The 3-D measurement is one of important techniques in the field of computer vision. In 3-D measurement using projection of spot lights, the information needed for acquiring 3-D positions is positions of the spot lights projected on the sensor plane. Lateral effect position sensitive photodetectors(LEP) are often used for position sensing. The LEP has problems in accuracy, linearity and effect of background illumination. Position sensing can also be achieved using imaging arrays such as CCDs. Higher resolution is needed to achieve higher accuracy using imaging arrays. However, the number of cycles needed to scan the entire image increases pro