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An improved retinal densitometer: Design concepts and experimental applications

Published online by Cambridge University Press:  02 June 2009

Howard D. Baker ,
Ross Henderson  and
Lawrence P. O'Keefe
Howard D. Baker
Affiliation:
Psychobiology/Neuroscience Program, Florida State University, Tallahassee
Ross Henderson
Affiliation:
Psychobiology/Neuroscience Program, Florida State University, Tallahassee
Lawrence P. O'Keefe
Affiliation:
Psychobiology/Neuroscience Program, Florida State University, Tallahassee
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Abstract

A photon-counting retinal densitometer is described that has been designed optically and electronically for improved sensitivity and reliability. The device allows measurement of visual pigments through the undilated natural pupils of subjects at relatively low levels of measuring lights, and serves also as an adaptometer for direct comparisons between pigment bleaching or regeneration and light or dark adaptation. Instrumental control and data collection are by computer to permit rapid and simple data analysis and comparisons between subjects. The methods by which the sensitivity and reliability have been enhanced are described in detail, and some examples of experimental results are presented.

Keywords

Visual pigmentDark adaptationVisual sensitivityRetinal densitometryFundus reflectometry
Type
Technical Contribution
Information
Visual Neuroscience , Volume 3 , Issue 1 , July 1989 , pp. 71 - 80
Copyright
Copyright © Cambridge University Press 1989

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References

Baker, H.D. & Coile, D.C. (1987). Retinal densitometry with the natural pupil. Investigative Ophthalmology and Visual Science (Suppl.) 28, 219.Google Scholar
Baker, H.D., Henderson, R., & O&Keefe, L.P. (1985). A photon counting retinal densitometer, Journal of the Optical Society of America A 2, P23.Google Scholar
Caceci, M.S. & Cacheris, W.P. (1984). Fitting curves to data. BYTE 05, 340–362.Google Scholar
Coolen, A.C.C. & van Norren, D. (1988). Kinetics of human cone pigments explained with a Rushton-Henry model. Biological Cybernetics 58, 123–128.CrossRefGoogle ScholarPubMed
Henderson, R.P. & Baker, H.D. (1979). Improving the retinal densitometer. Proceedings of the 32nd Annual Conference on Engineering and Medical Biology 21, 210.Google Scholar
Hollins, M. & Alpern, M. (1973). Dark adaptation and visual pigment regeneration in human cones. Journal of General Physiology 64, 430–447.CrossRefGoogle Scholar
Hood, C. & Rushton, W.A.H. (1971). The Florida retinal densitometer. Journal of Physiology 217, 213–229.CrossRefGoogle ScholarPubMed
Jacobs, S.F. (1978). Non-imaging detectors. In Handbook of Optics, ed. Driscoll, W.G. & Vaughan, W., pp. 4–1–4–69. New York: McGraw-Hill Book Co.Google Scholar
Kilbride, D.E., Hutman, L.P., Fishman, M. & Read, J.S. (1986). Foveal cone pigment density difference in the aging human eye. Vision Research 26, 321–325.CrossRefGoogle ScholarPubMed
King-Smith, P.E. (1973). The optical density of erythrolabe determined by a new method. Journal of Physiology (London) 230, 551–560.CrossRefGoogle ScholarPubMed
Ripps, H. (1986). Uses and abuses of fundus reflectometry. Paper presented at Workshop for Fundus Reflectometry and its Clinical Applications. Utrecht, Netherlands.Google Scholar
Ripps, H., Mehaffey, L. & Siegel, I.M. (1981). Rhodopsin kinetics in the cat retina. Journal of General Physiology 77, 317–334.CrossRefGoogle ScholarPubMed
Rodieck, R.W. (1973). The Vertebrate Retina. San Francisco, California: W.H. Freeman and Co., p. 56.Google Scholar
Rushton, W.A.H. & Henry, G.H. (1968). Bleaching and regeneration of cone pigments in man. Vision Research 8, 617–631.CrossRefGoogle ScholarPubMed
Rushton, W.A.H. & Powell, D.S. (1972). The rhodopsin content and the visual threshold of human rods. Vision Research 12, 1073–1081.CrossRefGoogle ScholarPubMed
Smith, V.C., Pokorny, J. & van Norren, D. (1983). Densitometric measurement of human cone photopigment kinetics. Vision Research 23, 517–524.CrossRefGoogle ScholarPubMed
van Norren, D., & van der Kraats, J. (1981). A continuously recording retinal densitometer. Vision Research 21, 897–905.CrossRefGoogle ScholarPubMed
van Norren, D. & Tiemeijer, L.F. (1986). Spectral reflectance of the Human Eye. Vision Research 26, 313–320.CrossRefGoogle ScholarPubMed
Weale, R.A. (1965). Vision and fundus reflectometry. Documenta Ophthalmologica 19, 252–286.CrossRefGoogle Scholar