1. A distance measuring device comprising: a distance measuring sensor for measuring a plurality of regions of an object region and outputting measurement data; a detector for detecting an unmeasurable region within the plurality of measurement regions based on the measurement data output from said distance measuring sensor; a calculator for calculating a spacing on the object corresponding to the unmeasurable region detected by said detector; and a creator for creating distance data of the unmeasurable region based on the distance data of the measurable region among the plurality of distance measuring regions and the spacing calculated by said calculator.