III. Optical materials and technology
3.1 Advantages and disadvantages: PC VS. Acrylic
PMMA, scientific name polymethyl methacrylate, commonly known as acrylic. This material has a relatively high light transmittance,
The penetration rate is about 93% when the thickness is 3MM. However, it cannot withstand high temperatures. The temperature should not exceed 80 degrees, and thermal deformation will occur at 92 degrees. Furthermore, with the increase of use time and ultraviolet radiation, yellowing will occur, the lens Slowly turns yellow and transmittance decreases. Therefore, PMMA lenses are usually used indoors.
PC, scientific name polycarbonate. The light transmittance of this material is slightly lower than that of PMMA, and the transmittance is about 89% when the thickness is 3MM. But it can withstand high temperature than PMMA, the thermal deformation temperature is 135 degrees, and it is resistant to yellowing. Therefore, when outdoors PC lens should be used.
3.2 Advantages and disadvantages of reflective cup processing technology
At present, the mainstream reflector is an aluminum spinning reflector, the surface is anodized or vacuums electroplated. This
This kind of reflector cup is simple to process and adopts aluminum sheet spinning forming. The unit price of mold and product is relatively cheap, but there are restrictions on the surface shape of the reflector cup, and the accuracy is not as high as that of the injection-molded ABS reflector cup. The reflectivity of anodizing treatment is about 80%, and the service life is longer, which can reach 3-5 years; the reflectivity of vacuum plating can reach 90%, but the service life is relatively short about two years. Therefore, anodizing treatment is usually used.
As for ABS reflectors, after injection molding and vacuum plating, the unit price of molds and products will be more expensive than aluminum spinning reflectors, so aluminum spinning products are generally used.
For non-rotationally symmetrical reflector cups, it can be vacuum electroplated after injection molding. Alternatively, the aluminum reflector can be stamped, but the accuracy is not high.
3.3 Application of reflective film and light guide plate in LED lamps
The technical level of reflective film is getting higher and higher, and its reflectivity has reached 90%. More and more lamps like to use reflective film to achieve the comfort of indirect lighting. Its light effect is also the same as that of lamps using diffusers. quite. In addition, the reflective film can be used as an auxiliary part of the lamp, which can be attached to the lamp to improve the light extraction efficiency. Light guide plates are currently mainly used in side-emitting lamps, such as panel lights, side-emitting downlights, etc.
IV. What help can optical engineers provide to R&D personnel?
- Provide R&D engineers with inquiries and answers on optical design related issues;
- During product development, provide R&D engineers with reasonable optical solutions to solve optical problems encountered in the process;
- Import qualified outsourcing lenses and reflectors, etc., to provide a wealth of optical solutions for the research and development of lamps;
- Improve the optical design platform to provide engineers with more convenient and quick query methods and more accurate information;
- Focus on cutting-edge knowledge and technology related to optical design and optical processing, and provide researchers with quite advanced optical solutions.