Refractive State, Accommodation, and Resolving Power of the Fish Eye

  • H. O. Schwassmann
Part of the NATO Advanced Study Institutes Series book series (NSSA, volume 1)


The refractive state of the eye is a measure of the difference between the focal distance of the dioptric elements and the distance at which the receptors are located. If parallel rays of light incident on the pupil, as they would be when they come from an object at long distance, are brought to a point focus in the plane of the light-sensitive outer segments of the photoreceptors, the eye is said to be emmetropic. If the rays from the distant object focus in front of the receptor layer, the eye is considered myopic, or near-sighted, and only a blur would exist at the photoreceptor level. This blurred image can be brought into sharp focus by reducing the object-to-eye distance, since the image plane of a near object lies at a longer distance from the lens than that of an object farther away.


Receptive Field Refractive Error Refractive State Retractor Muscle Photic Stimulation 
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  1. Baylor, E.R. (1967). Vision of Bermuda reef fishes. Nature (London) 214: 306–307.CrossRefGoogle Scholar
  2. Baylor, E.R. and Shaw, E. (1962). Refractive error and vision in fishes. Science 136: 157–158.PubMedCrossRefGoogle Scholar
  3. Beer, T. (1894). Die Accommodation des Fischauges. Pflügers Archiv. Gesamte Physiol. 58: 523–649.CrossRefGoogle Scholar
  4. Glickstein, M. and Millodot, M. (1970). Retinoscopy and eye size. Science 168: 605–606.PubMedCrossRefGoogle Scholar
  5. Meyer, D.L. and Schwassmann H.O. (1970). Electrophysiological method for determination of refractive state in fish eyes. Vision Res. 10: 1301–1303.PubMedCrossRefGoogle Scholar
  6. Munk, O. (1973). Early notions of dynamic accommodatory devices in teleosts. Vidensk. Medd. Dan Naturhist. Foren. KBH 136: 7–28.Google Scholar
  7. Rochon-Duvigneaud, A. (1943). Les yeux et la vision des vertébrés. Masson, Paris.Google Scholar
  8. Schwassmann, H.O. and Meyer, D.L. (1971). Refractive state and accommodation in the eye of three species of Paralabrax (Serranidae, Pisces). Vidensk. Medd. Dan Naturhist Foren KBH 134: 103–108.Google Scholar
  9. Sivak, J.G. (1974). The refractive error of the fish eye. Vision Res. 14: 209–213.PubMedCrossRefGoogle Scholar
  10. Tamura, T. (1957). A study of visual perception in fish, especially on resolving power and accommodation. Bull. Jap. Soc. Sci. Fish. 22: 536–557.CrossRefGoogle Scholar
  11. Verrier, M.L. (1948). La vision des vertébrés et les théories de la vision. Ann. Biol. 24: 209–239.Google Scholar
  12. Walls, G.L. (1942). The vertebrate eye and its adaptive radiation. Cranbrook Inst. Science, Bloomfield Hills, Mich., Reprint Hafner, New York 1967, 785 pp.Google Scholar
  13. Wilkinson, F. (1972). A behavioural measure of grating acuity in the goldfish. Thesis, Dalhousie University, Halifax, N.S., Canada.Google Scholar

Copyright information

© Plenum Press, New York 1975

Authors and Affiliations

  • H. O. Schwassmann
    • 1
  1. 1.Department of ZoologyUniversity of FloridaGainesvilleUSA

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