PURPOSE: To provide a flat light emitter which is applicable even to a flexible and irregular surface.

CONSTITUTION: A flat emitter 10 formed with a flexible base material 11, numbers of photoconductors 12 planely provided in parallel to one face of the base material 11 and a light diffusion material 13 to cover the photoconductors 12, is freely bend by its own flexibility and applicable to a flexible and irregular surface. For the flat emitter 10, it light is injected from a light source to the end face of each photoconductor 12, then the light propagates into each photoconductor 12 and is emitted from the side face to the outside. The emitted light is injected to the light diffusion material 13 directly or in reflection from the reflecting material 11a and emitted to the outside via a surface material 13 so that the flat emitter 10 may be illuminated at the lower part. In this case, as the light emitted from each photoconductor 12 is diffused to the facial direction inside the light diffusion material 13, wholly uniform flat light emittion is obtained without causing stripes corresponding to each photoconductor 12.