<title>Image restoration for the Hubble Space Telescope</title>

Abstract

The Hubble Space Telescope image quality was degraded significantly as a result of the spherical aberration in the primary mirror. Repairs made during the the First Servicing Mission have restored HST's optical performance to the original design specifications. This paper examines not only how effective image restoration has been for the data from the first three and a half years of the mission, but also demonstrates the applicability of the same deconvolution algorithms to post-servicing mission images.A variety ofwell-known image restoration techniques, such as Wiener filters, Richardson-Lucy, Janssonvan Cittert, CLEAN, and maximum entropy, have been applied to liST imaging with reasonable success. However, all techniques have been hampered by incomplete knowledge of the point spread function and the space variance of the point spread function (PSF) in the Wide Field / Planetary Camera, HST's most frequently used imager. After the servicing mission, the COSTAR-corrected Faint Object Camera acquires a space-variant PSF. Restoration is further complicated by time variance of the PSF resulting from both long-term and short-term (orbital period) changes in focus, problems which are not likely to be ameliorated by the servicing mission. Thus, it wifi be important to continue the efforts in modeling the HST optical system and apply deconvolution methods in order to attain the best scientific results from the telescope.

Large optical space-based telescopes

“…После 25-летней работы космического телескопа Хаббл на орбите его дальнейшее обслуживание агентством NASA не планируется. На сегодняшний день телескоп Хаббл по-прежнему остается самым большим космическим телескопом, рабо-тающим в диапазоне излучения от УФ до ближнего ИК [22,23].…”