Patent ID: 7718938

Claim:
A spatial information detection system comprising: a plurality of detection devices, each of which comprises a light emitting source configured to project light intensity-modulated with a predetermined modulation period into a target space, a photodetector having a photosensitive portion configured to receive light from said target space to generate electric charges corresponding to a received light amount, and an evaluation portion configured to detect spatial information of said target space from a change between the light projected from said light emitting source and the light received by said photodetector; and a timing control portion configured to control timings of projecting the lights from said light emitting sources of said detection devices such that a light projection period of said light emitting source of one of said detection devices does not overlap with the light projection period of said light emitting source of another one of said detection devices, and to control said photodetector of each of said detection devices to have a light receiving period where said photosensitive portion receives the light from said target space in said light projection period to generate the electric charges, and a read-out period for taking out the electric charges generated at said photosensitive portion, which is set in at least one of said light projection period and a rest period where the light of said light emitting source is not projected into said target space, wherein said timing control portion is formed in each of said detection devices, and said timing control portion in one of said detection devices outputs a synchro signal to said timing control portion in another one of said detection devices at the end of said light projection period of said light emitting source in the one of said detection devices, so that said timing control portion which has received said synchro signal allows said light emitting source in the another one of said detection devices to initiate said light projection period.