A low-power, LED-based, high-brightness anomaloscope
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Published on: September 27, 2019
Russell L Woods1, Ahmed L Rashed, Juan M Benavides
1The Schepens Eye Research Institute and Harvard Medical School, Boston, MA, USA. rwoods@vision.eri.harvard.edu
Abstract:
Color matches made with a Nagel anomaloscope are used in the differentiation of color vision deficiencies. When these color matches are made over a wide range of retinal illuminances, the changes in the color match provide information about the regeneration kinetics and the absorption spectra of the middle- and long-wavelength cone photopigments. These steady-state color matches vary with a variety of conditions, and may have value in screening for eye disease. Recently, high-brightness LEDs have become available that allowed us to construct a LED-based, high-brightness anomaloscope. We used inexpensive, low-energy components to replicate an earlier instrument, getting a maximum retinal illuminance over 5.6 log Trolands.
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