Manufacturing of TFT backlighting

Manufacturing of TFT backlighting

1.Components of TFT backlight

1.1 LED beads

LED bead is the light source of the backlight module, usually adopts high brightness white LED. the main components of LED include LED chip, package material and gold wire connection. the LED chip is a semiconductor material, which is excited by current to produce light, while the package material protects the LED chip and dissipates heat.

1.2 Reflector

The reflector is located behind the LED bead and is used to reflect the light from the LED. Highly reflective materials such as aluminum or polycarbonate (PC) are often used to ensure that the light is reflected as much as possible and transferred to the light guide.

1.3 Light Guide Plate

A light guide plate sits between the LED beads and the LCD panel and is used to distribute the light evenly. It is usually made of optical-grade polycarbonate (PC) or polymethylmethacrylate (PMMA) material with microstructures on the surface to improve light uniformity.

1.4 Optical Sheet

The optical sheet is located on top of the light guide and is used to adjust the angle and brightness of the light. It usually includes diffractive, lens, and reflective sheets to optimize the display effect by changing the way light travels.

2.Manufacturing process

2.1 LED Mounting

The LED beads are firstly fixed on the FPC substrate of the backlight module, which is usually fixed with double-sided adhesive and ensures the accurate position of the LED beads and good heat dissipation.

2.2 Production and installation of light guide plate

The production of light guide plate includes the selection of raw materials, mold design, injection molding, surface treatment and other steps. After fabrication, the light guide plate is installed on the top of the LED beads to ensure that the light can be evenly transmitted to the entire TFT LCD.

2.3 Reflector Installation

Reflector plates are usually installed behind the LED beads to maximize light reflection. The mounting of the reflector plate needs to ensure alignment and tight fit with the LED beads to minimize light loss.

2.4 Optical Sheet Mounting

Finally, the optics are mounted on top of the light guide to optimize the display by adjusting the angle and brightness of the light. The mounting of the optics requires precise control of the position and angle to ensure the best visual effect.

3.Inspection Process

3.1 Optical Performance Inspection

During the manufacturing process, the backlight module needs to be tested for optical performance, including light uniformity, brightness consistency, color accuracy and so on. These tests are usually carried out by professional optical instruments to ensure that the display effect meets the requirements.

3.2 Brightness uniformity test

The brightness uniformity of the backlight module is crucial to the display effect. The inspection process usually adopts a photometer or camera to measure the light intensity distribution to ensure the brightness uniformity distribution of the whole display panel.

3.3 Color Uniformity Inspection

The color uniformity of the backlight module is also one of the important inspection indexes. Through professional color measuring instruments, the color performance of the backlight module in different positions is detected to ensure the uniformity and accuracy of the display colors.

3.4 Structural Stability Inspection

In addition to optical performance, the structural stability of the backlight module also needs to be tested. This includes tests on the heat resistance, humidity resistance, and mechanical strength of the backlight module to ensure its stability and reliability under different environmental conditions.

Through the above detailed manufacturing and inspection process, the backlight module can ensure good optical performance, brightness uniformity and color accuracy, thus providing a quality display.