattern in an arbitrary pixel position, a part B in  FIG. 10  illustrates transition of a barrier pattern in a position corresponding to the pixel position in the part A in  FIG. 10 , and a part C in  FIG. 10  illustrate transition of a lighting pattern of a backlight. 
           [0025]      FIG. 11  is a configuration diagram illustrating a typical configuration example of a parallax barrier system stereoscopic display. 
           [0026]      FIG. 12  is a plan view illustrating an example of a typical pixel arrangement of a two-dimensional display panel. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Preferred embodiments will be described in detail below referring to the accompanying drawings. 
       First Embodiment 
     Configuration of Stereoscopic Display 
       [0028]      FIG. 1  illustrates a whole configuration example of a stereoscopic display according to a first embodiment.  FIG. 2  illustrates a circuit responsible for display control in the stereoscopic display. As illustrated in  FIG. 1 , the stereoscopic display includes a liquid crystal display panel  2 , a backlight  3  arranged on a back surface of the liquid crystal display panel  2 , and a switching liquid crystal panel  1  arranged so as to face a display surface of the liquid crystal display panel  2 . As illustrated in  FIG. 2 , the stereoscopic display further includes a timing controller  21  for controlling a display operation in the liquid crystal display panel  2  and a parallax image data output section  23 . Moreover, the stereoscopic display includes a timing controller  22  for controlling a switching operation in the switching liquid crystal panel  1  and a barrier pixel data output section  24 . 
         [0029]    In the embodiment, the liquid crystal display panel  2  and the backlight  3  correspond to specific examples of “a two-dimensional display section.” Moreover, the switching liquid crystal panel  1  corresponds to a specific example of “a variable parallax barrier.” The timing controllers  21  and  22  correspond to specific examples of “a synchronization control section” in the invention. 
         [0030]      FIG. 3  illustrates an example of a pixel configuration of the liquid crystal display panel  2 . The liquid crystal display panel  2  has a pixel configuration in which a plurality of sub-pixels  4 R,  4 G and  4 B of three colors R (red), G (green) and B (blue) necessary for color display are two-dimensionally arranged. In an configuration example in  FIG. 3 , a combination of sub-pixels  4 R,  4 G and  4 B of the three color connected to one another in a longitudinal direction constitutes a unit pixel (1 pixel)  4 . As illustrated in  FIG. 3 , a pixel arrangement in which sub-pixels of different colors are periodically arranged in lines in a vertical direction (a longitudinal direction) and sub-pixels of the same color are arranged in one line in a horizontal direction (a transverse direction) is used. The liquid crystal display panel  2  two-dimensionally displays an image by modulating light emitted from the backlight  3  in each of the sub-pixels in such a pixel configuration. The liquid crystal display panel  2  displays parallax images for stereoscopic display outputted from the parallax image data output section  23  in response to control by the timing controller  21 . 
         [0031]    In addition, to achieve stereoscopic vision, it is necessary for a right eye  10 R and a left eye  10 L to view different parallax images, respectively, so two parallax images, that is, an image for right eye and an image for left eye, or more parallax images are necessary. In the case where three or more parallax images are used, multi-view vision is achievable. In the embodiment, description will be given referring to a display example by a binocular system using two parallax images. 
         [0032]    The liquid crystal display panel  2  combines two parallax images for right eye and left eye into a one-screen image according to a predetermined display pattern, and displays the display pattern configured of the parallax images. The liquid crystal display panel  2  displays the display pattern configured of the two parallax images while periodically switching two different kinds of display patterns, in which the display positions of the two parallax images are different, from one to the other. Image data corresponding to each display pattern is outputted from the parallax image data output section  23 . The timing controller  21  controls a timing of displaying each of the display patterns. 
         [0033]      FIG. 5  illustrates an example of the two display patterns. In this case, in  FIG. 5 , pixels (R 1 , G 1 , B 1 ) are pixels for displaying a first parallax image (for example, an image for right eye), and pixels (R 2 , G 2 , B 2 ) are pixels for displaying a second parallax image (for example, an image for left eye). In both of parts A and B in  FIG. 5 , stripe-shaped first parallax images and stripe-shaped second parallax images extending in a longitudinal direction are alternately arranged in a horizontal direction. However, the first second parallax images and the second parallax images exchange display pixel positions with each other between the first display pattern in the part A in  FIG. 5  and the second display pattern in the part B in  FIG. 5 . For example, the pixels (R 1 , G 1 , B 1 ) to which the first parallax images are allocated in the first display pattern in the part A in  FIG. 5  are changed to the pixels (R 2 , G 2 , B 2 ) in the second display pattern in the part in  FIG. 5 , and the second parallax images are allocated to the pixels (R 2 , G 2 , B 2 ). 
         [0034]    The switching liquid crystal panel  1  includes a plurality of pixels which are two-dimensionally arranged, and is allowed to perform a switching operation of switching each of the pixels between a state where the pixel allows light to pass therethrough and a state where the pixel does not allow light to pass therethrough. The switching liquid crystal panel  1  achieves a function as a variable parallax barrier. The switching liquid crystal panel  1  forms a barrier pattern for optically separating each of the parallax images displayed on the liquid crystal display panel  2  so as to allow stereoscopic vision. The switching liquid crystal panel  1  forms two kinds of barrier patterns corresponding to two display patterns of the parallax images illustrated in  FIG. 5  by periodically switching two states of the barrier pattern. 
         [0035]      FIG. 4  illustrates examples of the two barrier patterns. The barrier patterns are patterns each including a shielding section  11  shielding display image light from the liquid crystal display panel  2  and a slit section  12  allowing the display image light to pass therethrough. A part in  FIG. 4  illustrates a first barrier pattern corresponding to the first display pattern in the part A in  FIG. 5 , and a part B in  FIG. 4  illustrates a second barrier pattern corresponding to the second display pattern in the part B in  FIG. 5 . In other words, the first barrier pattern optically separates the display image light so as to allow stereoscopic vision when the parallax images in the first display pattern are displayed. The second barrier pattern optically separates the display image light so as to allow stereoscopic vision when the parallax images in the second display pattern are displayed. The shape of the slit section  12  in each of the barrier patterns is set to an appropriate shape for allowing light rays from different parallax images to enter into right and left eyes  10 R and  10 L of a viewer, respectively, when the viewer watches the stereoscopic display from a predetermined position and a predetermined direction. 
         [0036]    Pixel data for forming each of the barrier patterns in the switching liquid crystal panel  1  is outputted from the barrier pixel data output section  24 . The timing controller  22  controls, based on a frame signal, a timing of forming each of the barrier patterns in the switching liquid crystal panel  1  (a timing of changing each pixel into the state where the pixel allows light to pass therethrough or the state where the pixel does not allow light to pass therethrough). Image data of each of the display patterns displayed on the liquid crystal display panel  2  is outputted from the parallax image data output section  23 , and a frame signal obtained at the time of switching the display pattern is outputted to the timing controller  22  through the barrier pixel data output section  24 . The timing controller  22  performs synchronous control to synchronize a switching timing of the barrier pattern and a switching timing of the display pattern in the liquid crystal display panel  2 . In addition, as will be described later referring to  FIG. 8 , synchronous control is preferably performed by the timing controller  22  in consideration of a difference in liquid crystal response speed between the liquid crystal panel  1  and the liquid crystal display panel  2 . 
         [0037]    Operation of Stereoscopic Display 
         [0038]    In the stereoscopic display, in the liquid crystal display panel  2 , parallax images are combined into a one-screen image according to a predetermined pattern while maintaining such a state that the parallax images are spatially separated from each other, and the parallax images are displayed while periodically switching the display pattern. In other words, the parallax images which are spatially and temporally separated are displayed on the liquid crystal display panel  2 . In the switching liquid crystal panel  1 , different barrier patterns are periodically switched from one to another in synchronization with switching the display pattern so as to provide stereoscopic vision. 
         [0039]      FIG. 7A  schematically illustrates a state where stereoscopic vision is achieved in a first display period T 1 .  FIG. 7B  schematically illustrates a state where stereoscopic vision is achieved in a second display period T 2  which is different from the first display period T 1 . In the first display period T 1 , the first display pattern (refer to the part A in  FIG. 5 ) is displayed on the liquid crystal display panel  2 , and the first barrier pattern (refer to the part A in  FIG. 4 ) is formed on the switching liquid crystal panel  1 . In the second display period T 2 , the second display pattern (refer to the part B in  FIG. 5 ) is displayed on the liquid crystal display panel  2 , and the second barrier pattern (refer to the part B in  FIG. 4 ) is formed on the switching liquid crystal panel  1 . 
         [0040]    In  FIGS. 7A and 7B , the right eye  10 R and the left eye  10 L of the viewer are defined as viewpoints  1  and  2 , respectively. In the first display period T 1 , first parallax images (images for right eye) and second parallax images (images for left eye) are alternately allocated to pixels (refer to (R 1 , G 1 , B 2 ) in the part A in  FIG. 5 ) for the viewpoint  1  and pixels (refer to (R 2 , G 2 , B 2 ) in the part A in  FIG. 5 ) for the viewpoint  2  according to the first display pattern, and then displayed on the liquid crystal display panel  2 . When such displayed images are viewed through the first barrier pattern formed by the switching liquid crystal panel  1 , the right eye  10 R perceives only light from the first parallax images, and the left eye  10 L perceives only light from the second parallax images. Thereby, a stereoscopic image based on the first parallax images and the second parallax images is perceived in the first display period T 1 . 
         [0041]    In the second display period T 2 , the first parallax images and the second parallax images are alternately allocated to pixels (refer to (R 1 , G 1 , B 1 ) in the part B in  FIG. 5 ) for the viewpoint  1  and pixels (refer to (R 2 , G 2 , B 2 ) in the part B in  FIG. 5 ) for the viewpoint  2  according to the second display pattern, and then displayed on the liquid crystal display panel  2 . When such displayed images are viewed through the second barrier pattern formed by the switching liquid crystal panel  1 , the right eye  10 R perceives only light from the first parallax images, and the left eye  10 L perceives only light from the second parallax images. Thereby, also in the second display period T 2 , a stereoscopic image based on the first parallax images and the second parallax images are perceived. 
         [0042]    A part A in  FIG. 6  illustrates the first parallax images viewed by the right eye  10 R of the viewer through the first barrier pattern in the first display period T 1 . A part B in  FIG. 6  illustrates the first parallax images viewed by the right eye  10 R of the viewer through the second barrier pattern in the second display period T 2 . As a result, the first parallax images are displayed using all pixels on the liquid crystal display panel  2  through the first display period T 1  and the second display period T 2 . Therefore, when the first parallax images are displayed, a decline in spatial resolution is prevented. The same holds true for the second parallax images viewed by the left eye  10 L. 
         [0043]    In general, there is a difference in response speed of liquid crystal between the liquid crystal display panel  2  for displaying an image and the switching liquid crystal panel  1  for simply controlling switching between transmission and non-transmission, and the response speed of liquid crystal in the liquid crystal display panel  2  is slower. Therefore, in the case where a switching timing of the display pattern in the liquid crystal display panel  2  and a switching timing of the barrier pattern in the switching liquid crystal panel  1  are synchronized, synchronous control based on a difference in response speed is preferably performed. 
         [0044]      FIG. 8  illustrates a timing chart, and a part A in  FIG. 8  illustrates transition of a display pattern in an arbitrary pixel position in the liquid crystal display panel  2  and a part B in  FIG. 8  illustrates transition of a barrier pattern in a position corresponding to the pixel position in the part A in  FIG. 8  in the switching liquid crystal panel  1 . In a first pixel position, at a first timing, a first region on the switching liquid crystal panel  1  is turned into a transmittance state (the slit section  12 ) so that a pixel for the viewpoint  1  is shown to the viewpoint  1 . At the next timing, that is, a second timing, the first region on the switching liquid crystal panel  1  is turned into a non-transmittance state (the shielding section  11 ). At this time, the first pixel position is changed to a pixel for the viewpoint  2 . 
         [0045]    In this case, as illustrated in the part A in  FIG. 8 , in the first pixel position on the liquid crystal display panel  2 , an image for the viewpoint  1  is displayed in a period from a time t 10  to a time t 20 , and an image for the viewpoint  2  is displayed in the next period, that is, a period from a time t 30  to a time t 40 . The image for the viewpoint  1  starts to be displayed at the time t 10 , but the image starts to be displayed with full stability from a time t 11  which is behind the time t 10  by a predetermined period due to the response speed of liquid crystal. As illustrated in the part B in  FIG. 8 , synchronous control is performed so that the first region on the switching liquid crystal panel  1  is turned into the transmittance state at the time t 11  at which the image is stably displayed. In the next period from the time t 30  to the time t 40 , synchronous control is performed so that the first region on the switching liquid crystal panel  1  is turned into the non-transmittance state at the time t 30  without setting a delay period. 
         [0046]    Thus, in the case of switching the barrier pattern, a switching timing of the barrier pattern so that the shielding section  11  is turned into the slit section  12  is delayed as compared to a switching timing of the display pattern in the liquid crystal display panel  2 . Thereby, the viewer is allowed to view a parallax image displayed on the liquid crystal display panel  2  at a more stable timing. Moreover, in the switching liquid crystal panel  1 , the period of the non-transmittance state is longer than the period of the transmittance state. Thereby, a displayed image is shielded in a transition period in which the displayed image is changed in the liquid crystal display panel  2  so as not to be viewed, thereby a stable stereoscopic image is allowed to be viewed. For example, a mixture of two parallax images is prevented from being viewed in the transition period. In addition, the timing controller  22  (refer to  FIG. 2 ) performs timing control on the barrier pattern in response to a frame signal outputted from the parallax image data output section  23 . 
       EFFECT IN FIRST EMBODIMENT 
       [0047]    In the first embodiment, the display pattern configured of the parallax images is periodically switched, and the barrier pattern is periodically switched in synchronization with switching the display pattern, so the parallax images which are spatially and temporally separated are displayed on the two-dimensional display section so that stereoscopic display is achievable. Thereby, compared to the case where the parallax images which are spatially separated from each other are displayed in one display pattern, a decline in resolution in stereoscopic display is preventable. 
       Second Embodiment 
       [0048]    Next, a stereoscopic display according to a second embodiment will be described below. In addition, like components are denoted by like numerals as of the stereoscopic display according to the first embodiment, and will not be further described. 
         [0049]      FIG. 9  illustrates a circuit responsible for display control in the stereoscopic display according to the embodiment. In the first embodiment, synchronization between the switching liquid crystal panel  1  and the liquid crystal display panel  2  is controlled. However, in the embodiment, the backlight control circuit  31  controls synchronization with ON/OFF operation of the backlight  3 . As the backlight  3 , a backlight of which ON/OFF states are switchable at high speed is used. For example, an LED (Light Emitting Diode) backlight is preferably used. In the embodiment, the timing controllers  21  and  22  and the backlight control circuit  31  correspond to specific examples of “a synchronization control section.” 
         [0050]    In the embodiment, synchronous control illustrated in parts A, B and C in  FIG. 10  is performed instead of synchronous control in the parts A and B in  FIG. 8 . In the synchronous control in the parts A and B in  FIG. 8 , synchronous control is performed with delay so that the switching timing of the barrier pattern is delayed as compared to the switching timing of the display pattern in the liquid crystal display panel  2 . Instead of this, in the embodiment, as illustrated in the part C in  FIG. 10 , synchronous control is performed with delay so that a turn-on timing of the backlight  3  is delayed as compared to the switching timing of the display pattern in the liquid crystal display panel  2 . Such control is performed so as to control ON/OFF operation of illumination for the whole screen of the liquid crystal display panel  2 . As illustrated in the parts A and B in  FIG. 10 , the timing of switching the display pattern in the liquid crystal display panel  2  and the timing of switching the barrier pattern in the switching liquid crystal panel  1  are synchronized. 
         [0051]    Also in the embodiment, the display pattern in the liquid crystal display panel  2  is switched in the same manner as that in the part A in  FIG. 8 . More specifically, in the first pixel position, the image for the viewpoint  1  starts to be displayed at the time t 10 , but the image starts to be displayed with full stability from the time t 11  which is behind the time t 10  by a predetermined period due to the response speed of liquid crystal. As illustrated in part C in  FIG. 10 , synchronous control is performed so that the backlight  3  turns on at the time t 11  at which the image is stably displayed. In the next period from the time t 30  to the time t 40 , in the first pixel position, the image for the viewpoint  2  starts to be displayed, but also in this case, synchronous control is performed so that the backlight  3  turns on at a time t 31  at which the image is stably displayed. At this time, in the first pixel position, the backlight  3  is controlled so as to turn off until stably changing (transiting) the displayed image from the image for the viewpoint  1  to the image for the viewpoint  2  (from the time t 20  to the time t 31 ). The backlight control circuit  31  controls such ON/OFF operation of the backlight  3  in response to a frame signal outputted from the parallax image data output section  23 . 
         [0052]    Also in the embodiment, the parallax images which are spatially and temporally separated are displayed on the two-dimensional display section so that stereoscopic display is achievable, so a decline in resolution in stereoscopic display is preventable. Moreover, the ON/OFF operation of the backlight  3  is controlled in synchronization with switching the display pattern, so the display image is shielded during a transition period in which the display pattern is switched in the liquid crystal display panel  2  so that the display image is not allowed to be viewed. Thereby, a stable stereoscopic image is allowed to be viewed. For example, a mixture of two parallax images is allowed to be prevented from being viewed during the transition period. 
       Third Embodiment 
       [0053]    Next, a stereoscopic display according to a third embodiment will be described below. In addition, like components are denoted by like numerals as of the stereoscopic displays according to the first and the second embodiments, and will not be further described. 
         [0054]    In the above-described embodiments, binocular stereoscopic display is described as an example, but the present embodiments are applicable to the case where multi-view stereoscopic display is performed. In the case of multi-view stereoscopic display, a number n of parallax images corresponding to n=3 or more viewpoints which are combined into a one-screen image while maintaining such a state that the parallax images are equally separated from each other are displayed. For example, in the case where stereoscopic display from three viewpoints is provided, three parallax images which are combined into a one-screen image while maintaining such a state that the parallax images which are spatially separated from each other are displayed. In this case, as a display pattern in which the parallax images are spatially separated, m kinds (m is an integer of 2≦m≦n) of patterns are used. The parallax images are displayed while periodically switching the m kinds of display patterns from one to another. As a barrier pattern, m different kinds of patterns are used corresponding to the display patterns, and the m kinds of barrier patterns are periodically switched from one to another. Synchronization between a switching operation of the display pattern and a switching operation of the barrier pattern is controlled as in the case of binocular stereoscopic display. Thereby, in the case of the multi-view stereoscopic display, the parallax images which are separated spatially by n, and temporally by m are displayed. 
         [0055]    The case of n=3 will be described as an example. On the liquid crystal display panel  2 , pixels displaying a first parallax image are defined as (R 1 , G 1 , B 1 ), and pixels displaying a second parallax image are defined as (R 2 , G 2 , B 2 ) and pixels displaying a third parallax image are defined as (R 3 , G 3 , B 3 ). 
         [0056]    For example, in the case of n=3 and m=2, when a display pattern of red pixels R 1 , R 2  and R 3  of the parallax images is used as an example, in a first display period T 1 , the pixels R 1 , R 2  and R 3  are displayed in this order, and in a second display period T 2 , for example, the pixels R 3 , R 1  and R 2  are displayed in this order. In the switching liquid crystal panel  1 , different barrier patterns are periodically switched from one to another in synchronization with switching these two display patterns so that stereoscopic display is achievable. Thereby, three parallax images which are separated spatially by three and temporally by two are displayed. 
         [0057]    Moreover, for example, in the case of n=3 and m=3, in a third display period T 3 , the pixels R 2 , R 3  and R 1  are displayed in this order. In the switching liquid crystal panel  1 , three different barrier patterns are periodically switched from one to another in synchronization with switching these three display patterns from one to another so that stereoscopic display is achievable. Thereby, three parallax images which are separated spatially by 3 and temporally by 3 are displayed. 
         [0058]    Thus, in the case of multi-view stereoscopic display, the parallax images which are spatially and temporally separated are displayed on the two-dimensional display section. Thereby, also in the case of multi-view stereoscopic display, compared to the case where parallax images which are spatially separated are displayed in one display pattern, a decline in resolution in stereoscopic display is preventable. 
         [0059]    In the above-described embodiments, the liquid crystal display panel  2  is used as a two-dimensional display section, but any other display panel may be used. For example, a self-luminous type display panel, for example, an organic EL (Electro-Luminescence) panel may be used. In the case where the other display panel is used, synchronous control to synchronize a switching timing of display pattern in the display panel and a switching timing of the barrier pattern may be appropriately adjusted according to a display response speed of the display panel and a switching response speed of the switching liquid crystal panel  1 . 
         [0060]    It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.