Patent ID: 7274436

Claim:
A distance measuring device for a vehicle, adapted to emit electromagnetic waves forward for a scan both in horizontal and vertical directions, to measure a distance to an object based on reflected waves therefrom and to judge whether said object is a vehicle or not; said distance measuring device comprising: vehicle recognizing means for judging whether or not a recognized vehicle is a front going vehicle that is traveling in the traffic lane in which own vehicle is traveling; range judging means for judging whether or not the distance to an object in front is within a specified preset range; and vehicle confirming means for confirming an object to be a vehicle at later scans if said object has been judged by said range judging means to be at a distance within said specified preset range and if a first condition and a second condition are satisfied; wherein said first condition is that said object is judged by said vehicle recognizing means to be a front going vehicle continuously over a time longer than a preset minimum time length, and wherein said second condition is that the difference between the distance to said object measured by a scan that is earlier than said later scans and is the highest or nearly the highest in the vertical direction and the measured distance to a front going vehicle corresponding to said object is within a predetermined range.