Abstract: A portable apparatus for uniformly illuminating a detector that includes an array of charge-coupled devices (CCDs) is provided for facilitating calibration of the respective gains of the CCDs. The illumination apparatus includes a housing, such as a cup-shaped housing, which defines an internal cavity and which opens through a first end. The illumination apparatus also includes a light source, such as a photoluminescent sheet, that is disposed within the internal cavity for uniformly illuminating the plurality of CCDs to thereby permit the CCDs to be calibrated. The illumination apparatus is also adapted to be mounted to the detector, such as by means of a mounting ring, in much the same fashion that a camera lens is attached to a camera. As such, the illumination apparatus can be readily mounted to a detector, such as a CCD camera, such that the array of CCDs can be calibrated in an efficient manner in the field, i.e., without requiring the detector to be transported to a laboratory for calibration.

Abstract: A system (50) for determining strain includes: a stimulating light source (54, 56); a device (64) for placing stress on an object (58); a number of local strain gauges (66) attached to the object (58); and an image capturing device (62, 64). A controller (52) is coupled to the stimulating light source (54, 56) and has a signal that turns on the stimulating light source (54, 56). The controller (52) receives a strain signal from each of the local strain gauges (66) located on the object (58). The controller (66) has an image signal that determines when the image capturing device (62, 64) captures an image.

Abstract: A method of determining pressure requires that a three dimensional surface of an object (14) be covered with a pressure sensitive coating. Next a raw first image (74) is acquired while the object (14) is not under test and a raw second image (74) is acquired while the object is under test. The raw first image (74) and the raw second image (74) are adjusted for a dark image (76) to form an adjusted first image and an adjusted second image. The adjusted first image and the adjusted second image are mapped (78) from a two dimensional representation onto a three dimensional model, to form a first model and a second model. A ratio model is formed (80) by taking the ratio of the intensity of the first model and the second model. Finally, a pressure is determined (84) for every surface that forms the three dimensional model.