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Paper: A Technique for a Self-Luminous Flatfield Calibration Screen
Volume: 364, The Future of Photometric, Spectrophotometric, and Polarimetric Standardization
Page: 571
Authors: Brown, Y.J.; Stubbs, C.W.; Henry, E.T.; Bailes Brown, L.
Abstract: The use of flatfield illuminators shows great promise for calibrating telescopes to be used in the next generation of Ia supernova measurements. In order to meet the physical constraints of the PanSTARRS and LSST domes, we are developing a self-luminous flatfield calibration screen which can cover the entrance aperture of these telescopes while presenting a total thickness of only 13 cm. We expect to achieve illumination uniformity and passband flatness adequate for optical throughput calibration at the 1% level. The emitting element is a “side-emitting” optical fiber excited by a pulsed laser tunable over the bandpass of 400 to 1100 nm. The fiber is embedded in a sheet of acrylic the size of the telescope aperture. This radiating element is backed by a mirror. In front of the radiator is an acrylic lambertian diffusing screen, and in front of the diffuser is a baffle screen that occults much of the light that would have entered the telescope by way of scattering from telescope and dome structures. The baffle screen is a sheet of black acrylic drilled with a densely packed array of threaded holes.
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