Many LED injection molding modules use lenses to make the light spot more uniform, and projecting onto the canvas can avoid dark areas and bone inscriptions, making the picture more beautiful. In order to understand these problems, we need to understand the principle of the lens.

The LED lens is divided into a primary lens and a secondary lens.

primary lens

a. The primary lens is directly encapsulated (or glued) on the LED chip holder and integrated with the LED.

b. The LED chip (chip) theoretically emits light at 360 degrees, but in fact the chip is fixed and packaged on the LED bracket, so the maximum light-emitting angle of the chip is 180 degrees (there is also a small amount of residual light in the range greater than 180°). There will also be some stray light rays, so that all the light rays of the chip can be effectively converged through one lens and different light exit angles such as 180°, 160°, 140°, 120°, 90°, 60°, etc. can be obtained, but different There are certain differences in the light-emitting efficiency of LEDs with light-emitting angle (the general rule is: the larger the angle, the higher the efficiency).

c. The primary lens is generally made of PMMA, PC, optical glass, silica gel and other materials.

Secondary lens

a. The secondary lens and the LED are two separate objects, but they are inseparable in application.

b. The function of the secondary lens is to refocus the light-emitting angle of the LED light source into any desired angle between 5° and 160°. The distribution of the light field can be mainly divided into: circle, ellipse, and rectangle.

c. The secondary lens material is generally optical grade PMMA or PC; in special cases, glass can be selected.