1. To prevent excessive pressure: LCD welding to the circuit board, LCD pin in principle should not be stressed in principle, otherwise it will cause bad contact. If it is necessary to be forced, it is necessary to design a supporting foot that does not need to be conductive, or to use elastic special-shaped feet, or to use hard glue to fix it.
2. Precautions for welding: 1) the distance from the glass bottom to the PCB welding position should not be lower than 5MM, and the limit should not be less than 2MM. The welding temperature is not higher than 260 DEG C, otherwise the LCD screen by the thermal impact caused by molecular arrangement chaos black reggie. When the welding temperature reaches 350 degrees centigrade, it is possible to produce a large proportion of black spots after welding. And the welding time is not more than 5 seconds, so as not to burn yellow. 2) Try not to force the foot of the pipe after welding, so as to avoid bad contact. If the position of LCD substrate or tube must be adjusted, it should wait until the foot of the tube is cooled to room temperature, and the LCD should not be wrenched when it has not been cooled. 3) When welding LCD, the welder should wear a finger sleeve or glove to prevent the hand from perspiration to corrode the metal foot.
3. After the assembly is finished, the protective film on the polarizer must be removed.
4. Device moisture-proof: 1) because LCD is low voltage and micro power, the resistivity of liquid crystal material is very high, up to 10000 Mega. Therefore, the small conductivity of the glass surface due to humidity will affect the display. 2) It is strictly forbidden to condense the water vapor on the surface of the display screen. The water droplets are condensed on the surface of the display screen, which will cause the rapid hydrolysis of the polarizer. The edge corner will rapidly decompose and spread to the center, which can not be displayed.
5. To prevent scratch: because the LCD surface is a polarizer, belongs to the plastic category, so the assembly and use should absolutely avoid hard scratching. There is a layer of protective film on the surface polarizer of LCD, and there is no protective film on the surface of LCD without backlight, especially easily scratched.
6. To prevent the application of DC power: the smaller the DC component of drive voltage is, the better the best is no more than 50mV or 1%. Too long DC components will cause the liquid crystal to decompose and make the electrode produce electrochemical reaction and aging. The two frequency division circuit is often introduced in the oscillating circuit to ensure the symmetry of the square wave.
7. Anti ultraviolet: all LCD screens in our company have the anti UV function.
8. Use and store in the specified temperature range. Because the liquid crystal state will disappear after a certain temperature range, it must be used and stored in the specified temperature range. The temperature is too high, the liquid crystal display is disappeared into a liquid, black, can not work. Don't use electricity at this time. When the temperature is restored to normal, the display surface will be restored to normal. If the temperature is too low, the liquid crystal state will disappear and the ice becomes crystal. At this point, it is possible to destroy the directional layer in the process of forming the crystal and cause permanent damage.
9. Prevent static interference: because the LCD working voltage is very low, the internal resistance is very large, very little static electricity can cause display. So try not to put LCD in a static environment. If you can't avoid, it should be anti-static line inside the LCD design, accelerate the communication speed scraper or driver, to eliminate static electricity.
10. Molecular diffusion phenomenon: if the LCD screen for a long period of time is three to five years, showing a fixed content, it will form a molecular diffusion phenomenon, that is, there is a distinct word shadow in the display area. It is suggested that the program control let the LCD screen rest or refresh intermittently to avoid holding the fixed position for too long to cause damage.
11. Low temperature response speed: the lower the temperature, the higher the viscosity of the liquid crystal material, the slower the response speed and the longer the response time. When the temperature is 10, the response time will be extended by 3 times. Response time = rise time + drop time. When working at low temperature, the refresh time of the driver's data should be greater than the response time of the LCD screen to ensure the normal display of the LCD screen