The principles and methods of geometrical optics : especially as applied to the theory of optical instruments / by James P. C. Southall.

  • Southall, James P. C. (James Powell Cocke), 1871-1962.
Date:
1913
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Licence: In copyright

Credit: The principles and methods of geometrical optics : especially as applied to the theory of optical instruments / by James P. C. Southall. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    J, J 150. The symbols /, J denote the so-called zero-invariants in the case of the refraction of paraxial rays at a spherical surface, with respect to the two pairs of conjugate axial points M, M' and M, M\ respectively (24, 25, 26 and 27); thus, J = n(i/r —i/u) = n'(i/r—i/u'); J=n(i/r— i/u) =n'{ijr— i/u'); (see 98, 103, 155). In the case of a centered system of spherical surfaces, Jb, Jk denote the zero-invariants for the &th surface, with respect to the pairs of conjugate axial points M'k_v M'k and M'k_v M'k, respectively. In Chap. XIII, Jk, Jk denote the zero-invariants, with respect to the kth. surface, for paraxial rays of light of colours X, X, respectively, emanating originally from the same axial object-point. K, k 151. K = n-sin a = n'-s'm a! denotes the magnitude of the optical invariant in the refraction of a ray of light (122 and 155). 152. The symbol k, which occurs usually as a subscript, denotes the series-number of any one of a system of refracting (or reflecting) surfaces; or of any integral part or component of a compound optical system. In certain prism-formulae, the subscripts i and r occur also in this same sense. L 153. In Chap. XIV, L, V are used to denote the quantities of light-energy emitted in unit-time by a certain portion of a luminous object and the corresponding portion of the image, respectively. m 154. The total number of refracting surfaces of a system is denoted by m; also, the total number of components (prisms, lenses or lens- combinations) of a compound optical system. n, n 155. The absolute indices of refraction of the first and second medium are denoted by n, nf, respectively. When a ray traverses a series of media, the symbol n'h = n/c+l is used to denote the absolute index of refraction of the (k + i)th medium. Note that n'0 = nx denotes the absolute index of refraction of the first medium.