A system for visual inspection of coated substrates is disclosed. Painted substrates can be inspected for environmental and physical damage such as corrosion and cracks without removing the paint through the use of infrared imaging. The present invention provides the ability to view abnormalities or defects in the substrate at an increased depth of field. This is accomplished by taking multiple images of the substrate at different focal planes then using computer software to merge the images. The merged image is in focus across the different focal planes and may also be viewed in three-dimensions.
 The United States Government has certain rights to this invention pursuant to the funding and/or contracts awarded by the Strategic Environmental Research and Development Program (SERDP) in accordance with the Pollution Prevention Project WP-0407. SERDP is a congressionally mandated Department of Defense (DOD), Department of Energy (DOE) and Environmental Protection Agency (EPA) program that develops and promotes innovative, cost-effective technologies.