KR100481513B1 - Circuit for stabling high tension of CRT and method thereof and image display apparatus - Google Patents

Abstract

Disclosed are a high pressure stabilization circuit and method of a CRT. The feedback unit receives the cutoff voltage from the CRT. The correction unit calculates the variation amount of the cutoff voltage based on the cutoff voltage received from the feedback unit. The change amount of the cutoff voltage is compared with the high-voltage correction data according to the change amount of the cutoff voltage stored in the storage. The correction unit performs the high pressure correction according to the comparison result. As a result, it is possible to overcome the inaccuracy of the correction due to the delay in the high-voltage correction, and to eliminate the ABL circuit and the high-voltage correction capacitor, thereby reducing the manufacturing cost. In addition, since the ABL circuit is not used, there is an advantage that partial correction according to the AC variation amount is possible.

Description

Circuit for stabling high tension of CRT and method about and image display apparatus

The present invention relates to a high-pressure stabilization circuit and method of CALTI, and more particularly to a high-pressure stabilization circuit and method of CALTI having an Extra High Tension (EHT) correction function.

Generally, a Cathod ray tube (CRT) applies negative high pressure to the anode, that is, several tens of kV, to accelerate electrons so that the electron beam emitted from the cathode collides with the phosphor coated screen at high speed. Thus, electron beam current, that is, cathode current, flows from the anode to the cathode. This direct current electron beam is modulated by an RGB image signal while scanning on the screen. The modulated electron beam causes a change in intensity of the electron beam that impinges on the phosphor on the screen, thereby causing a color screen to appear on the screen.

Since the image signal is modulated and displayed on the high-voltage direct current in the above-described CRT, the high-voltage fluctuation directly affects the brightness and contrast of the screen, so stabilization of the high voltage is very important for stabilization of image quality. That is, since the color CRT has a large electron beam current of the CRT and reproduces the direct current, the average beam current changes greatly every time the screen is changed.

The high voltage of the CRT is obtained by rectifying the pulses of a flyback transformer (FBT). However, high voltage power obtained by rectifying FBT causes voltage fluctuations and the voltage changes every time the screen is changed. As a result, raster amplitude changes, convergence deviations, focus deviations, etc. occur. In addition, since the power source obtained by using the flyback pulse varies up to the power source voltage of the component used, the operation of the entire CRT becomes unstable. Therefore, a countermeasure for stabilizing the high pressure is required in the high pressure generating circuit.

Conventionally, high pressure correction was performed by using a feedback voltage input from an FBT to an auto brightness limit circuit (ABL) for high pressure stabilization. 1 is a block diagram of a conventional high pressure stabilization circuit.

Referring to FIG. 1, the conventional high voltage stabilization circuit 150 includes a feedback unit 152, a comparison unit 154, a voltage output unit 156, and a driver 158.

The feedback unit 152 receives the voltage of the FBT 120 according to the high voltage change of the CRT 110 through the ABL 130. The comparator 154 extracts a variation amount of the voltage received from the feedback unit 152. The voltage output unit 156 outputs a voltage at which the high voltage is corrected based on the voltage variation received from the comparator 154. The driver 158 outputs the corrected high voltage received from the voltage output unit 156 to the vertical driver 170 and the horizontal driver 180. In this case, the corrected high pressure is an E / W signal input to the horizontal driver 180.

However, a CRT using a conventional high pressure stabilization circuit may cause a distorted image at the boundary between bright and dark portions of the screen due to incomplete high pressure correction. 2A and 2B are diagrams showing examples of a phase distortion phenomenon occurring in a conventional CRT. Referring to FIGS. 2A and 2B, it can be seen that regions 220a and 220b in which an image is distorted occur at the boundary points between the bright portions 200a and 200b and the dark portions 210a and 210b. In this case, since the position and size of the white are different depending on the type of the image display apparatus, the region in which the image display apparatus is located, the size of the white bar, and the like, the high pressure correction amount may be changed to complete the correction. However, since the conventional high voltage correction circuit does not consider these factors, there is a problem that the correction is uniformly performed.

Meanwhile, in the related art, the YUV signal is converted into an RGB signal by the matrix circuit 142 and input to the image amplifier 160. The image amplifier 160 amplifies the input RGB signal and outputs it to the CRT. The RGB signal amplified by the image amplifier 160 is fed back to the video matrix chip 140 and used to adjust the white balance. In addition, the high pressure correction capacitor 190 reduces the high pressure fluctuations input from the FBT to the CRT.

However, in the related art, since the high voltage variation is fed back through the ABL circuit, there is a problem in that a delay occurs in the signal input due to the delay by the ABL circuit. This signal delay is a major cause of the inability to perform accurate phase correction. In addition, there is a problem that partial correction is difficult because the low-pass filter provided in the ABL circuit feeds back the state in which the AC component is almost extinguished.

On the other hand, if the high pressure correction capacitor is employed to solve this problem in the prior art, it is possible to reduce the high pressure fluctuation, but there is a problem that a considerable cost increase is inevitable by the addition of the high pressure correction capacitor. Furthermore, since the user is not provided with a means for directly correcting the distortion of the image due to inaccurate high pressure correction, active correction by the user is impossible.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a CRT high voltage stabilization circuit and method capable of overcoming inaccuracies in phase size correction and partial correction due to delay while reducing production costs.

Another object of the present invention is to provide an image display device having means for allowing a user to correct inaccuracies in image size correction and partial correction due to delay.

In order to achieve the above technical problem, the high-voltage stabilization circuit of the CRT according to the present invention includes a feedback unit for receiving a feedback of the cutoff voltage from the CRT; A storage unit for storing the high pressure correction data according to the variation amount of the cutoff voltage; And a correction unit configured to perform the high pressure correction by comparing the change amount of the cutoff voltage with the high pressure correction data.

The compensator may include: a comparator configured to output a high voltage compensation amount by comparing the change amount of the cutoff voltage with the high pressure compensation data; A partial correction unit for outputting a first correction amount of the slope of the cutoff voltage by comparing the AC variation of the cutoff voltage with the high voltage correction data; And a voltage output unit configured to receive the high voltage correction amount and / or the first correction amount and output a corrected voltage.

On the other hand, the high-pressure stabilization circuit according to the present invention further includes a correction amount providing unit for providing a second correction amount of the slope of the cutoff voltage received from the user to the partial correction unit, the partial correction unit is controlled from the outside The partial correction is performed by sequentially or simultaneously applying the first correction amount and the second correction amount in accordance with a signal.

The high-voltage correction data includes phase-size correction data in which an adjustment amount of the phase size according to the DC change amount of the cutoff voltage is defined and / or partial correction data in which a correction amount of the slope of the cutoff voltage is defined according to an AC variation amount of the cutoff voltage. It is desirable to.

According to another aspect of the present invention, an image display device includes a feedback unit receiving a cutoff voltage from a CRT, a storage unit storing high voltage correction data according to the change amount of the cutoff voltage, and a change amount of the cutoff voltage in the high pressure correction data. A high voltage stabilization circuit including a correction unit configured to perform high pressure correction in comparison with a correction amount, and a correction amount providing unit providing a first correction amount of a slope of the cutoff voltage received from a user to the correction unit; A user interface unit receiving the first correction amount from a user and providing the first correction amount to the high voltage stabilization circuit; And an OSD generating unit for generating the first correction amount input screen in an OSD form according to a user's selection, wherein the correction unit changes the first correction amount and the change amount of the cutoff voltage based on a control signal input from the outside. The second distortion amount according to the comparison result of the high pressure correction data is sequentially or simultaneously applied to correct the phase distortion.

The compensator may include: a comparator configured to output a high voltage compensation amount by comparing the change amount of the cutoff voltage with the high pressure compensation data; A partial correction unit for outputting a second correction amount of the slope of the cutoff voltage by comparing the AC variation of the cutoff voltage with the high voltage correction data; And a voltage output unit configured to receive the high voltage correction amount, the first correction amount and / or the second correction amount, and output a corrected voltage.

The high-voltage correction data includes phase-size correction data in which an adjustment amount of the phase size according to the DC change amount of the cutoff voltage is defined and / or partial correction data in which a correction amount of the slope of the cutoff voltage is defined according to an AC variation amount of the cutoff voltage. It is desirable to.

In accordance with another aspect of the present invention, a high pressure stabilization method includes: (a) receiving a feedback of a cutoff voltage from a CRT; (b) calculating a variation amount of the cutoff voltage; And (c) comparing the amount of change in the cutoff voltage with pre-stored high pressure correction data to perform high pressure correction.

Furthermore, (d) receiving a second correction amount of the slope of the cutoff voltage from a user; And (e) changing a slope of the cutoff voltage based on the second correction amount.

At this time, the step (c), (c1) comparing the amount of change in the cut-off voltage with the high-pressure correction data to output a high-voltage correction amount; And (c2) receiving the high voltage correction amount and outputting a corrected voltage.

On the other hand, step (c1), the step of separating the change amount of the cut-off voltage into a DC change amount and an AC change amount; Outputting a high pressure correction amount for a phase size by comparing the DC variation with the high pressure correction data; And outputting a first correction amount for partial correction by comparing the AC variation amount with the high pressure correction data.

The high-voltage correction data includes phase-size correction data in which an adjustment amount of the phase size according to the DC change amount of the cutoff voltage is defined and / or partial correction data in which a correction amount of the slope of the cutoff voltage is defined according to an AC variation amount of the cutoff voltage. It is desirable to.

By using the cutoff voltage of the CRT for high pressure compensation, it is possible to overcome the inaccuracy of correction due to the delay during the high pressure compensation and to eliminate the ABL circuit and the high voltage compensation capacitor, thereby reducing the manufacturing cost. In addition, since the user can directly perform partial correction, the high pressure fluctuation suitable for the user can be made in consideration of the degree of image distortion of each region and the visual characteristics of the user.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the high-voltage stabilization circuit and method of the CRT according to the present invention.

3 is a block diagram of an embodiment of a high pressure stabilization circuit of a CRT according to the present invention, and FIG. 4 is a flowchart of an embodiment of a high pressure stabilization method of a CRT according to the present invention.

3 and 4, the CRT high voltage stabilization circuit 310 according to the present invention includes a feedback unit 312, a storage unit 314, and a correction unit 316.

The feedback unit 312 receives the cutoff voltage from the image amplifier 340 (S400). The cutoff voltage may be fed back from the CRT, but it is preferable to receive the input from the image amplifier 340 in view of accuracy and delay prevention of the fed back voltage.

The storage unit 314 stores the high pressure correction data according to the variation amount of the cutoff voltage. The high pressure correction data stored in the storage unit 314 includes phase size correction data in which the amount of adjustment of the phase size according to the DC change amount of the cutoff voltage is specified, and partial correction data in which the correction amount of the slope of the cutoff voltage is determined according to the AC variation of the cutoff voltage. It includes.

The correction unit 316 performs the high pressure correction by comparing the variation amount of the cutoff voltage with the high pressure correction data (S410 to S430). The variation amount of the cutoff voltage input to the correction unit 316 has both a DC and an AC component. The corrector 316 includes a comparator 318, a partial compensator 320, and a voltage output unit 322.

The comparator 318 calculates a change amount of the cutoff voltage from the cutoff voltage received from the feedback unit 312 (S410) and outputs a high pressure compensation amount by comparing with the high pressure correction data stored in the storage unit 314 (S420). . At this time, the comparison unit 318 preferably outputs a high-pressure correction amount for each of the direct current and the alternating current. The partial correction unit 320 receives the high pressure correction amount for the alternating current from the comparator 318 and performs partial correction. The partial correction is performed by adjusting the slope of the feedback voltage. The voltage output unit 322 receives the high-voltage correction amount for direct current from the comparator 318 and outputs a voltage whose phase size is corrected (S430).

The voltage output from the voltage output unit 322 is applied to the driver 324, and the driver 324 receives the vertical scan signal VD and the horizontal scan signal HD from the vertical driver 370 and the horizontal driver 380, respectively. Will output The voltages E / W whose vertical and horizontal phase sizes are corrected are input from the driver 324 to the horizontal driver 370. On the other hand, the flyback transformer 380 receives the pulse of the return section of the horizontal scan signal (HD) input to the horizontal driver 370 is converted into a high voltage and supplied to the CRT (350).

The video chip 390 includes a high voltage stabilization circuit 310, a driver 324, a matrix circuit 326, and an RGB output unit 328 according to the present invention.

The matrix circuit 326 receives the YUV signal, converts it into an RGB signal, and outputs the RGB signal to the RGB output unit 328. The RGB output unit 328 applies the RGB signal to the image amplifier 340, and the image amplifier 340 amplifies the received RGB signal and supplies it to the CRT 350. The cut-off voltage drawn from the image amplifier 340 is applied to the RGB output unit 328 and the feedback unit 312. The cut-off voltage applied to the RGB output unit 328 is used to adjust the white balance.

5 is a block diagram showing the configuration of another embodiment of the high-voltage stabilization circuit according to the present invention.

Referring to FIG. 5, the CRT high voltage stabilization circuit 310 according to the present invention includes a feedback unit 312, a storage unit 314, a correction unit 316, and a correction amount providing unit 330.

Since the functions of the feedback unit 312 and the storage unit 314 are the same as those described with reference to FIG. 3, a detailed description thereof will be omitted.

The correction amount providing unit 330 receives a correction control signal for image distortion from the user and outputs the correction control signal to the partial correction unit 320. In the present exemplary embodiment, the correction amount providing unit 330 is illustrated as being provided in the high pressure stabilization circuit 310. Alternatively, the correction amount providing unit 330 may be provided separately from the high pressure stabilization circuit 310.

The correction unit 316 performs the high pressure correction by comparing the variation of the cutoff voltage with the high pressure correction data. The variation amount of the cutoff voltage input to the correction unit 316 has both a DC and an AC component. The corrector 316 includes a comparator 318, a partial compensator 320, and a voltage output unit 322.

The comparator 318 calculates a change amount of the cutoff voltage from the cutoff voltage received from the feedback unit 312, and outputs a high pressure compensation amount by comparing it with the high pressure correction data stored in the storage unit 314. At this time, the comparison unit 318 preferably outputs a high-pressure correction amount for each of the direct current and the alternating current.

The partial correction unit 320 receives the high pressure correction amount for the alternating current from the comparator 318 and performs partial correction. The partial correction is performed by adjusting the slope of the feedback voltage. Meanwhile, the partial correction unit 320 readjusts the slope of the feedback voltage based on the correction amount received from the correction amount providing unit 330. The readjustment of the slope of the feedback voltage may be performed simultaneously or sequentially with the partial correction performed based on the high voltage correction amount. On the contrary, when the correction amount is input from the correction amount providing unit 330, the partial correction unit 320 may not use the high pressure correction amount input from the comparing unit 318 for partial correction.

The correction amount providing unit 330 provides the correction amount received from the user to the partial correction unit 322. In this case, the correction amount providing unit 330 may receive a correction signal indicating the correction amount, convert the signal into a signal recognizable by the partial correction unit 322, that is, provide the correction amount. The correction signal input to the correction amount providing unit 330 is provided in a video display device (for example, a television) in which a user is equipped with a remote controller (not shown) or a high voltage stabilization circuit 310 according to the present invention. The correction amount for the position and size of the white input through the input means is displayed as an electrical signal.

6 is a block diagram showing a configuration of an image display device 600 equipped with a high voltage stabilization circuit 310 according to the present invention, and FIG. 7 is a flowchart illustrating another embodiment of the method for stabilizing a high pressure according to the present invention. One flow chart.

6 and 7, the image display device 600 includes a high voltage stabilization circuit 310, a user interface unit 610, an OSD generator 620, and a controller 630.

Since the configuration and operation of the high voltage stabilization circuit 310 are the same as those described with reference to FIG. 5, a detailed description thereof will be omitted. Therefore, FIG. 6 illustrates only the components necessary for performing the high pressure correction based on the correction amount input by the user among the components of the high pressure stabilization circuit 310, and the remaining components are omitted.

As shown in FIG. 2, when the areas 220a and 220b are smeared near the boundaries of the black letters 210a and 210b displayed on the white backgrounds 200a and 200b, the user may use a remote controller (not shown). Alternatively, a correction menu is selected through input means provided in the image display apparatus (for example, television) 600 equipped with the high voltage stabilization circuit 310 according to the present invention (S700). When the user selects the correction menu, the controller 630 drives the OSD generator 620 to output the correction amount input screen to the OSD (S710).

8 shows an example of a correction amount input screen. The correction amount input screen includes adjustment bars 820 and 830 for tilting the horizontal slide bar 800, the correction amount adjustment bar 810 located in the bar slide bar 800, and the bleeding areas 220a and 220b. It consists of). The user inputs the correction amount by moving the correction amount adjusting bar 810 on the correction amount input screen through an input means such as a remote controller (S720).

The user interface 610 receives a correction signal indicating a correction amount for the position and size of the white from the user and provides the correction signal to the correction amount providing unit 330. At this time, the user interface unit 610 converts the correction signal input by the user into a signal that the partial correction unit 322 can recognize, that is, the correction amount.

The controller 630 checks whether the partial correction is set to be performed only by the correction amount input by the user (S730), and controls the partial correction operation of the partial correction unit 322 according to the setting state. When the partial correction is set to be performed only by the correction amount input by the user, the partial correction unit 322 performs partial correction without using the high pressure correction amount input from the comparator 318 (S740). Alternatively, the comparator 318 may not input the high pressure correction amount to the partial compensator 322.

On the other hand, when it is set to perform partial correction by the correction amount input by the user and the high-pressure correction amount input from the comparing unit 318, the partial correction unit 322 is partially by the high-pressure correction amount input from the comparing unit 318. After the correction is performed, partial correction is performed using the correction amount input by the user. Alternatively, the partial correction unit 322 may perform partial correction by simultaneously applying the high pressure correction amount input from the comparator 318 and the correction amount input by the user (S750).

On the other hand, when the user selects the correction menu in the state that the partial correction is performed by the high-pressure correction amount input from the comparator 318, the partial correction unit 322 is configured to perform partial correction according to the input correction amount can do.

When partial correction is performed by the correction amount input by the user, the corrected screen is output to the image display apparatus 300 (S760).

According to the high-voltage stabilization circuit and method of the CRT according to the present invention, by using the cut-off voltage of the CRT in the high-pressure correction, it is possible to overcome the inaccuracy of the correction due to the delay in the high-voltage correction and to eliminate the ABL circuit and the high-voltage correction capacitor The manufacturing cost is reduced. In addition, since the ABL circuit is not used, there is an advantage that partial correction according to the AC variation amount is possible. Furthermore, since the user can directly adjust the degree of partial correction, the high pressure variation suitable for the user can be made in consideration of the degree of image distortion of each region and the visual characteristics of the user.

Although the present invention has been described in detail through the representative embodiments, those skilled in the art to which the present invention pertains can make various modifications without departing from the scope of the present invention with respect to the embodiments described above. Will understand. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the claims below and equivalents thereof.

1 is a block diagram of a conventional high pressure stabilization circuit,

2A and 2B are diagrams showing examples of a phase distortion phenomenon occurring in a conventional CRT,

3 is a block diagram of one embodiment of a high pressure stabilization circuit of a CRT in accordance with the present invention;

4 is a flowchart of an embodiment of a high pressure stabilization method of a CRT according to the present invention;

5 is a block diagram showing the configuration of another embodiment of the high-voltage stabilization circuit according to the present invention;

6 is a block diagram showing the configuration of a video display device equipped with a high voltage stabilization circuit according to the present invention;

7 is a flowchart illustrating a process of another embodiment of the high pressure stabilization method according to the present invention;

 8 is a diagram illustrating an example of a correction amount input screen output to an image display device.

Claims (12)

A feedback unit receiving a feedback of the cutoff voltage from the CRT; A storage unit for storing the high pressure correction data according to the variation amount of the cutoff voltage; And And a correction unit configured to perform the high pressure correction by comparing the change amount of the cutoff voltage with the high pressure correction data. The method of claim 1, The compensator may include: a comparator configured to output a high voltage compensation amount by comparing the change amount of the cutoff voltage with the high pressure compensation data; A partial correction unit for outputting a first correction amount of the slope of the cutoff voltage by comparing the AC variation of the cutoff voltage with the high voltage correction data; And And a voltage output unit configured to receive the high voltage correction amount and / or the first correction amount and output a corrected voltage. The method of claim 2, And a correction amount providing unit which provides the partial correction unit with a second correction amount of the slope of the cutoff voltage received from a user. And the partial correction unit performs partial correction by sequentially or simultaneously applying the first correction amount and the second correction amount according to a control signal input from the outside. The method of claim 2 or 3, The high-voltage correction data includes phase-size correction data in which an adjustment amount of the phase size according to the DC change amount of the cutoff voltage is defined and / or partial correction data in which a correction amount of the slope of the cutoff voltage is defined according to an AC variation amount of the cutoff voltage. High pressure stabilization circuit, characterized in that. A feedback unit for receiving a feedback of the cutoff voltage from the CRT, a storage unit for storing the high pressure correction data according to the change amount of the cutoff voltage, a correction unit for performing the high pressure correction by comparing the change amount of the cutoff voltage with the high pressure correction data, and a user A high voltage stabilization circuit having a correction amount providing unit for providing a first correction amount of an input slope of the cutoff voltage to the correction unit; A user interface unit receiving the first correction amount from a user and providing the first correction amount to the high voltage stabilization circuit; And And an OSD generator for generating the first correction amount input screen in an OSD form according to a user's selection. The correction unit corrects the phase distortion by sequentially or simultaneously applying the first correction amount, the second correction amount according to a comparison result of the high voltage correction data, and the variation amount of the cutoff voltage based on a control signal input from the outside. Image display apparatus characterized in that. The method of claim 5, The compensator may include: a comparator configured to output a high voltage compensation amount by comparing the change amount of the cutoff voltage with the high pressure compensation data; A partial correction unit for outputting a second correction amount of the slope of the cutoff voltage by comparing the AC variation of the cutoff voltage with the high voltage correction data; And And a voltage output unit configured to receive the high voltage correction amount, the first correction amount and / or the second correction amount, and output a corrected voltage. The method according to claim 5 or 6, The high-voltage correction data includes phase-size correction data in which an adjustment amount of the phase size according to the DC change amount of the cutoff voltage is defined and / or partial correction data in which a correction amount of the slope of the cutoff voltage is defined according to an AC variation amount of the cutoff voltage. Image display device, characterized in that. (a) receiving a feedback of the cutoff voltage from the CRT; (b) calculating a variation amount of the cutoff voltage; And (c) performing a high pressure correction by comparing the variation of the cutoff voltage with previously stored high pressure correction data. The method of claim 8, (d) receiving a second correction amount of the slope of the cutoff voltage from a user; And (e) changing a slope of the cutoff voltage based on the second correction amount. The method according to claim 8 or 9, Step (c) may include: (c1) outputting a high pressure correction amount by comparing the change amount of the cutoff voltage with the high pressure correction data; And (c2) receiving the high pressure correction amount and outputting a corrected voltage. The method of claim 10, The step (c1) may include: dividing the change amount of the cutoff voltage into a DC change amount and an AC change amount; Outputting a high pressure correction amount for a phase size by comparing the DC variation with the high pressure correction data; And And comparing the alternating current variation with the high pressure correction data to output a first correction amount for partial correction. The method according to claim 8 or 9, The high-voltage correction data includes phase-size correction data in which an adjustment amount of the phase size according to the DC change amount of the cutoff voltage is defined and / or partial correction data in which a correction amount of the slope of the cutoff voltage is defined according to an AC variation amount of the cutoff voltage. High pressure stabilization method characterized in that.