US Patent 7783376 Photogrammetric contrasting light for hole recognition

A system for measuring a hole of a surface may include at least one light emitting member for emitting varied intensity flashes of light towards the hole of the surface. The system may further include a projector for projecting light beams onto the surface. The system may additionally include at least one camera for taking at least one picture of the hole of the surface each time the at least one light emitting member emits a flash of light towards the hole of the surface, and each time the projector projects light beams onto the surface. The system may also include a computer for determining measurements of the hole of the surface utilizing the at least one picture of the hole and Photogrammetry.