JP3357212B2 - Multi-screen display system and display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-display system using a plurality of display devices, and more particularly to a multi-display system suitable for displaying signals output from a plurality of signal sources in a desired combination of display devices. The present invention relates to a display system and a display device.

[0002]

2. Description of the Related Art In a multi-screen display system using a plurality of display devices, when a signal output from a signal source is displayed in an enlarged manner, there is a slight difference in image quality such as luminance, contrast, and color between adjacent display devices. This is one of the causes of the deterioration of the image quality of the enlarged and displayed image. In particular, in a display device using a CRT, when a high-luminance image is displayed for a long period of time, the CRT burns in. Therefore, in order to prevent this, luminance control for reducing the luminance and displaying an image is usually performed. However, when such luminance control is performed, when a partially high-luminance image is enlarged and displayed by the multi-screen display system, the display device that enlarges and displays the high-luminance portion reduces the luminance by the luminance control described above. As a result, a partial image is displayed, and as a result, the brightness differs between a display device adjacent to the display device and the brightness of which is not reduced, and the brightness differs between a part of the enlarged display image and another part. There was a problem that would.

On the other hand, Pioneer's 1991 June
"PROJUCTIONCUBE SYSTEM"
In the conventional multi-screen display system and display device described in the catalog of "M", the luminance control systems of the display devices are sequentially cascade-connected via a switch, and a luminance control signal (for example, (A luminance control signal of a display device in which the luminance is controlled so as to reduce the luminance the most) to all the other display devices in the cascade connection. Luminance control is performed as one set to suppress a difference in luminance between adjacent display devices.

FIG. 9 shows such a technique, in which four display devices 1 are arranged four by four in the vertical and horizontal directions to form a 16-screen display system. If these display devices 1 are represented by
As shown by the solid lines, 110, 100, 101, 111,
112, 102, 103, 113, 123, 133, 1
The luminance control systems are cascaded in the order of 32, 122, 121, 131, 130, and 120. In addition, the black circle in each display device 1 represents the switch 2,
By turning off, the cascade connection between the display devices is made or disconnected.

When all the switches 2 are turned on and the luminance control systems of all the display devices 1 are connected in cascade, the luminance control signal a of the display device in which the luminance control is performed so as to reduce the luminance among them is the lowest. It is sent to the brightness control systems of all the display devices 1 and the same brightness control is performed as a whole.

[0006]

The image quality control between adjacent display devices by the cascade connection described above is performed when one image by a signal from one signal source is enlarged and displayed on the entire screen of the multi-screen display system. Although effective, the above-described image quality control cannot effectively exhibit performance when an image based on signals output from a plurality of different signal sources is enlarged and displayed in different regions of a screen of a multi-display system. Hereinafter, this will be described.

[0007] In the following, a combination pattern of display devices that display the same image on a screen of a multi-screen display system is referred to as a display pattern. For example, FIG. 10 shows one display pattern. In this case, the screen of the multi-screen display system is divided into four display areas of the same shape and size, and each display area has four screens of the display device 1. Are combined. FIG. 11 also shows one display pattern. In this case, the screen of the multi-view display system is divided into a central area and 12 peripheral areas surrounding the central area. , A combination of the screens of the four display devices 1, and the twelve peripheral display areas are each composed of one screen of the display device 1.

Now, assuming that a display pattern as shown in FIG. 10 is displayed, in this case, an image based on signals from different signal sources is displayed in each display area. Therefore, four signal sources are used in this case. In this case, brightness control is performed for each image (note that, hereinafter, only brightness control will be described for simplicity, but the same applies to other image quality such as contrast and hue). However, for this purpose, as shown by the solid lines in FIG.
1, 111 are cascaded when switch 2 is on,
Similarly, the display devices 112, 102, 103, 11
3. The display devices 123, 133, 132, and 122, the display devices 121, 131, 130, and 120 are cascade-connected, respectively, and the display devices 111 and 112, the display devices 113 and 123, and the display devices 122 and 121 are connected. The switches 2 are turned off and disconnected. Thus, for example, in the area where the image “A” is enlarged and displayed by the signal output from the same signal source, the four display devices 100 and 11
0, 101, and 111 are set as one set, and the brightness control signals of one of the display devices are used to control the brightness of these four display devices in common. The difference in luminance can be suppressed.

However, displaying the display pattern as shown in FIG. 11 has the following problems.

That is, in this case, as one method, FIG.
As shown in FIG.
Is turned on to cascade-connect the brightness control systems, the switch 2 is turned on between the display devices 122 and 121 to cascade-connect the brightness control systems, and the display devices 101 and 11 are further connected.
1 and the display devices 112 and 102 and the display devices 122 and 1
Switch 2 between the display devices 32 and the display devices 121 and 131, respectively.
There is a method of turning off and cutting. Accordingly, in the display area of the image “A” by the display devices 111, 112, 121, and 122, the brightness can be controlled independently of the other area displaying the image “B”.

However, in the display area where the image "A" is enlarged and displayed, the display devices 111 and 121 and the display devices 112 and 122 cannot be cascaded from the first. And the brightness control of the display devices 112 and 122 are performed independently. As a result, the adjacent display device 11
The difference in luminance between the display devices 1 and 121 and between the adjacent display devices 112 and 122 cannot be suppressed, and a difference in luminance occurs between the upper half and the lower half of the image “A” in FIG.

In this case, since the twelve display devices 1 for displaying the image "B" display the images without enlargement, they are displayed independently of each other, and therefore, the brightness control is performed independently. This does not create a separate problem.

As another method, four display devices 111, 112, 121, and 12 displaying an enlarged image "A" are displayed.
This is a method in which a common brightness control can be performed with one set of two as a set. As shown in FIG. 9, even with the display pattern shown in FIG. The display devices 1 are cascaded to perform common brightness control as a set of these display devices 1. However, according to this method, assuming that the control for lowering the luminance is performed in the display device displaying the image “B”, the luminance control signal “a” indicates that the display device displaying the image “A” is enlarged. Therefore, there is a problem that good brightness control cannot be performed on the image “A”.

As described above, in the conventional image quality control between adjacent display devices by cascade connection, depending on the display pattern, image quality control is performed between adjacent display devices that enlarge and display an image based on a signal output from the same signal source. In some cases, it is not possible to perform this operation, and it becomes impossible to suppress such a difference in image quality between adjacent display devices. In order to prevent this, if it is attempted to perform common image quality control between adjacent display devices, including a display device that displays an image based on signals output from different signal sources, one image information is displayed on the other display image. Inconveniences such as lowering the image quality of the images occur.

In the case of the display pattern shown in FIG. 10, even if the difference in luminance between adjacent display devices can be suppressed, the setting of the switch for turning on / off the cascade connection for this display pattern is as follows. Since each display device is different for each display pattern, the state of the switch of each display device is switched every time the display pattern is changed by the operation means of the multi-screen display system, so that the brightness control corresponding to the set display pattern is performed. There is also a problem that the state cannot be quickly switched and set.

A first object of the present invention is to control the image quality of an arbitrary display pattern by a combination of display devices corresponding to the display pattern, and to enlarge and display an image based on a signal output from the same signal source. Provided is a multi-screen display system and a display device capable of performing image quality control between adjacent display devices and preventing image quality control between adjacent display devices displaying signals output from different signal sources. Is to do.

A second object of the present invention is to provide a multi-screen display system and a display device capable of promptly switching the combination of display devices for performing image quality control accompanying a change in a display pattern.

[0018]

SUMMARY OF THE INVENTION In order to achieve the first object, the present invention relates to an image display apparatus, comprising: a display screen having an image quality such as brightness, contrast, and hue obtained by the same image quality control signal between adjacent display devices in which the sides of the display screen are in contact with each other; Is provided, and the combination of the display devices capable of controlling the image quality by the same image quality control signal can be changed by setting on / off of the switching means.

In order to achieve the second object, according to the present invention, the display device is provided with a storage means, and the setting of the switching means for the display information such as the display number or display name corresponding to the display pattern is previously stored in the storage means. By setting the switching means to the setting stored in the storage means according to the display information, it is possible to quickly change the combination of display devices that perform image quality control by the image quality control signal.

[0020]

According to the present invention, since an image quality control signal is provided between the adjacent display devices, the image quality control by the image quality control signal is performed by the switching means between the adjacent display devices performing image quality control by the image quality control signal. The switching means stops the image quality control by the image quality control signal between the adjacent display devices which are activated and do not perform the image quality control by the image quality control signal, so that the image quality control signal is transmitted in a desired combination of the adjacent display devices. Image quality control can be performed. That is, in the multi-screen display system, the image quality control by the image quality control signal can be performed in a desired combination of the adjacent display devices regardless of the display pattern. Accordingly, when signals output from a plurality of signal sources are enlarged and displayed in a desired combination of the adjacent display devices, image quality control by the image quality control signal is performed between the adjacent display devices that enlarge and display signals output from the same signal source. And the image quality control by the image quality control signal is not performed between the adjacent display devices that display signals output from different signal sources, and the signals output from the same signal source are enlarged and displayed. The difference in image quality between the adjacent display devices can be suppressed, and the image quality of the enlarged display, that is, the image quality of the multi-screen display system can be improved.

Further, according to the present invention, the setting of the switching means is previously stored in the storage means for the display information corresponding to the display pattern.
The switching means can be set simultaneously in all the display devices, and the combination of display devices for performing image quality control by the image quality control signal can be changed quickly.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a multi-screen display system according to the present invention.
It is assumed that a 16-screen display system arranged in 4 planes × horizontal direction is configured.

In FIG. 1, each display device 1 has a luminance control system connected in the horizontal and vertical directions, and connection between adjacent display devices is turned on or off in accordance with the state of the switch 2. I do.

FIG. 2 is a block diagram showing one embodiment of the display device according to the present invention used in the multi-display system shown in FIG. 1, wherein 2 is a switch, 2a to 2d are switch elements, and 3 is an enlargement process. Circuit, 4 a luminance detection circuit, 5 a luminance control circuit, 6 a signal processing circuit, 7 a drive circuit, 8 a CRT, 9 a controller, 10 a nonvolatile memory, 11
Denotes a remote control light receiving unit, 12 denotes an input terminal, and 13a to 13d denote signal lines.

In FIG. 1, although not shown, there are four signal sources, one of which is selected and input from the input terminal 12. The switch 2 has four switch elements 2a to
2d, which is connected to the input / output terminal of the luminance control circuit 5 and is turned on and off by the controller 9. These switch elements 2a to 2d are respectively connected to similar switch elements of different adjacent display devices via signal lines 13a to 13d capable of bidirectional transmission.

The input video signal b from the input terminal 12 is supplied to the enlargement processing circuit 3, and when the image is enlarged and displayed like the image "A" in FIGS. When the image is not enlarged and displayed as in the image "B" of FIG. The output video signal c of the enlargement processing circuit 3 is supplied to the luminance detection circuit 4 and the signal processing circuit 6. The luminance detection circuit 4 detects the luminance of the video signal c and outputs a luminance detection signal d. The luminance detection signal d is supplied to the luminance control circuit 5 together with the luminance control signal a from another display device selected by the switch 2, and the reference luminance signal e is generated based on the luminance detection signal d. In the signal processing circuit 6, the luminance of the video signal c is controlled based on the reference luminance signal e, and the driving circuit 7 is controlled in accordance with the output video signal f.
Drives the CRT 8.

In this way, an image having a predetermined luminance corresponding to the reference luminance signal e is displayed on the screen of the brown area 8.

Here, when the image is a color display, three sets of the driving circuit 7 and the CRT 8 are usually used for the red signal, the green signal, and the blue signal. For simplicity, only one set is shown.

FIG. 3 is a block diagram showing a specific example of the luminance control circuit 5 in FIG.
Is a buffer, and portions corresponding to those in FIG. 2 are denoted by the same reference numerals.

In the figure, a comparison circuit 14 selects a signal indicating the higher luminance among the luminance detection signal d supplied from the luminance detection circuit 4 of FIG. 2 and the luminance control signal a from the switch 2, The reference luminance signal e is supplied to the signal processing circuit 6 (FIG. 2). When the luminance detection signal d has a higher level than the luminance control signal a supplied from the switch 2 and indicates high luminance, the luminance detection signal d becomes the reference luminance signal e.
However, the buffer 15 sends this reference luminance signal e as a luminance control signal a to the luminance control circuit of another display device via the switch 2 and the signal line 13.

Taking the display device 111 in FIG. 1 as an example, four display devices 101, 110, 1 adjacent thereto are shown.
A connection relationship of a brightness control system as shown in FIG. Therefore, if the switch elements provided with the reference numerals in these display devices are turned on, these five display devices 111, 101, 110, 121,
In 112, the brightness control systems are connected to each other, and at least these are commonly controlled by the same brightness control signal.

Therefore, when the display pattern shown in FIG. 10 is displayed in this embodiment, the controller 9 performs the enlargement processing by the display information supplied from the remote controller (not shown) via the light receiving section 11 in FIG. The circuit 3 is controlled, and the enlargement processing circuit 3 enlarges a quarter portion of the video signal b, that is, a quarter portion corresponding to this portion of the image represented by the video signal b, four times vertically and horizontally. As described above. For example, regarding the display device 100 in FIG. 10, the enlargement processing circuit 3 enlarges the portion of the input video signal b corresponding to the upper left quarter of the image represented by it.

The state of each switch 2 is set so that the display device 1 to which the input video signal is supplied from the same signal source uses the same luminance control signal a. Thereby, as shown in FIG. 5, a luminance control system is connected between the four display devices 1 that enlarge and display the same image, as shown by a solid line, and between the adjacent display devices 1 that display other images, As indicated by the broken line, the brightness control system is disconnected. For example, in the case of the five display devices shown in FIG. 4, the switch elements 2a and 2b of the display device 111, the switch element 2c of the display device 101, and the switch element 2d of the display device 110 are on, but The switch elements 2c and 2d, the switch element 2a of the display device 121, and the switch element 2b of the display device 112 are turned off.

Therefore, common brightness control is performed by the same brightness control signal a between adjacent display devices that enlarge and display an image based on a video signal from the same signal source, and the difference in brightness between these adjacent display devices is obtained. In addition, the image quality of all the enlarged and displayed images is improved without being affected by luminance control from an adjacent display device that displays an image based on video signals from different signal sources.

When displaying the display pattern shown in FIG. 11, the controller 9 sets the enlargement processing circuit 3 so as to provide a predetermined display, and as shown by a solid line in FIG. The connection of the luminance control signal a is turned on between the adjacent display devices that enlarge and display the image based on the input video signal b from the source, and the image based on the input video signal from the different signal source is enlarged and displayed as shown by the broken line in FIG. The state of the switch 2 of each display device 1 is set so that the connection of the luminance control signal a is turned off between adjacent display devices.

Referring to the five display devices shown in FIG. 4 as an example, the switch elements 2c and 2d of the display device 111, the switch element 2a of the display device 121, and the switch element 2b of the display device 112 are on. Switch elements 2a and 2b of device 111 and switch element 2c of display device 101
And the switch element 2d of the display device 110 is turned off.

As a result, similarly to the case shown in FIG. 5, the brightness control signal a is commonly used between adjacent display devices for enlarging and displaying an image based on the video signal b from the same signal source. The difference in luminance between the devices is suppressed, and the influence of the luminance control signal a of the adjacent display device that enlarges and displays an image based on an input video signal from a different signal source is eliminated, so that the image quality of the enlarged display image is greatly improved. become.

In the same manner, in an arbitrary display pattern, the connection of the brightness control system is turned on between the adjacent display devices that enlarge and display an image based on the video signal from the same signal source among the adjacent display devices, and By setting the state of the switch 2 of each display device 1 so that the connection of the brightness control system is turned off between the adjacent display devices displaying the image based on the video signal from the source, the video signal from the same signal source is set. Adjacent display devices on which an image is enlarged and displayed are in the same set, and common brightness control is performed only by the brightness control signal a for these. Therefore, there is no difference in luminance between adjacent display devices that enlarge and display an image based on a video signal from the same signal source, and the image quality of the enlarged display image is greatly improved.

When the display pattern shown in FIG. 10 is displayed, it is sufficient that common brightness control by the brightness control signal a can be performed between adjacent display devices that enlarge and display an image based on a video signal from the same signal source. , The connection of the brightness control system between the adjacent display devices as shown in FIG. 7 may be turned on or off, and even when the display pattern shown in FIG. 11 is displayed, as shown in FIG. Although not a display, the connection of the brightness control system may be turned on between a plurality of display devices each displaying an image based on a video signal from the same signal source.

In this embodiment, the connection of the luminance control signal a between adjacent display devices is set to ON or OFF by the switch 2 so that common luminance control by the luminance control signal a can be performed in a desired combination of the display devices 1. Can do it. Therefore, at least, the connection of the brightness control system between the adjacent display devices that enlarges and displays the image based on the video signal from the same signal source is turned on, and the brightness control system between the display devices that displays the image based on the video signals from different signal sources is turned on. By setting the state of the switch 2 of each display device 1 so as to turn off the connection, the difference in luminance between adjacent display devices that enlarges and displays an image based on a video signal from the same signal source is suppressed, and The image quality of the displayed image can be improved.

In FIG. 2, the state of the switch 2 to be set is different for each display pattern in each display device. Therefore, if the state of the switch 2 is reset for each display device by operating the operation means such as a remote controller every time the display pattern is changed, it takes an extremely long time for this setting, and promptly It becomes difficult to change the display pattern.

Therefore, in this embodiment, information for designating the state of the switch 2 for each display pattern (hereinafter referred to as switch setting information) is transmitted from the operating means such as a remote controller via the light receiving unit 11 to the display information. Is stored in the rewritable nonvolatile memory 10 in association with The display information includes a display pattern number and a display pattern name, and the nonvolatile memory 10 stores switch setting information corresponding to the number and name.

When the display pattern is changed by the user or the like to the desired display pattern, display information for the desired display pattern is input by the operating means.
The controller 9 reads the switch setting information corresponding to the input display information from the non-volatile memory 10 and sets the on / off state of the switch 2 according to the switch setting information.

Display information from operating means such as a remote controller at the time of changing the display pattern is simultaneously taken into all display devices forming the multi-display system. This allows
In all the display devices, the states are simultaneously set according to the switch setting information read from the respective non-volatile memories 10, so that the combination of the display devices that perform the common brightness control by the brightness control signal a by a simple operation can be quickly performed. Will be changed to

When the connection of the luminance control signal a is turned off between the adjacent display devices, it goes without saying that the switch 2 of one of the display devices 1 may be set to the off state.

In the above embodiment, the switch 2 is provided on each of the display devices 1 on both sides of the same signal line (for example, in FIG. 4, the display devices 111 and 101 have the same signal line. Switch elements 2a and 2c are provided), one of the display devices may be provided, and one switch element may be provided for each signal line.

Further, although the enlargement of the video signal b has been described with reference to the enlargement processing circuit 3 built in the display device 1 as shown in FIG. 2, the display device 1 does not have the enlargement processing circuit 3 built therein. Obviously, it may be performed by an image enlargement device provided outside the display device 1.

Further, the control data of the enlargement processing circuit 3 is
It may be stored in the nonvolatile memory 10 or may be stored in a separate memory. In any case, according to the designation of the display pattern from the remote controller, the controller 9 reads the corresponding control data and controls the processing of the enlargement processing circuit 3.

[0049]

As described above, according to the multi-screen display system of the present invention, image quality can be controlled by a common image quality control signal in a desired combination of adjacent display devices. That is,
The image quality can be controlled by the image quality control signal in a desired combination of the display devices regardless of the display pattern. Accordingly, when an image based on signals output from a plurality of signal sources is enlarged and displayed in a desired combination of display devices, a common image quality control signal is used between adjacent display devices that enlarge and display an image based on a signal from the same signal source. Adjacent display devices that perform image quality control and display images based on signals from different signal sources can be configured not to perform image quality control using a common image quality control signal, and can perform image control using signals from the same signal source. The image quality of the enlarged display image, that is, the image quality of the multi-screen display system can be greatly improved by suppressing the difference in the image quality of the image between the adjacent display devices that display.

Further, according to the display device of the present invention, the storage means is provided with the storage means which previously stores the state setting information of the switching means corresponding to each display pattern.
When the display pattern is changed, simply by reading out the corresponding state setting information from the storage means, the states according to the desired display patterns of the switching means of all the display devices are simultaneously set, and the change in the display pattern is caused. Combinations of display devices that require image quality control by a common image quality control signal can be quickly changed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing one embodiment of a multi-screen display system according to the present invention.

FIG. 2 is a block diagram showing one embodiment of a display device according to the present invention.

FIG. 3 is a block diagram illustrating a specific example of a luminance control circuit in FIG. 2;

FIG. 4 is a diagram illustrating an example of a connection relationship of a brightness control unit between adjacent display devices in the embodiment illustrated in FIG. 1;

FIG. 5 is an explanatory diagram showing an example of an operation of the multi-screen display system according to the present invention.

FIG. 6 is an explanatory diagram showing another example of the operation of the multi-screen display system according to the present invention.

FIG. 7 is an explanatory diagram showing still another example of the operation of the multi-screen display system according to the present invention.

FIG. 8 is an explanatory diagram showing still another example of the operation of the multi-screen display system according to the present invention.

FIG. 9 is an explanatory diagram showing an example of a conventional multi-screen display system.

FIG. 10 is an explanatory diagram illustrating an example of a display pattern of the multi-screen display system.

FIG. 11 is an explanatory diagram showing another example of the display pattern of the multi-screen display system.

12 is a diagram showing a connection relationship of a luminance control system in the conventional example shown in FIG. 9 for the display pattern shown in FIG. 10;

13 is a diagram showing a connection relationship of a luminance control system in the conventional example shown in FIG. 9 for the display pattern shown in FIG. 11;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Display apparatus 2 Switch 2a-2d Switch element 3 Magnification processing circuit 4 Luminance detection circuit 5 Luminance control circuit 6 Signal processing circuit 7 Drive circuit 8 CRT 9 Controller 10 Memory 11 Remote control light-receiving part 12 Video signal input terminal 13a-13d Signal line 14 Comparison circuit 15 Buffer

Continued on the front page (72) Inventor Atsushi Kaneko 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Hitachi Image Information Systems Co., Ltd. In the system (72) Inventor Masaki Kamata 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture In-house Hitachi Image Information System Co., Ltd. (56) References JP-A-3-1711884 (JP, A) JP-A-3-120583 (JP) JP-A-3-84587 (JP, A) JP-A-2-298171 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 5/68 G09G 5/00

Claims (5)

(57) [Claims] 1. A multi-screen display system in which a plurality of display devices are arranged to form a large screen including a display screen of each of the display devices, and an image of a signal output from a signal source is displayed. There is provided switching means for enabling at least one control of image quality such as brightness, contrast, and hue by the same image quality control signal between adjacent display devices in which the side surfaces of the screen are in contact with each other. A multi-screen display system wherein a combination of the display devices capable of controlling image quality by an image quality control signal can be changed. 2. The image quality control signal according to claim 1, wherein an image based on a signal output from the same signal source is enlarged and displayed in a partial area of the large screen. Wherein the image quality control by the image quality control signal is stopped between adjacent display devices displaying signals output from different signal sources between the adjacent display devices. 3. The storage unit according to claim 1, further comprising a storage unit, wherein a setting of the switching unit for display information such as a display number or a display name is stored in the storage unit in advance, and the storage unit is stored in accordance with the display information. A combination of the adjacent display devices for performing image quality control by the image quality control signal can be promptly changed by setting the switching means to the setting stored in the multi-display display system. 4. A display device for displaying an image based on a signal output from a signal source, wherein the image quality control system controls at least one of image quality information such as luminance, contrast, and hue. And a switching means for activating or stopping an image quality control system based on the image quality control signal. 5. The storage device according to claim 4, further comprising a storage unit, wherein the setting of the switching unit for display information such as a display number or a display name is stored in the storage unit in advance, and the storage unit is stored in accordance with the display information. A display device, wherein the switching means is set to a stored setting.