We know that LED optical lenses are generally divided into "primary lens" and "secondary lens". The "lens" often referred to by the manufacturers of outdoor lighting lamps and lanterns mostly refers to the "secondary lens" connected to the outside of the light source. The primary lens actually refers to the light source itself, and we will focus on it below: "secondary lens" is abbreviated as "lens".

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.

The characteristics of LED wall washer silicone sealant are as follows:

(1) Non-melting type, low shrinkage.

(2) Excellent elasticity and good sealing effect.

(3) Wide operating temperature range and continuous high temperature resistance.

(4) Excellent weather resistance, can withstand the environment of wind, rain, frost, sun, and ozone for a long time, without degradation, hardening of stones, no brittleness, and little change in force generation.

(5) Excellent electrical properties, showing good dielectric properties when used in the electronic field, and being waterproof, moisture-proof, and anti-corrosion, which can effectively seal and insulate various electronic components and equipment.

(6) Excellent chemical stability, long-term resistance to most chemicals, lubricants and some solvents.

(7) Non-flammable lamps, self-extinguishing away from the fire.

(8) Dust will accumulate due to static electricity.