Abstract
This paper first showed that an infrared distance measuring sensor could be used for vehicle detection effectively. In japan, reduction in costs oftraffic measurements conducted by manual observation is an important problem due to severe difficulties in public finance. The feasibility of new sensor application for a next generation traffic counter system is discussed. Three kinds of sensors, magnetic sensors, an ultrasonic sensor, an infrared distance measuring sensor, were investigated. The experimental data shows that the infrared distance measuring sensor could most accurately count vehicles in the front traffic lane with the simplest data processing.