Specific Service Instructions - JVC LT-32SH6/A Service Manual

Lcd flat television

Table of Contents

2.1

ABOUT LIQUID CRYSTAL DISPLAY

2.1.1 STRUCTURE OF LIQUID CRYSTAL PANEL

The Liquid Crystal Display used for this unit is of a TFT (Thin Film Transistor) type panel. The structure of this panel is that a TFT

array-formed substrate and the stripe pixel matrix type color filter substrate are pressed together with a liquid crystal filled in between

these materials.

2.1.2 LONG-TERM AFTERIMAGE ON THE LCD

A minute amount of ionic material could be mingled into a liquid crystal substrate in the manufacturing process. By applying the

electricity to the panel the ionic material may be migrated towards one part of the electrodes, causing a long-term afterimage to be

displayed. In practice, when a still image is displayed for a long time, the afterimage may be developed and persisted. To cure this

problem, turn off the unit and then turn on again and arrange displaying an appropriate still image on the portion where the afterimage

is being superimposed.

2.1.3 RESPONSE SPEED OF THE LCD

The LCD is slower than the CRT in terms of the display refresh rate, causing a fast moving picture may be displayed blurred. This is

not fault but caused by an intrinsic characteristic of the LCD.

2.1.4 VIEWING ANGLE OF THE LCD

This LCD uses a wide-angle liquid crystal panel, featuring a low rate of the brightness inversion. When viewed from a far outer angle,

the screen may be displayed with hue variation. Again, this is not fault but caused by an intrinsic characteristic of the LCD.

2.1.5 PIXEL DEFICIENCY OF THE LCD

The liquid crystal panel is manufactured with precise engineering procedure. However, there is a possibility of yielding a little amount

of defective pixels in part on the panel. This is unavoidable feature even if the latest technology is being used for manufacturing the

LCD module.

2.2

IMPORTANT NOTICE WHEN REPLACING COMPONENT PARTS

2.2.1 REPLACING THE LCD MODULE

(1) The LCD panel is fragile against the static charge. Be sure to take an appropriate grounding using a grounding-strap etc. when

to replace the LCD panel.

(2) The LCD is made of glass, which is fragile against the mechanical shock. Use utmost care when handling the LCD panel.

(3) When replacing the panel, first place the panel on the base chassis and then make sure that there is no gap in between the panel

and the chassis. Fix the panel with fixing screws. Turn the unit on with an all-black signal being put in and check if the brightness

is even on the entire screen. If the brightness is not even in some part, slacken the fixing screw nearby until the brightness

becomes even with other parts.

(4) A tightening torque for the fixing screws must be set to 0.294Nm or the less. Applying the torque larger than this limit may result

in the damage on the LCD panel.

(5) Connecting or disconnecting the plugs with the set is being powered may cause the malfunction of the set. Makes sure that the

AC power plug is disconnected from the power source when attempting the replacement work.

2.2.2 REPLACING THE FUSE

Be sure to use the rated fuse. After replacing the fuse, confirm that the insulator is stuck on the shielding surface for secure insulation.

SECTION 2