JP5292026B2 - 3D image display apparatus and 3D image display method - Google Patents

Description

  The present invention relates to a three-dimensional image display apparatus and a three-dimensional image display method using multi-viewpoint images.

  As a three-dimensional image display device (naked eye type three-dimensional image display device) that can observe a three-dimensional image without glasses, a multi-view type, a dense multi-view type, an integral imaging method (II method), a one-dimensional II method (1D- II method: parallax information display only in the horizontal direction) is known. These have a common structure in which an exit pupil typified by a lens array is arranged on the front surface of a flat panel display (FPD) typified by a liquid crystal display (LCD). The exit pupils are provided at regular intervals, and a plurality of FPD pixels are assigned to one exit pupil. The exit pupil corresponds to a pixel of the three-dimensional image display device, and the pixel seen through the exit pupil is switched according to the observation position. That is, it behaves as a three-dimensional image display pixel whose pixel information changes depending on the observation position.

  The viewing area, resolution, and pop-out amount of the three-dimensional image displayed on the three-dimensional image display device have a trade-off relationship, and there is a problem of improving both the characteristics of the viewing area, resolution, and pop-out amount (Non-Patent Document 1). ).

Therefore, there is a method of improving the resolution per unit time by changing the number of light rays in a time-sharing manner using a shutter (Patent Document 1).
J. et al. Opt. Soc. Am. A vol. 15, p. 2059 (1998) Japanese Patent Application Laid-Open No. 07-92936

  However, even when the shutter is driven at, for example, 120 Hz and the number of light rays is changed, display disturbance occurs in which the shutter pattern is visually recognized. On the other hand, raising the shutter drive frequency further increases the technical difficulty, and also increases the difficulty in reducing power consumption and EMI.

  It is an object of the present invention to provide a three-dimensional image display apparatus and a three-dimensional image display method that reduce a display disturbance in which a shutter pattern is visually recognized.

  A three-dimensional image display device according to an aspect of the present invention is opposed to a planar image display unit in which pixels are arranged in a matrix in a first direction and a second direction orthogonal to the first direction, and the planar image display unit. The light ray control unit in which a plurality of exit pupils that control the light rays from the pixels are arranged, and the light ray that is arranged opposite to the surface opposite to the plane pixel display side of the light ray control unit and transmits the light ray And a control unit for controlling the transmittance of the shutter unit, and the control unit displays an image in one field on the planar image display unit. In this case, the transmittance of the shutter part in the other side region is lower than the first transmittance so that the transmittance of the shutter part in the one side region of the boundary between the exit pupils becomes the first transmittance. 2nd transmittance In other words, the shutter has a third transmittance that is lower than the first transmittance and higher than the second transmittance in the boundary region between the one side region and the other side region. It is characterized by controlling the part.

  The three-dimensional image display method according to one aspect of the present invention includes a planar image display unit in which pixels are arranged in a matrix in a first direction and a second direction orthogonal to the first direction, and the planar image display unit. A light beam control unit arranged opposite to each other and arranged with a plurality of exit pupils for controlling light beams from the pixels, and a surface opposite to the plane pixel display unit side of the light beam control unit are arranged and transmitted. A method of displaying a three-dimensional image on an image display device having a shutter unit for changing the light transmittance, and when displaying an image in one field on the planar image display unit, The transmittance of the shutter part in the one side region of the boundary between the exit pupils becomes the first transmittance, and the transmittance of the shutter part in the other side region is lower than the first transmittance. As before The shutter unit is controlled so that the transmittance of the shutter unit in the boundary region between the one side region and the other side region is lower than the first transmittance and higher than the second transmittance. It is characterized by doing.

  ADVANTAGE OF THE INVENTION According to this invention, the three-dimensional image display apparatus and the three-dimensional image display method which reduce the display disturbance which the pattern of a shutter is visually recognized can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 schematically shows the structure of the stereoscopic image display apparatus according to the first embodiment. The description will be made with the front side as viewed from the observer shown in FIG. In addition, directions such as up, down, left, and right in this description indicate relative directions from the position of the observer shown in FIG.

  The stereoscopic image display device includes a flat display device 101, a light beam control element 102, and an image switching device 103. The light beam control device 102 is provided on the display surface side of the flat display device 101. The image switching device 103 is provided on the opposite side of the light beam control device 102 from the flat display device 101 side. Accordingly, the light beam emitted from the display surface of the flat display device 101 passes through the light beam control device 102 and then enters the image switching device 103.

  In the flat display device 101, a set of sub-pixels (pixels) for emitting, for example, RGB three-color rays is arranged in an array on the display surface. Specifically, a display device having a liquid crystal display panel, an organic EL panel, a plasma panel, an SED panel, or the like can be used for the flat display device 101. In this embodiment, an example in which a liquid crystal display panel including a backlight light guide plate 1011 and a transmissive liquid crystal panel 1012 is used will be described.

  The light beam control device 102 is provided so that an observer can visually recognize a parallax image by periodically arranging light beam control elements having exit pupils for controlling the direction of light beams emitted from the flat display device 101. ing. A pinhole, a slit, or a lens can be used for the light beam control element. In this embodiment, an example in which the observer can visually recognize a one-dimensional parallax image in the left-right direction (column direction of the flat display device 101) in FIG. 1 will be described in order to simplify the description. In this case, the light beam control element can use a slit or a cylindrical lens extending in a substantially vertical direction (the row direction of the flat display device 101) with respect to FIG. The light beam control device 102 can be provided so that the direction in which the light beam control element extends and the row direction of the flat display device 101 have a predetermined angle.

  The image switching device 103 has a plurality of shutter portions arranged in an array. For example, a liquid crystal can be used for the shutter unit, and a transmissive liquid crystal panel can be used for the image switching device 103. The shutter unit can be arranged based on the arrangement of subpixels of the flat display device 101. For example, it arrange | positions so that the shutter part mentioned later may respond | correspond to one subpixel. That is, the subpixel size and the pitch between the shutter portions, more specifically, the pitch in the column direction and the row direction of the flat display device 101 can be arranged equally.

  In the stereoscopic image display device, when a video input signal input from the outside of the stereoscopic image display device is input, an input unit 104, a synchronization unit 105, and control units 106 and 107 are provided so that an observer can observe a stereoscopic image. Is provided. The input unit 104, the synchronization unit 105, and the control units 106 and 107 are provided for transmitting control signals to the flat display device 101 and the image switching device 103 based on the video input signal.

  The input unit 104 is provided with an input interface so that a video input signal can be input. For example, when a multi-parallax image such as a tile image is input to the input interface, the input unit generates drive data for driving the flat display device 101 based on the multi-parallax image. In addition to the generation of the driving data, switching data for driving the image switching device 103 is generated.

  The synchronization means 105 is provided to synchronize the generated drive data and switching data. Specifically, for example, the drive data generated by the input unit 104 is transmitted to the control unit 106, and the switching data is transmitted to the control unit 107 in a synchronized state based on a synchronization signal such as a clock signal.

  The control unit 106 transmits a control signal for controlling the flat display device 101 to the flat display device 101 based on the received drive data. In the case of the present embodiment, the synchronization unit 105 lights a backlight (not shown) provided in the vicinity of the backlight light guide plate 1011, and the control unit 106 controls the transmissive liquid crystal panel 1012.

  The control unit 107 transmits a control signal for controlling the image switching device 103 to the image switching device 103 based on the received switching data. In the case of the present embodiment, the control unit 106 controls a plurality of shutter units provided in the image switching device 103.

  The synchronization unit 105 generates switching data so as to synchronize with the vertical scanning signal of the first field from the vertical scanning signal of the first field among the control signals transmitted by the control unit 106. Here, N is a natural number. For example, when a frame image is displayed at 60 Hz, if N = 2, each field is displayed at 120 Hz. The switching data is generated, for example, so that the shutter unit switches between transmission and shading alternately in the odd-numbered field and the even-numbered field, and is generated to display the video displayed on the flat display device 101 in a time-division manner.

  FIG. 2 shows an example of a result of controlling the image switching device 103 based on the switching data. FIG. 2 shows a case where the front side of the drawing is the flat display device 101 side and the back side of the drawing is the image switching device 103 side.

  The light beam control device 102 shows an example in which a cylindrical lens is used as a light beam control element. Although the boundary with each cylindrical lens is also illustrated for convenience of explanation, a lens array in which a plurality of cylindrical lenses are integrally formed can be used for the light beam control device 102.

  The extending direction of the light beam control element is an oblique direction with a predetermined angle with respect to the row direction of the pixels 201. The pixel 201 includes, for example, three RGB subpixels 202. The shutter unit of the image switching device 103 is provided so that one shutter 203 corresponds to one subpixel.

  The switching data is generated so that the patterns shown in FIGS. 2A and 2B can be switched alternately. Specifically, the transmission shutter 203a and the light-shielding shutter 203c are generated so as to be switched alternately. In the vicinity of the boundary with each light beam control element (for example, a cylindrical lens), it is generated so as to be a semi-transparent shutter 203b of intermediate gradation. This intermediate gradation semi-transparent shutter 203b reduces display interference.

FIG. 2 shows an example in which the pattern shown in (a) is switched in the case of an odd field, and the pattern shown in (b) is switched in the case of an even field. For example,
Translucent shutter 203a → Shading shutter 203c
Shading shutter 203c → Translucent shutter 203b (near the boundary)
Light-shielding shutter 203c → Transmission shutter 203a (except near the boundary)
Translucent shutter 203b → light-shielding shutter 203c
Can be switched as follows.

  The switching data illustrated in FIG. 2 includes 18 subpixels as one, and a row direction like a checkerboard pattern in a set of a transmissive shutter 203a and a semi-transmissive shutter 203b and a set of a semi-transmissive shutter 203b and a light-shielded shutter 203c. And are alternately arranged in the column direction.

Here, p _sh shown in FIG. 2 is the pitch of the pair of the transmissive shutter 203a and the semi-transmissive shutter 203b and the pair of the semi-transmissive shutter 203b and the light-shielding shutter 203c in the column direction, and is an integral multiple of the sub-pixel width direction pitch. It is the pitch of the light beam control element (pinhole, slit, or cylindrical lens) of the light beam control device 102.

Further, p _sv shown in FIG. 2 is a pitch of a pair of the transmissive shutter 203a and the semi-transmissive shutter 203b and a pair of the semi-transmissive shutter 203b and the light-shielding shutter 203c in the row direction, and is an integral multiple of the sub-pixel height direction pitch. It is.

  In addition, the distance in the width direction between the translucent shutter 203b and the adjacent transmissive shutter 203a or the light-shielding shutter 203c is an integral multiple of the pitch in the width direction of the subpixels, and is a stereoscopic image displayed on the stereoscopic image display device that is defined in the observation area. Can be optimized based on the assumed viewing distance.

FIG. 3 shows an example of the width setting of the transmissive shutter unit 203a in consideration of the polarity of the shutter 203 for the purpose of preventing flicker of the image switching device 103. In order to prevent flicker, the width of the transmissive shutter 203a closer to the direction in which the light beam control element extends (p _{sv in} FIG. 3) is set such that the sum of the polarities of the opening 301 is close to zero. At this time, p _sv is an even multiple of the pitch in the column direction of the subpixels.

  As an example, a case where the liquid crystal display panel is driven by 2H2V when a liquid crystal display panel is used for the flat display device 101 will be described. The control unit 107 transmits a control signal so that the polarity is inverted every two rows in the row direction and every two columns (2H2V) in the column direction. Specifically, after the negative shutter 302 to which a negative voltage is applied continues for 2 rows and 2 columns, the positive shutter 303 to which a positive voltage is applied continues to 2 rows and 2 columns, and the control unit 107 performs control so that this is repeated. Send a signal.

Ideally, the control unit 107 transmits a control signal so that the minus shutter 302 and the plus shutter 303 are repeated in the opening 301 of the transmissive shutter 203a. As shown in FIG. 3, when p _sv is a width of two pixels, the polarity of the opening 301 is repeated every other pixel, and the sum of the polarities approaches zero.

  FIG. 4 shows an example of the timing of the control signal transmitted by the control unit 106 and the control unit 107.

  The control unit 107 controls the shutter unit so that transmission and light shielding are alternately switched between the odd-numbered field 406 and the even-numbered field 407 of the frame period. Specifically, an odd field control signal 401 for switching to the pattern transmitted to the odd field 406, for example, the pattern shown in FIG. 2A is transmitted from the start to the end of the odd field 406. Further, an even field control signal 402 for switching to the pattern transmitted in the even field 407, for example, the pattern shown in FIG. 2B is transmitted from the start to the end of the even field 407.

  On the other hand, the control unit 106 controls the flat display device 101 so that an image for each frame is displayed. At that time, black insertion is performed so that a video of a dark image (for example, a black image) is displayed between the frames for each frame period.

  Specifically, a black insertion control signal 403 for displaying a dark image is transmitted for a predetermined time including the timing at which the frame is switched. Image control data 404 for displaying a video corresponding to each frame is transmitted between the respective black insertion control signals 403. The predetermined time can be set to a black insertion time width 408 around the predetermined time, for example, with the timing at which the frame is switched.

  At this time, the synchronization means 105 is connected between the control unit 106 and the control unit 107 so that the odd field control signal 401 and the even field control signal 402 are switched while the control unit 106 transmits the black insertion control signal 403. Synchronize.

  If necessary, the synchronization unit 105 also controls the control unit 106 so that the light source (not shown) of the backlight light guide plate 1011 is turned off while the control unit 106 transmits the black insertion control signal 403. And the control part 107 and a light source are synchronized.

  In order to prevent flicker, the control unit 106 transmits an inversion drive signal 405 to invert the polarity of the signal applied to the flat display device 101 for each frame. In the example shown in FIG. 4, the inverted drive signal 405 is transmitted so that the odd field 406 has a positive pole and the even field 407 has a negative pole.

  In the stereoscopic image display apparatus thus formed, the control unit 107 is configured to transmit a control signal so that the vicinity of the boundary of the light beam control element becomes the semi-transmissive shutter 203b. Accordingly, the vicinity of the boundary of the light beam control element is not easily recognized by the observer, and display disturbance can be reduced.

  Further, the control unit 107 performs control so that a pair of the transmissive shutter 203a and the semi-transmissive shutter 203b and a pair of the semi-transmissive shutter 203b and the light-shielding shutter 203c are alternately arranged in the row direction and the column direction like a checkered pattern. It is configured to transmit a signal. Therefore, the transmission shutter 203a and the light-shielding shutter 203c of the light beam control element are alternately arranged in a wide range, so that display disturbance can be further reduced.

  In addition, since the video displayed in a time-sharing manner on the flat display device 101 is synchronized so that the odd field 406 and the even field 407 are switched at the black insertion timing, crosstalk can be reduced.

(Second Embodiment)
FIG. 5 shows an example of the result of controlling the image switching device 103 based on the switching data in the stereoscopic image display device according to the second embodiment. The difference from the stereoscopic image display apparatus according to the first embodiment is that the patterns of the transmissive shutter 203a and the light-shielding shutter 203c are alternately arranged in a checkered pattern as shown in FIG. On the other hand, the control unit 107 transmits a control signal to the image switching device 103 so as to be alternately arranged in a striped pattern.

  As in the first embodiment, the control unit 107 transmits a control signal to the image switching device 103 so that the vicinity of the boundary with each light beam control element is the semi-transmissive shutter 203b.

  As in the stereoscopic image display device according to the first embodiment, the stereoscopic image display device thus formed makes it difficult for the observer to recognize the vicinity of the boundary of the light control element, and reduces display disturbance. Can do. Further, crosstalk can be reduced.

(Modification)
FIG. 6 shows a modification of the stereoscopic image display apparatus according to the first embodiment. The difference from the stereoscopic image display device according to the first embodiment is that the direction in which the light beam control elements of the light beam control device 102 extend is parallel to the direction in which the pixels 201 are arranged. FIG. 6 illustrates an example in which the light beam control element extends in the row direction of the pixels 201.

As in the first embodiment, in order to prevent the image switching apparatus 103 from flickering, p _sv is set so that the sum of the polarities of the opening 301 portion of the shutter 203 approaches zero. At this time, p _sv is an odd multiple of the sub-pixel column pitch.

  As in the stereoscopic image display device according to the first embodiment, the stereoscopic image display device thus formed makes it difficult for the observer to recognize the vicinity of the boundary of the light control element, and reduces display disturbance. Can do. Further, crosstalk can be reduced.

  FIG. 7 shows a modification of the stereoscopic image display apparatus according to the second embodiment. The difference from the stereoscopic image display device according to the second embodiment is that the direction in which the light beam control elements of the light beam control device 102 extend is parallel to the direction in which the pixels 201 are arranged. FIG. 2 illustrates an example in which the light beam control element extends in the row direction of the pixels 201.

  The stereoscopic image display device thus made is less likely to be recognized by the observer near the boundary of the light beam control element, as in the stereoscopic image display device according to the second embodiment, thereby reducing display disturbance. Can do. Further, crosstalk can be reduced.

3D display device according to first embodiment of the present invention An example of a result of controlling the stereoscopic display device according to the first embodiment of the present invention An example of the polarity of the image switching device of the stereoscopic display device according to the first embodiment of the present invention An example of a control signal of the stereoscopic display device according to the first embodiment of the present invention 3D display device according to second embodiment of the present invention Modification of stereoscopic image display device according to first embodiment Modification of stereoscopic image display device according to second embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Flat display device 102 Light beam control element 103 Image switching apparatus 1011 Backlight light-guide plate 1012 Transmission-type liquid crystal panel 104 Input part 105 Synchronization means 106, 107 Control part 201 Pixel 202 Subpixel 203 Shutter 203a Transmission shutter 203b Semi-transmission shutter 203c Light-shielding shutter 301 opening 302 minus shutter 303 plus shutter 401 odd field control signal 402 even field control signal 403 black insertion control signal 404 image control data 405 inversion drive signal 406 odd field 407 even field 408 black insertion time width

Claims (7)

A planar image display unit in which pixels having a plurality of subpixels are arranged in a matrix in a first direction and a second direction orthogonal to the first direction;
Light control in which a plurality of exit pupils arranged in a third direction intersecting the first direction and the second direction are arranged so as to be opposed to the planar image display unit and control the direction of light from the pixels. And
A shutter unit that is disposed opposite to the surface opposite to the plane pixel display unit side of the light beam control unit, and that can control the transmittance of the transmitted light beam for each region,
When the transmittance of the shutter unit is displayed on the planar image display unit in one field, the transmittance of the shutter unit in the one side region of the boundary between the exit pupils is defined as the first transmittance. The shutter unit in the boundary region between the one side region and the other side region so that the transmittance of the shutter unit in the other side region is a second transmittance lower than the first transmittance. A first control unit that controls the transmittance so that the third transmittance is lower than the first transmittance and higher than the second transmittance;
A second control unit that controls the polarity of a signal applied to each of the sub-pixels of the planar image display unit;
Have
The first control unit adjusts the transmittance of the shutter unit so that the sum of the polarities applied to the sub-pixels through which light is transmitted with the first transmittance by the shutter unit is the same as positive and negative. 3D image display device to be controlled. The pixel has subpixels for emitting light beams of at least three different wavelengths in the first direction, and is an integer between the pitch of the boundary region in the first direction and the pitch of the subpixel in the first direction. The three-dimensional image display device according to claim 1, wherein doubles coincide with each other. The first control unit has a first length in the first direction of the one side region that is shorter than a second length in the first direction of the other region, and a third length in the first direction of the boundary region. The three-dimensional image display device according to claim 1, wherein the transmittance of the shutter unit is controlled to be shorter than the second length and the first length . When the first control unit displays an image in a field next to the one field,
In order that the transmittance of the shutter portion in the one side region becomes the second transmittance,
The transmittance of the shutter portion in the other side region is the first transmittance,
The transmittance of the shutter portion in the boundary region is the third transmittance,
The three-dimensional image display device according to claim 1, wherein the shutter unit is controlled. The first control unit includes a set of the shutter unit serving as the first transmittance and the shutter unit serving as the third transmittance, and the shutter unit serving as the second transmittance and the third transmittance. 4. The shutter unit according to claim 1, wherein the shutter unit is controlled so that a set of the shutter unit and the second unit are alternately arranged in the first direction and the third direction. The three-dimensional image display apparatus described in 1. The first control unit changes the transmittance of the shutter unit while a dark image displayed between the one field and the next field is displayed on the planar image display unit. The three-dimensional image display device according to claim 4, characterized in that: A planar image display unit in which pixels having a plurality of sub-pixels are arranged in a matrix in a first direction and a second direction orthogonal to the first direction, and disposed opposite to the planar image display unit. A light beam control unit in which a plurality of exit pupils extending in a third direction that intersects the first direction and the second direction are controlled, and the plane pixel display side of the light beam control unit is opposite to the light beam control unit. A method of displaying a three-dimensional image on an image display device having a shutter unit that is disposed opposite to the surface of the screen and capable of controlling the transmittance of the transmitted light for each region,
  When the transmittance of the shutter unit is displayed on the planar image display unit in one field, the transmittance of the shutter unit in the one side region of the boundary between the exit pupils is defined as the first transmittance. The shutter unit in the boundary region between the one side region and the other side region so that the transmittance of the shutter unit in the other side region is a second transmittance lower than the first transmittance. Is controlled to be a third transmittance lower than the first transmittance and higher than the second transmittance, and is applied to the sub-pixel through which light is transmitted at the first transmittance by the shutter unit. The sum of the polarities to be the same number between plus and minus,
  Controlling the polarity of a signal applied to each of the sub-pixels of the planar image display unit;
3D image display method characterized by the above.

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