active optics

noun plural in form but usually singular in construction

astronomy

: an optical telescopic system that improves image resolution by compensating for distortions in the material or shape of a mirror

Another technological trick called active optics will nullify changes in the telescope's structure that result from the effects of gravity and temperature.

—Thomas Levenson, Discover, February 2006

compare adaptive optics

Word History

First Known Use

1968, in the meaning defined above

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