Rangerfinder apparatus

A rangefinder apparatus comprising:

• light-projecting means for projecting a luminous flux toward an object at a distance to be measured;
• light-detecting means for detecting reflected light of the luminous flux projected toward the object at a light-detecting position on a position sensitive detector corresponding to the distance to the object, and outputting a signal corresponding to said light-detecting position;
• arithmetic means for carrying out an arithmetic operation according to the signal output from said light-detecting means, and outputting an output ratio signal corresponding to the distance to the object;
• integrating means for accumulating and integrating the output ratio signal, and outputting an integrated signal corresponding to integration of the output ratio signal;
• adjusting means for adjusting a period of each accumulating operation and the number of accumulating operations in said integrating means such that an integration time, a sum of respective periods of the accumulating operations, lies within a range including a fixed value;
• and
• detecting means for detecting the distance to the object according to the integrated signal output from said integrating means in conformity with a converting expression for a case where the integration time in said integrating means is at the fixed value.