| 摘要 |
The concentrator for a solar cell has a Fresnel lens (1) with stepped raised portions (3) on one or both sides embedded in a transparent layer (2) of plastics or glass. The refractive index of the glass is different from that of the lens. The lens can be a collector lens, its material having a higher refractive index than that of the material enclosing it. Two lenses may be used, one above the other, both embedded in the same material. Underneath the embedded lens are further layers (5,6,7) of plastics or glass, with the solar cell (8) at the bottom. The refractive index of these layers is lower than that of the lens. Their edges can slope inwards, so that the body of the concentrator slopes inwards towards the bottom. The top carries a coating (11) to reduce reflection. The plastics material may be acrylic glass. The whole unit may be shaped as a roof tile. |
