A dictionary of photography for the amateur and professional photographer (1889)
Wall, E. J. (Edward John), 1860-1928 · New York : E. & H.T. Anthony · leaf 110
nses are here given : — d e f Fig. x.— a, double convex; b> plano-convex; c, concavo-convex or converging meniscus ; d, double concave ; e> plano-concare j f, divergent meniscus. The first three, a, b} ct which are thicker at the centre than at the margins, are convergent or positive ; and the… … Fig. 2. are united to form a biconvex lens, and the concentration of the rays of light by such prisms or lens. Fig. 3 is the representation of the prisms forming a double
Photography
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