Active optics

Active optics is a technology used with reflecting telescopes developed in the 1980s,^[1] which actively shapes a telescope's mirrors to prevent deformation due to external influences such as wind, temperature, and mechanical stress. Without active optics, the construction of 8 metre class telescopes is not possible, nor would telescopes with segmented mirrors be feasible.

This method is used by, among others, the Nordic Optical Telescope,^[2] the New Technology Telescope, the Telescopio Nazionale Galileo and the Keck telescopes, as well as all of the largest telescopes built since the mid-1990s.

Active optics is not to be confused with adaptive optics, which operates at a shorter timescale and corrects atmospheric distortions.

^ Hardy, John W. (June 1977). "Active optics: A new technology for the control of light". IEEE Proceedings. Proceedings of the IEEE. 66: 110. Bibcode:1978IEEEP..66..651H. Archived from the original on 2015-12-22. Retrieved 2011-06-01.
^ Andersen, T.; Andersen, T.; Larsen, O. B.; Owner-Petersen, M.; Steenberg, K. (April 1992). Ulrich, Marie-Helene (ed.). Active Optics on the Nordic Optical Telescope. ESO Conference and Workshop Proceedings. Progress in Telescope and Instrumentation Technologies. pp. 311–314. Bibcode:1992ESOC...42..311A.

[1] Hardy, John W. (June 1977). "Active optics: A new technology for the control of light". IEEE Proceedings. Proceedings of the IEEE. 66: 110. Bibcode:1978IEEEP..66..651H. Archived from the original on 2015-12-22. Retrieved 2011-06-01.

[2] Andersen, T.; Andersen, T.; Larsen, O. B.; Owner-Petersen, M.; Steenberg, K. (April 1992). Ulrich, Marie-Helene (ed.). Active Optics on the Nordic Optical Telescope. ESO Conference and Workshop Proceedings. Progress in Telescope and Instrumentation Technologies. pp. 311–314. Bibcode:1992ESOC...42..311A.

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