Various Cutting materials- Backlight Source Knowledge Analysis

Today I would like to introduce a type of cutting material - backlight source, which is an optical component that provides backlight for LCD display products. Since the LCD glass itself does not have luminous characteristics, a backlight, called a backlight source, is added to the back of the LCD glass as needed. The application range includes industrial equipment, bank terminals, office automation, communication, electronic toys, and consumer products.

Backlight Source Classification:

Currently, there are three types of backlight sources: EL, CCFL, and LED. According to the distribution of the light source, it can be divided into edge-lit type and direct type (bottom backlight type).

Here is a brief introduction:

◆ Edge-lit type: Linear or point light sources are placed at the specially designed light guide plate on the side of the backlight source. According to actual needs, it can be divided into double-sided or even three-sided. The edge-lit backlight source is generally very thin, but the light utilization efficiency of the light source is low, and the thinner it is, the lower the utilization efficiency, at most about 50%. The technical core lies in the design and manufacturing of the light guide plate, and the most commonly used side lighting types are LED backlight and CCFL backlight.

◆ LED backlight: LED, also known as Light Emitting Diode. Compared with other light sources, single LED has the smallest power consumption. LED comes in various colors, from blue to red. Since white is a mixed color, it does not have a discernible wavelength value, so its coordinates are used to represent it on the chromaticity diagram. We call it "cold white" and "warm white". There is color deviation in various colors, among which blue and white are more obvious, especially white.

◆ CCFL backlight: The biggest advantage of this backlight source is high brightness, which is basically suitable for black and white negative phase, blue mode negative phase, and large-area color LCD devices. Theoretically, it can produce various colors based on the color matching principle of the three primary colors. The disadvantage is high power consumption, requiring inverter circuit drive, and narrow working temperature range between 0 and 60 degrees Celsius, while other backlights like LED can reach -20 to 70 degrees Celsius.

◆ Bottom backlight type: It is a planar light source with a certain structure, which can be a continuous and uniform surface light source, such as EL or flat fluorescent lamp; or it can be composed of multiple points, such as dot matrix LED or incandescent backlight. Dot matrix LED and EL backlight source are commonly used.

◆ EL backlight source: Electroluminescence is a cold light source that excites the fluorescent powder to emit light through an alternating electric field. Its biggest advantage is thinness, which can reach a thickness of 0.2-0.6mm. The disadvantages are low brightness, short lifespan (generally 3000-5000 hours), inverter drive, flicker, and noise caused by circuit interference. EL is driven by an inverter and a driver chip.

◆ LED backlight: Good brightness and uniformity. The disadvantages are thickness (greater than 4.0mm), the use of multiple LEDs, and obvious heating phenomenon. Generally, low brightness colors are used in design, but due to higher costs, high brightness colors are not considered.

The production process of backlight sources is very complicated, and each step has stricter requirements, especially the control of the cutting process. Only high-quality cutting machines can produce high-quality products and reduce waste to some extent, saving costs. If you want to learn more about technical issues related to cutting production or need assistance in selecting a circular knife cutting machine, please feel free to contact IndustryProcess, Fumart is always ready to serve you.