To provide a lens/diffuser switching device which is capable of making electrical switching between an optical element state and a diffuser state.

This lens/diffuser switching device includes the optical elements constituted to form optical images cooperatively with the light directed to the device and a polymer dispersed liquid crystal material layer having a transparent state and a diffused state. The polymer dispersed liquid crystal material layer 35 is arranged together with the optical elements in such a manner that the optical elements form the optical images when the polymer dispersed liquid crystal material layer 35 is in the transparent state and that the polymer dispersed liquid crystal material layer 35 acts as a diffusion screen and forms the images together with the light directed thereto in the diffused state.