Tech Support- Handling LCD

Liquid Crystal Display(LCD)

A LCD is made up of glass, organic sealant, organic fluid and polymer based polarizers. The following precautions should be taken when handling:

1. Keep the temperature within range for use and storage. Excessive temperature and humidity could cause polarization degradation, polarizer peel-off or bubble generation. When storage for a long period over 40°C is required, the relative humidity should be kept below 60%.
2. Do not contact the exposed polarizers with anything harder than an HB pencil. To clean dust off the display surface, wipe gently with cotton, chamois or other soft material soaked in petroleum benzine. Never scrub hard.
3. Wipe off saliva or water drops immediately. Contact with water over a long period of time may cause polarizer deformation or color fading, while an active LCD with water condensation on its surface will cause corrosion of ITO elctrodes.
4. Petroleum Benzine is recommended to remove adhesives used to attach front/rear polarizer and reflectors, while chemicals like acetone, toluene,ethanol and isopropyl alcohol will cause damage to the polarizer. Avoid oil and fats. Avoid lacquer and epoxies which might contain solvents and hardeners to cause electrode erosion. Some solvents will also soften the epoxy covering the pins and thereby weaken the adhesion of the epoxy on glass. This will cause the exposed electrodes to erode electro-chemically when operating in high humidity and condensing environment.
5. Glass can be easily chipped or cracked from rough handling, especially at corners and edges.
6. Do not drive LCD with DC voltage. It will damage the LCD.
7. When soldering DIL pins, avoid excessive heat and keep soldering temperature between 260°C and 300°C for no more than 5 seconds.

Operation

• The viewing angle can be adjusted by varying the LCD driving voltage.
• Driving voltage should be kept within specified range, excess voltage shortens display life.
• Response time increases with decerase in temperature.
• Display may turn black or dark blue at temperatures above its operating range, however, this is not destructive and the display will return to normal once the temperature falls back to range.
• Mechanical disturbance during operation (such as pressing on the viewing area) may cause the segments to appear "fractured". They will recover once the display is turned off.
• Condensation at terminals will cause malfunction and possible electro-chemical reaction. Relative humidity of the environment should therefore be kept below 60%.

Storage

1. Store LCDs and modules in dark places and do not expose to sunlight or fluorescent light. Keep the temperature between 0°C to 35°C and the relative humidity low.
2. Modules should be kept in antistatic packaging. If properly sealed, there is no need for desiccant.

Safety

• If any fluid leaks out of a damaged glass cell, wash off with soap and water any human part that comes into contact with the fluid. Never swallow the fluid. The toxicity is extremely low but caution should be exercised at all times.