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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

Information

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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