JP2007065621A - Apparatus and method for video display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for video display that make it possible to display an invariably stable moving picture, by writing image data in synchronism with blinking display of a display means, even when the writing timing of the image data to a display means (more specifically, a display panel) and blinking display timing of the display means shift from each other. <P>SOLUTION: A plurality of different still pictures A, B, and C stored in an image memory are read out, immediately after the blinking display (points t3 and t6 of time in Fig. 7), based on blinking display pulses PL for light emission, supplied to a display means in synchronism with the blinking display pulses PL, when the plurality of different still images A, B, and C are displayed by the same display means in sequence by blinking at specified intervals. Simultaneously, image data of the still images A, B, and C are written to the display means (Figs.7C to 7F). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a video display device and a video display method in which a moving passenger who travels and moves with a person such as a train traveling on a rail can view continuous motion images (moving images).

  Specifically, a plurality of different still images are prepared, and the plurality of still image data are sequentially selected one by one and written on a display panel (for example, a flat display panel) constituting the display means, and supplied to the display panel. By writing still image data in synchronization with the flashing display pulse for light emission, even if the timing of the flashing display pulse and the timing of writing the still image data to the display panel become asynchronous, multiple different moving images can be displayed. It is designed to provide stable and simultaneous services.

  Conventionally, for example, a still image displayed on the wall surface of the tunnel is seen as a moving image by flashing and displaying still images divided into a plurality of frames so that they can be seen from the train window along the train track that has entered the tunnel. An image display device that can be used has been proposed (see, for example, Patent Document 1).

  In this case, as shown in FIG. 16, the video display device 1 is configured by a plurality of display means 6 arranged on the wall surface 5 a in the tunnel 5 at a predetermined interval. When the still image of each frame composing the moving image is displayed blinking on each display means 6, the passenger in the train 4 moving at a predetermined speed can visually recognize the frame-advanced video as a moving image from the vehicle window 4a. Even a still image can be provided with a moving image similar to a television image.

  In order for humans to see continuous still images as moving images, 24 frames per second in the case of movies, 30 frames per second in the NTSC standard, and PAL standard in the case of television In that case, 25 frames are required per second. Therefore, a minimum of 24 frames / second is required to obtain a normal moving image.

  For example, the installation interval of the display means 6 (for example, a flat display panel such as a liquid crystal display panel) for displaying a still image of 30 frames / second differs depending on the traveling speed of the train 4. For example, when the speed is 40 km / h, the installation interval is 37 cm. When the speed is 60 km / h, the installation interval is 53 cm.

  The flashing display timing on the display means 6 is controlled according to the traveling speed of the train 4 so that a stable natural moving image can be provided to the passenger even if the traveling speed of the train 4 changes. A moving body display device and method capable of performing stable image display according to the speed of the moving body are already known (see, for example, Patent Document 2).

  The moving image based on the still image provided to the passenger is the same for all the passengers of the train 4 of the same organization. For example, when a 4-second moving image (for example, moving image A) is provided by a still image composed of 30 frames per second, as shown in FIG. (6a, 6b, 6c,..., 6n: n = 120) are arranged, and still images of the corresponding frame #i (i = 1 to 120) are obtained so that a moving image is completed for 4 seconds. It is supplied intermittently. In FIG. 17 and subsequent figures, since a liquid crystal display panel is used as the display means 6, the display means 6 is illustrated as “LCD terminal #”.

Japanese Unexamined Patent Publication No. 2000-172220 (pages 3, 4 and 1) JP-A-11-202818 (pages 3, 4 and 1)

  Since the type (content) of the moving image that can be provided to the passenger is not fixed to one type, the image content can be arbitrarily changed. For example, a plurality of image sources (video sources) are prepared so that a moving image is switched for each train organization so that a moving image to be provided varies depending on a passing time, or a moving image can be switched depending on a time zone. An image source may be appropriately selected and supplied. However, in this case, all the passengers in the same organization will see the same moving image.

  Here, as shown in FIG. 17, when the passenger A is used as a reference, the same still image appears to be displayed. However, in actuality, an image of the front facing the passenger A, for example, the frame # 4 is displayed. When the still image A is used as a reference, the still image A one frame before (still image A of frame # 3) is displayed on the left display means (planar display panel) 6c, and 1 on the right display means 6e. Since the still image A (future) of the frame ahead (still image A of frame # 5) is displayed, the still images A of the preceding and following frames can be seen at the same time.

  Therefore, if separate images can be displayed on the adjacent display means 6 other than the front face in the passenger's field of view, a plurality of moving images can be provided to the passenger in such an image that a plurality of television images enter the field of view. Conversely, a moving image different from that of the passenger A can be provided to the passenger adjacent to the passenger A.

  An example of displaying three different still images will be described with reference to FIG. FIG. 18 shows an example of a certain display timing (flashing display timing). The still image B corresponding to frame # 4 is displayed on the display means 6d facing the passenger A, and the frame is displayed on the display means 6c adjacent to the left. If the still image C corresponding to # 3 is displayed and the still image A corresponding to the frame # 5 can be displayed on the display means 6e on the right side, the passenger A can enjoy three different still images at the same time. If attention is paid to a passenger adjacent to the passenger A, a still image different from that of the passenger A can be enjoyed.

  Therefore, in the case of three different still images, the still image switching state from the train approach side is shown in FIG. At the first blinking display timing (light emission timing) t = 0, the still image A (frame # 1) is displayed on the display means 6a, and this still image A can be seen by the passenger A (FIG. 19A).

  At the next blinking display timing t = Δt, as shown in FIG. 19B, the still image A (frame # 2) is displayed on the second display means 6b, and the passenger A can continue to see this still image A. . At the same time, the still image B (frame # 1) is displayed on the first display means 6a. For example, the passenger B adjacent to the passenger A can see the still image B. This still image B can be seen through the passenger A.

  At the next blinking display timing t = 2Δt, as shown in FIG. 19C, the still image A (frame # 3) is displayed on the third display means 6c, and the passenger A can continue to view the still image A. . At the same time, the still image B (frame # 2) is displayed on the second display means 6b. The passenger A can see the still image B as well as the passenger B adjacent to the passenger A. And since the still image C (frame # 1) is displayed on the 1st display means 6a, the passenger C adjacent to the passenger B can see this still image C. Passenger B can see the still images C and A that move forward and backward.

  At the next blinking display timing t = 3Δt, the display positions and frame addresses of the still images A, B, and C are sequentially shifted one by one, and the still image A (frame #) is displayed on the first display means 6a. 1) is displayed. By sequentially displaying still images while switching in this way, a plurality of different moving images can be simultaneously provided to persons on the same train. The same applies after t = 4Δt (FIG. 19D).

  By the way, in the case of a television image as described above, a still image of 30 frames per second is required. Ideally, the rewrite timing of the image data from the image memory to the display means 6 and the blinking display timing of the display means 6 are synchronized with the vertical synchronization signal VP under a certain traveling speed. For example, when the traveling speed is 60 km / h, the rewriting timing and the blinking display timing can be designed to be synchronized with the vertical synchronization signal VP.

  However, since the traveling speed of the train 4 is not always constant, the rewriting timing and the blinking display timing are different at this time. Therefore, these timings are shifted without being synchronized.

  Since a plurality of different still images are displayed while being sequentially switched on the same display means 6, when the blinking display timing gradually shifts with respect to the rewriting timing, the immediately previous blinking display is displayed. When the image data of a still image is overwritten with the image data of a new still image to be blinked, the next blinking display timing may arrive.

  This is because, when a flat display panel such as a liquid crystal display panel or a plasma display panel is used as the display panel of the display means 6, as is well known, image data is always rewritten repeatedly for each pixel (pixel). This is because (refresh processing) is required.

  In this way, when image data of different still images is written in the same display means 6, if a blinking display pulse is supplied, an unstable still image is displayed. This is because, in order to project the rewritten image information, at least a reaction time called a response time is required until the image information is displayed after being rewritten. As described above, when image data of two still images coexist as image information of the same display means 6, the latest written image data is unstable because the elapsed time after writing is less than the reaction time. Therefore, stable image display cannot be expected.

  In view of this, the present invention allows image data to be synchronized with the blinking display on the display means even when the writing timing of the image data to the display means (specifically, the display panel) and the blinking display timing on the display means are different. The present invention provides a video display device and a video display method that can always display a stable moving image by writing.

According to a first aspect of the present invention, there is provided a video display device according to the present invention, wherein a still image supplied to a plurality of display means arranged at a predetermined interval along a path of a moving body is blinked and displayed. In a video display device that provides a typical video,
A plurality of display means having a display panel arranged in a site that can be seen from the mobile body by a passenger of the mobile body;
Speed detecting means for detecting the traveling speed of the moving body;
Based on the traveling speed of the moving body obtained from the speed detection means, a control unit that generates a flashing display pulse for light emission supplied to the display means,
In order to sequentially display still images on a display panel provided for each of the display means, an image memory for storing a plurality of different still image data, and a light emission driving unit for the display panel to which the blinking display pulse is supplied It consists of a display control unit,
The display control unit performs writing control in which the plurality of still images are sequentially selected one by one and still image data is written on the display panel.

According to a seventh aspect of the present invention, there is provided a video display method according to the present invention, wherein the still image data supplied to a plurality of display means arranged at a predetermined interval along the path of the moving body is blinked to display the still image. A video display method for providing continuous video by:
A first step of sequentially displaying a plurality of different still images blinking at predetermined intervals on the same display means;
The second step of writing image data of the still image to the display unit in synchronization with the flashing display pulse for light emission supplied to the display unit.

  The present invention has memory means (image memory) that stores a plurality of different still image data so that a plurality of different still images can be displayed blinking. This image memory is provided for each display means (specifically, a display panel). For example, when the m-th display means counting from the beginning displays the m-th frame still image, a plurality of still images corresponding to the m-th frame are stored in the image memory. Has been. For example, when three still images A, B, and C are sequentially switched and displayed, they are read out in the order of still image B → still image C → still image A, for example, and blinked sequentially.

  In the (m−1) th display means, each image data of the still images A, B, and C of the (m−1) th frame is stored in the corresponding image memory, and according to the above example, a still image C → Still image A → Still image B are read in this order, and blinked in that order.

  Similarly, in the (m + 1) th display means, each image data of the still images A, B, and C of the (m + 1) th frame is stored in the corresponding image memory, and the still image A → the still image B → the still image. The data are read in the order of C and blinked in that order.

  For convenience of explanation, if it is assumed that the passenger does not move, at a flashing display timing, when the still image B is displayed on the display means facing the passenger, the still image C is displayed on the left display means. The still image A is displayed on the right display means. At the next blinking display timing, the still image C is displayed on the display means facing the passenger, the still image A is displayed on the left display means, and the still image B is displayed on the right display means. The At the next blinking display timing, still image A is displayed on the display means facing the passenger, still image B is displayed on the left display means, and still image C is displayed on the right display means. The Accordingly, if attention is paid to the same display means, still images are sequentially switched and displayed in the order of A → B → C → A → B →.

  The writing of the image data to the display means is synchronized with the blinking display timing. In particular, image data is written immediately after blinking display. This is to prevent display of a still image from becoming unstable and to realize blinking display in consideration of a reaction time peculiar to a flat display panel such as a liquid crystal display panel as display means.

  Immediately after the light emission pulse is turned on, image data to be read out next is read out, and the image data is sequentially written into the liquid crystal display panel. Until the next blinking display is performed, the same image data is sequentially rewritten while being read. Until the next blinking display is performed in this manner, the already written image data of the previous frame is only overwritten, so the blinking display timing is set before the rewriting of the image data for one frame is completed. Even if it arrives, both the image data before rewriting and the image data after rewriting are none other than image data of the same frame. That is, different image data is written in the same liquid crystal display panel and is not blinked in that state.

  Further, since the image data written immediately before the blinking display timing is the same as the image data written one frame before, the reaction time required until the next image display is sufficiently secured. Yes.

  In other words, in the present invention, a plurality of different still images are sequentially blinked and displayed on the same display means at predetermined intervals, and the blinking is performed in synchronization with the flashing display pulses for light emission supplied to the display means. The image data of the still image is written into the display means immediately after the blinking display by the display pulse. By performing such blinking display control, it is possible to avoid unstable image display and realize stable moving image display.

  In this invention, it has a some display means arranged in the site | part which the passenger of a moving body can see from a moving body. The display means (display device) includes a flat display panel such as a liquid crystal display panel and a light emitting device thereof. The flat display panel may be a strip-shaped flat display panel in addition to a two-dimensional flat display panel capable of displaying a full-size still image.

  When using a strip-shaped display panel, a full-size still image is divided and displayed, and among the full-size still image data, still image data matching the display size of the display panel is sequentially supplied, By sequentially displaying a part of still images of a plurality of sizes, a full size still image is displayed within the display period of one blinking display pulse.

  For example, when a display panel is composed of m pixels in the horizontal direction and n pixels in the vertical direction, and a strip-shaped flat display panel having the number of (1 / m, n) pixels is used, it corresponds to one screen. All of the still image data is sequentially divided and displayed every 1 / m within the display period of one blinking display pulse.

  A light emitting diode (LED) is used for such a strip-shaped flat display panel. By using a self-luminous display element in this way, a very inexpensive flat display panel can be used.

  It has speed detecting means for detecting the traveling speed of the moving body, and based on the traveling speed of the moving body obtained from the speed detecting means, a flashing display pulse (light emitting pulse) for light emission supplied to the display means is generated. A control unit. A flashing display pulse having a flashing display period corresponding to the traveling speed is obtained by this control unit.

  A display control unit for the display means; The display control unit includes an image memory that is a memory unit that stores a plurality of different still images as described above, a light emission driving unit to which a blinking display pulse is supplied, and images for a plurality of still image data. And a memory selection unit.

  The light emission driver is for driving a light emitting device associated with the liquid crystal display panel. In the image memory selection unit, write control is performed such that a plurality of still images are sequentially selected one by one in a state synchronized with the blinking display pulse and the image data is written on the display panel. Further, in the image memory selection unit, in synchronization with the blinking display pulse, writing control is performed so that image data is written to the display means immediately after the blinking display by the blinking display pulse. When a light emitting diode is used as the display panel, this light emission driving unit can be omitted.

  The present invention sequentially blinks a plurality of different still images on the same display means at predetermined intervals, and blinks in accordance with the blinking display pulses for light emission supplied to the display means. The image data of the still image is written to the display means immediately after the display.

  According to this, even if the timing for reading out the image data of the still image and the blinking display timing for the display means become asynchronous, unstable image display can be avoided. Therefore, stable moving image display can be realized even when moving images are displayed using a plurality of different still images.

  Hereinafter, a video display device and a video display method according to embodiments of the present invention will be described with reference to the drawings.

  Also in the present invention, as described in the conventional example, along the traveling direction (traveling direction) in which the moving body, for example, the train travels, the wall surface in the tunnel facing the passenger is arranged with a predetermined interval. A plurality of display means (display devices) and a control system for supplying image data for a desired still image to the plurality of display means constitute a video display device.

  FIG. 1 shows a schematic configuration of a video display apparatus 100 according to the present invention. The video display device 100 includes a display device 11 as a display unit, a control unit 12 as a control unit, and a speed detection unit 13 as a speed detection unit.

  As the display device 11, a full-size two-dimensional display panel capable of simultaneously displaying one screen, for example, a flat display panel such as a liquid crystal display panel can be used.

  FIG. 1 illustrates a liquid crystal display panel (LCD (Liquid Crystal Display) terminal device). A plurality of liquid crystal display devices 11 (11a, 11b, 11c,... 11n) are arranged along the traveling path of the train 4 while maintaining a predetermined interval as in the prior art.

  The liquid crystal display device 11 includes a display panel 20, a light emitting device 30, and a display control unit 40 as shown in FIG. The display panel 20 may be a reflective type or a transmissive type. In this example, the display panel is a transmissive LCD having a display screen of about 20 inches. Therefore, the light emitting device 30 functions as a so-called backlight, and a flashlight (strobe light), a white LED, or the like is used. By turning on the light emitting device 30 instantaneously, the image information supplied (written) to the display panel 20 can be displayed as a still image. The light emitting device 30 is controlled to blink (strobe control) in order to reproduce a moving image using a frame-by-frame still image.

  When a flashlight is used for the light emitting device 30, a flashlight driving circuit (described later) as the light emission driving unit 50 operates in response to a blinking display pulse PL for blinking control represented by a predetermined duty ratio. .

  The display panel 20 and the light emitting device 30 are controlled based on the display control unit 40. The display control unit 40 has an image memory 42 as memory means for storing image data of a plurality of different still images. In this example, since three different still images A, B, and C are displayed as moving images, first to third image data memories 42A to 42C are prepared. The number of still images that can be selected is not limited to the above example, and in principle, the moving images can be switched and displayed up to the number of still images (30 frames per second) for the number of installed liquid crystal display panels. Is possible. As the image memory 42, a nonvolatile semiconductor memory having a large capacity, a hard disk device, or the like is suitable. In this example, a semiconductor memory is used.

  A communication control unit 44 is provided for storing still image data in the image memory 42. The communication control unit 44 is provided to communicate with the adjacent liquid crystal display device 11 and the control unit 12 to synchronize the entire system. Information is also exchanged from the control unit 12 described later.

  Of the image data transferred from the control unit 12 side, the image data (Ai, Bi, Ci) of the corresponding frame number (#i) is stored in the image memory 42 via the communication control unit 44. By providing the communication control unit 44, the image data can be updated or changed. This is because it is preferable that the image data can be changed depending on the time zone.

  Among various information received by the communication control unit 44, various timing signals are supplied to the LCD driving unit 46. Here, the timing signal is a generic name for a clock signal CK for reading and writing image data, and a synchronization signal such as a horizontal drive signal HS (H) and a vertical drive signal VP (V).

  The timing signal output from the LCD driving unit 46 is supplied as a signal for driving the display panel 20. The communication control unit 44 receives the blinking display pulse PL transferred from the control unit 12. The received blinking display pulse PL is supplied to the light emitting device 30 via the light emission drive unit 50, and the light emitting device 30 is controlled to blink at the reception timing of the blinking display pulse PL.

  The timing signal output from the LCD drive unit 46 is also supplied to the image memory selection unit 48. The image memory selection unit 48 is a control circuit for the image memory 42, and is further supplied with a blinking display pulse PL separated by the communication control unit 44 and a memory select signal MSa.

  The image memory selection unit 48 performs control for determining which image data memory in the image memory 42 is to be accessed. By designating the memory select signal MS (MSa in the figure) and the address bus for the image memory 42, any one of the first to third image data memories 42A to 42C is sequentially designated and designated. The image data stored in the memory is read in frame units in synchronization with the clock signal CK.

  Which image data memory is selected first is determined in advance by the order of the arranged liquid crystal display panels and the number of still images to be displayed (three in the embodiment). A case where a memory select signal MSa for selecting the image data memory 42A is transmitted from the control unit 12 is shown.

  Of course, instead of using the memory select signal MSa generated by the control unit 12, the image memory selection unit 48 itself may generate the memory select signal MSa using, for example, a trigger signal from the control unit 12. .

  Reading of image data from the image memory 42 is performed in synchronization with the blinking display pulse PL. In this example, reading of image data starts immediately after the blinking display (immediately after the strobe light is emitted). This is to prevent unstable moving image display even when the blinking display pulse PL is not synchronized with the vertical synchronization signal VP. Details thereof will be described later.

  When the blinking display pulse PL arrives, the image data memory to be read next is switched. That is, until the blinking display pulse PL arrives, the same image data memory is accessed and the image data is continuously read.

  Note that the number of frames for the same still image stored in the image memory 42 varies depending on the traveling speed of the train 4. This is because when the speed is low, the number of frames to be displayed on one liquid crystal display device 11 increases, so that the number of frames that must be stored in the image memory 42 must also be increased.

  FIG. 3 shows an example of the control unit 12. In addition to functioning as a still image supply source, the control unit 12 detects the speed of the train 4 detected by the speed detection unit 13, and generates a blinking display pulse PL having a cycle corresponding to the traveling speed. It is provided for.

  The speed detection unit 13 includes a detection sensor 13 a that detects the entry of the train 4 and a speed detection sensor 13 b that detects the traveling speed of the train 4. The detection sensor 13a detects that the train 4 has entered a predetermined section, for example, a section in which the video display device 100 (specifically, the liquid crystal display device 11a) is installed, and then one component of the train 4 has completely passed. Only on during A detection signal from the detection sensor 13 a and a signal related to the speed of the train 4 detected by the speed detection sensor 13 b are input to the control unit 12.

  The control part 12 can be normally comprised with a personal computer. FIG. 3 is a configuration example of the control unit 12 when a personal computer is used. As is well known, the control unit 12 includes a central processing unit (CPU) 60, a RAM 62 that functions as storage means for storing still image data, a ROM 64 that is a memory storing a control program, a buffer memory 66, In this example, which is an external input device, it includes a mouse 68, a keyboard 70 for inputting control information, and the like.

  The CPU 60 controls the overall operation of the video display device 100 while using the RAM 62 as a work area in accordance with a control program stored in the ROM 64. The CPU 60 further has a function of calculating the cycle of the flashing display pulse PL based on the traveling speed of the train 4 detected by the speed detection sensor 13b and generating the flashing display panel PL corresponding to the cycle.

  The CPU 60 has a function of selecting a still image from the image input device 76 and storing it in the RAM 62. From the stored images, the CPU 60 selects three still images A, B, and C to be actually provided as display means. Delivered to a functioning liquid crystal display device 11. A plurality of still images to be distributed can be prepared in advance as distribution programs. In this case, the necessary still images are selected by displaying the distribution program on the display unit 74.

  Since the detection sensor 13a is installed at a position closest to the first liquid crystal display device 11a installed on the train entry side, the entry of the train 4 can be detected by the detection sensor 13a. A signal from the detection sensor 13a when the passage of the train 4 is detected is supplied to the CPU 60.

  In the present invention, when a plurality of different still images are sequentially switched and displayed on the same liquid crystal display device 11 in a flashing manner, the flashing display pulse is synchronized with the flashing display pulse PL for light emission supplied to the liquid crystal display panel 20. Immediately after blinking display by PL, writing of still image data to the liquid crystal display panel 20 is sequentially performed at each blinking display timing. Accordingly, three different still images can be sequentially switched and displayed in a toggle manner in synchronization with the blinking display pulse PL. This switching display process is repeated until the train 4 for one train passes completely.

  Since the display order can be arbitrarily set, for example, as shown in FIG. 4, the still images are sequentially switched in the order of A → B → C → A →... In synchronization with the blinking display pulse PL (described later). It shall be displayed. For convenience of explanation, description will be made using the third to fifth liquid crystal display panels 20c to 20e as shown in FIG.

  When the third liquid crystal display panel 20c displays a still image of the third frame (third frame), the first image memory 42A stores the third frame (frame # 3). The corresponding first still image (image data) A3 is stored, the second still image B3 corresponding to the third frame is stored in the second image memory 42B, and the third still image is stored in the third image memory 42C. A third still image C3 corresponding to the frame is accumulated.

  Therefore, in the fourth liquid crystal display panel 20d, the first still image A4 corresponding to the fourth frame (frame # 4) is stored in the first image memory 42A, and the second image memory 42B. 2 stores a second still image B4 corresponding to the fourth frame, and stores a third still image C4 corresponding to the fourth frame in the third image memory 42C.

  Similarly, the first still image A5 corresponding to the fifth frame (frame # 5) is stored in the first image memory 42A provided in the fifth liquid crystal display panel 20e, and the second image memory The second still image B5 corresponding to the fifth frame is stored in 42B, and the third still image C5 corresponding to the fifth frame is stored in the third image memory 42C.

  When the still image A (A5) blinks on the liquid crystal display panel 20e, the still image B (B4) blinks on the adjacent liquid crystal display panel 20d one frame before, and the liquid crystal display panel two frames before In 20c, the still image C (C3) is displayed blinking. As a result, the passenger A can see three different moving images at the same time. In other words, by the time the train 4 enters and passes through the video display device 100, the passenger A can see three different moving images depending on the facing display means.

  The reading of the image data from the image memory 42 and the writing of the read image data to the liquid crystal display panel 20 are both synchronized with the blinking display timing. In particular, image data is read and written immediately after blinking display.

  This is to eliminate the instability of the moving image display that occurs when the read / write timing of the image data deviates from the blinking display timing. Further, when a flat display panel such as a liquid crystal display panel is used as the display means, it is for realizing blinking display in consideration of a reaction time peculiar to the flat display panel. This will be described with reference to FIG.

  FIG. 6 shows the relationship between the blinking display pulse PL and the synchronization signal. When a moving image is constituted by still images of 30 frames per second, first, reading from the image memory 42 is performed in synchronization with a 60 Hz vertical synchronizing signal (pulse) VP (FIG. 6A).

  When the traveling speed of the train 4 is 60 km / h and the repetition frequency of the blinking display pulse PL is set to 30 Hz (FIG. 6B), the image data read / write timing and the blinking display timing are completely synchronized. As a result, even if a plurality of moving images are switched and displayed, the display does not become unstable.

  When the traveling speed deviates from the specified speed, the blinking display timing is deviated from the image data reading and writing timing. For example, when the traveling speed is 10% faster than the specified speed, the blinking display pulse PL is faster than the vertical synchronizing signal VP and the synchronization relationship is shifted (FIGS. 6A and 6C). Due to this shift, the flashing display timing may come before the rewriting of the image data is not completely completed, thereby resulting in unstable moving image display. When a moving image is composed of 24 frames per second, the repetition frequency of the blinking display pulse PL is 24 Hz. In this case, blinking control is performed in the asynchronous mode from the beginning (FIG. 6D).

  Therefore, in the present invention, reading and writing of image data are synchronized with the blinking display pulse PL. That is, immediately after the strobe light is emitted by the blinking display pulse PL, image data to be read out next is read out, and the image data is sequentially written into the liquid crystal display panel 20. Until the next blinking display is performed, the same image data is sequentially rewritten while being read.

  This will be described with reference to FIG. FIG. 7 shows a case of a moving image having a configuration of 30 frames per second, and reading to the image memory 42 is switched at a blinking display timing. The traveling speed of the train 4 is 66 km / h, which is 10% higher than the specified speed.

  FIG. 7A shows image data in field units. Image data Aa (Ba, Ca,...) Read in odd fields and image data Ab (Bb, Cb,...) Read in even fields. Is the same image data A (B, C,...). Accordingly, each of these image data will be described as one frame of image data.

  As shown in FIGS. 7A and 7B, initially (at time t1), the image data Aa is read in synchronization with the vertical synchronization signal VP. In synchronization with this reading, writing to the liquid crystal display panel 20a is performed (FIGS. 7A and 7C). When the writing of the image data Aa for one frame is completed, the image data Ab (= Aa) is read in synchronization with the next vertical synchronization signal VP, and writing (in this case, overwriting) to the liquid crystal display panel 20a is performed. Performed (FIGS. 7A and 7C). Since writing of image data to the liquid crystal display panel 20a must always be performed continuously as is well known, the writing process is performed continuously in units of one vertical cycle.

  On the other hand, according to the above-described example, the cycle of the blinking display pulse PL generated based on the traveling speed of the train 4 is 33 Hz (FIG. 7D), and the blinking display timing comes slightly faster than the second vertical cycle. To do. That is, the timing at the time point t3 before the time point t4 which is the second vertical cycle is the blinking display timing (FIG. 7E).

  At time t3, the image data Ab read immediately before is not written in the liquid crystal display panel 20a but remains slightly for the entire frame. This remaining portion becomes image data that has not been overwritten, but the image data of this unoverwritten portion remains Aa.

  Therefore, the structure of the image data for one frame when the flash is emitted is (Aa + Ab) as shown in FIG. 7E, but both the image data Aa and Ab are part of the same image data A. There is no sense of incongruity as an image of time.

  When the blinking display is made at time t3, reading and writing of the next image data starts almost simultaneously (actually at the timing when the strobe light emission ends) (FIG. 7F). Reading of the image data Ba is performed over a period of one vertical cycle, and is written into the liquid crystal display panel 20a over a period of one vertical cycle (FIG. 7F). The next one vertical cycle is an overwriting process on the image data Ba by the image data Bb. Therefore, from the second blinking display, image data is read and written in synchronization with the vertical synchronization pulse VP ′ (FIG. 7G) synchronized with the blinking display pulse PL.

  The second blinking display is at time t6, which is before time t7 when the second vertical period ends. As a result, as in the case of the first blinking display, the image data Bb read immediately before remains slightly without being written into the liquid crystal display panel 20a for one frame. This remaining portion is the image data Ba that has not been overwritten.

  Therefore, even in the second flashing display, the structure of the image data for one frame when the flash is emitted is mixed image data (Ba + Bb) (FIG. 7F), but the image data Ba and Bb are the same image. The first half of data B and a part of the second half. Therefore, the strobe light is emitted from the image composed of the same image data B.

  Until the next blinking display is performed in this manner, the already written image data of the previous frame is only overwritten, so the blinking display timing is set before the rewriting of the image data for one frame is completed. Even if it arrives, both the image data before rewriting and the image data after rewriting are none other than image data of the same frame. That is, since different image data is written in the same liquid crystal display panel and is not blinked in that state, stable moving image display is achieved.

  In order to realize such image data reading and writing control, the memory selection signal MSa is supplied to the image memory selection unit 48 shown in FIG. 2 together with the blinking display pulse PL, and the first image to be selected by the memory selection signal MSa. The data memories 42A to 42C are designated, and thereafter are sequentially designated in a toggle manner in synchronization with the blinking display pulse PL. Further, the address bus is designated so that the reading from the image data memories 42A to 42C is synchronized with the blinking display pulse PL. By performing such control, the above-described image data read and write processing can be realized.

  Further, as described above, in the case of a flat display panel such as a liquid crystal display panel, the writing is performed only after waiting for a reaction time (response time) Tx peculiar to the apparatus after the writing of the image data is finished. The image cannot be displayed. The reaction time Tx varies somewhat depending on manufacturers and products, but is usually about 16 msec.

Here, the period of the blinking display is 33 msec as apparent from FIG.
33 msec> V + Tx = 16.7 msec + 16 msec
Thus, in the example of FIG. 7, the next image data to be blinked is determined at a time t2 before the blinking display time t3. Since the image data Ab written in the period of the second vertical cycle is the same as the image data Aa written one frame before, the reaction time Tx required until the next image display is sufficiently secured. Therefore, there is no problem.

  In this way, even when a plurality of different still images are switched and displayed at each blinking display timing, a plurality of moving images can be stably displayed.

  Even when a moving image is composed of 24 frames per second, the instability of the moving image is caused in the same manner. In this case, image data is read out and written into the liquid crystal display panel in synchronization with the blinking display pulse. Processing is executed.

  In the case of 24 frames per second, one cycle of the blinking display pulse PL is 42 mS, so that the blinking control is performed between 3 vertical cycles and 4 vertical cycles as shown in FIG.

  FIG. 8 shows an example of the blinking display. Although the detailed description thereof is omitted, the blinking display timing is a time point t3 before the time point t4 in the fourth vertical cycle (FIGS. 8C and D). This timing is in the middle of overwriting the image data Ac in the fourth vertical cycle on a part of the image data Ab written one frame before. Therefore, the image data displayed in a blinking manner is (Ac + Ab) mixed data (FIG. 8E), but since Aa = Ab = Ac = A, a moving image based only on the still image A is displayed. Therefore, the moving image is not uneven. Further, it can be easily understood that the reaction time Tx of the liquid crystal display panel 20 is sufficiently cleared. The same applies to the next blinking display timing.

  Accordingly, even when a moving image is displayed at 24 frames per second, it is possible to stably display even a plurality of different moving images by synchronizing the reading and writing timing of image data with the blinking display timing. .

  FIG. 9 is an example of a video display device 100 having a so-called seamless structure in which the liquid crystal display panel 20 installed in the tunnel 5 is arranged without interruption.

  In this case, when a still image of one frame is displayed on one liquid crystal display panel, it is as shown in FIG. For example, when the width (size) of the liquid crystal display panel 20 is 47 cm, a traveling speed (specified speed) for displaying a still image of one frame on one liquid crystal display panel in order to show 30 images per second. Is 50 km / h.

  Therefore, the relationship between the three still images A, B, and C different from each liquid crystal display panel 20 is as shown in FIG. Even in such a seamless configuration, by performing the same control as in the first embodiment, a plurality of moving images can be stably displayed even when a plurality of different still images are switched and displayed at each blinking display timing.

  FIG. 11 shows a configuration example of a distribution system that distributes image data for still images via a network.

  As shown in FIG. 11, the image data is first supplied from a distribution center (external distribution apparatus) 80 to the cluster masters 95a, 95b,... 95n via the network 90, and the cluster masters 95a, 95b,. 95n to the video display devices 100a, 100b,... 100n. In the video display devices 100a, 100b,... 100n, unit masters 110a, 110b,... 110n are provided, and liquid crystal displays as respective display means via the unit masters 110a, 110b,. Supplied to the device 11. Therefore, the unit masters 110a, 110b,... 110n in this case correspond to the control unit 12 shown in FIG.

  When the distribution system is constructed in this way, the video display device 100 is not installed only in a single tunnel but is installed in a plurality of tunnels on the same route, as well as in the same series of railway transportation companies. There is an advantage that the video display apparatus 100 can be managed collectively.

  In the above-described embodiment, the CPU 60 is used as the control unit 12, but the present invention is not limited to this. For example, you may use the hardware which comprises a control circuit. In this case, high-speed processing can be realized.

  In the above-described embodiment, the description has been given of the case where the speed detection unit 13 is provided on the liquid crystal display panel 20 side that enters the earliest when the train approach direction is used as a reference. You may make it provide the speed detection part 13 also in the side. In this case, even if the train (moving body) 4 enters from both of the installed liquid crystal display panels 20, it can cope simultaneously.

  In the first to third embodiments, the case where a flat display panel such as an LCD, particularly a full-size flat display panel is used as the display panel 20 provided in the display unit 6 is shown. In the present invention, a strip-shaped flat display panel configured in a size other than the full size can be applied as the flat display panel.

  For example, as shown in FIG. 12, there is a full-size flat display panel 200 composed of m pixels in the horizontal direction and n pixels in the vertical direction. A strip-shaped display panel 120 composed of one pixel and n pixels in the vertical direction can be used as the display panel of the video display device according to the present invention.

  As such a strip-shaped display panel 120, a light emitting display element (LED) such as a light emitting diode is suitable instead of an LCD. By using a light emitting diode, a strip-shaped display panel can be easily manufactured and the cost can be greatly reduced. Furthermore, it is because installation is easy if it is strip-shaped. When a color display panel is configured by using light emitting diodes, for example, as shown in FIG. 13, three light emitting diodes 122R, 122G, and 122B that emit light of R, G, and B primary colors are arranged in-line. Pixels can be configured.

  When such a strip-shaped display panel 120 is used, the still image data S1, S2, and the vertical line of still image data S1, S2, and m pixels as shown in FIG. By sequentially reading and displaying all the image data S3,... Sm, a still image (full size) for one screen can be displayed even with the strip-shaped display panel 120 for one pixel. Then, this can be displayed as a moving image by blinking the display every vertical scanning period. The number of horizontal pixels m is usually 320 or 640, and the number of vertical pixels n is about 240.

  FIG. 14 shows an example of the display control unit 150 in the LED display device 300 of the video display device using the display panel 120 for one vertical line composed of (m = 1, n) pixels. Since the basic configuration of the display control unit 150 follows the configuration of the display control unit 40 shown in FIG. 2, the same reference numerals are given to the overlapping portions, and the description thereof is omitted.

  When a self-luminous element such as an LED is used as the display panel 120, a light emitting device such as a backlight is not necessary as in the case of an LCD, and image data is written in consideration of the reaction time of an LCD. Processing is also unnecessary. Therefore, as shown in FIG. 14, an LED drive unit 130 is provided, and a drive pulse generated by the LED drive unit 130 is supplied to the display panel 120 as a blinking display pulse PL ′ (see FIGS. 15B and 15C).

  Further, a vertical line selection unit 140 is provided between the memory means 42 and the image memory selection unit 48, and still image data divided into m is sequentially selected for each vertical line. The selection timing is synchronized with the blinking display pulse PL ′ described above. Accordingly, still image data Si for one vertical line is read from the specific memory selected by the image memory selection unit 48 and supplied to the corresponding pixels Pi (i = 1 to 240) of the display panel 120. Then, by supplying the blinking display pulse PL ′, all the pixels Pi for one vertical line are lighted and displayed simultaneously.

  This display process is continuously performed within the display period of the one blinking display pulse PL ′, and the still image data for one vertical line is sequentially read out by repeating the total m times while sequentially shifting in the horizontal direction. It is supplied to the display panel 120. By displaying this divided image continuously for m times within the display period of one blinking display pulse PL ′, a still image for one screen can be displayed.

  As shown in FIG. 12, in the case of a display panel in which one screen (full size) is composed of horizontal 320 (= m) pixels and vertical 240 (= n) pixels, within the display period of one blinking display pulse PL ′. In order to display the divided images S1, S2,... Sm of all the vertical lines, the pulse width of the blinking display pulse PL ′ is selected to be approximately 100 nsec (see FIG. 15C).

  Thus, even if the strip-shaped display panel 120 is used, if all the still images (strip images) divided into m can be displayed within the display period of the one blinking display pulse PL ′, the viewer can use the full size (1 It is possible to see the same image as the still image displayed on the screen. That is, the same display state can be realized as when a single still image is displayed using a full-size two-dimensional flat display panel.

  Since the strip-shaped display panel 120 is used, the unit price of the display panel is very low. Therefore, it is difficult to be limited by the number of sheets used, the installation location is not limited, the installation man-hour is low, and the periphery of the display panel 120 The advantages of the strip-shaped display panel, such as the simplification of the drive circuit system, can be mentioned.

  In the strip-shaped display panel 120, the number of pixels in the horizontal direction is not limited to m = 1. For example, m = about 10-50 is possible. With this number of pixels, manufacturing is easy and control is easy. For example, when the number of full-size horizontal pixels is 320 pixels (= m) and m = 10, a two-dimensional display panel is formed in a strip shape in which 10 pixels are arranged in the horizontal scanning direction. In this case, since one screen may be divided into 32 in the horizontal scanning direction and sequentially switched and displayed, the configuration of the display control unit 150 is simplified.

  The video display device and video display method according to the present invention can be used as an advertising medium in places such as subways and amusement parks.

It is explanatory drawing which shows the outline of embodiment in the case of using this invention in a tunnel. It is a systematic diagram of the principal part which shows the relationship between the display control part provided in the video display apparatus, and a liquid crystal display panel. It is a systematic diagram of the principal part which shows an example of the control part provided in the video display apparatus. It is explanatory drawing for displaying a several different still image. It is the explanatory drawing. It is a timing chart which shows the relationship between a vertical synchronizing signal and a blinking display pulse. It is explanatory drawing which shows the example of a blink display process when it is set as 30 frames per second. It is explanatory drawing which shows the example of a blink display process when it is set as 24 frames per second. It is a figure which shows the other example of the video display apparatus when it is set as a seamless structure. It is a figure which shows the example of a display process. It is a figure which shows the structural example of the image delivery system via a network. It is a pixel block diagram for demonstrating the other Example of this invention. It is a conceptual diagram of the strip-shaped display panel used for the other Example of this invention. It is a block diagram of the principal part which shows the structural example of the display control part when using the strip-shaped display panel of FIG. It is a wave form diagram which shows the relationship with the drive pulse used at that time. It is a block diagram which shows an example of the conventional video display apparatus. It is a figure which shows the example of a single moving image display. It is a figure which shows the example of a several different moving image display (the 1). It is a figure which shows the example of a several different moving image display (the 2).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 (100a-100n) ... Video display apparatus, 4 ... Train (moving body), 5, 5a ... Tunnel and wall surface, 11 ... Display means (liquid crystal display panel), 11a-11n ... Liquid crystal display panel, 12 ... control unit, 13 ... speed detection unit, 60 ... CPU, 20 ... display panel, 30 ... light emitting device, 40, 150 ... display control unit, 42 ... Image memory, 42A to 42C ... Image data memory, 44 ... Communication control unit, 46 ... LCD drive unit, 48 ... Image memory selection unit, 50 ... Light emission drive unit , Distribution center (external distribution device), 80 ... network, 95a to 95n ... cluster master, 120 ... strip-shaped display panel, 130 ... LED drive unit, 140 ... vertical line selection unit

Claims (10)

In a video display device that provides continuous video by the still image by blinking and displaying still images supplied to a plurality of display means arranged at predetermined intervals along the path of the moving body,
A plurality of display means having a display panel arranged in a site that can be seen from the mobile body by a passenger of the mobile body;
Speed detecting means for detecting the traveling speed of the moving body;
Based on the traveling speed of the moving body obtained from the speed detection means, a control unit that generates a blinking display pulse supplied to the display means,
In order to sequentially display still images on a display panel provided for each of the display means, an image memory for storing a plurality of different still image data, and a light emission driving unit for the display panel to which the blinking display pulse is supplied It consists of a display control unit,
In the display control unit, the video display device is configured to perform writing control in which the plurality of still images are sequentially selected and the still image data is written on the display panel. The selection of the still image data in the image memory selection unit and the writing process to the display panel are performed in synchronization with the blinking display pulse,
2. An image memory selection unit in which the still image data is written immediately after the blinking display by the blinking display pulse in synchronization with the blinking display pulse is provided in the display control unit. The video display device described. The video display device according to claim 1, wherein different still image data is displayed on the adjacent display panels, and different still images are displayed. The video display device according to claim 1, wherein the display panel is a full-size two-dimensional flat display panel, and a liquid crystal display panel is used. The display panel is a strip-shaped flat display panel, and a full-size still image is divided and displayed,
Among the full-size still image data, still image data matching the display size of the display panel is sequentially supplied, and a part of the full-size still image is sequentially displayed, thereby displaying the flashing display pulse. The video display apparatus according to claim 1, wherein a full-size still image is displayed within a period. 6. The video display device according to claim 5, wherein the display element used in the strip-shaped flat display panel is a light emitting diode. A video display method for providing a continuous video by the still image by blinking and displaying a still image supplied to a plurality of display means arranged at predetermined intervals along a path of a moving body,
A first step of supplying a plurality of different still images to the same display means and sequentially displaying blinking at predetermined intervals;
A video display method comprising: a second step of writing image data of the still image to the display means in synchronization with a flashing display pulse for light emission supplied to the display means. In the second step, the still image is written to the display means immediately after the blinking display by the blinking display pulse in synchronization with the blinking display pulse for causing the display means to emit light. The video display method according to claim 5. When the display means is a strip-shaped flat display panel, a full-size still image is divided and displayed on the flat display panel,
Of the full-size still image data, still image data that matches the display size of the display panel is sequentially supplied, and a part of the still images of a plurality of sizes are sequentially displayed, thereby displaying the flashing display pulse. The video display method according to claim 7, wherein a full-size still image is displayed within a period. The video display method according to claim 7, wherein the display element used in the strip-shaped flat display panel is a light emitting diode.

Images