An inexpensive real-time 3-D camera with a smart optical sensor

A 3-D camera has been developed, capable of measuring 50 complete depth images per second of arbitrary, diffusely reflecting objects. The output of this real-time 3-D camera is a CCIR video signal, in which the depth is linearly coded as the local gray-value of the video image. The measurement principle is active triangulation using a solid-state laser and two galvanometer mirrors for beam and scene scanning. No complicated electronics or computers are required because the essential ‘calculations’ (centre-of-gravity of light profiles) are carried out purely optically with a special sensor consisting of wedge pixels. The use of this smart sensor makes the 3-D video camera relatively inexpensive, and the output in video-format allows the connection with any standard video framestore for direct 3-D image processing. It is concluded that this development can be of appreciable practical interest for many applications in industry.