Popis: |
A needed capability for making optical scatter measurements led the Lockheed company to design, build, and use an initial scatter measurement system. Experience with this early system revealed a number of unanticipated shortcomings. A new and improved system, designated as the BOSM Facility, was designed and built to correct the shortcomings and to improve functional capabilities. This facility will be described in this paper. The facility consists of three principle modules. First, there is a collimated light source with a variety of beam control features based on a fixed beam propagation direction. Second, there is a sample holder with three gimbal motions and a variety of controls. It is configured to facilitate and to optimize BRDF/BTDF measurements. Third, there is a PMT based photometer, with special electronic processing, mounted on a boom structure that pivots about the vertical center of the test sample. The gimbal and boom angle combinations provide the required bi-directionality. A facility computer with specialized software automatically controls illumination spot size and intensity, gimbal and boom angles, photometer measurements, and processing of raw measurement data into BRDF/BTDF output data. The software organizes these results into descriptive, tabular, and graphical reports. Other features, believed novel, are included in the facility design. |