JP2000115801A - White balance adjustment device for pdp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically correct a change with time passage in white balance by manually eliminating the white balance adjustment of a PDP at factory shipping. SOLUTION: R, G, B amplifier sections 1R, 1G, 1B amplify red, green, blue video signals to drive a PDP 3 via R, G, B drive sections 2R, 2G, 2B, a video image is displayed on a video display area 4 to emit lights of red, green and blue from a light-emitting section 5 at prescribed lightness. Then, a sensor 6 measures the luminance of the light for colors, an amplifier 7 amplifies the luminance which is inputted to a comparison section 9, where the luminance is compared with red, green, blue reference values for while balance read from a memory section 8 and outputs a signal, in response to a difference and an amplification degree control section 10 controls the amplification degree of the R, G, B, amplifier sections for colors to correct the white balance of the PDP.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adjusting the white balance of a PDP (Plasma Display Panel).
Detects the luminance of three colors, green and blue, and detects PD when a change occurs.
The present invention relates to a device that varies a driving amount of P to maintain a white balance.

[0002]

2. Description of the Related Art PDPs are individually red / red depending on the thickness of a phosphor in a light emitting portion, the impedance of an electrode or an applied voltage.
The luminous efficiency of each color of green and blue varies. For this reason, at the time of shipment from a factory, the signal amplitude of each color of red, green, and blue is manually adjusted in a state of being incorporated in a display device, thereby achieving white balance. However, PDP has a tendency that the luminous efficiencies of green and blue with respect to red tend to decrease with time, and there is a problem that after long-term use, the white balance is lost and the color becomes yellowish.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the manual adjustment of the signal amplitude of each of red, green, and blue at the time of shipment from a factory, and to correct the deviation of the white balance due to aging. And

[0004]

In order to achieve the above object, in the white balance adjusting device of the PDP of the present invention, the video signals of each color of red, green and blue are amplified by the amplifying section for each of red, green and blue. Amplifying and driving a PDP via a driving unit for each of red, green and blue, wherein light emission for individually emitting each of red, green and blue at a required brightness outside the image display area of the PDP. And a sensor disposed in front of the light-emitting unit for measuring the luminance value of each color of red, green and blue, and a reference luminance ratio of each color of red, green and blue for white balance of the PDP. A comparing unit that compares the ratio of the luminance value of each color from the sensor with the reference luminance ratio read from the memory unit and outputs a signal corresponding to the difference; and a unit for each of the red, green, and blue colors. An amplification control unit that controls the amplification of the amplification unit; The amplification control of the amplification unit for each of red, green and blue is controlled by the amplification control unit for each color based on the signal from the comparison unit. Is corrected.

[0005] The light emitting section emits red, green and blue colors at all times, or emits red, green and blue colors only when the white balance is corrected. Emit green and blue colors.

A timer is provided for measuring the operation time of the PDP and outputting a signal each time the required time elapses, and the light emitting unit emits each of red, green and blue in response to a signal from the timer. Alternatively, an operation button for correcting the white balance of the PDP may be provided, and the light emitting unit may emit light based on the operation of the operation button.

Alternatively, the light emitting section is provided at a plurality of locations,
The sensor is provided in correspondence with each light emitting unit, and an average value calculating unit for calculating an average value of the luminance values of each color from each sensor is provided. May be compared with the reference luminance ratio read from the memory unit.

In addition, one of the light emitting units is configured to emit red, green and blue simultaneously, and the sensor separates the red, green and blue colors and measures the respective luminance values. Or one of the light emitting units is configured to sequentially emit red, green and blue colors at required time intervals, and the sensor is sequentially turned red at the light emitting unit light emitting time intervals. , Green and blue colors may be measured.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. FIG. 1 shows a PDP according to the present invention.
FIG. 3 is a block diagram of a main part of an embodiment of a white balance adjustment device of FIG.
In the figure, 1R, 1G, and 1B denote R, G, and B amplifiers that amplify video signals of each color of red (R), green (G), and blue (B), 2R, 2G, and 2B.
Is an RGB drive unit that drives the PDP 3 based on signals from the amplifiers 1R, 1G, and 1B, 4 is a video display area, and 5 is each of the red, green, and blue colors with the required brightness. , A sensor 6 that is provided in front of the light emitting unit 5 and measures the luminance value of each color of red, green, and blue, 7 is an amplifying unit that amplifies a signal from the sensor 6, and 8 is a white balance of the PDP 3. Memory section 9 for storing the reference luminance ratios of red, green and blue for each color, and compares the ratio of the luminance value of each color from the sensor 6 with the reference luminance ratio read from the memory section 8 and outputs a signal corresponding to the difference. A comparison unit 10 controls the amplification of the RGB amplification units 1R, 1G, and 1B based on the signal from the comparison unit 9. Reference numeral 11 denotes a control unit that controls the above units. FIG.
Is a front view of the main part of the PDP 3, and 5R, 5G, and 5B are light-emitting units (corresponding to the light-emitting unit 5) provided outside the image display area 4 and emitting red, green, and blue colors with required brightness. is there.

Next, the operation of the PDP white balance adjusting device according to the present invention will be described. The video signals of each color of red, green and blue are amplified by R, G, and B amplifiers 1R, 1G, and 1B.
The PDP 3 is driven via the B driving units 2R, 2G, and 2B, and an image is displayed on the image display area 4. Light emitting unit 5 (5R, 5G, 5B)
Emits red, green, and blue colors with required brightness irrespective of the image content of the image display area 4. These lights are measured by a sensor 6 disposed in front, and output a signal (brightness value) corresponding to brightness for each color. A signal corresponding to each color from the sensor 6 is amplified by the amplifying unit 7, input to the comparing unit 9 via the control unit 11, and read out from the memory unit 8 via the control unit 11 for red and green for white balance of the PDP 3. And a reference luminance ratio of each color of blue and blue, and outputs a signal corresponding to the difference. Based on this signal, the amplification control unit 10
Controls the amplification of the R, G, and B amplifiers 1R, 1G, and 1B,
The ratio of the luminance values of the red, green, and blue colors measured by the sensor 6 is set to the reference luminance ratio read from the memory unit 8.

The light emitting section 5 (5R, 5G, 5B) always emits red, green and blue colors, emits light only when white balance is corrected, or has a power supply. It may emit light when turned on to correct white balance. In addition, a timer is provided to measure the operation time of the PDP, and a signal is output each time the required time elapses. An operation button for correcting the balance may be provided, and the light emitting unit 5 may emit light by operating the operation button.

Alternatively, the light emitting units 5 (5R, 5G, 5B) are provided at a plurality of locations, the sensors 6 are provided corresponding to the respective light emitting units, and the average value of the luminance value of each color from each sensor 6 is calculated. A value calculation unit is provided to average out variations in luminous efficiency, and the comparison unit 9 compares the ratio of the average luminance value of each color from the average value calculation unit with the reference luminance ratio read from the memory unit 8. Is also good.

Further, one of the light emitting units (for example, FIG. 2)
5R), each color of red, green, and blue may be simultaneously emitted, and the sensor 6 may separate each color to measure the luminance value of each color, or one of the light emitting units may be used for a required time interval. , The red, green, and blue colors may be sequentially emitted, and the sensor 6 may sequentially measure the luminance values of the red, green, and blue colors at light emission time intervals of the light emitting unit.

[0014]

As described above, according to the present invention, P
According to the white balance adjusting device of DP, a light emitting unit that emits each color of red, green and blue is provided outside the image display area of the PDP, and the luminance value of each color from the light emitting unit is detected and compared with the white balance data. If there is a difference, the white balance is corrected by controlling the amplification degree of the video signal of a required color, so that manual white balance adjustment at the time of shipment from the factory becomes unnecessary, and the PDP changes with time. Deviation of the white balance caused by the white balance can be automatically corrected.

[Brief description of the drawings]

FIG. 1 is a main block diagram of an embodiment of a white balance adjusting device for a PDP according to the present invention.

FIG. 2 is a front view of a main part of an example of a PDP.

[Explanation of symbols]

 1R, 1G, 1B R / G / B amplifier 2R, 2G, 2B R / G / B driver 3 PDP 4 Video display area 5 Light emitting unit 5R, 5G, 5B R / G / B light emitting unit 6 Sensor 7 Amplifier 8 Memory unit 9 Comparison unit 10 Amplification control unit 11 Control unit

Claims (9)

[Claims] An image signal of each color of red, green and blue is red,
Amplifying in the amplifying unit for each color of green and blue, and driving the PDP via the driving unit for each color of red, green and blue, the respective colors of red, green and blue are displayed outside the image display area of the PDP. A light emitting unit that individually emits light at a required brightness is provided, and a sensor that is provided in front of the light emitting unit and measures the luminance value of each color of red, green, and blue, and a red, green, and white light for white balance of the PDP. A memory unit that stores a reference luminance ratio of each color of blue, a comparison unit that compares a ratio of luminance values of each color from the sensor with a reference luminance ratio read from the memory unit, and outputs a signal corresponding to a difference, An amplification control unit for controlling the amplification of the amplification unit for each color of red, green and blue is provided, and the amplification control unit controls red,
The amplification degree of the amplification unit for each color of green and blue is controlled for each color,
An apparatus for adjusting the white balance of a PDP, which corrects the deviation of the white balance due to variations of individual PDPs or changes over time. 2. The white balance adjusting device for a PDP according to claim 1, wherein the light emitting section constantly emits each color of red, green and blue. 3. The light-emitting unit emits red, green, and blue colors only when white balance is corrected.
A white balance adjusting device for a PDP as described in the above. 4. The PDP according to claim 1, wherein said light emitting section emits red, green and blue colors when a power is turned on.
White balance adjustment device. 5. A timer for measuring the operation time of the PDP and outputting a signal each time the required time elapses, wherein each of the red, green and blue light is emitted from the light emitting portion by a signal from the timer. Item 2. A white balance adjusting device for a PDP according to Item 1. 6. The white balance adjusting device for a PDP according to claim 1, further comprising an operation button for correcting a white balance of the PDP, wherein the light emitting unit emits light based on an operation of the operation button. 7. The light emitting section is provided at a plurality of locations, the sensor is provided in correspondence with each light emitting section, and an average value calculating section for calculating an average value of luminance values of each color from each sensor is provided. And comparing the ratio of the average luminance value of each color from the average value calculation unit with the reference luminance ratio read from the memory unit.
A white balance adjusting device for a PDP as described in the above. 8. One of the light emitting units is configured to simultaneously emit red, green, and blue colors, and the sensor separates each of the red, green, and blue colors and measures the respective luminance values. Claims 1, 2, 3, 4, 5,
6. The white balance adjusting device for a PDP according to 6 or 7. 9. One of the light-emitting portions is configured to sequentially emit red, green, and blue colors at required time intervals, and the sensor is configured to sequentially emit red, green, and blue light at the time intervals of light emission of the light-emitting portion. 8. The PDP according to claim 1, wherein the PDP is configured to measure luminance values of green and blue colors.
White balance adjustment device.