Lens is an optical element whose surface is part of a spherical surface made of transparent materials (such as glass, crystal, plastic, etc.) according to the laws of light refraction and reflection. The LED secondary optical lens is to redistribute the lamp beads and the patch light source
Common lenses have the following materials:
(1) Silicone lens: The small-volume silicone lens has high heat resistance and can be reflowed, so it is often used in the LED packaging industry.
(2) PMMA lens: PMMA lens is the commonly used lens for high-power wall washers that we are talking about today, and it is also called by the industry: "acrylic optical lens". Its main feature is that the light transmission performance can reach more than 90%, compared with silica gel. The temperature resistance of the lens is slightly weak, and the working temperature cannot exceed 80 degrees Celsius.
(3) PC lens: The PC lens, which is also an optical lens, has a light transmittance of about 10% lower than that of a PMMA lens, but its thermal change temperature is more than 45% higher than that of a PMMA lens.
(4) Glass lens: The glass lens can be said to be the most expensive one of the above types of lenses, because the equipment for producing this type of lens is quite expensive. Although the light transmission performance can reach more than 97%, everyone knows that the glass material is Fragile materials, so glass lenses are rarely used as optical lenses for lighting fixtures on the market.