Patent ID: 6760547
Filing Date: 2004-07-06
Classification: G03B

Abstract:
A rangefinder apparatus comprising:autofocus (AF) data generating means for forming an image of light from an object at a distance to be determined by rangefinding onto a pair of line sensors, each line sensor including a plurality of light detecting elements, and generating AF data for computing a correlation value according to signals produced by the light-detecting elements; AF data acquiring means for acquiring the AF data from a pair of sensor areas used for the rangefinding and respectively within the pair of line sensors; correlation value computing means for determining a pair of window areas for selecting the AF data to be used for computing the correlation value within the pair of sensor areas, and successively computing correlation values while shifting the pair of window areas; interpolated correlation extreme value computing means for detecting correlation extreme values, among the correlation values computed by the correlation value computing means, and interpolating the correlation extreme values to compute interpolated correlation extreme values; highest correlation value detecting means for detecting as a highest correlation value the interpolated correlation extreme value exhibiting the highest correlation, among the interpolated correlation extreme values; shift amount computing means for computing a shift amount of the window areas yielding the highest correlation value; and object distance calculating means for calculating the distance to the object according to the shift amount computed by the shift amount computing means.