The use of automatic license plate recognition systems for vehicle traffic flow monitoring in congested areas, both metropolitan and state/interstate highway, is the most effective method of determining traffic flow patterns today. The infrared camera image capture systems are robust and the resulting data is fed to a central computer server that calculates travel time across monitored segments in real time. Results are posted within a network environment and can be made available to anyone interested via Internet access to the results. This paper reviews the infrared camera technology in use
today, discusses its application to travel time monitoring and reviews a case study documenting the results of a specific travel time study.