DISTANCE MEASURING INSTRUMENT AND DISTANCE MEASURING METHOD

PROBLEM TO BE SOLVED: To provide a distance measuring method for shortening a measuring time. SOLUTION: Before main measurement, preliminary measurement for far and near determination is carried out. In the preliminary measurement, a plurality of measurements are performed, a memory of a distance pin 4 is added on the basis of a counted value of a counting part 2 in each measurement to prepare a histogram as shown in (b). A far and near determination part determines whether a frequency is a determined frequency threshold n or more in a range of T1to Tpin the histogram. If it exists, a reflection light is obtained from a measured object existing at a near distance to set a near distance mode. If it does not exist, the measured object does not exist at the near distance to set a far distance mode. In the main measurement, at least one is differentiated out of the range used for determination of the maximum frequency in measurement times and the histogram in the near distance mode and the far distance mode. COPYRIGHT: (C)2007,JPO&INPIT