Hall, Edwin Herbert, 1855-1938 · New York, H. Holt and company · leaf 149
Fig. 101. Lenses are classed as convex, or converging, and concave,or diverging. Convex lenses are all thicker in the middlethan at the margin, and cause parallel light-rays to con-verge, as in Fig. 102. Concave lenses are thinner in the … Fig. 102. Fig. 103. middle than at the margin, and cause parallel light-rays todiverge, as in Fig. 103. Some of the lenses used in the most accurate optical in-struments have convex or concave surfaces, which are notstrictly parts of spherical surfaces. Such lenses possesscertain advantages over…
Physics
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
