Mangin mirror


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Mangin mirror

[män‚zhan ‚mir·ər]
(optics)
A negative meniscus lens whose shallower surface is silvered to act as a spherical mirror while the other surface corrects for spherical aberration of the reflecting surface; used in searchlights and aircraft gunsights.
References in periodicals archive ?
Maksutov's notebooks reveal that in 1936, when he was contemplating Mangin mirrors (lenses with one silvered surface, primarily used in spotlights and lighthouse beacons), he had penciled in the margin a little sketch showing the reflective and refractive elements of a Mangin mirror separated to form a meniscus lens and a mirror.