Patent ID: 8064772

Claim:
A wavelength multiplexing optical space transmitter for multiplexing optical signals having a plurality of wavelengths and transmitting the multiplexed optical signal via a free space, the transmitter comprising: a plurality of light sources for outputting lights each having a different wavelength, the plurality of light sources being arranged so as to provide a spatial area through which each of the lights pass; and a reflective type diffusion plate arranged such that at least a part of a surface thereof intersects the spatial area, for generating a diffuse light by reflecting and diffusing each of the lights entering from the plurality of light sources such that optical axes of the lights agree with each other, and for radiating the diffuse light as a multiplexed optical signal into the free space, wherein each of the plurality of light sources includes a light emitting element and a light source lens for converting an output light from the light emitting element into a substantially parallel light, wherein the wavelength multiplexing optical space transmitter further comprises a radiation lens provided separate from the reflective type diffusion plate, the radiation lens adjusting a spread angle of the diffuse light that enters the radiation lens, and wherein the radiation lens and the light source lens of each of the plurality of light sources are formed in one piece.