Patent ID: 6472652
Filing Date: 2002-10-29
Classification: G01C

Abstract:
A distance measuring apparatus comprising:light projecting means for projecting a light beam toward an object at a distance to be measured, multiple times; light detecting means for detecting light of the light beam reflected from the object, at a reception position according to the distance to the object and outputting a far signal, which increases with an increase in the distance, and a near signal, which increases with a decrease in the distance; clamping means for comparing the far signal with a preset clamp signal, outputting the far signal when the far signal is not less than the clamp signal, and outputting the clamp signal when the far signal is smaller than the clamp signal; calculating means for calculating a ratio of the near signal and the signal output from said clamping means and outputting an output ratio signal; output signal detecting means for detecting whether the signal output from said clamping means is the far signal or the clamp signal; integrating means for accumulating the output ratio signal for every emission of the light beam from said light projecting means to perform an integration and outputting an integral signal according to the integration; and transforming means for transforming the integral signal to a distance signal according to the distance, in accordance with transformation equations based on the detecting by said output signal detecting means.