Inferential Physical Measurements Using Detectors And Detector Arrays
Fred Abbott, K. Burhardt, Frederick M. Waltz · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1980
Some uses of photodiode detector arrays for on-line inferential measurement of process parameters are described in this paper. Optical considerations involving these arrays are discussed. High resolution camera lenses are not necessarily best in these applications since different lens design considerations apply when discrete arrays are used. Serious linearity and repeatability problems that were encountered with some commercially available solid state camera systems are discussed. The requirement of modest system cost, coupled with the need for high speed on line analysis, place stringent restrictions on the type and amount of computer analysis that can be carried out. A set of recognition algorithms which have worked well in the initial applications are described. Some of the remaining problems, and possible approaches to them, are presented.