JVC GD-V500PZU PLASMA TV Service Manual

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GD-V500PZU

2 Plasma Display Technology
2.1. Plasma display panel 2.3. Rear Glass Structure

Fig. C Fig. A

On the rear glass the data electrode is mounted. The dielectric is coated on the rear glass. Red, Green and Blue colour phosphors are formed on the data electrode with the ribs. However to improve colour reproduction and brightness, each colour phosphors are formed different width This is called " Asymmetrical cell " as JVC original technology.

JVC 42 inch wide plasma display panel is develope for large screen multimedia display with space saving. The plasma display panel use AC type Sub-field drive system with Dual scanning system. This panel have also JVC original Asymmetric cell and Plasma AI technology. Fig. A Is the CRT and Plasma Display Panel(PDP) comparison chart.

2.4.

Front Glass Structure

2.2.

Plasma display panel structure

Fig. D

On the front glass scan and sustain transparent electrodes are mounted in pair. The dielectrics is coated on the front grass. MgO over coat is also applied on the dielectrics.
Fig. B

Plasma display panel structure JVC Plasma display panel is consist of front glass, rear glass and Aluminum base. The front glass has each 768 lines scan and sustain transparence electrodes. The rear glass has 4098 (1366 x 3 ) data electrodes on the inner surface. These electrodes are connected to the data drive circuit boards directory.

The front and rear glasses are piled and sealed . And low presser gas are charged between two glasses.

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2.5.

Pixel Structure

2.7.

Initialization

Fig. E

50 inch plasma display panel has 1,049,088 pixels. Each pixels structure is shown fig. E.

Fig. G

To clear any remaining electric charge into the pixel, trapezoid voltage is applied between the scan and sustain electrodes. Plasma discharge is started but the discharge become small gradually. Then any electric charge is cleared.

2.6.

Sub Field Drive system

2.8.

Write

Fig. F

Brightness control of plasma display panel is carried out by plasma discharge time change. To control each pixelís brightness Sub-field drive system is used. A sub-field is consist of Initialize, Write and sustain operation.

Fig. H

Data Pulse which is positive polarity is input to data electrode and Scan pulse which is negative polarity is input to scan electrode simultaneously. That means sum of data and scan pulses voltage is applied between two electrodes as discharge start voltage. Discharge is started into the pixel and gas is ionized. During discharging Ion is charged on the scan electrode side and electron is charged on data electrode side.

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2.9.

Wall Voltage

2.11. Sustain Step 2

Fig. I

Fig. K

When input pulses are stopped, Ions and Electrons which are charged on the dielectric around the electrodes are remained. This charge is called Wall Voltage (Pilot voltage). This operation is called Write .

When sustain pulse is stopped, Ions and Electrons are remained again as Wall voltage. However polarity of wall voltage is reversed.

2.12. Sustain Step 3

2.10. Sustain Step 1

Fig. L Fig. J

Negative polarityís Sustain pulse is input between sustain and scan electrodes and voltage potential between two electrodes becomes sum of Sustain pulse and wall voltage. Then discharge start.

Positive polarity´s Sustain pulse is input between sustain and scan electrodes and discharge start again.

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