Patent ID: 7409161

Claim:
A free space optics communication apparatus which performs communication with another apparatus with light beams, comprising: a plurality of light-emitting units, each of the units emitting a light beam which forms a generally elliptical irradiation pattern on a light-receiving unit of the other apparatus having a shorter diameter direction and a longer diameter direction, wherein the plurality of light-emitting units are set in such a way that an overlapping degree of irradiation patterns of light beams from at least two of the plurality of light-emitting units in the shorter diameter direction at the light-receiving unit of the other apparatus is adjusted, and thereby respective optical axes of the plurality of light-emitting units are inclined with different angles each other with respect to a reference axis of the free space optics communication apparatus so that a width of a combined irradiation pattern formed by combining the light beams from the plurality of light-emitting units is 1.5 times or larger than a width of the irradiation pattern formed by one light-emitting unit in the shorter diameter direction at the light-receiving unit of the other apparatus.