A method and apparatus for inspecting a composite structure. A resin inspection system comprises a housing having an open section, a movement system associated with the housing, a light source associated with the housing, an infrared measurement system associated with the interior of the housing, and a visible light sensor system. The movement system is configured to move the housing on a surface of a composite structure. The light source is configured to emit light. The infrared measurement system is configured to generate infrared measurement information from infrared light detected by the infrared measurement system through the open section. The visible light sensor system is configured to generate image information about the surface of the composite structure.