Car headlights lampshades usually use the following common materials:

1. Glass: Glass is a common lampshade material in car headlights, which has high light transmittance and heat resistance. Glass lampshade can provide clear light transmission effect, and has good scratch resistance and wear resistance. However, the glass lampshade is relatively heavy and fragile, which requires extra protective measures.

2. Plastic: Plastic is another common lampshade material in car headlights, and high-strength plastics such as polycarbonate (PC) or polymethylmethacrylate (PMMA) are usually used. Plastic lampshades have the characteristics of light weight, good impact resistance and formability, and the price is relatively low. However, plastic lampshades are susceptible to ultraviolet rays and chemicals, and are prone to aging and discoloration.

3. Resin: Resin is a new type of car headlights lampshade material, which has excellent optical properties and aging resistance. Resin lampshades are usually made of optical grade polycarbonate (PC) or polystyrene (PS), which can provide clear and uniform light transmission effect, and have good weather resistance and ultraviolet resistance.

4. Silica gel: Silica gel is a soft, high-temperature resistant material, which is commonly used for sealing rings and waterproof covers in car headlights. Silica gel has good heat resistance and weather resistance, which can effectively prevent water vapor and dust from entering the interior of lamps and protect bulbs and circuit systems.

To sum up, the common materials of lampshades in car headlights include glass, plastic, resin and silica gel. Lampshades made of different materials have their own characteristics and applicable scenarios, and consumers can choose suitable materials according to their needs and budgets.