A smart position sensor for 3-D measurement has been developed. The sensor is designed for detecting positions of laser spots projected on target objects quickly. The sensor has a 256×256 pixel array, a set of address decoders for variable block access and a variable block logical-OR circuit on an 8.9mm×8.9mm die. The sensor is designed and fabricated in 0.6µm CMOS 3-metal 2-poly-Si process. The measured accuracy of 3-D measurement is 0.4%. The speed of 3-D measurement is up to 10000points/s.