| 摘要 |
A thin light-transmitting or light-diffusing plate is disposed opposite to a reflecting unit which has a Fresnel mirror reflecting surface made of a number of fine, sawtooth-shaped prisms in parallel, a reflecting surface made of a number of fine prisms in parallel arranged to form fine parallel ridges or a curved reflecting surface, said curve having characteristics appropriate to the purpose of the device, the light of a photoimage from a local light source is directed onto the reflecting surface of the reflecting unit, where it is reflected, and said reflected light in the incident state is uniformly distributed over the direction changing surface of the thin plate or is distributed over the surface in a predetermined pattern. The light incident to the diretion changing surface enables the surface to become a light emitting surface, a photoimage projecting surface or a surface which displays a photoimage. When the light propagating passage is reversed, solar light rays or other incident light can be converted. |
