Inspection Process for TFT-LCD Module

The inspection of TFT-LCD Module engineering is the pre-shipment check of the product, involving a comprehensive examination of the entire product. Through product inspection in module engineering, the inflow of defective products into the market is prevented. Different factories have different inspection processes for module engineering. The process includes the following steps:

 

After voltage adjustment and high-temperature aging, the display inspection is carried out first. When display defects are detected, the general type of defect is noted, and it is handed over to analysts for further analysis and confirmation. Defective phenomena can be classified into several types: line defects, pixel defects, uneven display, flickering, grayscale defects, crosstalk, ripple, display misalignment, foreign objects on display, display anomalies, and image retention.

 

The electrical characteristics inspection includes power supply current, power supply variation, and additional functions. The specific steps involve applying a voltage to the module product to put it in a display state, measuring the current value, changing the applied voltage, and switching additional functions (such as the screen inversion function) to observe if the screen changes according to the specifications.

 

The optical characteristics inspection involves measuring brightness, contrast, brightness uniformity, and chromaticity using a color luminance meter. Typically, 9 points are tested. Brightness non-uniformity refers to the ratio of maximum brightness to minimum brightness measured at specified points.

 

The visual inspection includes defects that affect visual effects, such as foreign objects, scratches, bubbles, label content and placement, assembly status, and component deficiencies. Generally, defects like TAB line defects, foreign objects in the backlight source, and assembly defects are the most unacceptable to users.

Foreign objects are observed using a magnifying glass, and the observation angle is changed. If the foreign object changes with the observation angle, it may be on the TFT polarizer or the emitting surface of the backlight source, which can only be determined after disassembly.

If the foreign object does not change with the observation angle, it is likely within the display screen. When observing scratches or bubbles on the polarizer, no electrical connections are made. If scratches or bubbles are found, the polarizer needs to be replaced, the label needs to be checked for correct placement, and the assembly condition needs to be inspected, mainly focusing on the state of screw fitting and the stability of the backlight source's CCFL. After the visual inspection, qualified products can be packaged and stored.

In addition to the mentioned inspection items, random sampling is also performed before product shipment. The purpose of random sampling is to ensure product quality and prevent defective products from reaching customers. Along with the same inspection items as product inspection, there are also size inspections, optical characteristics inspections, and more.

 

If you need to purchase our TFT-LCD Module, you can contact us at sales@innoluxlcdpanel.com