JP2009122412A - Image display system and image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display system capable of perfoming synchronized image display by a plurality of image display devices without reference to the kind of contents to be displayed. <P>SOLUTION: In the image display system 1, an image output device 11 includes an index signal generator 113 which generates a timing index signal and inserts it into an image signal, and an image signal transmitter 114 which transmits the image signal into which the timing index signal is inserted to image display devices. The image display devices 12 and 13 each have a timing index signal decoder 126 which decodes the timing index signal inserted into the image signal and a timing index signal transmitter 127 which transmits the decoded timing index signal to the other image display device 12 or 13, so that image display is synchronized through the transmission of the timing index signal. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image display system and an image display device.

2. Description of the Related Art Conventionally, a multi-projection system that performs projection by configuring a single display by combining a plurality of projectors is known.
For example, as such a multi-projection system, a tiling projection system (a multi-projection system in a narrow sense) that provides a high-resolution image by spatially adjoining a plurality of projectors, or the projection position of each projector is the same position In this way, a stacking projection system that provides a high-luminance video can be used.
In these methods, it is necessary to control and process an image input to each projector so that a plurality of projectors operate integrally.
These are generally performed using a PC, but in that case, it is difficult to update frames at the same timing for a plurality of projectors.

This is because the update timing input to each projector is shifted. Especially for inputs from different image output devices (graphic cards) and different PCs, it is difficult to synchronize the update timings unless expensive dedicated hardware is used.
As a method to solve such problems, in a multi-projection system using a PC, the frame playback speed of the moving image is compared with the playback speed of the display device, and the display is adjusted to the slowest playback speed. A method of transmitting a synchronization signal for performing has been proposed (see, for example, Patent Document 1).

JP 2005-86592 A

However, the method disclosed in Patent Document 1 is effective for a frame playback speed given as in MPEG, but a slideshow that displays contents while switching them, such as a slide show, a desktop, etc. The display itself cannot be supported.
Also, if the video is displayed as a window on a part of the screen instead of being displayed on the entire screen, the entire frame will be matched to the frame playback speed, and the display frame that the observer is aware of There is a possibility of deviation from the rate.
These problems can be grasped as similar problems not only in the projection system but also in the case where a normal display is arranged in a plurality of spatially adjacent positions.

  An object of the present invention is to provide an image display system and an image display device that can perform synchronized image display by each image display device regardless of the type of content to be displayed.

An image display system according to the present invention includes:
An image display system comprising an image output device that outputs an image of a frame unit as an image signal, and a plurality of image display devices connected to the image output device,
The plurality of image display devices are connected to each other so as to be capable of bidirectional communication,
The image output device includes:
An image signal generator for generating an image signal for displaying an image on each image display device;
An image signal transmission unit that transmits the image signal generated by the image signal generation unit to each image display device at a predetermined timing; and
A timing index signal generation unit that generates a timing index signal that synchronizes display by each image display device according to a predetermined timing at which the image signal is transmitted;
A timing index signal transmitter that transmits the timing index signal generated by the timing index signal generator to each image display device;
The image display device includes:
An image signal receiving unit for receiving the image signal transmitted from the image signal transmitting unit;
An image signal storage unit for storing the image signal received by the image signal reception unit in units of frames;
An image display unit that displays an image in units of frames based on the image signal stored in the image signal storage unit;
A timing index signal receiving unit that receives the timing index signal transmitted from the timing index signal transmitting unit;
A timing index signal transmitting unit that transmits the timing index signal received by the timing index signal receiving unit to a timing index signal receiving unit of another image display device;
A timing index signal reception monitoring unit that monitors whether or not the timing index signal transmitted from the image output device is received by another image display device;
When the timing index signal reception monitoring unit determines that the timing index signal has been received by all the image display devices, the image display unit receives the frame-based image signal stored in the image signal storage unit. And an image display control unit for displaying an image.

Here, the transmission of the timing index signal may use a transmission system that transmits an image signal. A transmission system that connects the image output device and each image display device is provided separately from the transmission system that transmits the image signal. The transmission may be performed via this transmission system.
In short, the timing index signal may be any signal that can recognize what kind of image the image signal transmitted from the image output apparatus displays on the image display apparatus. For example, the image signal transmission is performed on the image output apparatus side. The time from the start may be initialized and the time information of the transmitted image signal may be used, or the number of frame updates of the image signal output from the image output device from the start of image signal transmission may be used.
Furthermore, the transmission system for connecting the image display apparatuses to each other is only required to be capable of bidirectional communication between the image display apparatuses, and for example, USB (Universal Serial Bus), LAN (Local Area Network), etc. can be adopted. .

  According to the present invention, the image output device includes a timing index signal generation unit and a timing index signal transmission unit, and the image display device includes a timing index signal reception unit, a timing index signal transmission unit, a timing index signal reception monitoring unit, and an image display. By providing the control unit, when it is determined that all the image display devices have received the timing index signal, the image display by each image display device is started. Therefore, regardless of the type of content to be displayed Thus, it is possible to synchronize the display of each image display device, and even if one content is displayed simultaneously on a plurality of image display devices, the viewer does not feel uncomfortable.

In the present invention, the image output device comprises:
The timing index signal generation unit inserts the generated timing index signal into the image signal generated by the image signal generation unit,
The timing index signal transmission unit is also used as the image signal transmission unit,
The image display device includes:
A timing index signal decoding unit that decodes and extracts the timing index signal inserted by the timing index signal generation unit;
It is preferable that the timing index signal receiving unit is also used as the image signal receiving unit.
According to the present invention, since the timing index signal is inserted into the image signal by providing the timing index signal generation unit and the timing index signal decoding unit, each image display can be performed only by transmitting the image signal from the image output device. The display on the device can be synchronized.
Further, it is not necessary to provide a timing index signal transmission system separately from the image signal transmission system, so that the transmission system of the image display system can be simplified.

In the present invention, the image signal is provided to each of a plurality of pixels constituting a frame image, and includes color display data including a plurality of bit strings for performing color display on each pixel,
The timing index signal is preferably inserted into a predetermined bit string from the LSB (Least Significant Bit) to the upper part of the bit string of the color display data of at least one of the pixels.
Specifically, the color display data consists of a bit string of at least 9 bits,
The timing index signal is preferably inserted into a bit string lower than 8 bits.

Here, the timing index signal may be inserted into the color display data given to one pixel constituting the frame image, or may be inserted across the color display data given to a plurality of pixels.
According to the present invention, the timing index signal can be easily inserted into the predetermined bit sequence from the LSB to the higher order in the bit sequence of the color display data of the pixel without changing the data configuration of the image signal. The signal can be inserted into the image signal.
In addition, by inserting the timing index signal into the lower part of the bit string that gives the color display data, the change in the color display data given to the pixels is reduced, and the image quality of the image displayed on the image display device is deteriorated. You can reduce it.

In particular, by inserting a timing index signal into a bit string lower than 8 bits, the color display data of an image signal such as an RGB signal is based on 8 bits. Can be minimized.
Note that data such as color unevenness correction data and luminance unevenness correction data of each pixel is normally inserted into a bit string lower than 8 bits. Therefore, even if these data are replaced with timing index signals, the degree of correction of color unevenness and brightness unevenness only slightly changes, and color display data of one pixel is displayed on the image display device. There is almost no effect on the image to be displayed. Even when the timing index signal is inserted into the color display data of a plurality of pixels, image quality degradation of an image displayed on the image display device can be suppressed as much as possible by selecting pixels discretely.

In the present invention, the timing index signal is preferably inserted into color display data given to a specific pixel among a plurality of pixels constituting the frame image of the image signal.
Here, if the specific pixel is a fixed pixel type display such as a liquid crystal display or an organic EL display, an observer usually displays a pixel having a pixel defect or an image displayed by an image display device. For example, it refers to a pixel at a corner, etc. that is not often seen.
According to the present invention, since the timing index signal can be expressed by all the bit strings constituting the color display data by inserting the timing index signal into the color display data given to the specific pixel, one pixel The timing index signal can be inserted only with the color display data given to.
In addition, since a specific pixel is a pixel having a pixel defect or a corner corner pixel, a change in the display image by the image display device due to the insertion of the timing index signal is hardly visually recognized. The observer does not recognize the deterioration in the image quality of the display image.

In the present invention, the image display device includes a light source, a light modulation device that modulates light emitted from the light source according to an image signal to form an optical image, and an optical image formed by the light modulation device. When the projector includes a projection device for projecting, and a tiling display in which a part of the projection area of each projector is superimposed,
The timing index signal is preferably inserted into color display data provided to pixels constituting a frame image of an image signal corresponding to the overlapping area of each projector.

In the tiling display by the projector, when a part of the projection image by the adjacent projector is overlapped, the light from each projector is overlapped, and the part of the overlap region becomes brighter than the part of the other projection image. For this reason, in the tiling display, it is usual to perform a dimming process on an overlapped area portion by an optical method or correction of an image signal to obtain a seamless seamless image.
Therefore, for example, even if the color display of the pixel in the overlapping region of one projection image changes due to the insertion of the timing index signal, it can be compensated by the other projection image to be superimposed. Observer becomes difficult to recognize.

The present invention can also be configured as an image display device as a sub-combination constituting the image display system described above.
Specifically, an image display that connects a plurality of image display devices to an image output device that outputs an image in frame units as an image signal, and displays the image signal output from the image output device on each image display device. An image display device used in the system,
A terminal to which a transmission system capable of bidirectional communication with other image display devices is connected;
An image signal receiving unit for receiving an image signal transmitted from the image signal output device;
An image signal storage unit for storing the image signal received by the image signal reception unit in units of frames;
An image display unit that displays an image in units of frames based on the image signal stored in the image signal storage unit;
A timing index signal receiving unit that receives a timing index signal that is generated by the image output device and that synchronizes display timing of an image signal to be displayed according to a predetermined timing at which the image signal is transmitted;
A timing index signal transmitting unit that transmits the timing index signal received by the timing index signal receiving unit to a timing index signal receiving unit of another image display device;
A timing index signal reception monitoring unit that monitors whether or not the timing index signal transmitted from the image output device is received by another image display device;
When the timing index signal reception monitoring unit determines that the timing index signal has been received by all the image display devices, an image is displayed on the image display unit based on the image signal stored in the image signal storage unit. And an image display control unit to be operated.

[First Embodiment]
FIG. 1 shows a multi-projection system 1 as an image display system according to a first embodiment of the present invention. The multi-projection stem 1 includes a computer 11 as an image output device, projectors 12 and 13 that form projection images, a computer 11 and image transmission cables 14 and 15 that connect the projectors 12 and 13, and projectors 12 and 13. A cable 16 is provided to connect each other.
The projectors 12 and 13 are arranged so that a part of each of the projection images 17 and 18 is overlapped. The computer 11 cuts out the original image into two right and left divided images, and one of the divided images is given to the projector 12. The other divided image is displayed on the projector 13. Thereby, the multi-projection system 1 realizes a large-screen and high-resolution tiling display in which the projection images 17 and 18 are combined. In the present embodiment, the tiling display in which a part of the projection images 17 and 18 of the two projectors 12 and 13 are overlapped is used. However, the present invention is not limited to this. It is good also as a stacking display to increase the brightness.

As will be described in detail later, the computer 11 generates divided images of a presentation image displayed by an application operating on the OS, and displays the divided images on the projectors 12 and 13, and two video cards are provided. The projectors 12 and 13 are connected to the respective video cards.
The projectors 12 and 13 include a light source, a light modulation element such as a liquid crystal panel that modulates a light beam emitted from the light source according to image information to form an optical image, and a projection optical device that projects the formed optical image. And a control board for electrically driving and controlling the light source and the optical engine.

The image transmission cables 14 and 15 connecting the computer 11 and the projectors 12 and 13 are DVI (Digital Visual Interface) standard cables capable of digitally transmitting image information. Image signals in units of frames are transmitted to the projectors 12 and 13 through the image transmission cables 14 and 15 at a predetermined frame rate.
A cable 16 for connecting the projectors 12 and 13 is a USB cable or the like capable of two-way communication. The projectors 12 and 13 can communicate with each other. In the present embodiment, the projectors 12 and 13 are separately installed and tiling display is performed. However, the present invention is not limited to this, and the optical engines and control boards constituting the projectors 12 and 13 are provided in the same casing. You may store in. In this case, since the control boards of the projectors 12 and 13 are exposed in the housing, the boards may be directly connected to each other without using a USB cable.

In such a multi-projection system 1, when the presentation images are displayed by the projection images 17 and 18 in the respective projectors 12 and 13, it is difficult to synchronize the update timing of the frames of the respective projection images 17 and 18, and the observer May cause discomfort.
The reason for this is that, first, the update timing of image signals transmitted from two video cards attached to the computer 11 is difficult to synchronize because each video card is independent. In the point. To solve this, expensive dedicated hardware must be used to synchronize as described above.

Second, even if the timing of the image signals transmitted from the respective video cards of the computer 11 is synchronized, the timing of the image display between the projectors 12 and 13 is not synchronized. However, the display is shifted.
That is, in the projectors 12 and 13, the image signal transmitted from the computer 11 is written on the frame buffer provided on the control board, and when the image signal for one frame is written, the image display unit of the projectors 12 and 13. The projection image is formed by displaying an image for one frame by the (drive circuit), but the timing of writing to the frame buffer of each projector 12 and 13 is not synchronized, and either projector A display shift occurs due to a writing delay of 12 and 13 and the like.

For example, if the flow of the image signal of computer 11 → image transmission cable 14 → projector 12 is system 1, and the flow of image signal of computer 11 → image transmission cable 15 → projector 13 is system 2, as shown in FIG. Normally, the image display timing in the system 1 and the image display timing in the system 2 are not synchronized.
No. from computer 11 If the image update command for the image 101 is simultaneously transmitted to the system 1 and the system 2, the update timing is early in the system 1. The writing of the image signal 100 is completed earlier in time, 101 image signal writing can be started.
On the other hand, in system 2, No. to the frame buffer. Since the writing of the 100 image signals has not been completed, it is necessary to wait for this. No. 100 waits for the completion of the writing of the 100 image signal. It is necessary to start the writing of the image signal 101, and the update timing of the projection images 17 and 18 in the system 1 and the system 2 is shifted.

Therefore, in the present embodiment, as shown in FIG. 3, the projectors 12 and 13 are connected to each other via a cable 16 so as to be capable of bidirectional communication, and a divided image signal VIDEO1 for each frame is transmitted from the computer 11 to the system 1. 2 is accompanied by timing index signals TIS1 and TIS2 representing the divided image signals VIDEO1 and VIDEO2, when the divided image signal VIDEO2 for each frame is transmitted. In the frame buffer of system 1, No. When the writing of the divided image signal VIDEO1 of 100 is completed, the timing index signal TIS1 is transmitted from the projector 12 to the projector 13, and No. 2 is stored in the frame buffer of the system 2. When the writing of the 100 divided image signals VIDEO2 is completed, the projector 13 is configured to transmit the timing index signal TIS2 to the projector 12.
Then, on the condition that the timing index signals TIS1 and TIS2 are transmitted from all the projectors 12 and 13, the display between the projectors 12 and 13 is synchronized by starting the image display by the projectors 12 and 13. And the above-mentioned problem was solved.
Hereinafter, a detailed configuration of the multi-projection system 1 will be described.

FIG. 4 is a block diagram of the multi-projection system 1 according to this embodiment.
A computer 11 as an image output device constituting the multi-projection system 1 includes a display driver 111 that is activated on the OS. The display driver 111 includes an image generation unit 112, a timing index signal insertion unit 113, and an image signal transmission unit 114. It has.
An image generation unit 112 as an image signal generation unit is a part that generates a divided image signal from original image data such as a desktop displayed on a computer screen. In this embodiment, as shown in FIG. Two divided image signals are generated from the image data. The divided image signal is configured as color display data given to each pixel constituting the image forming area of the light modulation element, and the color display data given to each pixel is composed of, for example, a 16-bit bit string. The color display data is configured as data of three colors of R, G, and B, and the color display data of each color is configured as data that gives gradation display for 8 bits from the MSB (Most Significant Bit), and below that. Includes data for correcting luminance unevenness, color unevenness, ghost, and the like.

The timing index signal insertion unit 113 as a timing index signal generation unit is a part that generates a timing index signal and inserts the generated timing index signal into the divided image signal generated by the image generation unit 112.
The timing index signal is a signal that represents the index of the image to be updated. For example, the frame number of the updated image, or the process after the computer 11 is started and the generation of the divided image by the image generation unit 112 is started. It is configured as numerical data such as time. Note that the timing index signal is not necessarily inserted into all the divided image signals by the timing index signal insertion unit 113, but may be inserted every several frames within a range in which the projectors 12 and 13 can synchronize the display of the projected image. Good.
For example, as illustrated in FIG. 5, the timing index signal insertion unit 113 inserts a timing index signal into four bit strings on the LSB side of 16-bit color display data for any of R, G, and B colors. . In this case, the color display data into which the timing index signal is inserted may be one pixel or may be inserted using a plurality of pixels. In short, it is only necessary to insert the bit into a bit where the color display data changes greatly and does not cause image quality deterioration such as different color display of the projected image.

As another method, as shown in FIG. 6, a timing index signal may be inserted into the overlapping area A1 of the projection images 17 and 18 and the corner area A2 of the projection images 17 and 18. .
In the overlapping area A1, each projector 12, 13 is provided with a light shielding plate and the like so as to perform optical dimming processing so that the boundary portion is not conspicuous. Even if the timing index signal is inserted into the display and the color display is different, it is buried by the projection image from the other projector 13. Further, since the right end portion of the projection image 17 of the projector 12 is almost black, the portion is shielded from light by the light shielding plate even if the timing index signal is inserted using all 16 bits. Therefore, an observer does not visually recognize.
In addition, in the corner corner area A2, since the observer is usually gazing at the center of the projection image, even if a color change occurs in this area, the viewer does not notice.

Returning to FIG. 4, the image signal transmission unit 114 is a part that transmits the divided image signal generated by the image generation unit 112 and inserted with the timing index signal to the projectors 12 and 13 via the video cards 115 and 116. Yes, for example, the divided image signal is transmitted at an update cycle of about 1/60 s to 1/72 s.
The transmitted divided image signal is input to the video input terminals 121 of the projectors 12 and 13 via the video cards 115 and 116 and the image transmission cables 14 and 15.

The projectors 12 and 13 are devices that display a projected image at a predetermined update cycle based on the divided image signal input to the video input terminal 121, and include an image signal receiving unit 122, a frame buffer 123, an image display unit 124, and an image. The display control unit 125, the timing index signal decoding unit 126, the timing index signal transmission unit 127, and the timing index signal reception monitoring unit 128 are configured.
The image signal receiving unit 122 is a part that receives the divided image signal input to the video input terminal 121 and writes it to the frame buffer 123.
The frame buffer 123 serving as an image storage unit is a part that stores and holds the received divided image signal. Based on a command from the image display control unit 125, the frame buffer 123 stores the stored image signal for one frame as an image display unit. It outputs to 124.
The image display unit 124 is configured as a drive circuit that drives and controls the light modulation element, and performs drive control of the light modulation element based on the image signal from the frame buffer 123.

The image display control unit 125 is a part that controls the frame buffer 123 and the image display unit 124, and performs drive control based on a monitoring state of a timing index signal reception monitoring unit 128 described later.
The timing index signal decoding unit 126 is a part that decodes the timing index signal inserted into the divided image signal by the timing index signal insertion unit 113 of the computer 11.
The timing index signal transmission unit 127 is a part that transmits the timing index signal decoded by the timing index signal decoding unit 126 to another projector 13 via the USB port 129 and the cable 16.
The timing index signal transmission unit 127 transmits a signal “No Buffered” indicating that the writing has not been completed yet when the writing of the image signal to the frame buffer 123 has not been completed. The transmission of the timing index signal is performed at a timing shorter than the image update period of the projectors 12 and 13.
The timing index signal reception monitoring unit 128 is a part that monitors whether or not a timing index signal is transmitted from another projector 13 via the cable 16, and outputs a monitoring state to the image display control unit 125.

Next, the operation of this embodiment will be described based on the flowcharts shown in FIGS.
First, as illustrated in FIG. 7, the image generation unit 112 of the computer 11 generates a divided image signal in frame units according to the projection images 17 and 18 (step S <b> 1).
The timing index signal insertion unit 113 generates a timing index signal, and inserts the generated timing index signal into the divided image signal generated by the image generation unit 112 (step S2).
When the timing index signal is inserted into the divided image signal, the image signal transmission unit 114 transmits the divided image signal to the projectors 12 and 13 via the video cards 115 and 116 (step S3).

The transmitted divided image signal is received by the image signal receiving unit 122 from the video input terminals 121 of the projectors 12 and 13 (step S4), and the image signal receiving unit 122 writes and stores the received divided image signal in the frame buffer 123. (Procedure S5).
When the frame-by-frame image signal is written in the frame buffer 123, the timing index signal decoding unit 126 decodes the timing index signal inserted into the image signal (step S6), and acquires the timing index signal (step S7).

As shown in FIG. 8, when the timing index signal is acquired, the timing index signal transmission unit 127 identifies the oldest timing index signal owned by itself (step S <b> 8) and sets the oldest timing to the other projectors 12 and 13. While transmitting the signal, the timing index signal reception monitoring unit 128 monitors the reception state of the timing index signal from the other projectors 12 and 13 (step S9).
The timing index signal reception monitoring unit 128 determines whether or not the timing index signal from the other projectors 12 and 13 is “No Buffered”, and if “No Buffered” is present, the procedure from Step S8 is repeated ( Procedure S10).

On the other hand, when the timing index signal reception monitoring unit 128 determines that the timing index signal from the other projectors 12 and 13 has a value for specifying an image such as the frame number of the updated image, the timing index signal reception monitoring unit 128 The fact is output to the image display control unit 125, and the image display control unit 125 outputs the divided image signal stored in the frame buffer 123 to the image display unit 124 (step S11).
The image display unit 124 displays a projection image based on the divided image signal stored in the frame buffer 123 (step S12), and the image display control unit 125 displays the displayed image stored in the frame buffer 123. The signal is deleted (step S13).

According to the present embodiment, since the display timing of the projection images 17 and 18 by the projectors 12 and 13 is performed based on the detection of the timing index signal, the projection images 17 and 18 of the projectors 12 and 13 are displayed. The display timing can be synchronized, and the display by the projectors 12 and 13 can be synchronized regardless of the type of display content such as a moving image such as MPEG or the desktop of the computer 11.
Further, by inserting the timing index signal into the image signal, the synchronization timing index signal can be transmitted to the projectors 12 and 13 using the image signal transmission system, so that the transmission system can be simplified.

Further, by inserting the timing index signal on the LSB side of the bit string of the image signal, it is possible to minimize the deterioration of the image, which may cause the viewer of the projected images 17 and 18 to feel uncomfortable. Absent.
In addition, by inserting the timing index signal into the color display data provided to the pixels in the overlapping area A1 and the corner area A2 in tiling display, the image quality deterioration due to the change in the color display data is given to the observer. It can be made difficult to see.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the following description, the same parts as those already described are denoted by the same reference numerals, and the description thereof is omitted.
In the multi-projection system 1 according to the first embodiment described above, two projectors 12 and 13 are connected to one computer 11, and partial images displayed on the projectors 12 and 13 in the image generation unit 112 of the computer 11. It was configured to generate a signal.
In contrast, in the multi-projection system 2 according to the second embodiment, as illustrated in FIG. 9, the server 20 and the computers 21, 22, and 23 are connected to each other via a network 27, and the computers 21, 22 are connected. , 23 are connected to one projector 24, 25, 26, respectively.

As shown in FIG. 10, the computer 21, 22, 23 and the projector 24, 25, 26 are connected in a one-to-one correspondence with the computer 21, 22, 23 and the projector 24, 25, 26. The basic configuration is the same as that of the first embodiment.
That is, each of the computers 21, 22, and 23 includes an image generation unit 112, a timing index signal insertion unit 113, an image signal transmission unit 114, and a video card 115. The configuration and operation of each part are the same as those in the first embodiment. is there.
Each projector 24, 25, 26 also has a video input terminal 121, an image signal receiving unit 122, a frame buffer 123, an image display unit 124, an image display control unit 125, a timing index signal decoding unit 126, and a timing index signal transmission unit 127. The timing index signal reception monitoring unit 128 and the USB port 129 are provided, and the configuration and operation of each part are the same as those in the first embodiment.

In such a multi-projection system 2, the generation of divided images by the image generation unit 112 in the computers 21, 22, and 23 on the network 27 is synchronized based on a control command from the server 20.
Each computer 21, 22, 23 inserts timing index signals TIS 1 -TIS 3 into the generated divided image signals VIDEO 1 -VIDEO 3 and transmits them to the projectors 24, 25, 26.

  Even in such a case, for example, as shown in FIG. 9, a difference may occur in the divided image signals written in the frame buffer 123. For example, in the projector 24 of the system 1, the frame No. 100-No. 103 is stored, and the projector 25 of the system 2 has a frame No. 100 image signals are being written. In the projector 26 of the system 3, the frame No. Assuming that the image signal 101 is being written, the projector 24 of the system 1 receives the frame No. as the oldest index in the frame buffer 123. 100 is transmitted from the USB port 129 to the other projectors 25 and 26 as the timing index signal TIS1. The projector 3 of the system 3 also has a frame No. Since the writing of 100 is finished, the frame number is similarly set as the timing index signal TIS3. 100 is transmitted to the projectors 24 and 25.

On the other hand, the projector 25 of the system 2 has a frame No. Since the writing of the 100 image signals is not completed, a signal “No Buffered” indicating that writing is in progress is transmitted to the projectors 24 and 26 as the timing index signal TIS2.
Then, the frame number to the frame buffer 123 of the projector 25 of the system 2 is displayed. When the writing of 100 is completed, the frame No. When “100” is transmitted to the projectors 24 and 26 as the timing index signal TIS2, “No Buffered” disappears in all the timing index signals TIS1 to TIS3. An image corresponding to 100 is displayed.

The multi-projection system 2 according to the second embodiment has the following effects in addition to the effects described in the first embodiment.
That is, by generating the divided image signals using the plurality of computers 21, 22, and 23, the processing load on each of the computers 21, 22, and 23 is reduced, so that the time required for image display can be shortened. it can. In particular, even a full high-definition image such as 4K2K (4096 pixels × 2160 pixels) can be displayed in a short time by generating divided image signals with the plurality of computers 21, 22, and 23. Therefore, even if the amount of information of the image signal increases, the number of computers 21, 22, and 23 can be changed according to the amount of information to realize a large-screen display with high definition and high resolution according to the amount of information. it can.

[Third Embodiment]
Next, a third embodiment of the present invention will be described.
In the multi-projection systems 1 and 2 according to the first and second embodiments described above, the computer 11, 21, 22, 23 is provided with the timing index signal insertion unit 113, and the timing is applied to the image signal generated by the image generation unit 112. The index signal is inserted, and the timing index signal is transmitted together with the image signal. On the projector 12, 13, 24, 25, 26 side, the timing index signal decoding unit 126 decodes the timing index signal, and based on this, the image display is performed. I was doing control.
In contrast, in the multi-projection system 3 according to the third embodiment, as shown in FIG. 11, the computers 31, 32, 33 and the projectors 34, 35, 36 are connected to the cable 37 separately from the image transmission cable 14. And the timing index signals TIS1 to TIS3 are transmitted independently.

As shown in FIG. 12, the computers 31, 32, and 33 include an image generation unit 112 and an image signal transmission unit 114 as in the first embodiment, but do not include a timing index signal insertion unit. Instead, a timing index signal transmission unit 311 is provided.
The timing index signal transmission unit 311 generates the timing index signals TIS1 to TIS3, and the generated timing index signals TIS1 to TIS3 are transmitted to the cable 37 such as USB connected to the USB port 312 at a predetermined timing. Send.
The projectors 34, 35, 36 include a USB port 341 for connection to the computers 31, 32, 33 in addition to the USB port 129 for communication with the other projectors 34, 35, 36. 33, the timing index signals TIS1 to TIS3 transmitted from the USB port 341 are input and directly transferred to the timing index signal transmission unit 127. The timing index signal transmission unit 127 transmits timing indexes to the other projectors 34, 35, and 36. Signals TIS1 to TIS3 are transmitted.

Such a multi-projection system 3 according to the present embodiment operates based on the flowchart shown in FIG.
When the original image signal is distributed from the server 20 at a predetermined update cycle, the image generation unit 112 of each computer 31, 32, 33 generates divided image signals VIDEO 1 to VIDEO 3 according to the arrangement of the projectors 34, 35, 36. (Procedure S14).
When the divided image signals VIDEO1 to VIDEO3 are generated, the image signal transmission unit 114 of each computer 31, 32, 33 transmits the divided image signals VIDEO1 to VIDEO3 from the video card 115 to the projectors 34, 35, 36 (procedure). S15).

The image signal receiving unit 122 of each projector 34, 35, 36 receives the divided image signals VIDEO 1 to VIDEO 3 input from the video input terminal 121 (step S 16), and writes the divided image signals VIDEO 1 to VIDEO 3 to the frame buffer 123. Perform (step S17).
During this time, the image signal receiving unit 122 monitors the state of writing to the frame buffer 123 and determines whether or not the writing has been completed (step S18).
If it is determined that the writing has been completed, the image signal receiving unit 122 transmits a response signal indicating the completion to the computers 31, 32, 33 from the USB port 341 via the cable 37 (step S19).

When the timing index signal transmission unit 311 of the computers 31, 32, and 33 receives the response signal indicating the completion of writing (step S 20), the projector 31, 35, and 36 receive the frame No. Are generated and transmitted to the projectors 34, 35, and 36 connected (step S21).
When the timing index signal transmission unit 127 of each projector 34, 35, 36 receives the timing index signals TIS1 to TIS3 via the USB port 341 (step S22), the other projectors 34, 35 are the same as in the first embodiment. , 36 for the frame number received by itself. Timing index signals TIS1 to TIS3 are transmitted, and the timing index signal reception monitoring unit 128 receives frame numbers from other projectors 34, 35, and 36. The reception of the timing index signals TIS1 to TIS3 representing is monitored and image display is controlled.

According to the present embodiment, it may be difficult to synchronize the transmission timings of the divided image signals VIDEO1 to VIDEO3 and the timing index signals TIS1 to TIS3, but the timing index signal is not inserted into the image signal. The image signal is not deteriorated.
In addition, since it is not necessary to insert the timing index signal into the image signal in the computers 31, 32, and 33 and to decode the timing index signal in the projectors 34, 35, and 36, the processing in each device can be simplified. The data processing load by 31, 32, 33 and the projectors 34, 35, 36 can be reduced.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described.
In the multi-projection system 3 according to the third embodiment described above, the computers 31, 32, and 33 are connected in a one-to-one correspondence with the corresponding projectors 34, 35, and 36 by a cable 37 such as a USB.
On the other hand, in the multi-projection system 4 according to the fourth embodiment, as shown in FIG. 14, computers 31, 32, and 33 are connected by a LAN cable 41, via a router 42, and further by a LAN cable 43. The difference is that the projectors 34, 35, and 36 are connected to each other.

Timing index signals TIS 1 to TIS 3 transmitted from the computers 31, 32 and 33 are transmitted to the router 42 via the LAN cable 41.
The router 42 distributes the timing index signals TIS1 to TIS3 to the projectors 34, 35 and 36 through the LAN cable 43 while synchronizing.
According to this embodiment, the computers 31, 32, 33 and the projectors 34, 35, 36 are connected to each other via the router 42 via the LAN cable 41 and the LAN cable 43. Therefore, the router 42 It is possible to exchange information between all devices via the network.
In addition, since the mutual devices are connected via the router 42, it is easy to synchronize communication between the devices.

[Modification of Embodiment]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the first embodiment, the timing index signal is inserted into any of the lower bits of the color display data composed of a 16-bit bit string, the pixels in the overlapping area A1, and the corner corner area A2. However, the present invention is not limited to this. For example, if a pixel defect or the like of the light modulation element is known in advance, a timing index signal may be inserted into the color display data corresponding to this pixel defect. In this case, even if a voltage is applied to the pixel, it is not driven, so that the timing index signal can be inserted into all the bit strings of the color display data.

In the first embodiment, when the timing index signal is inserted into the image signal, the timing index signal is inserted into the bit string of the color display data. However, the present invention is not limited to this. The timing index signal may be inserted into the portion.
Furthermore, in the first embodiment, the image signal is transmitted using the DVI standard image transmission cables 14 and 15 as a digital transmission system as the image transmission system of the image signal. The image signal may be transmitted by an analog transmission system using the terminal. In this case, since there is a possibility that a data error occurs in the lower-order bit string of the color display data, it is preferable to perform error correction processing on the color display data using a Reed-Solomon code or the like.
In addition, the specific structure and method for carrying out the present invention may be other structures or the like as long as the object of the present invention can be achieved.

1 is a schematic perspective view showing the structure of an image display system according to a first embodiment of the present invention. The schematic diagram showing the difference in the image update timing between the image display apparatuses in the said embodiment. The schematic diagram for demonstrating the outline of the image display system in the said embodiment. The block diagram showing the structure of the image display system in the said embodiment. The schematic diagram showing the structure of the color display data in the said embodiment. The schematic diagram of the projection image which illustrates the place which inserts the timing index signal in the said embodiment. The flowchart for demonstrating the effect | action of the said embodiment. The flowchart for demonstrating the effect | action of the said embodiment. The schematic diagram showing the structure of the image display system which concerns on 2nd Embodiment of this invention. The block diagram showing the structure of the image display system in the said embodiment. The schematic diagram showing the structure of the image display system which concerns on 3rd Embodiment of this invention. The block diagram showing the structure of the image display system in the said embodiment. The flowchart for demonstrating the effect | action of the said embodiment. The schematic diagram showing the structure of the image display system which concerns on 4th Embodiment of this invention.

Explanation of symbols

  1, 2, 3, 4 ... multi-projection system, 11 ... computer, 12, 13 ... projector, 14, 15 ... image transmission cable, 16 ... cable, 17, 18 ... projected image, 20 ... server, 21, 22, 23 ... Computer, 24, 25, 26 ... Projector, 27 ... Network, 31, 32, 33 ... Computer, 34, 35, 36 ... Projector, 37 ... Cable, 41 ... Cable, 42 ... Router, 43 ... Cable, 111 ... Display Driver 112 112 Image generation unit 113 Timing index signal insertion unit 114 Image signal transmission unit 115 Video card 121 Video input terminal 122 Image signal reception unit 123 Frame buffer 124 Image display , 125 ... Image display controller, 126 ... Timing index Signal signal decoding unit, 127 ... timing index signal transmission unit, 128 ... timing index signal reception monitoring unit, 129 ... USB port, 311 ... timing index signal transmission unit, 312 ... USB port, 341 ... USB port, A1 ... overlapping area , A2 ... corner area, TIS1 to TIS3 ... timing index signal, VIDEO1 to VIDEO3 ... divided image signal

Claims (7)

An image display system comprising an image output device that outputs an image of a frame unit as an image signal, and a plurality of image display devices connected to the image output device,
The plurality of image display devices are connected to each other so as to be capable of bidirectional communication,
The image output device includes:
An image signal generator for generating an image signal for displaying an image on each image display device;
An image signal transmission unit that transmits the image signal generated by the image signal generation unit to each image display device at a predetermined timing; and
A timing index signal generation unit that generates a timing index signal that synchronizes display by each image display device according to a predetermined timing at which the image signal is transmitted;
A timing index signal transmitter that transmits the timing index signal generated by the timing index signal generator to each image display device;
The image display device includes:
An image signal receiving unit for receiving the image signal transmitted from the image signal transmitting unit;
An image signal storage unit for storing the image signal received by the image signal reception unit in units of frames;
An image display unit that displays an image in units of frames based on the image signal stored in the image signal storage unit;
A timing index signal receiving unit that receives the timing index signal transmitted from the timing index signal transmitting unit;
A timing index signal transmitting unit that transmits the timing index signal received by the timing index signal receiving unit to a timing index signal receiving unit of another image display device;
A timing index signal reception monitoring unit that monitors whether or not the timing index signal transmitted from the image output device is received by another image display device;
When the timing index signal reception monitoring unit determines that the timing index signal has been received by all the image display devices, the image display unit receives the frame-based image signal stored in the image signal storage unit. An image display system comprising an image display control unit for displaying an image. The image display system according to claim 1,
The image output device includes:
The timing index signal generation unit inserts the generated timing index signal into the image signal generated by the image signal generation unit,
The timing index signal transmission unit is also used as the image signal transmission unit,
The image display device includes:
A timing index signal decoding unit that decodes and extracts the timing index signal inserted by the timing index signal generation unit;
The image display system, wherein the timing index signal receiving unit is also used as the image signal receiving unit. The image display system according to claim 2,
The image signal is provided to each of a plurality of pixels constituting a frame image, and includes color display data including a plurality of bit strings for causing each pixel to perform color display.
The image display system according to claim 1, wherein the timing index signal is inserted into a predetermined bit string from a least significant bit (LSB) to an upper part of a bit string of color display data of at least one of the pixels. The image display system according to claim 3,
The color display data consists of a bit string of at least 9 bits,
The image display system, wherein the timing index signal is inserted into a bit string lower than 8 bits. The image display system according to any one of claims 2 to 4,
The image display system, wherein the timing index signal is inserted into color display data given to a specific pixel among a plurality of pixels constituting a frame image of the image signal. The image display system according to any one of claims 2 to 5,
The image display device includes a light source, a light modulation device that modulates light emitted from the light source in accordance with an image signal to form an optical image, and a projection device that projects an optical image formed by the light modulation device. And a tiling display in which a part of the projection area of each projector is overlaid,
2. The image display system according to claim 1, wherein the timing index signal is inserted into color display data provided to pixels constituting a frame image of an image signal corresponding to an overlapping area of each projector. An image used in an image display system in which a plurality of image display devices are connected to an image output device that outputs a frame-unit image as an image signal, and the image signals output from the image output device are displayed on each image display device. A display device,
A terminal to which a transmission system capable of bidirectional communication with other image display devices is connected;
An image signal receiving unit for receiving an image signal transmitted from the image signal output device;
An image signal storage unit for storing the image signal received by the image signal reception unit in units of frames;
An image display unit that displays an image in units of frames based on the image signal stored in the image signal storage unit;
A timing index signal receiving unit that receives a timing index signal that is generated by the image output device and that synchronizes display timing of an image signal to be displayed according to a predetermined timing at which the image signal is transmitted;
A timing index signal transmitting unit that transmits the timing index signal received by the timing index signal receiving unit to a timing index signal receiving unit of another image display device;
A timing index signal reception monitoring unit that monitors whether or not the timing index signal transmitted from the image output device is received by another image display device;
When the timing index signal reception monitoring unit determines that the timing index signal has been received by all the image display devices, an image is displayed on the image display unit based on the image signal stored in the image signal storage unit. And an image display control unit.

Images