KR100245602B1 - White balance adjusting circuit using grid electrode - Google Patents

Abstract

The present invention relates to a white balance adjustment circuit using a grid electrode. In the conventional pattern generation for white balance adjustment, vertical deflection is not performed by applying a white signal to the input of a cathode and blocking the operation of the vertical deflection circuit. By repeatedly hitting the fluorescent film by the horizontal scanning player in the center line of the screen, the luminous efficiency of the fluorescent material is lowered and the lifetime is shortened.

In the present invention, in view of the above problems, the white bar for adjusting the white balance can be used simply by making a pattern generating circuit inside the television, so that no pattern signal input from the outside of the television is required, and there is no exaggeration of color. The adjustment signal, which is very important for adjusting the white balance, can be adjusted with a short time and effort, and the fluorescent material can be reduced by more than 1/1050 in terms of collision of electron beams, thereby extending the life of the fluorescent film. Therefore, it is possible to improve the reliability of the product.

Description

White Balance Control Circuit Using Grid Electrode

1 is a block diagram showing a conventional white balance adjustment circuit.

2 is a block diagram showing a white balance adjustment circuit using a grid electrode according to an embodiment of the present invention.

3 is a detailed circuit diagram showing the pattern generator of FIG.

4 is a detailed circuit diagram illustrating a white bar width adjusting unit of FIG. 2.

* Explanation of symbols for main parts of the drawings

1: pattern generator 2: counter

3: division circuit portion 4: comparison circuit portion

5: white bar width adjusting unit 6: inverting amplifying unit

7, 8: switching circuit section 9: screen voltage adjustment section

1A: Synchronization signal synthesizing unit 1B: Amplifying unit

5A: Monostable Multivibrator 5B: External Selection Key

CRT: Cathode Ray Tube

The present invention relates to a white balance adjustment apparatus using a grid electrode that can adjust the white balance without stopping the vertical deflection operation in generating the white bars necessary for the white balance.

As shown in FIG. 1, the conventional white balance adjustment circuit includes a pattern generator 11 which receives a synchronization signal and generates a white balance adjustment pattern signal and applies it to a cathode of a cathode ray tube (CRT); A vertical deflection output circuit section (11) for deflecting the vertical synchronization signal of the synchronization signal; A switching circuit section 13 for blocking a vertical deflection output applied to the vertical deflection coil 15 from the vertical deflection output circuit section 12; And a screen voltage adjusting unit 14 for adjusting the white balance of the cathode ray tube.

The conventional white balance adjustment circuit configured as described above generates a white pattern signal as an input of the pattern generator 11 and applies it to the cathode of the cathode ray tube CRT, and cuts the output of the vertical deflection output circuit unit 12 so as to vertically deflect it. Since no force is applied to the coil 15, a transverse line is generated.

In addition, the disease circuit unit 13 is a switching circuit for blocking the vertical deflection output before the white balance adjustment, and the screen voltage adjustment unit 14 is an adjustment terminal for white balance adjustment.

However, such a conventional white balance adjustment circuit does not match the color signal and the color perceived by the naked eye to the color signal and cathode ray tube characteristics in the cathode ray tube display.

Therefore, in order to adjust this error, a white (red, green, blue mixed) pattern was input from the outside of the system and used to adjust the white balance. This has to be prepared, which delays the white balance adjustment time and has a complex disadvantage.

In addition, when receiving and adjusting the test pattern signal for white adjustment, it is better to darken the surroundings for accurate color discrimination. In the existing white balance adjustment circuit, the vertical deflection operation is performed to generate white bars of horizontal lines on the screen. By stopping it, only one line of the cathode ray tube is repeated as many times as the scanning line frequency, thereby affecting the luminous efficiency and emission color of the fluorescent material directly affecting the lifetime of the TV receiver, thereby shortening the lifetime of the cathode ray tube.

In addition, the cathode ray tube (CRT) used in high definition television (HDTV) receivers has different characteristics for each manufacturer and individual color, and there is no exaggeration of color and close to the real color like conventional television sets. It is important.

In view of the above problems, the present invention expresses all colors by a combination of three primary colors of light (red, green, and blue in a television receiver). It is not necessary to input the pattern from the outside of the television receiver to adjust the red, green, and blue characteristics, and to protect the fluorescent material of the cathode ray tube which directly affects the life of the television receiver. To extend the life of the tube.

That is, a signal for adjusting the white balance inside the receiver is made by using a vertical horizontal synchronizing signal and a DC voltage corresponding to the back level, and the horizontal synchronizing signal is counted, and the vertical synchronizing signal and the counter output exceed a certain integer value. The counter is reset when this occurs.

In addition, by selecting the center on the screen, the selected scanning line is displayed on the screen by displaying a white bar having a width of about 10 scanning lines by the scanning line width adjusting circuit, thereby displaying a white horizontal band (white bar) on the screen. While looking at the screen, the screen voltage of red, green, and blue is adjusted to adjust the color according to the visual characteristics.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, the white balance adjustment circuit using the grid electrode includes a pattern generator 1 which receives horizontal and vertical synchronization signals HD and VD and generates a pattern for white balance adjustment; A counter 2 that counts the horizontal synchronization signal HD and is cleared upon input of the vertical synchronization signal VD; A division circuit section (3) for dividing an output value of the counter (2) by a division number (K) to select a screen scanning line; A comparison circuit section (4) for comparing the output of said division circuit section (3) with a reference voltage; A white bar width adjusting section 5 for adjusting the width of the white bar which is the center line of the scanning line selected by the output of the comparing circuit section 4; An inverting amplifier 6 for inverting and amplifying the output of the screen scanning line adjusted by the white bar width adjusting unit 5; Switching circuits (7, 8) for selectively controlling the white balance pattern, the video selection terminal, and the first grid electrode inverted and amplified by the inversion amplifier (6); It consists of the screen voltage adjustment part 9 which adjusts the white balance of a cathode ray tube.

As shown in FIG. 3, the pattern generator 1 includes a synchronization signal synthesizing unit 1A for synthesizing the vertical synchronization signal VD and the horizontal synchronization signal HD; Amplifying section 1B for amplifying and outputting the signal synthesized in the same signal synthesizing section 1A.

The white bar width adjusting unit 5 includes a monostable multivibrator 5A that receives the comparison output of the comparison circuit unit 4 and amplifies and outputs it; It consists of an external selection key 5B for selecting the control data CD of the monostable multivibrator 5A.

Referring to the operation and effects of the present invention configured as described above in detail.

As an input signal, horizontal and vertical synchronization signals are input to the pattern generator 1 to generate a pattern for white balance adjustment, and are input to the cathode of the cathode ray tube to display a white pattern on the screen. At this time, if the entire screen is displayed as a white screen, it is difficult to adjust due to an error (color purity, etc.) according to the position of the screen.

Therefore, in order to prevent the above problem, the balance is adjusted in a state in which a single line or a horizontal one line in the center of the screen is displayed on the screen, and the horizontal synchronizing signal is counted by the counter 2 in order to make the horizontal single line white bar.

At this time, when the vertical synchronization signal is input, the counter 2 is cleared. If the counter output exceeds a certain number, the counter 2 is reset, and the counter 2 is a horizontal scan player 525, 625, or 1050. , 1125, 1250, etc.), the town divider divides the divider circuit 3 by the divider K (constant according to the injection player) and outputs 1 (high logic), which is compared with the comparison circuit unit ( Input by non-inverting (+) input terminal of 4).

As another terminal inverting (-) input of the comparison circuit section 4, a DC voltage of the reference voltage Vref is input and compared with the output of the division circuit section 3.

At this time, the output to the division circuit unit 3 is 1 (logic HIGH: 262 scan lines and 787 scan lines, which are 1/2 of one field 525, if the horizontal scan player has a 1050 interlaced scan < one screen has two fields >). When the output of the comparator circuit 4 becomes 1 (high logic) and one scan line in the center of this scan line is too narrow to be checked visually while adjusting the white balance, the width of the white bar can be adjusted so that the white bar can be adjusted. The white bar width adjusting section 5 is required to be adjusted. Since the control grid of the first grid is about 0 to 100, it is too high to apply the output of the white bar width adjusting section 5 to the grid as it is. Then, the electrode first grid is applied through the switching circuit unit 7.

In addition, the switching circuit 7 controls the first grid electrode during the white balance adjustment and does not affect the first grid electrode at other times than the adjustment, so it is a selection circuit for selecting the video signal and the white at the input side of the cathode. The switching circuit section 7 selects a manual terminal switch or a remote control switch so as to be interlocked with a circuit for selecting a balance signal, and the switching circuit section 8 is automatically selected according to the selection of the switching circuit section 7. To be able to move.

As described in detail above, in order to adjust the white balance, the present invention allows a white bar (white horizontal line) to be used simply by creating a pattern generating circuit inside the television, and does not require a pattern signal input from the outside of the television. The adjustment signal to adjust the white balance, which is very important for realistic expression without exaggeration of color, can be adjusted with short time and effort, and the fluorescent material can be reduced by 1/1050 or more in terms of collision of the electron beam. Therefore, it is possible to extend the life of the fluorescent film, thereby significantly increasing the reliability of the product.

Claims (3)

A pattern generator 1 which receives horizontal and vertical synchronization signals HD and VD and generates a pattern for white balance adjustment; A counter 2 that counts the horizontal synchronizing signal HD and is cleared upon input of the vertical synchronizing signal VD; A division circuit section (3) for dividing an output value of the counter (2) by a division number (k) to select a screen scanning line; A comparison circuit section (4) for comparing the output of said division circuit section (3) with a reference voltage; A white bar width adjusting section 5 for adjusting the width of the white bar which is the center line of the scanning line selected by the output of the comparing circuit section 4; An inverting amplifier 6 for inverting and amplifying the output of the screen scanning line adjusted by the white bar width adjusting unit 5; Switching circuits (7, 8) for selectively controlling the white balance pattern, the video selection terminal, and the first grid electrode inverted and amplified by the inversion amplifier (6); White balance adjustment circuit using a grid electrode, characterized in that the screen voltage adjusting section for adjusting the white balance of the cathode ray tube. 2. The pattern generating unit (1) according to claim 1, further comprising: a synchronization signal synthesizing unit (1A) for synthesizing a vertical synchronizing signal (VD) and a horizontal synchronizing signal (HD); And an amplifying unit (1B) for amplifying and outputting the signal synthesized in the synchronizing signal synthesizing unit (1A). 2. The apparatus as claimed in claim 1, wherein the white bar width adjusting unit (5) comprises: a monostable multivibrator (5A) for receiving an amplifying output of the comparing circuit portion (4); And an external selection key (5B) for selecting control data (CD) of said monostable multivibrator (5A).