. Physiological optics : being an essay contributed to the American encyclopedia of ophthalmology . 4322 M 50 M 40 M 40 F 31 F 25 F 25 8 654 M 32 M 32 Average 45 PHYSIOLOGICAL OPTICS W. Krause found as the index of the external layer , for theintermediate and for the nucleus Woinow gives , and 1
. Physiological optics : being an essay contributed to the American encyclopedia of ophthalmology . 4322 M 50 M 40 M 40 F 31 F 25 F 25 8 654 M 32 M 32 Average 45 PHYSIOLOGICAL OPTICS W. Krause found as the index of the external layer , for theintermediate and for the nucleus Woinow gives , and respectively. V. OCULAR CATOPTRICS AND THE MATHEMATICAL PRINCIPLES OP OPHTHALMOMETRYAND OPHTHALMOPHAKOMETRY AND THEIR APPLICATIONS 34. Ophthalmometry, or keratometry, is the measurement of cor-neal curvature and particularly, in practice, of the determination ofthe differences in the curves in order to determine the amount ofcorneal astigmatism. The cornea, having a clear reflecting surface, acts as a convex mirrorand the laws governing the conjugacy of foci of mirrors may heapplied Fig. 12.—Illustrative of the Laws of Reflection and Formation of Images in Convex Mirrors. 35. Let MN be the reflecting surface of a convex mirror. LetA1B1 be the object. In order to find the image position we proceedas in Fig. 12. CN represents the radius of curvature; the point Nis the pole. We proceed as follows:—(1) A ray of light, AtM, parallel to theprincipal axis, BXC, will strike the convex mirror at the point to the laws of reflection at plane surfaces, considering aninfinitesimal unit plane at M, the angles of incidence (i) and reflec-tion (r) are equal and the ray after reflection travels in the directionDM. This ray when projected backwards will cut the principal axisat a point F, half way between the pole N and the center C, knownas the principal focus. (2) A ray AJS, directed toward the center of curvature, will pro-ceed normally to the spherical surface an
Size: 2555px × 978px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectphysiologicaloptics
