Patent ID: 8736819
Filing Date: 2014-05-27
Classification: G01C,G01S

Abstract:
1. A distance measuring instrument, comprising a light emitting unit for emitting a distance measuring light, a photodetecting unit for receiving and detecting a reflected distance measuring light from an object to be measured and a part of the distance measuring light emitted from said light emitting unit as an internal reference light, a sensitivity adjusting unit for electrically adjusting photodetecting sensitivity of said photodetecting unit by adjusting a bias voltage impressed on said photodetecting unit, and a control arithmetic unit for calculating a measured distance based on a photodetection signal of the reflected distance measuring light from said photodetecting unit and based on a photodetection signal of the internal reference light, wherein said control arithmetic unit can measure a distance by selecting a prism mode measurement and a non-prism mode measurement, and said sensitivity adjusting unit controls the bias voltage so that photodetecting sensitivity distribution of said photodetecting unit is within the allowable error with respect to the selected measurement mode.