Doublet
(Science: microscopy) two simple lens elements cemented together, for the purpose of giving spherical and chromatic corrections. An achromatic doublet may be composed of a positive crown-glass lens and a negative flint-glass lens. The errors of one element are made to compensate those of the other element.
Doublet (Science: microscopy) two simple lens elements cemented together, for the purpose of giving spherical and chromatic corrections. An achromatic doublet may be composed of a positive crown-glass lens and a negative flint-glass lens. The errors of one element are made to compensate those of the other element...
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