▲ Reflector
1. Metal reflector: it is generally made of aluminum and needs stamping, polishing, oxidation and other processes. It is easy to form, low cost, high temperature resistance and easy to be recognized by the industry.
2. Plastic reflector: it needs to be demoulded. It has high optical accuracy and no deformation memory. The cost is relatively high compared with metal, but its temperature resistance effect is not as good as metal cup.
Not all the light from the light source to the Reflector will go out again through refraction. This part of the light that has not been refracted is collectively referred to as the secondary spot in optics. The existence of the secondary spot has a visual easing effect.
▲ Lens
Reflector are classified, and lenses are also classified. Led lenses are divided into primary lenses and secondary lenses. The lens we generally call is the secondary lens by default, that is, it is closely combined with the LED light source. According to different requirements, different lenses can be used to achieve the desired optical effect.
PMMA (polymethylmethacrylate) and PC (polycarbonate) are the main circulating materials of LED lens in the market. The transmittance of PMMA is 93%, while PC is only about 88%. However, the latter has high temperature resistance, with a melting point of 135 °, while PMMA is only 90 °, so these two materials occupy the lens market with almost half advantages.
At present, the secondary lens on the market is generally total reflection design (TIR). The design of the lens penetrates and focuses on the front, and the conical surface can collect and reflect all the light on the side. When the two kinds of light are overlapped, a perfect light spot effect can be obtained. The efficiency of TIR lens is generally more than 90%, and the general beam angle is less than 60 °, which can be applied to lamps with small angle.
▲ Application recommendation
1. Downlight (wall lamp)
Lamps like downlights are generally installed on the wall of the corridor and are also one of the lamps closest to people’s eyes. If the light of the lamps is relatively strong, it is easy to show psychological and physiological incompatibility. Therefore, in downlight design, without special requirements, the effect of generally using Reflectors is better than that of lenses. After all, there is excessive secondary light spots, It won’t make people feel uncomfortable when walking in the corridor because the light intensity at a certain point is too strong.
2. Projection lamp (Spotlight)
Generally, the projection lamp is mainly used to illuminate something. It needs a certain range and light intensity. More importantly, it needs to clearly show the irradiated object in people’s field of vision. Therefore, this kind of lamp is mainly used for lighting and is far away from people’s eyes. Generally, it will not cause discomfort to people. In design, the use of lens will be better than Reflector. If it is used as a single light source, the effect of pinch Phil lens is better, After all, that range is not comparable to ordinary optical elements.
3. Wall washing lamp
Wall washing lamp is generally used to illuminate the wall, and there are many internal light sources. If a Reflector with strong secondary light spot is used, it is easy to cause people’s discomfort. Therefore, for lamps similar to wall washing lamp, the use of lens is better than Reflector.
4. Industrial and mining lamp
This is really a difficult product to choose. First of all, understand the application places of industrial and mining lamps, factories, highway toll stations, large shopping malls and other areas with large space, and many factors in this area can not be controlled. For example, the height and width are easy to interfere with the application of lamps. How to choose lenses or Reflectors for industrial and mining lamps?
In fact, the best way is to determine the height. For places with relatively low installation height and close to human eyes, Reflectors are recommended. For places with relatively high installation height, lenses are recommended. There is no other reason. Because the bottom is too close to the eye, it needs an excessive distance. The high is too far from the eye, and it needs a range.
Post time: May-25-2022
