Lummer, O. (Otto), 1860-1925, Thompson, Silvanus P. (Silvanus Phillips), 1851-1916 · London, New York, Macmillan and Co., 1900 · leaf 96
APHIC OPTICS 80 CHAP. middle converging meniscus lens of lower refractive index cemented to two lenses of higher index, of which that facing the stop is bi-concave and the other bi-convex. In this wise there are brought into existence both a converging and a diverging cemented surface, as is… … Fig. 24. — Voigtliinder’s Collinear. Fig. 25. — Steinheil’s Orthostigmat. the inventor, is well corrected spherically for an aperture-ratio of about //7, and possesses also good anastigmatic flattening with a wide extent of field. These lenses are now manufactured in England under the Voigtländer…
Photographic optics
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