JP3246187B2 - Display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to analog R, G, B
The present invention relates to a display device of a (red, green, blue) drive type, and more particularly to a display device improved for an application requiring accurate color reproduction.

[0002]

2. Description of the Related Art A conventional analog R, G, B drive display device has no means for confirming the level difference between the respective color signals of the R, G, B signal sources.

[0003]

If there is a level difference between the respective color signals of the R, G and B signal sources, even if the white balance on the display device side is accurate, the R and G signals of the signal sources are obtained. Since there is no means for confirming or correcting the white balance error caused by the level difference between B and B, there is a problem in accurate color reproducibility.

[0004] In view of the above, the present invention considers that if there is a level difference between the respective color signals of the R, G, and B signal sources, the level difference is converted into a luminance difference of the screen, and each of them is displayed on the same screen of the display device. It is an object of the present invention to provide means for easily confirming or correcting the level difference between the respective color signals of the R, G, and B signal sources by dividing and displaying the luminance of the R, G, and B signals.

[0005]

In order to solve the above-mentioned problem, the display device with R, G, and B signal level confirmation and correction functions according to the present invention has a red display device according to the present invention. , Green and blue signal lines, three first input, two second and third input signal switches inserted into the three signal lines, respectively, and the above-mentioned respective signals in synchronization with a horizontal synchronizing signal or a vertical synchronizing signal. A switching signal generator for controlling an input signal switching device;
The inputs of the output input signal switch are connected to red, green, and blue input signal lines, respectively, and the second three inputs 1
The input of the output input signal switch is connected to the red, green, and blue input signal lines, respectively, and the input of the third three-input one-output input signal switch is also the red, green, and blue input, respectively. It is configured to be connected to a signal line.

[0006] In the display device according to the second aspect,
One three-input one-output input signal switch and two switches inserted into the red, green, and blue signal lines, and the input signal switch in synchronization with a horizontal synchronization signal or a vertical synchronization signal. And a switching signal generator for controlling the input and output of the three-input one-output input signal switch, respectively.

[0007] In the display device according to the third aspect,
The first, inserted in each of the red, green and blue signal lines
A second and a third three-input one-output input signal switch, a switching signal generator for controlling each of the input signal switches in synchronization with a horizontal synchronization signal or a vertical synchronization signal, and three variable switches; It has a gain-type amplifier, and the inputs of the first three-input one-output input signal switch are red, green, and
The input of the second three-input one-output input signal switch connected to the blue input signal line is red, green,
The inputs of the third three-input one-output input signal switch connected to the blue input signal line are also red,
Each of the signal switches is connected to green and blue input signal lines, and the output of each signal switch is connected to each of the variable gain amplifiers.

[0008]

According to the present invention, the R, G, and B signals which may include a level error are switched by a switching signal synchronized with a horizontal synchronizing signal or a vertical synchronizing signal according to the above-described configuration, and the red, green, and red signals are displayed on the same screen in a time-division manner. The luminance component driven by the signal, the luminance component driven by the green signal, and the luminance component driven by the blue signal are displayed at the same time, and the level difference of the source signal can be easily determined based on the comparison of the luminance levels. This has the effect that the detection can be confirmed or the level difference between the source signals can be easily corrected.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A display device according to an embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing an embodiment of a display apparatus having an R, G, and B signal level confirmation function according to the first aspect of the present invention.

In FIG. 1, reference numeral 1 denotes a red signal input terminal;
Is a green signal input terminal, 3 is a blue signal input terminal, and 4 is a synchronization signal input terminal. Reference numeral 5 denotes a three-input one-output input signal switch inserted in the red signal line, reference numeral 6 denotes a three-input one-output input signal switch inserted in the green signal line, and reference numeral 7 denotes a blue signal line. This is a three-input one-output input signal switch. Reference numeral 8 denotes a switching signal generator that switches an input switch in synchronization with a horizontal synchronization signal, 9 denotes a red signal amplification circuit, 10 denotes a green signal amplification circuit,
Reference numeral 11 denotes a blue signal amplifier circuit, and reference numeral 12 denotes a display element such as a cathode ray tube or liquid crystal. 13 is 8
Is a switch for switching the switching signal generation device from the normal mode to the confirmation mode.

The operation of the display device having the R, G, and B signal level confirmation function configured as described above will be described below.

First, in a normal state, the mode control switch 13 is released, and the switching signal generator 8 controls the three-input one-output input signal switches 5, 6, and 7 in accordance with the mode shown in FIG. The red signal externally connected to the input terminal 1 passes through the signal switch 5 and the red signal amplifier circuit 9 and is connected to the red signal input of the display element 12.
A green signal externally connected to the input terminal 2 passes through the signal switch 6 and the green signal amplifying circuit 10 and passes through the display element 12.
The blue signal connected from the outside to the input terminal 3 is connected to the blue signal input of the display element 12 through the signal switch 7 and the blue signal amplifier circuit 11. In this state, the present display device is no different from a normal display device.

Here, when the mode control switch 13 is short-circuited, the switching signal generator 8 shifts to the confirmation mode, and according to the mode shown in FIG. 2, the three input signals inserted into the red signal line within one horizontal period. The outputs of a one-output input signal switch 5, a three-input one-output input signal switch 6 inserted in the green signal line, and a three-input one-output input signal switch 7 inserted in the blue signal line An output signal for switching at high speed is generated so as to output screen 1, screen 2, and screen 3.

Thus, in the period of one third from before the horizontal scanning corresponding to the screen 1, the red signal externally connected to the input terminal 1 is output from the signal switch 5, the signal switch 6, and the signal switch 6. The signals are distributed by the switch 7 and are simultaneously input to the red signal input, the green signal input, and the blue signal input of the display element 12 through the red signal amplifier circuit 9, the green signal amplifier circuit 10, and the blue signal amplifier circuit 11, respectively. Thus, a black-and-white screen driven by a red signal is displayed in the 1/3 period from before the horizontal scanning. In addition, in a central 1/3 period of the horizontal scanning corresponding to the screen 2, a green signal externally connected to the input terminal 2 is distributed by the signal switch 5, the signal switch 6, and the signal switch 7. , A red signal amplifier circuit 9 and a green signal amplifier circuit 1, respectively.
0, passes through the blue signal amplifying circuit 11 and is simultaneously input to the red signal input, the green signal input, and the blue signal input of the display element 12, and the black-and-white screen driven by the green signal during the central 1/3 period of horizontal scanning. Will be displayed.

In the period of one third from the end of the horizontal scanning corresponding to the screen 3, the blue signal externally connected to the input terminal 3 is output from the signal switch 5, the signal switch 6, and the signal switch 6. , And are simultaneously input to the red signal input, the green signal input, and the blue signal input of the display element 12 through the red signal amplifier circuit 9, the green signal amplifier circuit 10, and the blue signal amplifier circuit 11, respectively. In the 1/3 period after the horizontal scanning, a black-and-white screen driven by a blue signal is displayed. As a result, according to the levels of the red signal externally connected to the input terminal 1, the green signal externally connected to the input terminal 2, and the blue signal externally connected to the input terminal 3, The black and white luminance signal appears as shown in FIG.

As described above, according to this embodiment, the timing of the switching signal is switched in synchronization with the horizontal synchronizing signal, so that the red signal is driven to the left one-third of the screen and the level of the red signal is changed. A black-and-white luminance signal having a luminance proportional to the green signal is driven to a green signal at the center of the screen, and a black-and-white luminance signal having a luminance proportional to the green signal level is outputted to the right third of the screen. In addition to being driven to a blue signal, a black-and-white luminance signal having a luminance proportional to the blue signal level is simultaneously obtained in one screen, and the level difference between the R, G, and B source signals is determined by the brightness of the luminance signal. The difference will be clearly visible.

Although the switching signal generator 8 is switched in synchronization with the horizontal synchronization signal in the embodiment of FIG. 1, the switching signal generator 8 may be switched in synchronization with the vertical synchronization signal. In this case, it goes without saying that the direction in which the confirmation screen is divided and displayed by the respective primary color signals is from left to right and up and down.

(Embodiment 2) FIG. 4 is a block diagram showing an embodiment of a display apparatus having a function of confirming R, G, and B signal levels according to claim 2 of the present invention.

In FIG. 4, reference numeral 14 denotes an input terminal for a red signal;
15 is a green signal input terminal, 16 is a blue signal input terminal, 1
Reference numeral 7 denotes a synchronization signal input terminal. Reference numeral 18 denotes a three-input one-output input signal switch inserted in the red signal line, 19 denotes a switch inserted in the green signal line, and 20 denotes a switch inserted in the green signal line.
Is a switch inserted in the green signal line, and 21
Is a switching signal generator for switching an input switch in synchronization with a horizontal synchronizing signal, 22 is a red signal amplifying circuit, 23 is a green signal amplifying circuit, 24 is a blue signal amplifying circuit, 25 is a CRT or liquid crystal display display. Element. Reference numeral 26 denotes a switch for switching the 21 switching signal generators from the normal mode to the confirmation mode.

The operation of the display device having the R, G, and B signal level confirmation function configured as described above will be described below.

First, the mode control switch 26 is normally released, and the switching signal generator 21 controls the three-input one-output input signal switch 18 and the switches 19 and 20 in accordance with the mode shown in FIG. The red signal externally connected to the input terminal 14 passes through the signal switch 18 and the red signal amplifying circuit 22 and passes through the display element 2.
The green signal connected to the red signal input 5 and the external terminal connected to the input terminal 15 passes through the green signal amplifier circuit 19 and the green signal input of the display element 25.
The blue signal externally connected to 6 passes through the switch 20 and the blue signal amplifying circuit 24 and is connected to the blue signal input of the display element 25. In this state, the present display device is no different from a normal display device.

Here, when the mode control switch 26 is short-circuited, the switching signal generator 21 shifts to the confirmation mode,
According to the mode shown in FIG. 5, the output of the three-input one-output input signal switch 18 inserted into the red signal line within one horizontal period becomes the output of screen 1, screen 2, and screen 3. Then, an output signal that switches at high speed is generated. In this checking mode, the switch 19 inserted in the green signal line and the switch 20 inserted in the blue signal line are open as is clear from FIG. 5, and the green signal amplifier circuit 23 and the blue signal No signal is supplied to the signal amplification circuit 24, and the display element 25 does not emit light other than red.

Thus, in the period of １ ／ from before the horizontal scanning corresponding to the screen 1, the red signal externally connected to the input terminal 1 is supplied from the signal switch 18 to the red signal amplifying circuit 22. , And is input to the red signal input of the display element 12, so that a red screen driven by the red signal is displayed in the 1/3 period from before the horizontal scanning. Also, the center 1/3 of the horizontal scan corresponding to screen 2
In the period, the green signal externally connected to the input terminal 15 passes through the red signal amplification circuit 22 from the signal switch 18 and is input to the red signal input of the display element 25, and the horizontal scanning is performed. In the central 1/3 period, a red screen driven by a green signal is displayed.
Then, during a period of １ ／ from the end of the horizontal scanning corresponding to the screen 3, the blue signal externally connected to the input terminal 16 is transmitted from the signal switch 18 to the red signal amplifier 22.
, And is input to the red signal input of the display element 25, and the red screen driven by the blue signal is displayed in the 1/3 period from the end of the horizontal scanning. As a result, according to the levels of the red signal externally connected to the input terminal 14, the green signal externally connected to the input terminal 15, and the blue signal externally connected to the input terminal 16, The red light and dark signals appear as shown in FIG.

As described above, according to this embodiment, the timing of the switching signal is switched in synchronization with the horizontal synchronizing signal, so that the red signal is driven to the left one-third of the screen and the level of the red signal is changed. A red luminance signal having a luminance proportional to the green signal is driven to a green signal in the center 1/3 of the screen, and a red luminance signal having a luminance proportional to the green signal level is provided to the right 1/3 of the screen. While being driven to a blue signal, a red luminance signal having a luminance proportional to the blue signal level is obtained simultaneously in one screen.
The level difference between the R, G, and B source signals can be clearly recognized as the brightness difference of the red signal. Further, as compared with the first embodiment, only one input signal switch having three inputs and one output is required, and the circuit itself of the switch signal generator can be simplified.

Although the switching signal generator 21 is switched in synchronization with the horizontal synchronization signal in the embodiment shown in FIG. 4, the switching signal generator 21 may be switched in synchronization with the vertical synchronization signal. In this case, it goes without saying that the direction in which the confirmation screen is divided and displayed by the respective primary color signals is from left to right and up and down.

In the embodiment shown in FIG. 4, the input signal switch 18 having three inputs and one output is inserted in the red signal line, but may be inserted in the green or blue signal line. In this case, it is natural that the actual confirmation screen is changed from a screen of only red to a screen of green or blue.

(Embodiment 3) FIG. 6 is a block diagram showing an embodiment of a display device having an R, G, B signal level correcting function according to the third aspect of the present invention.

In FIG. 6, 27 is an input terminal for a red signal,
28 is a green signal input terminal, 29 is a blue signal input terminal, 3
Reference numeral 0 denotes an input terminal for a synchronization signal. Reference numeral 31 denotes a three-input one-output input signal switch inserted in the red signal line, reference numeral 32 denotes a three-input one-output input signal switch inserted in the green signal line, and reference numeral 33 denotes a blue signal line. And a three-input one-output input signal switch.
Is a switching signal generator that switches the input switch in synchronization with the horizontal synchronization signal, 35 is a red signal variable gain amplifier circuit, 36 is a green signal variable gain amplifier circuit, 37 is a blue signal variable gain amplifier circuit, Reference numeral 38 denotes a display device such as a cathode ray tube or a liquid crystal. Also, 39
Is a switch for switching the 34 switching signal generators from the normal mode to the confirmation mode.

The operation of the display device having the R, G, and B signal level confirmation function configured as described above will be described below. First, in a normal state, the mode control switch 39 is released, and the switching signal generator 34
The input signal switches 31, 32, and 33 of three inputs and one output are controlled in accordance with the mode shown in FIG. 2, and the red signal externally connected to the input terminal 27 is changed by the signal switch 31 and the red signal variable. The green signal connected to the red signal input of the display element 38 through the gain type amplifier circuit 35 and externally connected to the input terminal 28 passes through the signal switch 32 and the variable gain type amplifier circuit 36 for the green signal. The blue signal connected to the green signal input of the display element 38 and externally connected to the input terminal 29 passes through the signal switch 33 and the variable gain amplifier 37 for the blue signal, and is connected to the blue signal input of the display element 38. ing.

In this state, the present display device is no different from a normal display device. Here, when the mode control switch 39 is short-circuited, the switching signal generator 34 shifts to the confirmation mode, and in accordance with the mode shown in FIG. 2, the three-input one-output signal inserted into the red signal line within one horizontal period. The output of the input signal switch 31, the three-input one-output input signal switch 32 inserted in the green signal line, and the three-input one-output input signal switch 33 inserted in the blue signal line are output from the screen 1. An output signal for switching at high speed is generated so as to output the screen 2 and the screen 3. Thus, in the period of １ ／ from before the horizontal scanning corresponding to the screen 1, the red signal externally connected to the input terminal 27 is output from the signal switch 31, the signal switch 32, and the signal switch 33. And passes through a red signal variable gain amplifier circuit 35, a green signal variable gain amplifier circuit 36, and a blue signal variable gain amplifier circuit 37, respectively, and a red signal input, a green signal input, and a blue signal input of the display element 38. At the same time, and a black-and-white screen driven by a red signal is displayed in the 1/3 period from before the horizontal scanning.

The center 1 of horizontal scanning corresponding to the screen 2
In the period of / 3, the green signal externally connected to the input terminal 28 is distributed by the signal switch 31, the signal switch 32, and the signal switch 33, and the variable gain amplifier circuit 35 for the red signal, The signal passes through the green signal variable gain amplifier circuit 36 and the blue signal variable gain amplifier circuit 37, and is simultaneously input to the red signal input, the green signal input, and the blue signal input of the display element 38.
In the / 3 period, a black-and-white screen driven by a green signal is displayed. Then, during a period of １ ／ from the end of the horizontal scanning corresponding to the screen 3, the blue signal externally connected to the input terminal 29 is output from the signal switch 31,
The signal is distributed by a signal switch 32 and a signal switch 33, passes through a red signal variable gain type amplifier circuit 35, a green signal variable gain type amplifier circuit 36, and a blue signal variable gain type amplifier circuit 37, respectively. The signal input, the green signal input, and the blue signal input are simultaneously input, and a black-and-white screen driven by the red signal is displayed in the 1/3 period from the end of the horizontal scanning.

As a result, a red signal externally connected to the input terminal 27, a green signal externally connected to the input terminal 28, and a blue signal externally connected to the input terminal 29 are displayed on the screen. A black and white luminance signal corresponding to the level appears as shown in FIG.

As described above, according to this embodiment, the timing of the switching signal is switched in synchronization with the horizontal synchronizing signal, so that the red signal is driven to the left one-third of the screen and the red signal level is reduced. A black-and-white luminance signal having a proportional luminance is driven to a green signal in the center 1/3 of the screen, and a black-and-white luminance signal having a luminance proportional to the green signal level is converted to a blue signal in the right 1/3 of the screen. When driven, a black-and-white luminance signal having a luminance proportional to the blue signal level is obtained simultaneously in one screen.
The level difference between the R, G, and B source signals can be clearly recognized as the brightness difference between the luminance signals. And even 3
The gains of the variable gain amplifier circuit of red signal 5, the variable gain amplifier circuit of green signal 36, and the variable gain amplifier circuit of blue signal 37 are appropriately changed so that there is no luminance difference on the screen. By doing so, the level difference between the signal sources can be corrected, and an accurate white balance can be obtained.

Although the switching signal generator 34 is switched in synchronization with the horizontal synchronization signal in the embodiment of FIG. 6, the switching signal generator 34 may be switched in synchronization with the vertical synchronization signal. In this case, it goes without saying that the direction in which the confirmation screen is divided and displayed by the respective primary color signals is from left to right and up and down.

[0036]

As described above, the display device with R, G, and B signal level confirmation functions and the display device with R, G, and B signal level correction functions of the present invention can have R, G, and B levels that can include level errors. Each signal is switched by a switching signal synchronized with the horizontal synchronization signal or the vertical synchronization signal,
The luminance component driven by the red signal, the luminance component driven by the green signal, and the luminance component driven by the blue signal are simultaneously displayed on the same screen in a time-divisional manner, and the brightness levels are compared. Therefore, the level difference of the source signal can be easily visually confirmed, or the level difference of the source signal can be easily corrected, and the practical effect is large.

[Brief description of the drawings]

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

FIG. 2 is an output state diagram of a switch in FIG. 1;

FIG. 3 is a display example of a screen and a luminance signal diagram according to the present invention.

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

FIG. 5 is an output state diagram of a screen switch and a switch in FIG. 4;

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

[Explanation of symbols]

1, 2, 3, 4, 14, 15, 16, 17, 27, 2
8, 29, 30 input terminal 5, 6, 7, 18, 31, 32, 33 input signal switch 8, 21, 34 switching signal generator 9, 10, 11, 22, 23, 24 amplifying circuit 12, 25, 38 Display element 13, 26, 39 Switch for switching from normal mode to confirmation mode 19, 20 Switch 35, 36, 37 Variable gain amplifier circuit

Claims (3)

(57) [Claims] 1. A three-input / one-output three-input / one-output signal switch inserted into each of red, green, and blue signal lines, and a horizontal synchronizing signal or a vertical synchronizing signal. A switching signal generator for controlling each of the input signal switches in synchronization with each other, and the three 3-input / 1-output input signals
The first, second and third outputs of the switch are red,
The display elements connected to the green and blue signal input terminals
Generated signal output from switching signal generator in normal mode
Mode switch that switches according to
And input terminals of the first three-input one-output input signal switch are connected to red, green, and blue input signal lines, respectively. input red respectively, green, is connected to an input signal line of blue, the third three-input 1 input also each red output of the input signal switch, green, is connected to an input signal line of blue, the Changeover switch to confirm mode
When switched, horizontal or vertical sync period
Is divided into three for the first, second, and third periods, and the switching is performed.
The first period is controlled by a switching signal from the signal generator.
Between the first three-input one-output input signal switcher
These red signals are the red, green, and blue signal input terminals of the display element.
And the second three inputs during the second period.
The green signal from the input signal switch with 1 output
Input to the red, green, and blue signal input terminals of the
In the third period, the input signal of the third three inputs and one output is turned off.
The blue signal from the switching device is used for red, green, and blue of the display element.
All signals are input to the signal input terminal, and the
1st, 2nd, 3rd input signal switching of 3 inputs and 1 output
The first, second and third screens based on the output signal from the
A display device characterized by being displayed at times . 2. A three-input one-output input signal switch inserted into each of red, green, and blue signal lines ;
Two green and blue signal lines
An on / off switch, a switching signal generator for controlling each of the input signal switches in synchronization with a horizontal synchronizing signal or a vertical synchronizing signal, and the one three-input one-output input
The output of the signal switch and the two on / off switches
Switches are connected to the red, green, and blue signal input terminals, respectively.
Output from the switching signal generator.
Generated signal is switched between normal mode and confirmation mode
A mode changeover switch, wherein the one three input
The three inputs of the one-output input signal switcher are
One connected to the red, green and blue input signal lines
Is connected to the red signal input terminal of the display element,
The output of the two on / off switches is
Connect to the blue signal input terminal and green signal input terminal respectively.
And the changeover switch is switched to the confirmation mode.
When the two on / off switches are turned off, the horizontal synchronization period or the vertical synchronization period
Generation of the switching signal by dividing into three in two and three periods
In the first period, the switching signal from the
The red signal from the input signal switch with 3 inputs and 1 output is before
Input to the red signal input terminal of the display element,
During the period, the three-input one-output input signal
A green signal is input to the green signal input terminal of the display element.
In the third period, the input signal of the three inputs and one output is turned off.
The blue signal from the switch is the blue signal input of the display element.
Terminal, and the first, second, third
Output from three 3-input 1-output input signal switches
The first, second, and third screens are displayed simultaneously by signals.
Display apparatus characterized by the the like. 3. A three-input / one-output three-input / one-output signal switch inserted into each of red, green, and blue signal lines, and a horizontal synchronizing signal or a vertical synchronizing signal. A switching signal generator for controlling each of the input signal switches in synchronization with each other, and the three 3-input / 1-output input signals
The first, second and third outputs of the switch are variable
Connected to the red, green, and blue signal input terminals
Output from the switching signal generator.
Generated signal is switched between normal mode and confirmation mode
And an input signal switch of the first three-input / one-output input signal switch.
The input of the second three-input one-output input signal switch connected to the blue input signal line is red, green,
The inputs of the third three-input one-output input signal switch connected to the blue input signal line are also red,
Green, is connected to the input signal line of the blue, the switching Sui
When the switch is switched to the confirmation mode,
Alternatively, the vertical synchronization period is set to three in the first, second, and third periods.
Divided into switching signals from the switching signal generator
Therefore, during the first period, the input of the first three inputs and one output is performed.
The red signal from the force signal switch is red for the display element,
The green and blue signal input terminals are all input to the second period
From the second three-input one-output input signal switch.
Green signal of the display element red, green, blue signal input terminal
, And the third three inputs during the third period.
Blue signal from one-output input signal switcher is displayed
The red, green, and blue signal input terminals of the device are all input to the
The first, second, and third three-input and one-output are provided to a display element.
Output signal from the input signal switch of
2 and 3 are displayed simultaneously,
There is no brightness difference between the first, second and third screens displayed
The display device , wherein the gain of the variable gain type amplifier is adjusted so as to be as follows.