LED screen backlight, straight down and side entry, what's the difference? The forms of light?
The side light type backlight source is a light source made of linear or point light source on the side of specially designed light guide plate. The light guide plate is the use of the principle of the light guide plate acrylic (PMMA) at the end of the distribution network (pattern) interference phenomenon of light damage, the uniform line source into surface light, its function is to guide the direction of light scattering, let the light distribution more uniform so that from the front can not see the shadow of the reflection point, to improve the panel the brightness, and ensure the uniformity of the brightness of the panel, has excellent effect on the backlight light guide plate, light guide plate according to the actual needs of the use, and can be made into bilateral type, three edge type and four type. The backlight can be very thin, but the backlight light utilization rate is low, and the thinner the utilization rate is small, its core technology is the design and manufacture of the light guide plate, is the main form printing and injection molding two shaped light guide plate form, such as injection molding and printing, laser, corrosion accounted for a small proportion, not suitable for mass production principles. The printing form because of its low cost has become the mainstream technology in the past a long time, but quality is not high has been the main faults, and the current LCD product requirements guide plate structure more precise, injection molding shaped light guide plate backlight will inevitably become the mainstream of development, but the mold related technical issues only a few companies were able to overcome. With the development and maturity of the light guide panel technology, the side led LED backlight LCD TV can really adapt to the ultra-thin development trend of lcd.
Side light LED backlightIn the side light source, LED is distributed on the side of the light guide plate, and the structure is compact.
The side light type LED backlight application in large size LCD, light weight and cost will increase with the increase in size, and the brightness and uniformity is not ideal, and side light type LED backlight LCD TV because of the light guide plate can not realize the regional dynamic LCD TV control, can only achieve a simple one-dimensional dimming, and direct type LED backlight performance is relatively good, it can achieve the dynamic control of LCD tv. Direct type backlight source process is relatively simple, does not need the light guide plate, the light source is (LED chip array) and PCB in the backlight bottom, light emitted from the LED, through the reflection sheet at the bottom, then through the diffusion plate, the surface brightness enhancement film evenly emitting. The thickness of the backlight is mainly determined by the height of the cavity between the reflecting film and the scattering plate. In theory, the greater the height of the cavity, the better the uniformity of light emitted from the scatter plate in the light of the installation requirements and brightness.
