The OSIRIS-REx Camera Suite (OCAMS) will acquire images essential to collecting a sample from the surface of Bennu. During proximity operations, these images will document the presence of satellites and plumes, record spin state, enable an accurate model of the asteroid's shape, and identify any surface hazards. They will confirm the presence of sampleable regolith on the surface, observe the sampling event itself, and image the sample head in order to verify its readiness to be stowed. They will document Bennu's history as an example of early solar system material, as a microgravity body with a planetesimal size- scale, and as a carbonaceous object. OCAMS is fitted with three cameras. The MapCam will record color images of Bennu as a point source on approach to the asteroid in order to connect Bennu's ground-based point-source observational record to later higher-resolution surface spectral imaging. The SamCam will document the sample site before, during, and after it is disturbed by the sample mechanism. The PolyCam, using its focus mechanism, will observe the sample site at sub-centimeter resolutions, revealing surface texture and morphology. While their imaging requirements divide naturally between the three cameras, they preserve a strong degree of functional overlap. OCAMS and the other spacecraft instruments will allow the OSIRIS-REx mission to collect a sample from a microgravity body on the same visit during which it was first optically acquired from long range, a useful capability as humanity reaches out to explore near-Earth, Main-Belt and Jupiter Trojan asteroids.

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Aluminum mirrors and telescopes can be built to perform well if the material is processed correctly and can be relatively low cost and short schedule. However, the difficulty of making high quality aluminum telescopes increases as the size increases, starting with uniform heat treatment through the thickness of large mirror substrates. A risk reduction effort was started to build and test a ½ meter diameter super polished aluminum mirror. Material selection, the heat treatment process and stabilization are the first critical steps to building a successful mirror. In this study, large aluminum blanks of both conventional AA-6061 per AMS-A-22771 and RSA AA-6061 were built, heat treated and stress relieved. Both blanks were destructively tested with a cut through the thickness. Hardness measurements and tensile tests were completed. We present our results in this paper and make suggestions for modification of procedures and future work.

I present a Monte Carlo model for predicting the performance of integrating spheres as a function of incident flux direction. The model was developed specifically to aid in the design of integrating spheres used as cosine collectors but is of general applicability. I discuss a method of generating uncorrelated random numbers. The probability density functions associated with uniform irradiance over a circular entrance port and Lambertian reflectors or emitters are presented. A comparison of the model with analytic equations predicting performance for an unbaffled integrating sphere is included. The average of the data generated by the model agrees with the analytic solution for sphere throughput to better than 0.25% (ς = 8.3%).

In the ITER Core Plasma Thomson Scattering, the scattered light collection optics system is installed both inside and outside the diagnostic port under vacuum. The length of the optical path (∼6 m) and the need to shield the neutron and γ radiation increased the complexity of the system with the inclusion of multiple dog-legs, forcing the use of many elements with optical power. Multiple rounds of design have been required in order to satisfy iteratively the system requirements in terms of resolution, aberration, and shielding. The adoption of quasi-free-form reflective surfaces for several mirrors eventually allowed the correct compromise between all conflicting requirements.

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