JP2008058346A - Animation display device and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique that makes flickers and animation visibility in animation display compatible. <P>SOLUTION: The animation display device is provided with a video display element which displays animation image, by alternately repeating the transition between a video display state and a non-video display state and is constituted, in such a manner that the time of the first transition that is the intermediate luminance state from the non-display state to the video display state is made longer than the time of the second transition that is the intermediate luminance, state from the video display state to the non-video display state. The video display state is a state in which the image is displayed according to input image data. The non-video display state is a display state, in which the image whose luminance is lower than in the video display state is displayed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a moving image display technique.

  The moving image display device includes a hold type display device in which an image is always displayed and an impulse type display device such as a CRT. While the hold-type display device has an advantage that there is no flicker (flickering feeling), it has a drawback that there is a problem of moving image visibility (moving image blur) caused by an afterimage of a display or a human eye. . On the other hand, the impulse-type display device has an advantage that the moving image visibility is good, but has a disadvantage that there is flicker (flickering feeling). Conventionally, considering both of these characteristics, the hold-type display device is mainly used for a PC monitor that displays a still image, and the impulse-type display device is mainly used for a television that displays a moving image.

  However, in recent years, with the widespread use of liquid crystal televisions and liquid crystal projectors, there is a demand for displaying moving images on a hold-type display device such as liquid crystal. In order to meet this demand, Patent Documents 1 to 3 propose techniques for performing impulse-type display by turning on and off a light source in a hold-type display device in order to suppress moving image blur.

JP-A-4-302289 JP-A-11-202285 JP 2000-122596 A

  However, such an impulse-type display has a problem in that the advantage of the hold-type display device that there is no flicker (flickering feeling) is lost.

  The present invention has been made to solve the above-described problems in the prior art, and an object of the present invention is to provide a technique for achieving both flicker and moving image visibility in moving image display.

The present invention provides a moving image display device, the moving image display device,
The moving image is displayed by alternately repeating the transition between the video display state and the non-display state, and the time of the first transition state that is an intermediate luminance state from the non-display state to the video display state Comprises a video display unit configured to be longer than the time of the second transition state, which is an intermediate luminance state from the video display state to the non-display state,
The video display state is a state in which an image is displayed according to input image data,
The non-display state is a display state in which an image having a lower luminance than the video display state is displayed.

  In the moving image display device of the present invention, the time of the first transition state, which is an intermediate luminance state from the non-display state to the video display state, is an intermediate luminance state from the video display state to the non-display state. Since it is configured to be longer than the time of the second transition state, it suppresses discomfort (flicker) caused by light adaptation performed unconsciously when the luminance from the non-display state to the video display state increases. In addition, moving image blur can be reduced. Moving image blur reduction is realized by eliminating afterimages on the human eye and afterimages on the display by sandwiching an image having a lower brightness than the image display state between each image display.

  Note that the configuration in which the time of the first transition state is longer than the time of the second transition state has a broad meaning including the case where the second transition state does not exist (that is, the time is zero). Have. Such a configuration can also be realized by using a display device in which the characteristic change from the non-display state to the video display state is gradual and the characteristic change from the video display state to the non-display state is relatively abrupt. It can also be realized by performing display control as described later.

In the moving image display device,
The video display unit includes a display device that displays the moving image, and a display control unit that controls the display device.
The display control unit may control the display device such that the first transition time is longer than the second transition time. In this way, the present invention can be applied to any display device having a sufficient reaction rate.

In the moving image display device,
The first transition state may be a display state in which an image in which the luminance of the image in the video display state is reduced at a uniform ratio is displayed. By so doing, it is possible to reduce the decrease in contrast while suppressing the suppression of flicker and moving image blur.

In the moving image display device,
According to the experiment of the present inventor, a remarkable effect can be obtained if the time of the first transition state is 2 ms or more or 1/8 or more of one frame period which is an image display update cycle. confirmed.

  The present invention relates to a moving image display apparatus, a moving image display apparatus control apparatus, a computer program and firmware for causing a computer to realize the functions of the method or apparatus, a recording medium storing the computer program, and the computer program. It can be realized in various forms such as a data signal embodied in a carrier wave, a consumable container provided with a storage device, and the like.

Next, embodiments of the present invention will be described in the following order based on examples.
A. Basic configuration of LCD projector:
B. Display processing in the comparative example of the present invention:
C. Display processing in the first embodiment of the present invention:
D. Display processing in the second embodiment of the present invention:
E. Display processing in the third embodiment of the present invention:
F. Variation:

A. Basic configuration of LCD projector:
FIG. 1 is a block diagram showing a configuration of a liquid crystal projector 10 as an embodiment of the present invention. The liquid crystal projector 10 includes an optical system 100 for projecting an image on a screen SC and a control system 200 for controlling projection light. The optical system 100 includes an illumination optical system 110, an LCD panel 120, and a projection optical system 130. The control system 200 includes a controller 210, an image processing unit 220, and an LCD driver 230.

  The controller 210 includes a CPU and a memory (not shown). The controller 210 controls the image processing unit 220 and the LCD driver 230. The image processing unit 220 processes an input image signal given from the outside and generates an input signal to the LCD driver 230. The processing of the input image signal includes various image processing such as image quality adjustment processing. The image quality adjustment processing includes processing such as brightness adjustment and color temperature correction.

  The LCD driver 230 generates a drive signal for driving the liquid crystal panel 120 based on the image data input from the image processing unit 220. This drive signal is supplied to the liquid crystal panel 120 and used to control the amount of transmitted light of each pixel included in the liquid crystal panel 120. The light transmitted through the liquid crystal panel 120 is irradiated to the projection optical system 130. The projection optical system 130 projects the light emitted from the liquid crystal panel 120 onto the screen SC.

  FIG. 2 is an explanatory diagram showing the internal configuration of the LCD panel 120 in the embodiment of the present invention. The LCD panel 120 includes a cell array 340 configured as a two-dimensional array of liquid crystal cells 342, a row drive circuit 125, and a column drive circuit 126. The cell array 340 can control each of the liquid crystal cells 342 by n word lines YV1 to YVn arranged in parallel in the horizontal direction and m data lines XH1 to XHm arranged in parallel in the vertical direction. It is configured. The potentials of the n word lines YV1 to YVn are controlled by the row driving circuit 125. The column drive circuit 126 controls the potentials of the m data lines XH1 to XHm.

  Each liquid crystal cell 342 is connected to a word line and a data line through a thin film transistor 343 in this embodiment. Each liquid crystal cell 342 corresponds to each display pixel (not shown) of the LCD panel 120 and controls its luminance.

  The LCD driver 230 supplies a video signal indicating the luminance state of each pixel and a horizontal synchronizing signal to the column driving circuit 126 and also supplies a vertical synchronizing signal to the row driving circuit 125 to display an image displayed on the LCD panel 120. To control. The column driving circuit 126 performs display control of each pixel in each scanning line based on the horizontal synchronization signal. The row driving circuit 125 performs display control of each scanning line based on the vertical synchronization signal.

  With such a configuration, video display is performed by sequentially displaying each scanning line constituting the video from the top to the bottom. The pixels constituting each scanning line are display-controlled in order from the left pixel to the right pixel.

B. Display processing in the comparative example of the present invention:
FIG. 3 is a time chart showing the display state of each scanning line in the comparative example. The frame in the figure indicates the frame period, and is a period corresponding to about 60 fps, for example. Each frame includes a non-display (black writing) state and a video display state. Such a non-display state is provided in order to suppress moving image blur in a hold-type display device such as a liquid crystal. The video display state is a video display state displayed according to the input video signal.

  FIG. 4 is an explanatory diagram illustrating a moving image display state in the comparative example. The moving image mp1 indicates a moving image recognized by the human visual system. The still images sp1 and sp2 indicate a state at a certain moment in the display device. The still images sp1 and sp2 have a black band (black writing). The black band portion indicates that the main scanning line constituting this portion is in a non-display (black writing) state in FIG. On the other hand, the portion where the image is displayed indicates that the main scanning line constituting this portion is in the image display state in FIG.

  The still image sp2 shows a display state after a predetermined time has elapsed from the moment when the still image sp1 is displayed. The black writing portion of the still image sp2 exists below the black writing portion of the still image sp1. This is because, as described above, each scanning line constituting the video is displayed (or scanned) in order from the top to the bottom. This black writing part is for erasing the afterimage remaining on the human eye or the display to suppress the motion blur.

  Thus, in the comparative example, the visibility of the moving image is improved by turning on and off the video display and performing the impulse type display in the hold type display device. However, in the comparative example, there is a problem in that the advantage of the hold-type display device that there is no flicker (flickering feeling) is lost by performing the impulse-type display. Conventionally, such a problem has been unavoidable as long as impulse-type display is performed.

  However, the inventor of the present application has investigated the problem of flicker (flickering) in the human visual system not from the viewpoint of display control of the display but from a physiological viewpoint. As a result of this investigation, the following useful literature was discovered. "Visual adaptation in relation to brief conditioning stimuli. Proceedings of the Royal Society of London, Series B, 128, 283-302, 1947, by B.H. Crawford."

  As a result of research in this document, it was found that the discomfort caused by flicker is not caused simply by fluctuations in light and darkness, but is caused by unconscious light adaptation and dark adaptation in the human visual system. . Furthermore, when comparing light adaptation and dark adaptation, it was found that light adaptation with a fast adaptation speed causes greater discomfort than dark adaptation with a slow adaptation speed. It was found that this light adaptation is performed unconsciously even when the flickering of the video is not perceptible, and places a greater burden on the visual system than dark adaptation. The inventor of the present application has created the following new technical idea based on such physiological knowledge.

C. Display processing in the first embodiment of the present invention:
FIG. 5 is a time chart showing the display state of each scanning line in the first embodiment of the present invention. The time chart of the first embodiment is different from the time chart of the comparative example (FIG. 3) in that it has a transition display (gray writing) state. The transition display state is a display state in which a gray display having a lower luminance than the video state and a higher luminance than the non-display state is performed.

  FIG. 6 is an explanatory diagram showing the display state of the moving image in the first embodiment of the present invention. The still images sp1a and sp2a have transition writing and black writing portions. Since the scanning is performed from the upper part toward the lower part, it is understood that the display state changes in the order of non-display (black writing), transition state (transition writing), and video display when attention is paid to each scanning line.

  The transition display state is an intermediate luminance state between the non-display state and the video display state, and gradually changes the luminance from the lowest luminance state of the non-display state to the luminance state of the video display state. There is an effect. It has been confirmed by the inventor that, by devising the change in the display state in this way, the stimulus to the human visual system related to light adaptation can be suppressed, thereby reducing the discomfort of flicker.

  In this way, in the first embodiment, flicker suppression and moving images are performed by performing transition display that performs gray display having a lower average luminance than the video state and a higher luminance than the non-display state before the video display state. Realization of both improved visibility. The transition display state may be an intermediate luminance state between the non-display state and the video display state, but it is preferable to change the luminance according to the change in the average luminance of the video display state. For example, the image display state may be configured to be about half the average luminance. In the experiment by the inventor of the present application, it was proved that flickering discomfort can be significantly reduced when the sum of the non-display state time and the transition display state time is 5 milliseconds or more.

  However, since “gray writing” is executed as the transition display, the inventor has also found that the contrast is slightly lowered by this intermediate display. However, the inventor has also created a means for solving this problem.

D. Display processing in the second embodiment of the present invention:
FIG. 7 is a time chart showing the display state of each scanning line in the second embodiment of the present invention. The time chart of the second embodiment differs from the time chart of the first embodiment in that the transition display state is not gray writing but a low-luminance video display state. The second embodiment was created by paying attention to the fact that the decrease in contrast in the first embodiment is caused by the use of a gray display having a uniform luminance regardless of the luminance distribution in the video.

  FIG. 8 is an explanatory diagram showing a display state of a moving image in the second embodiment of the present invention. The still images sp1b and sp2b differ from the still images sp1a and sp2a in that the transition writing portion is a low-luminance video display, and the other points are common.

  The low luminance video display state can be realized by displaying an image in which the luminance of the image in the video display state is reduced at a uniform ratio, for example, by setting the gradation value to half of the video display state. . However, in order to reduce the processing load, a plurality of pixels may be processed together. For example, a 9 × 9 pixel may be configured such that half of the gradation value at the center position is the gradation value of the 9 × 9 pixel.

  As described above, the second embodiment has an advantage in that a decrease in contrast can be suppressed by performing transition display, which is a low-luminance video display state, before the video display state. In the experiment by the inventor of the present application, it was proved that flickering discomfort can be significantly reduced when the sum of the non-display state time and the transition display state time is 5 milliseconds or more.

E. Display processing in the third embodiment of the present invention:
FIG. 9 is an explanatory diagram showing the configuration of a direct view liquid crystal display 140 (LCD display) in the third embodiment of the present invention. The direct-view liquid crystal display 140 controls a liquid crystal light valve 140L, four backlights 141 to 144 that project light to the liquid crystal light valve 140L, and the light amounts of these backlights 141 to 144. And a backlight drive circuit 140D. The backlight drive circuit 140D is connected to each of the four backlights 141 to 144 by four power supply lines BV1 to BV4.

  FIG. 10 is a time chart showing the light emission timing of each of the four backlights 141 to 144 from the first to the fourth. 1st BL has shown the light emission timing of the 1st backlight 141, and 2nd BL, 3rd BL, and 41st BL are light emission of 2nd backlight 142, 3rd backlight 143, and 4th backlight 144, respectively. It is timing. As shown in FIG. 10, the timing of each backlight is shifted because the video display is scanned from the upper scanning line to the lower scanning line.

  This configuration realizes the same image display as in the second embodiment by dimming the backlight divided into four with a predetermined timing shift in the direct-view liquid crystal display 140. As described above, the present invention can also be applied to the direct-view liquid crystal display 140.

F. Variation:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

F-1. In each of the above-described embodiments, an intermediate step state is provided to moderate the luminance change accompanying the change from the non-display state to the video display state. For example, as shown in the modification (FIG. 11). You may make it provide the transition state which changes a brightness | luminance change gently. In general, the present invention only needs to be provided with a transition state that is an intermediate luminance state from a non-display state to a video display state.

F-2. In each of the embodiments described above, the transition state is provided when the non-display state changes to the video display state. However, the transition state may be provided when the video display state changes to the non-display state. However, since the presence of the transition state leads to a decrease in video brightness, the transition state time at the transition from the non-display state where the stimulus to the visual system is noticeable to the video display state is changed from the video display state to the non-display state. It is preferable to make it longer than the transition state time at the time of change.

F-3. In each of the embodiments described above, the present invention is configured as the liquid crystal projector 10, but may be configured as a projector of another system such as a DLP (registered trademark) system or a three-tube system. Furthermore, in the above-described embodiments, the present invention is configured as a front projector, but can be applied to, for example, a rear projector. In addition, it can be applied to an impulse-type display device such as a plasma display.

F-4. In each of the embodiments described above, the transition display is realized by adjusting the amount of light transmitted through the LCD panel 120 or by dimming the backlight. For example, an additional LCD panel for limiting the projection light is provided. It may also be realized by mounting on the LCD panel 120 or the backlight.

F-5. In each of the embodiments described above, the transition state is set by the control of the display device. For example, the characteristic change from the non-display state to the video display state is gradual, and the characteristic change from the video display state to the non-display state is relatively low. This can also be realized by using a steep display device. For example, a change from black to white takes 2 to 12 milliseconds, and a change from white to black is a device of 2 milliseconds or less.

  When some or all of the functions of the present invention are realized by software, the software (computer program) can be provided in a form stored in a computer-readable recording medium. In the present invention, the “computer-readable recording medium” is not limited to a portable recording medium such as a flexible disk or a CD-ROM, but an internal storage device in a computer such as various RAMs and ROMs, a hard disk, and the like. An external storage device fixed to the computer is also included.

1 is a block diagram showing a configuration of a liquid crystal projector 10 as an embodiment of the present invention. Explanatory drawing which shows the internal structure of the LCD panel 120 in the Example of this invention. The time chart which shows the display state of each scanning line in a comparative example. Explanatory drawing which shows the display state of the moving image in a comparative example. 3 is a time chart showing the display state of each scanning line in the first embodiment of the present invention. Explanatory drawing which shows the display state of the moving image in 1st Example of this invention. The time chart which shows the display state of each scanning line in 2nd Example of this invention. Explanatory drawing which shows the display state of the moving image in 2nd Example of this invention. Explanatory drawing which shows the structure of the direct view type liquid crystal display in 3rd Example of this invention. The time chart which shows the light emission timing of the backlights 141-144. The time chart which shows the display state of each scanning line in the modification of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Liquid crystal projector 100 ... Optical system 110 ... Illumination optical system 120 ... Liquid crystal panel 340 ... Cell array 125 ... Row drive circuit 126 ... Column drive circuit 342 ... Liquid crystal cell 343 ... Thin film transistor 130 ... Projection optical system 140 ... Direct view type liquid crystal display 140D ... Backlight drive circuit 140L ... Liquid crystal light valve 141 ... First backlight 142 ... Second backlight 143 ... Third backlight 144 ... Fourth backlight 200 ... Control system 210 ... Controller 220 ... Image processor

Claims (6)

A moving image display device,
The moving image is displayed by alternately repeating the transition between the video display state and the non-display state, and the time of the first transition state that is an intermediate luminance state from the non-display state to the video display state Comprises a video display unit configured to be longer than the time of the second transition state, which is an intermediate luminance state from the video display state to the non-display state,
The video display state is a state in which an image is displayed according to input image data,
The moving image display device in which the non-display state is a display state in which an image having a lower luminance than the video display state is displayed. The moving image display device according to claim 1,
The video display unit includes a display device that displays the moving image, and a display control unit that controls the display device.
The display control unit is a moving image display apparatus that controls the display device such that the first transition time is longer than the second transition time. The moving image display device according to claim 1 or 2,
The moving image display apparatus is a display state in which the first transition state displays an image in which the luminance of the image in the video display state is reduced at a uniform ratio. The moving image display device according to any one of claims 1 to 3,
The moving image display device in which the time of the first transition state is 2 ms or more. The moving image display device according to any one of claims 1 to 4,
The moving image display device in which the time of the first transition state is one-eighth or more of one frame period which is an image display update cycle. A moving image display method,
A preparation step of preparing a display device for displaying a moving image;
A moving image display step of displaying a moving image on the display device by alternately repeating a transition between a video display state and a non-display state;
With
In the moving image display step, the time of the first transition state which is an intermediate luminance state from the non-display state to the video display state is an intermediate luminance state from the video display state to the non-display state. Including making the time longer than a time of a second transition state,
The video display state is a state in which an image is displayed according to input image data,
The moving image display method, wherein the non-display state is a display state in which an image having a lower luminance than the video display state is displayed.

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