To solve problems wherein light decoration spreading planarly is an effective light decoration method, wherein many LED lamps are embedded in a wall and ceiling surface, or a plurality of, so-called, lumitubes, which are formed by connecting the LED lamps at certain intervals in a beaded shape, are arrayed, but it requires many light sources such as LED lamps, and considerable cost is needed for wiring work or the like.

A plurality of refraction surfaces are arranged at a predetermined interval in an optical axis direction of the light sources such as the LED lamps. The planar light decoration system is efficiently achieved by utilizing an mirror image of the light source generated on each of the refraction surfaces.