Abstract: A diffusion plate is used in a concentrator for solar light. By the diffusion plate, solar beams is evenly distributed on a solar cell. As a result, the whole solar cell can evenly receives the solar beams for energy transformation.

Abstract: A waveguide device used for a planar display device having an image source for emitting modulated light beams and a display panel for displaying an image. The waveguide device includes a slab waveguide having a light entrance plane and a light exit plane, a lens array comprising a plurality of lenses disposed in the form of a matrix for individually tuning and guiding corresponding modulated light beams to desired positions on the light entrance plane of the slab waveguide, a wedge waveguide for receiving modulated light beams emitted from the light exit plane of the slab waveguide and emitting the received modulated light beams to the display panel to form the image, and a fixing device for fixing the wedge waveguide to the slab waveguide.

Abstract: A circular display includes a columnar waveguide plate and an image projection device. The upper width of the cross-section of the columnar waveguide plate is less than the bottom width of the cross-section of the columnar waveguide plate. The outer surface of the columnar waveguide plate is utilized for displaying an image, and the image projection device is used for projecting the image to the bottom of the columnar waveguide plate.