Glass-based silicon large Fresnel lens, can be used for solar concentrator.
1. Advantages: Fresnel lens is a flat condenser, light weight, the price is relatively low, but also a little focus and line focus of the points, generally made of plexiglass or other transparent plastic, but also useful glass, mainly used for Condenser solar cell power generation system. China from the 1970s to the 1990s, the use of solar devices for Fresnel lens developed. A large area of flexible transparent plastic Fresnel lens can be processed by molding method, and point-focusing Fresnel lens with 1.5m diameter can also be processed by combination molding tool. Recently, a linear glass Fresnel lens has been processed by a molding method.
2. Disadvantages: due to lack of precision, condenser effect still need to improve.
In addition, there are two new reflections using the principle of the new solar concentrator, although not yet practical application, but has a certain inspiration. One is an optical fiber condenser, which consists of an optical fiber lens and an optical fiber connected thereto. The sunlight is focused by the fiber lens and transmitted from the optical fiber to the use. The other is a fluorescent condenser, which is actually a transparent plate (usually plexiglass) that adds fluorescent pigments that absorbs the portion of the sun that coincides with the wavelength of the fluorescence absorption band and then grows longer than the absorption band The emission band wavelengths emit fluorescence. The emitted fluorescence is guided to the edge of the plate in a totally reflective manner due to the difference between the plate and the surrounding medium, and its concentrating ratio depends on the ratio of the area of the plate and the area of the edge, which is easy to reach between 10 and 100 The different directions of the incident light can absorb, but also absorb the scattered light, do not need to track the sun.