Abstract
A non-contact laser displacement meter based on the principle of optical triangulation is applied to measuring distance or displacement to an object and its shape. A laser diode is used as the light source and a position sensitive device as the light spot detector. A laser displacement meter of type MD-1211 with high accuracy has been developed, which is an intelligent equipment with a microprocessor. In this paper the errors caused by variable amount of receptive light and a light spot image on the position device are investigated. A control technique of laser output for type MD-1211 is proposed. In the new technique, the output intensity of the laser diode can be rapidly controlled within the range of 100 times of the minimum output by the microprocessor. A position sensitive device detects the center of light intensity on itelf. To reduce the error caused by diversion of the light spot, a device for design and adjustment of the receptive optical geometry is proposed. The overall structure and the specifications of type MD-1211 using the proposed techniques are described. Their usefulness are verified with several experimental results.
