JPH09185351A - Multiscreen system display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the oneness among cores of multiple images projected on a screen from decreasing owing to variance in characteristics among equipments in the cores. SOLUTION: The cores 71a-71d are equipped with sensors 74, each of which sends photodetection data to a microcomputer 76 according to reflected light from the screen 77. The photodetection data is compared with a specific value stored previously in the microcomputer 76 and control signals are sent on the basis of the comparison result to contrast and (or) luminance control circuits 78 in the cores 71a-71d and a display equipment 73 to eliminate the variance in characteristics among the respective equipments in the cores 71a-71d, thereby improving the quality of the image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-screen display device having a function of adjusting the image quality (contrast, brightness and hue) of an image displayed on a screen.

[0002]

2. Description of the Related Art By arranging a plurality of display devices (for example, a plurality of cathode ray tubes (CRTs)) in contact with each other,
There is a so-called multi-screen type display device (hereinafter, referred to as a multi-screen type display device) that constitutes one large-sized multi screen or displays an image projected from a plurality of display devices on one large screen. In this multi-screen display device, if the image quality of the images obtained from the individual display devices constituting the multi-screen, for example, the contrast, brightness and hue are not substantially equal, the seams between adjacent screens are conspicuous and the image quality deteriorates. There was a problem. Therefore, conventionally, various measures have been implemented to solve this problem. For example, as one of the conventional examples, there is a technique disclosed in Japanese Patent Laid-Open No. 5-150730. Here, for simplification of the description, a multi-screen display device having a configuration similar to the technique disclosed in the above publication will be described with reference to FIGS. 12 to 16.

FIG. 12 is a block diagram showing a brightness adjusting device of a conventional multi-screen display device. In the figure, 1a to 1d are cores each having a projection device (not shown), and 2 is a comparison. Circuits 3a to 3d are reference voltage insertion circuits, and 6 is a comparison circuit for ABL (automatic brightness limit). In this example, a case where four cores are arranged in contact with each other to form a multi-screen as shown in FIG. 13 will be described. That is, the screens of four CRTs are arranged adjacent to each other to form one multi-screen.

In FIG. 12, each of cores 1a-1d provided corresponding to four screens has the same structure. Each of the cores 1a to 1d includes a contrast and / or brightness control circuit 11 and a CRT (cathode ray tube) drive circuit 1
2, a CRT 13, an ABL (automatic brightness limiting) circuit 14, a high voltage generation circuit 15, a beam current detection resistor 17, a power supply voltage (+ B) application terminal 18, and a switch 50. The ABL circuit 14 determines the magnitude of the beam current flowing from the high voltage generation circuit 15 and the like by the beam current detection resistor 17
The control voltage is generated based on the detection result, and this control voltage is applied to the contrast in the core and / or
It is supplied to the brightness control circuit 11. Reference voltage insertion circuit 3a-
3d inputs a reference voltage from the outside through the reference voltage application terminal 16 during the overscan period of the video signal input to the contrast and / or brightness control circuit 11 and inserts it into the overscan period of the video signal. The comparison circuit 2 is
Each of the cores 1a to 1d within the overscan period of the video signal
The reference voltage inserted inside is compared and the comparison result is output. The ABL comparison circuit 6 is the ABL in each of the cores 1a to 1d.
Comparing the ABL control information obtained from the circuit 14 and selecting the core having the maximum beam current value based on the comparison result,
The ABL control information of the selected core is output to each of the cores 1a to 1d to control the operation of the switch 50. In FIG. 12, an arrow pointing from the ABL comparison circuit 6 to the switch 50 indicates a control signal output from the ABL comparison circuit 6 for controlling the operation of the switch 50. Based on this control signal, one of the terminals 50a and 50b is connected to the contrast and / or brightness control circuit 11.

Next, the operation will be described. FIG. 14 is a diagram for explaining the operating characteristics of the ABL circuit 14 in each of the cores 1a to 1d, where the horizontal axis is the beam current Ib and the vertical axis is the control voltage Vcc.
Is shown. In FIG. 14, video signal input terminals 4a to 4d
It is assumed that a predetermined image based on the video signal is displayed on the screen of the CRT 13, which is a display device in each of the cores 1a to 1d, by the video signal input from the. When the average brightness of the screen, that is, the beam current Ib has a value equal to or lower than the predetermined level Ia, the ABL circuit 14 outputs the constant voltage Vcc
Is supplied to the ABL comparison circuit 6. On the other hand, the beam current I
When b is equal to or higher than a predetermined level (Ia in FIG. 14), A
The BL circuit 14 outputs the voltage Vz (Vz = + B−R · Ib) supplied to the ABL circuit 14 at that time to the ABL comparison circuit 6
Output to As a result, the ABL circuit 14 operates to lower the control voltage and lower the average brightness of the screen when the beam current Ib becomes equal to or higher than the predetermined level Ia. A in the other core
The BL circuit 14 also performs the same operation. ABL comparison circuit 6
Is selected by selecting the lowest voltage among the control voltages Vcc output from all the cores 1a to 1d, in other words, the ABL control information (lowest control voltage Vcc) of the core having the maximum beam current Ib value. And sends ABL control information to all other cores.

Here, considering the case where the switches 50 in all the cores 1a to 1d are connected to the terminal 50a side, the core outputting the ABL control information with the highest average brightness is output by itself. Closed loop control is performed according to the ABL control information. However, in other cores, the ABL control information output by itself is not fed back, so that it becomes open loop control. Therefore, variations in the gains of the respective open loops, that is, variations in the contrast and / or the gains of the luminance control circuit 11 and the ABL circuit 14 occur, and variations in the luminance between the images obtained in the respective cores occur.

Conventionally, the variation in gain among the cores is reduced by using the circuit for absorbing the variation in gain, that is, the reference voltage inserting circuits 3a to 3d and the comparison circuit 2.

Next, the operations of the reference voltage inserting circuits 3a to 3d and the comparing circuit 2 which are circuits for absorbing the gain variation will be described. The reference voltage inserting circuits 3a to 3d have the same configuration. FIG. 15 is a block diagram showing the inside of each of the reference voltage inserting circuits 3a to 3d. 16 is a reference voltage applying terminal, 31 is a buffer, 33 is a switch for switching the input to the contrast and / or brightness control circuit 11, Reference numeral 32 denotes a switching pulse (SP) input terminal for controlling the operation of the switch 33. The arrow in the figure indicates that the switch 33 causes the switch 33 to connect to the video signal input terminal 4a side and the reference voltage applying terminal 1 by this switching pulse (SP).
It shows that any of the six sides is connected to the contrast and / or brightness control circuit 11 side. Each core 1
Reference voltage insertion circuit 3a provided for a to 1d
A reference voltage (B / W) having a common voltage value and timing is supplied to the reference voltage application terminal 16 within 3d.

FIG. 16 is a waveform diagram for explaining the principle of the reference voltage inserting operation in the reference voltage inserting circuits 3a to 3d and the contrast and / or brightness control circuit 11 shown in FIG. Indicates the scan period. In the multi-screen display device, the overscan period T is defined to be, for example, about 8% of the scanning period in order to smooth the connection of images displayed between the cores. The reference voltage (B / W) is a signal in which the white level (W) and the black level (B) are alternately switched every 1H (horizontal synchronization) of the video signal. The switching pulse (SP) is a high-level control pulse having a pulse width T in synchronization with the falling edge of the horizontal sync pulse. The switching pulse (SP) controls input of a signal to the contrast and / or brightness control circuit 11. For example, during the overscan period in the first half of the scanning period, the switching pulse (SP) has a cycle T.
Then, the reference voltage (B / W) is applied from the buffer 31. On the other hand, in other periods,
The switching pulse (SP) becomes low level, the switch 33 connects the video signal input terminal 4 to the contrast and / or brightness control circuit 11, and the video signal is input from the video signal input terminal 4. Therefore,
In the first half overscan period of the video signal, the reference voltages of the white level (W) and the black level (B) are alternately inserted into the cores 1a to 1d every 1H of the video signal.

[0010]

Since the conventional multi-screen type display device is configured as described above, the contrast and brightness of the image signal waveform of the image obtained by each core are equal between the cores. It seems that a uniform image can be obtained in the case where the characteristics of the display device incorporated in each core are the same between the cores. If the emission characteristics of the CRT are different from those of the other cores, or if the display device is an LCD projection type projection instead of the CRT, the video signal waveforms with the same gain may be generated in each core due to variations in the characteristics of the light transmittance of the light source and LCD. Even if obtained inside, the contrast and brightness of the image actually displayed on the screen may differ from screen to screen, resulting in poor image quality. There was a problem.

Further, as in the technique disclosed in Japanese Unexamined Patent Publication No. 7-64522, a screen is photographed by one camera, data output from this camera is calculated, and the calculation result is fed back to obtain a video signal. There is also a method of adjusting and controlling the waveform, but in this case adjustment work in a dark room is required to avoid the influence of external light, and it is necessary to separately install the above adjustment camera to shoot the display screen. Although it can be implemented by the manufacturer, it is difficult for the user to implement.

The present invention has been made to solve the above problems, and in a multi-screen type display device, even if the characteristics of the devices in each core vary,
An object of the present invention is to obtain a multi-screen display device capable of displaying images having the same image quality, that is, contrast, brightness and hue.

[0013]

According to another aspect of the present invention, there is provided a multi-screen type display device comprising a control means for controlling an image quality adjusting operation for changing the image quality of an image projected by a plurality of image display means. Further, each of the plurality of image display means has a detection means for receiving the reflected light from the screen and transmitting the received light data to the control means. The control means generates a control signal for controlling the image quality adjustment operation based on the value of the received light reception data and transmits the control signal to the plurality of image display means, and the plurality of image display means causes the image quality of the image based on the control signal. To improve the image quality of the image displayed on the screen by eliminating variations in the characteristics of the plurality of image display means.

According to a second aspect of the present invention, in the multi-screen display device, the control means compares the received light data from the detection means with a predetermined value, and the control signal generated based on the comparison result is the contrast / luminance control means. Directly to the screen to change the contrast and brightness of the image displayed on the screen to eliminate variations in the characteristics of the image display means, particularly variations in the characteristics of the display means for contrast and brightness and the characteristics of the detection means. The image quality of the image is improved.

According to another aspect of the present invention, there is provided a multi-screen type display device comprising image quality adjustment reference signal generating means for generating an image quality adjustment reference signal, and the image quality adjustment reference signal is generated under the control of the control means to generate a contrast / luminance. By transmitting the generated image quality adjustment reference signal to the control means, a separate image quality adjustment reference signal generation means is not required outside the multi-screen display device.

In the multi-screen type display device according to the invention described in claim 4, when the power is turned on to start the operation of the plurality of image display means, a power-on signal for notifying the power supply is transmitted to the control means. To be done. The control means transmits the control signal to the plurality of image display means after receiving the power-on signal, and further instructs the image quality adjustment reference signal generating means to generate the image quality adjustment reference signal, so that the control means is automatically activated at the same time when the power is turned on. This is to instruct the start of the image quality adjustment operation.

In the multi-screen type display device according to the present invention, the control means compares the received light data transmitted from the detection means with a predetermined value, and displays the control signal generated based on the comparison result. To the image displayed on the screen by changing the hue of the image displayed on the screen to eliminate variations in the characteristics of the image display means, particularly variations due to the characteristics relating to the hue of the display means and the characteristics of the detection means. Is to improve.

In the multi-screen type display device according to the present invention, the control means compares the received light data from the detection means with a predetermined value, and the control signal generated based on the comparison result is subjected to contrast / luminance control. Means for directly transmitting to the means and the display means to change the contrast, brightness and hue of the image quality of the image displayed on the screen to eliminate variations in the characteristics of the image display means, especially variations due to the characteristics of the display means and the detection means, This improves the image quality of the image displayed on the screen.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. 1 is a block diagram showing a multi-screen display device according to Embodiment 1 of the present invention. In the figure, 71a to 71d are cores (image display means), 77 is one screen, and each core 71a to 7 is shown.
The image projected from 1d is displayed. Reference numeral 76 denotes a microcomputer (control means, hereinafter abbreviated as a microcomputer),
Reference numeral 87 is a microcomputer operation unit that sends an instruction to the microcomputer 76. The multi-screen display device has cores 71a to 7a.
1d, a screen 77, a microcomputer 76 and a microcomputer operating section 87.

Further, 73 is a display device (display means) such as CRT projection type projection or LCD (liquid crystal device) projection type projection, 72 is a display device driving circuit (driving means) for driving the display device 73, and 74 is Receives the reflected light from the screen 77, R (red), G (green), B
A color sensor (detection means) for converting a current corresponding to each color component of (blue) into a voltage and outputting the voltage, 75 is an A / D converter,
Reference numeral 78 is a contrast and / or brightness control circuit (contrast / brightness control means). In this way, each core 7
1a to 71d are the display device drive circuit 72 and the display device 7
3, a color sensor 74, an A / D converter 75, and a contrast and / or brightness control circuit 78.

The color sensor 74 is installed for each core 71a to 71d of the multi-screen display device. When the color sensor 74 is installed between the display device 73 and the screen 77, the color sensor 74 directly receives the projection light projected from the display device 73 to the screen 77, and the shadow of the color sensor 74 is projected on the screen 77. Therefore, in order to avoid this, the color sensor 74 is arranged on the screen 77 at a position where it does not become a shadow. In addition, individual display devices 73
Since the characteristics of the color sensor 74 and the color sensor 74 generally vary, the individual color sensor
4 is measured and the measured data is preset as a predetermined value in the microcomputer 76, for example, in a memory (not shown).

As described above, in the multi-screen type display device according to the first embodiment, the operator operates the microcomputer operating section 87 to send an image quality adjustment mode start signal (START) for instructing the start of the image quality adjustment operation to the microcomputer. The image is sent from the operation unit 87 to the microcomputer 76, and the microcomputer 76 receives the image quality adjustment mode start signal (START) and sends a control signal for image quality adjustment operation to the contrast and / or brightness control circuit 78 to send a screen 77. The contrast and brightness, which are the image quality of the image displayed above, are changed, thereby eliminating the variations due to the characteristics relating to the contrast and brightness of the display device 73 and the characteristics of the color sensor 74, and unifying the contrast and brightness of the image. Let In the first embodiment, the core in the multi-screen display device is assumed to be composed of four cores 71a to 71d as shown in FIG. 2 for simplification of description.

Next, the operation will be described. The video signals input from the video signal input terminals 4a to 4d are controlled in the contrast and / or brightness control circuit 78 and are input to the display device 73 via the display device drive circuit 72, and are displayed on the screen 77 from the display device 73. An image corresponding to this image signal is projected toward the display, and as a result, a predetermined image is displayed on the clean 77. The other cores 71b to 71d perform the same operation. In this case, due to variations in the characteristics of the contrast and / or brightness control circuit 78, the display device drive circuit 72, and the display device 73 in each of the cores 71a to 71d, for example, let white be displayed on the entire screen of the display device 73. In that case, there are screens with different brightness and white screen with a little reddish color, and the uniformity of contrast and brightness is lacking as a whole. In order to solve this, in the multi-screen display device according to the first embodiment, the color sensor 74
Is used to perform an image quality adjustment operation for eliminating variations in contrast and brightness as the image quality of the image displayed on the screen 77.

For example, first, an image signal as an image quality adjustment reference signal is set to an all white signal. In this case, for example, the video signals R (red), G (green) and B (blue) are set to the high level. Video signal input terminal 4a
The all-white video signal, which is the image quality adjustment reference signal, is input into the cores 71a to 71d via the to 4d and displayed on the screen 77. The reflected light from the screen 77 is applied to each core 71.
The color sensor 74 provided in a to 71d receives the light.
The received light data transmitted from the color sensor 74 is A /
The D converter 75 receives the signal, A / D-converts it, and transmits the converted light reception signal to the microcomputer 76. Here, the A / D-converted received light data transmitted from the color sensor 74 to the A / D converter 75 is composed of R (red), G (green), and B (blue) components. The microcomputer 76 receives the A / D converted received light data. The operator operates the microcomputer operation unit 87
By operating, the microcomputer operation unit 87 generates an adjustment mode start signal (START) for starting the adjustment of contrast and brightness, and this adjustment mode start signal (START) is sent to the microcomputer 76. Upon receipt of this start signal, the microcomputer 76 sends a control signal to the contrast and / or brightness control circuit 78 in each of the cores 71a to 71d.

FIG. 3 is a flow chart for explaining the control of the image quality adjustment operation by the microcomputer 76, and the control operation of the microcomputer 76 will be described below using this flow chart. In the following description of the image quality adjustment operation, the image quality adjustment operation using the R (red) component of the light reception signal supplied from the color sensor 74 will be described.

In the image quality adjusting operation of the core 71a, when the operator operates the microcomputer operating section 87, the microcomputer operating section 87 generates an adjustment mode start signal (START) and sends it to the microcomputer 76. When the microcomputer 76 receives the adjustment mode start signal (START), the image quality adjustment operation in the image quality adjustment mode starts (step ST
79). Color sensor 7 reflects the light reflected from the screen 77.
4 receives light. The received reflected light is transmitted from the color sensor 74 to the A / D converter 75 as received light data, and this received light data is A / D converted by the A / D converter 75. The A / D conversion data R ₁ obtained is used for the A / D converter 75.
From the microcomputer 76 to the microcomputer 76, and the microcomputer 76 receives the A / D conversion data R ₁ and takes it in the inside (step ST8).
0).

The microcomputer 76 compares the fetched A / D converted data R ₁ with a predetermined value R ₀ stored in advance in the memory, and if the A / D converted data R ₁ is equal to the predetermined value R _0. If it is a value, that is, if R ₁ = R ₀ (step ST 81), the value of the control signal R _G output from the microcomputer 76 to the contrast and / or brightness control circuit 78 is not changed (step ST 84). Then, the operation of the adjustment mode of the microcomputer 76 ends (step ST85). The above-mentioned value R ₀ is the R component value of the display device 73 that displays white optimally when R ₁ = R ₀ when it is desired to display white on the screen. This R ₀ is measured in advance. The measurement data to which the characteristic variation of the color sensor 74 is added is stored as a predetermined value in a memory (not shown) in the microcomputer 76.

The comparison in step ST81 is that R ₁ = R ₀
If not, it is compared whether or not R ₁ is smaller than R ₀ (step ST82), and if R ₁ <R ₀ , it is transmitted to the contrast and / or brightness control circuit 78 in order to greatly change the value of R _1. The value of the control signal R _G being set is set to a large value (step ST86), the process returns to step ST80, and the A / D conversion data R ₁ transmitted from the A / D converter 75 to the microcomputer 76 is stored in the microcomputer 76. Re-execute the operation for capturing into. This repeating operation is performed in step ST.
In the comparison of R ₁ and R ₀ at 81, this is repeated until R ₁ = R ₀ .

On the other hand, as a result of the comparison in step ST82,
When R ₁ > R ₀ , the value of the control signal R _G transmitted from the microcomputer 76 to the contrast and / or brightness control circuit 78 is set to a small value (step ST83), and then the process returns to step ST80 and A / D The operation of fetching the A / D conversion data R ₁ transmitted from the converter 75 to the microcomputer 76 into the microcomputer 76 is executed again. This repetitive operation is repeated until R ₁ = R ₀ in the comparison between R ₁ and R ₀ in step ST81.

Further, adjustments are made in the same procedure for the other G (green) and B (blue) components which are received light signal components. Further, the image quality adjusting operation similar to the above is executed in parallel for the other cores 71b to 71d.

As described above, the adjustment mode start signal (STAR
T) is generated, the microcomputer 76 receives the adjustment mode start signal (START) (step ST79),
An all-white image signal was used as an image quality adjustment reference signal to display an all-white image on the entire screen 77, after which adjustments for all the cores 71a to 71d were completed, and a white screen with the same contrast and brightness could be displayed on the entire screen. By the way, the image quality adjustment operation ends.

In the above description, an image quality adjustment operation is performed by displaying an all-white image on the screen 77. However, this image quality adjustment operation is an operation for eliminating the variation due to the characteristics of the devices in each of the cores 71a to 71d. Once the variation due to the characteristics of the device is eliminated by the image quality adjustment operation,
It is not necessary to display an image of R (red), G (green), B (blue), etc. other than white on the screen 77 and execute the image quality adjustment operation for each color again.
Even when different images are displayed between d, it is possible to display the image having the optimum image quality. In the above description, the image quality adjustment operation is performed by displaying all white on the screen 77, but the image quality adjustment operation may be performed by displaying another color. In this case, a predetermined value corresponding to the color used for the image quality adjusting operation and added with variations in the characteristics of the color sensor 74 is stored in a memory (not shown) in the microcomputer 76.

As described above, according to the first embodiment, the characteristic data of the color sensor 74 in each of the cores 71a to 71d is measured in advance, and the measured data is stored in the memory in the microcomputer 76 as a predetermined value. Since the contrast and brightness image quality adjustment operations are controlled by each core 71a
A multi-screen display device capable of eliminating variations due to the characteristics of the display device 73 regarding the contrast / luminance and the characteristics of the color sensor 74 between 71 d and 71 d and having no variations in the contrast and luminance as the image quality of the image projected on the screen. Obtainable. Further, this image quality adjusting operation does not require special equipment and can be easily executed by the manufacturer and the user. Furthermore, since the above-mentioned predetermined value is stored in the memory in the microcomputer 76, it is easy to change the predetermined value and it is possible to flexibly deal with various applications.

Embodiment 2 FIG. 4 is a block diagram showing a multi-screen type display device according to Embodiment 2 of the present invention. In the figure, 89 is an image quality adjustment reference signal generating circuit (image quality adjustment reference signal generating means), and 88a to 88d.
Is an analog switch. Note that the same components as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted. In the multi-screen display device according to the first embodiment shown in FIG. 1, the image quality adjustment as a video signal corresponding to the color used for the image quality adjustment operation from the outside of the multi-screen display device is performed via the video signal input terminals 4a to 4d. Although a reference signal, for example, a white image quality adjustment reference signal is input into each of the cores 71a to 71d to perform an image quality adjustment operation of contrast and brightness, in the second embodiment,
An image quality adjustment reference signal generation circuit 89 is provided in the multi-screen type display device, and the image quality adjustment reference signal generation circuit 89 itself generates the image quality adjustment reference signal under the control of the microcomputer 76, and the analog image switches 88a to 88d are used. The image quality adjustment reference signal thus generated is transmitted to each of the cores 71a to 71d, and the image quality adjustment operation of the contrast and the brightness is performed.

Next, the operation will be described. FIG. 5 is a flowchart showing the image quality adjustment operation in the multi-screen display device according to the second embodiment. An adjustment mode start signal (START) for starting an image quality adjustment operation of contrast and brightness is generated by the microcomputer operation unit 87 by the operation of the operator, and this adjustment mode start signal (START) is transmitted to the microcomputer 76 (step ST79). When the microcomputer 76 receives the adjustment mode start signal (START), it issues an instruction to generate an image quality adjustment reference signal which is a video signal for displaying a reference color used for the image quality adjustment operation, for example, an all white image on the screen 77. The microcomputer 76 transmits to the image quality adjustment reference signal generation circuit 89 (step ST90), and at the same time, the analog switches 88a to 88d are set to the image quality adjustment reference signals 89a to 8d.
Switch to the 9d side (step ST91). As a result, the contrast and / or brightness control circuit 78 in each of the cores 71a to 71d is controlled by the image quality adjustment reference signal generation circuit 89.
Connected to Then, a white video signal, which is an image quality adjustment reference signal, is output from the image quality adjustment reference signal generation circuit 89 to each core 71.
a to 71d, and adjustments similar to the image quality adjustment operation described in the first embodiment are executed in steps ST80 to 84 and step ST86.

When the image quality adjusting operation is completed, the microcomputer 76
Instructs the analog switches 88a to 88d to switch to the video signal input terminals 4a to 4d side (step ST92), and at the same time stops the generation and transmission of the image quality adjustment reference signal to the image quality adjustment reference signal generation circuit 89. A command to perform is sent (step ST93). This allows
The image quality adjustment reference signal generation circuit 89 stops the generation and transmission of the adjustment signal, while the analog switches 88a-88d.
Is switched to the video signal input terminals 4a to 4d side, the video signal input terminals 4a to 4d and the respective cores 71a to 71d are connected, and the image quality adjustment operation ends (step ST85).

In the image quality adjusting operation in the multi-screen display device according to the second embodiment, the microcomputer 76 issues a command to the image quality adjusting reference signal generating circuit 89 to generate and transmit the image quality adjusting reference signal. However, for example, the image quality adjustment reference signal generation circuit 89 always generates and transmits the image quality adjustment reference signal, and the microcomputer 76 instructs only the analog switches 88a to 88d to switch when instructing the start of the image quality adjustment operation. You may In this case, in the flowchart of FIG. 5, the operations of step ST90 and step ST93 for instructing the image quality adjustment reference signal generating circuit 89 from the microcomputer 76 are not necessary.

As described above, according to the second embodiment, since the video signal which is the image quality adjustment reference signal is generated inside the multi-screen display device, the effect of the first embodiment can be obtained. The image quality can be adjusted without separately installing an image quality adjustment reference signal generator or the like outside.

Embodiment 3 FIG. 6 is a block diagram showing a multi-screen display device according to a third embodiment of the present invention, in which 94 is a core 71a to 71d.
Is a power-on signal terminal for transmitting to the microcomputer 76 a power-on signal as ON / OFF information indicating that the power has been turned on. The same components as those shown in FIGS. 1 and 4 are designated by the same reference numerals, and the duplicate description will be omitted. In the third embodiment, the power source for displaying images on the cores 71a to 71d side and the power source of the microcomputer 76 are set to separate systems. When the power of the cores 71a to 71d is turned on,
For example, the cores 71a to 71d generate a power-on signal indicating that the power is turned on (or may be generated by another component), and the power-on signal is sent to the microcomputer 76 via the power-on signal terminal 94. Upon transmission, the microcomputer 76 receives the power-on signal and automatically starts the image quality adjustment operation of the image projected on the screen 77.

Next, the operation will be described. FIG. 7 is a flowchart showing the image quality adjustment operation in the multi-screen display device according to the third embodiment. When the power of the cores 71a to 71d is turned on by the operator's operation, a power-on signal notifying that the power has been turned on is transmitted to the microcomputer 76 via the power-on signal terminal 94. Upon receiving the power-on signal (step ST94), the microcomputer 76 operates the image quality adjustment mode start signal (STAR) from the microcomputer operating section 87 by the operation of the operator.
Similarly to the case where T) is transmitted to the microcomputer 76, the image quality adjusting operation of the contrast and the brightness of the image displayed on the screen 77 is automatically started (step ST7).
9). Subsequent image quality adjustment operations are steps ST90 to 93 and steps ST80 to 86 described in the second embodiment.
Is the same as the operation of.

As described above, according to the third embodiment, when the cores 71a to 71d are powered on, for example, the cores 71a to 71d generate a power-on signal and the cores 71a to 71d generate the power-on signal via the power-on signal terminal 94. A power-on signal is transmitted to the microcomputer 76. As a result, similarly to the case where the operator manually operates the microcomputer operating section 87 to instruct the microcomputer 76 to start the image quality adjustment operation, the microcomputer 76 automatically starts the image quality adjustment operation upon receiving the power-on signal. . Therefore,
A multi-screen display device capable of automatically starting the image quality adjusting operation when the power of the cores 71a to 71d is turned on, and optionally starting the image quality adjusting operation by the operation of the operator. be able to.

Embodiment 4 FIG. 8 is a block diagram showing a multi-screen display device according to Embodiment 4 of the present invention. In the figure, 171a to 171d are cores, and 120 is provided for each core 171a to 171d.
This is an operational amplifier circuit that calculates the received light data transmitted from the color sensor 74, amplifies the received light data, and transmits the amplified amplified received light data to the A / D converter 75. Note that the same components as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted. In the fourth embodiment, the microcomputer 76 is directly connected to the display device 73 in each of the cores 171a to 171d, and is not connected to the contrast and / or brightness control circuit 78 as in the first embodiment. Not not. The microcomputer 76 transmits a control signal for the image quality adjustment operation to the display device 73 to change the hue of the image displayed on the screen 77, thereby varying the hue of the display device 73 and the characteristics of the color sensor 74. To unify the hue.

FIG. 9 is a block diagram showing the concept of the optical transmission path of the G (green) video signal inside the display device 73 when the display device 73 is an LCD projection projection type unit. In the figure, 95 is a dichroic. Mirror cyan, 96 is dichroic mirror green, 97 is a phase plate, 98 is an incident side polarization plate, 99 is an LCD, and 100 is an emission side polarization plate. The G (green) in the display device 73
In addition to the optical transmission path of the video signal, R (red) video signal and B
(Blue) Has an optical transmission path for video signals, but R (red)
The optical transmission path of the video signal and the B (blue) video signal is the same as the configuration of the optical transmission path of the G (green) video signal, except that the filters are the dichroic mirror cyan 95 and the dichroic mirror green 96 which are filters. Is.
Note that, in the optical transmission path of the B (blue) video signal, the change in the hue of the B (blue) video signal is generally R (red) or G (green).
The phase plate control system 101 does not control the phase plate 97 because it is smaller than the change in the hue of the video signal.

Therefore, the optical transmission path of the G (green) video signal will be described here as a representative, whereby variations due to the characteristics relating to the hue of the display device 73 and the characteristics of the color sensor 74 can be eliminated and the hue of the image can be obtained. A description will be given to improve the image quality.

As described above, the light transmission path of the G (green) video signal in the display device 73 is the dichroic mirror cyan 95, the dichroic mirror green 96,
The phase plate 97, the incident side polarization plate 98, the LCD 99 and the emission side polarization plate 100. The G (green) video signal passes through the optical transmission path in the display device 73 and is projected on the screen 77 as G (green) light. Reference numeral 101 denotes a phase plate control system, the operation of which is controlled by a control signal transmitted from the microcomputer 76. When the display device 73 receives the control signal transmitted from the microcomputer 76, the phase plate control system 101 mechanically operates the phase plate 97 based on the control signal to change the hue.

In the case of the R (red) video signal, the phase plate control system 101 mechanically controls the phase plate 97 in the optical transmission path as in the case of the G (green) video signal. On the other hand, in the optical transmission path for the B (blue) video signal, the phase plate 97 is not controlled by the phase plate control system 101 for the reason described above.

The operational amplifier circuit 120 includes a color sensor 74.
Receives the received light data transmitted from R (red), G
The operational amplifier circuit 12 calculates the ratio of each component of (green) and B (blue).
The calculation result is transmitted to the A / D converter 75. The received light data, which is the calculation result transmitted from the A / D converter 75 to the microcomputer 76, is G ₁ / B and R ₁ / G ₁ . Where R ₁ is the R (red) component value of the received light data, G
₁ is a G (green) component value, and B is a B (blue) component value. These calculation results are compared with predetermined values (G ₀ / B, R ₀ / G _0, etc.), which are stored in advance in a memory (not shown) in the microcomputer 76 and to which variations in the characteristics of the color sensor 74 are added. It These predetermined values will be described later. In the description of the fourth embodiment, since the phase plate 97 does not control the B (blue) video signal, the B of the received light data is not controlled.
The (blue) component value is simply expressed as B.

Next, the operation will be described. Adjustment mode for inputting all G (green) video signals to the video signal input terminals 4a to 4d and operating the microcomputer operating section 87 by the operator to instruct the microcomputer operating section 87 to start the image quality adjusting operation of the hue. A start signal (START) is generated. This adjustment mode start signal (START) is sent to the microcomputer 7
6 is transmitted. From the microcomputer 76 to the cores 171a to 17
The transmission operation until the control signal G _C is fed back into 1d and transmitted is the same as that in the first embodiment, but in the fourth embodiment, the control signal G _C is transmitted from the microcomputer 7
6 to the display device 73.

FIG. 10 is a flow chart for explaining the control operation of the microcomputer 76. First, the video signal input terminal 4
All G (green) video signals are input to a to 4d. The operator operates the microcomputer operating section 87, whereby the microcomputer operating section 87 issues an adjustment mode start signal (ST) for instructing to start the image quality adjusting operation of the hue of the image on the screen 77.
ART) is generated (step ST79), and this adjustment mode start signal is transmitted to the microcomputer 76.

From the microcomputer 76 to the cores 171a to 171d
The operation in which the control signal G _C is fed back to is similar to that in the first embodiment. The microcomputer 76 receives the G ₁ / B data as the received light data transmitted from the A / D converter 75 and takes it in (step ST121).
A predetermined value G stored in the memory (not shown) of the microcomputer 76 which is obtained by measuring the received received light data G ₁ / B in advance.
₀ / B (step ST122), and when both are equal, the control signal G _C transmitted from the microcomputer 76 to the phase plate control system 101 in the display device 73 is transmitted without changing the value (step ST126). The image quality adjustment operation ends (step ST86).

On the other hand, if the comparison results in step ST122 indicate that they are not equal, the next step ST12
Then, the procedure proceeds to step 3 to compare whether G ₁ / B is smaller than G ₀ / B (step ST123). If G ₁ / B <G ₀ / B, the value of the control signal G _C is changed significantly (step S
T125), the microcomputer 76 is controlled in step ST121.
Return to

As a result of the comparison in step ST123, G ₁
When / B> G ₀ / B, the value of the control signal G _C is changed small (step ST124), and then step ST12.
Return to 1. These operations are performed with G ₁ /
Repeated until B = G ₀ / B.

Next, all R signals are input to the video signal input terminals 4a-4d.
(Red) Input the video signal, and the operator
Is operated to generate an adjustment mode start signal (START) for instructing the microcomputer operation unit 87 to start the image quality adjustment operation of the hue (step ST127).
This adjustment mode start signal (START) is transmitted to the microcomputer 76.

From the microcomputer 76 to the cores 171a to 171d
The control signal R _C (which is a control signal corresponding to the control signal G _C used when the above-mentioned all G (green) video signals are input) is fed back to and transmitted to the embodiment. It is similar to the case of 1. Microcomputer 76 is A
R ₁ as the received light data transmitted from the A / D converter 75
/ G ₁ data is received and taken in (step ST1
28). The received light reception data R ₁ / G ₁ is compared with a predetermined value R ₀ / G ₀ previously measured and stored in the memory (not shown) of the microcomputer 76 (step ST129),
If both are the same, the control signal R _C directly transmitted from the microcomputer 76 to the phase plate control system 101 in the display device 73 is continuously transmitted without changing the value (step ST133), and the image quality adjustment operation ends (step ST86). ).

On the other hand, when the comparison result in step ST129 is not equal, the next step ST13
The process proceeds to 0 and it is compared whether or not the received light data R ₁ / G ₁ is smaller than a predetermined value R ₀ / G ₀ . R ₁ / G ₁ <R ₀ / G ₀
In the case of, the value of the control signal _RC is largely changed (step ST132), and the control of the microcomputer 76 is performed in step ST12.
Return to 8.

The result of the comparison in step ST130 is R ₁
When / G ₁ > R ₀ / G ₀ , the value of the control signal R _C is changed to a small value (step ST131), and then step ST
Return to 128. These operations are repeated until both values become equal (R ₁ / G ₁ = R ₀ / G ₀ ) in step ST129.

In each of the above steps, as the values of the control signals G _C , R _C increase, the G ₁ / B value, R
_{The 1} / G ₁ value increases, and conversely, the G ₁ / B value and the R ₁ / G ₁ value decrease as the values of the control signals G _C and R _C decrease. In the case of an R (red) video signal, the G ₁ value is the reference for calculation, so
(Green) After finishing the image quality adjustment operation using the video signal, R
(Red) Performs image quality adjustment using the video signal.

As described above, according to the fourth embodiment, the reflected light from the screen 77 is transmitted to the cores 171a to 171d.
The color sensor 74 provided inside receives the light and A / D
The value of the received light data from the converter 75 is compared with a predetermined value (for example, the predetermined values G ₀ / B and R ₀ / G ₀ used in the above description) stored in advance in the microcomputer 76, and the comparison result is a control signal. As a feedback to the phase plate control system 101 in the display device 73, thereby eliminating variations due to the characteristics relating to the hue of the display device 73 and the characteristics of the color sensor 74 and unifying the hue of the image projected on the screen. it can. Further, this image quality adjusting operation does not require special equipment and can be easily executed by the manufacturer and the user. Furthermore, since the above-mentioned predetermined value is stored in the memory in the microcomputer 76, it is easy to change and it is possible to flexibly deal with various uses.

Embodiment 5. FIG. 11 is a block diagram showing a multi-screen display device according to Embodiment 5 of the present invention. In the figure, 271a to 271d are cores. It should be noted that the first embodiment shown in FIG.
The same components as those of the fourth embodiment shown in FIG. In the fifth embodiment, the contrast and / or brightness control circuit 78 in each of the cores 271a to 271d and the display device 73 and the microcomputer 76 are directly connected to each other, and the contrast and brightness of the image displayed on the screen 77 are adjusted. Further, the microcomputer 76 generates a control signal used for the image quality adjusting operation of the hue, and transmits the control signal to the contrast and / or 444 brightness control circuit 78 and the display device 73, and the display device 7
3 and the characteristics of the color sensor 74 are eliminated, thereby unifying the contrast, brightness, and hue of the image displayed on the screen 77. In other words, the multi-screen display device of the fifth embodiment is a combination of the first and fourth embodiments.

Next, the operation will be described. The basic image quality adjusting operation of the fifth embodiment is similar to the image quality adjusting operation described in the first and fourth embodiments, but the control signal for the image quality adjusting operation transmitted from the microcomputer 76 is the contrast. And / or the brightness control circuit 78 as well as to the display device 73, so that each core 271a
It is possible to eliminate variations due to the characteristics of each device within 271d, and as a result, the contrast, brightness, and hue of the image displayed on the screen are unified.

First, a control signal for the hue image quality adjustment operation is transmitted from the microcomputer 76 to the display device 73 to execute the hue image quality adjustment operation, and then the control signals for the contrast and brightness image quality adjustment operations are applied to the contrast and brightness. (Or)
It is transmitted to the brightness control circuit 78 and the image quality adjusting operation of the contrast and brightness is executed. As a result, the hue, contrast, and brightness of the image displayed on the screen 77 are unified, and the image quality of the image is improved. Further, it is also possible to combine the configuration of the fifth embodiment with the configurations of the second and third embodiments, and it is possible for those skilled in the art to carry out the invention by considering the description of each of the above-described embodiments. Then, the explanation is omitted.

As described above, according to the fifth embodiment, the microcomputer 76 determines the control signal used for the image quality adjustment operation based on the received light data obtained by the color sensor 74 receiving the reflected light from the screen 77. Since the control signal is generated and transmitted to the contrast and / or brightness control circuit 78 and the display device 73, the variation due to the characteristics of each device in each core 271a to 271d can be eliminated and displayed on the screen. Image contrast, brightness, and hue can be unified. Further, this image quality adjusting operation does not require special equipment and can be easily executed by the manufacturer side and the user side. Furthermore, since the above-mentioned predetermined value is stored in the memory in the microcomputer 76, it is easy to change and it is possible to flexibly deal with various uses.

[0063]

As described above, according to the first aspect of the invention, the detection means receives the reflected light reflected by the screen, and the control means displays the image on the screen based on the received light data obtained. Since it is configured to generate the control signal used for the image quality adjustment operation of and to transmit the control signal to the plurality of image display means, it is possible to eliminate the variation due to the characteristics of each device in the plurality of image display means, and to make it uniform. There is an effect that an image of good quality can be displayed.

According to the second aspect of the present invention, the control means compares the received light data from the detection means with a predetermined value stored in advance in the control means, and controls the contrast / luminance control means based on the comparison result. Since the signal is directly transmitted to eliminate the variations in the characteristics of the image display means, especially the variations in the characteristics of the display means such as the contrast / luminance and the characteristics of the detection means, it is possible to obtain uniform and good contrast and luminance. There is an effect that an image with high image quality can be obtained. Furthermore, since the above-mentioned predetermined value is stored in the memory in the control means, it is easy to change, and there is an effect that it can flexibly cope with various uses.

According to the third aspect of the invention, the image quality adjustment reference signal generating means generates the image quality adjustment reference signal under the control of the control means and transmits the image quality adjustment reference signal to the contrast / luminance control means. With this configuration, there is an effect that the image quality can be adjusted without separately providing the image quality adjustment reference signal generating means outside the multi-screen display device.

According to the fourth aspect of the invention, the image display means transmits a power-on signal for informing the power-on for starting the operation to the control means, and the control means performs a plurality of image display means based on the power-on signal. Since the control signal for controlling the image quality adjustment operation is transmitted to the image quality adjustment reference signal generation means and the image quality adjustment reference signal generation means generates the image quality adjustment reference signal, it is possible to automatically start the image quality adjustment operation when the power is turned on. is there.

According to the fifth aspect of the invention, the control means compares the received light data from the detection means with a predetermined value, and directly transmits a control signal obtained based on the comparison result to the display means to cause the image display means to operate. Since it is configured to eliminate the characteristic variation, particularly the characteristic relating to the hue of the display means and the characteristic of the detection means, there is an effect that an image having a uniform and good image quality without the hue variation can be displayed on the screen. Further, since the above-mentioned predetermined value is stored in the memory in the control means, it is easy to change, and there is an effect that it can flexibly cope with various uses.

According to the invention described in claim 6, the control means compares the received light data from the detection means with a predetermined value, and directly transmits a control signal based on the comparison result to both the contrast / luminance control means and the display means. Since it is configured to eliminate the variation in the characteristics of the image display means, particularly the variation in the characteristics of the display means and the detection means, the contrast,
There is an effect that an image having a uniform and good image quality without variations in brightness and hue can be displayed on the screen. Also,
Since the above-mentioned predetermined value is stored in the memory in the control means, it can be easily changed, and there is an effect that it can flexibly cope with various uses.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a multi-screen display device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a configuration of a multi-screen of the multi-screen display device of FIG.

FIG. 3 is a flowchart of control of image quality adjustment operation by a microcomputer of the multi-screen display device of FIG.

FIG. 4 is a block diagram showing a multi-screen display device according to a second embodiment of the present invention.

5 is a flowchart of control of an image quality adjustment operation by a microcomputer of the multi-screen display device of FIG.

FIG. 6 is a block diagram showing a multi-screen display device according to a third embodiment of the present invention.

7 is a flowchart of control of an image quality adjusting operation by a microcomputer of the multi-screen display device of FIG.

FIG. 8 is a block diagram showing a multi-screen display device according to a fourth embodiment of the present invention.

FIG. 9 is a block diagram of an optical transmission path of a G signal of an LCD projection projection type unit as a display device.

10 is a flowchart of control of an image quality adjustment operation by a microcomputer of the multi-screen display device of FIG.

FIG. 11 is a block diagram showing a multi-screen display device according to a fifth embodiment of the present invention.

FIG. 12 is a block diagram showing a conventional multi-screen display device.

FIG. 13 is a diagram showing a configuration of a multi-screen of the conventional multi-screen display device of FIG.

FIG. 14 is a diagram illustrating operating characteristics of the ABL circuit in each core of the multi-screen display device in FIG.

15 is a block diagram showing each reference voltage insertion circuit of the conventional multi-screen display device of FIG.

16 is a waveform diagram illustrating the principle of reference voltage insertion operation in the reference voltage insertion circuit and the contrast and / or brightness control circuit of FIG.

[Explanation of symbols]

71a to 71d, 171a to 171d, 271a to 27
1d core (image display means), 72 display device drive circuit (drive means), 73 display device (display means), 74 color sensor (detection means), 76 microcomputer (control means), 77 screen, 78 contrast and / or ) Luminance control circuit (contrast / luminance control means), 89 Image quality adjustment reference signal generation circuit (image quality adjustment reference signal generation means).

Claims (6)

[Claims] 1. A plurality of image display means for generating and projecting an image, a screen for displaying the image projected from the plurality of image display means, and a screen provided for each of the plurality of image display means. Detecting means for receiving the reflected light of the received light and generating received light data based on the received reflected light, and for controlling the image quality adjusting operation of the image projected from the plurality of image display means by receiving the received light data. A multi-screen type display device comprising: a control means for generating a control signal based on the value of the received light data and transmitting the generated control signal to the plurality of image display means. 2. Each of the plurality of image display means is for detecting means, display means for projecting an image on a screen, and receiving a control signal transmitted from the control means to change the contrast and brightness of the image. Contrast / luminance control means for generating control data based on the control signal, and drive means for receiving the control data and driving the display means based on the control data, the control means including light reception data The multi-screen display device according to claim 1, wherein the control signal is compared with a predetermined value, the control signal is generated based on the comparison result, and the generated control signal is transmitted to the contrast / luminance control means. 3. An image quality adjustment reference signal generation means for generating an image quality adjustment reference signal used in an image quality adjustment operation under the instruction of the control means and transmitting the generated image quality adjustment reference signal to the contrast / luminance control means. The multi-screen display device according to claim 2, further comprising: 4. When the power is turned on to start the operation of the plurality of image display means, the plurality of image display means generate a power-on signal indicating that the power is turned on, and the control means receives the power-on signal. Then, the control signal is transmitted to the plurality of image display means and the image quality adjustment reference signal generation means is instructed to generate the image quality adjustment reference signal used in the image quality adjustment operation, and the image quality adjustment reference signal generation means generates the generated image quality adjustment reference signal. 4. The multi-screen display device according to claim 3, wherein the image quality adjustment reference signal is transmitted to the contrast / luminance control means. 5. Each of the plurality of image display means includes a detection means, a contrast / brightness control means for generating control data for changing the contrast and brightness of the image, and a control means for projecting the image on a screen. A display unit that receives the control signal transmitted from the display unit and changes the hue of the image based on the control signal; and a drive unit that receives the control data and drives the display unit based on the control data. The control means receives the light reception data transmitted from the detection means, compares the light reception data with a predetermined value, generates the control signal based on the comparison result, and transmits the control signal to the display means. The multi-screen display device according to claim 1, wherein the display device is a multi-screen display device. 6. Each of the plurality of image display means receives a detection means and control data for receiving a control signal transmitted from the control means and changing the contrast and brightness of the image based on the received control signal. Contrast / luminance control means for generating, display means for projecting the image on a screen, receiving the control signal transmitted from the control means, and changing the hue of the image based on the control signal, and the control data. And a drive unit that drives the display unit based on the control data, and the control unit receives the light reception data transmitted from the detection unit and compares the light reception data with a predetermined value to obtain a comparison result. The control signal is generated based on the control signal of the image by transmitting the control signal to the contrast / luminance control means and the display means. The multi-screen display device according to claim 1, wherein the last, the brightness, and the hue are changed.