LCD/LCM Finished Product Inspection Requirements & Common Undesirable Phenomena

LCD/LCM Finished Product Inspection Requirements & Common Undesirable Phenomena

First of all, the inspection standard of liquid crystal is not yet involved in the national standard parameters, which are referred to the LCD industry quasi to meet the basic requirements of customers. a + aerospace, military grade products are more, the quality requirements are relatively high, the cost is also higher A industrial grade products are more, power systems, automotive instrumentation, electronic instruments, medical equipment, etc. B civilian products are more, air conditioning remote control, POS, washing machines, electric vehicles, the Higher cost control requirements. 

According to the quality requirements of different customers, the inspection standards will be different accordingly. 

Environmental requirements: 

LCD finished product inspection requires the use of two 40W fluorescent lamps, the inspector should be 1 meter away from the lamp. Ambient temperature control at 10 ~ 32 ℃, humidity control at 60 ± 15% RH. 

Inspection methods: 

1. inspection, the naked eye should be 30cm away from the LCD products. products should be in their correct display mode and drive conditions; 

2. LCD screen all-transparent products need to add backlight after checking the appearance under normal conditions; 

3. LCM light guide plate products must be tested once in the lit state appearance; 

4. where COG products in the SMD shall be checked after the telecommunications in the test frequency of 80HZ, the voltage needs to be adjusted in the range of 0.6V on the basis of Vop after 5 on the tester; 

5. TN products in the scanning state inspection: Leak, high current, the rest of the telecommunications project in the full display state inspection; 

Inspection level: 

the standard appears in the A, B, C for the product inspection level

A level is the most stringent, B level is the second, C level is looser. C level is looser. 

Different products applicable product inspection level, please refer to the technical department "product inspection specifications". 

Common Undesirable Phenomena

Common appearance defects are: black spots, white spots, dirt, scratches, internal scratches, pinholes, bad patch, external scratches, broken, glass residue, bad size, bad sealing, bad positioning, bubbles in the box, bad bezel adhesive, rainbow (but the area), bad bottom color, bad protective layer, bad PIN, bad silk screen, bad FPC, bad TCP, bad soldering, misalignment of capacitive parts, etc. 

Common functional defects are: Leak, Short, too much current, poor response, perspective defects, multi-display, display incomplete, word fat word thin, display color uneven, display black dot, white dot (within the visual area), backlight is not bright, dead light, etc. The following is a brief list of the criteria for taint.

LCD module of all raw materials are a life limit, which is why there are uneven prices on the market, such as an LCD module chip life in 80,000 hours, but it should be noted that this 80,000 hours refers to the IC in its factory, must be within one year of the production date to ensure that it reaches its life span, if not its life time is affected of.

The above is the basic inspection standards of our LCD industry, in the daily negotiations must be good communication between the two sides, side to their follow-up work inconvenience!

Liquid crystal has a complete quality system, each piece of liquid crystal screen factory will go through a strict 72-hour aging, the company is equipped with a high and low temperature shock box, electrostatic tester, salt spray test box, drop tester, high frequency vibration table, voltage impactor and a series of test tools, so you can rest assured that use!