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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Editor: Franco Gori
  • Vol. 31, Iss. 7 — Jul. 1, 2014
  • pp: 1577–1587

On calculating metamer sets for spectrally tunable LED illuminators

Graham Finlayson, Michal Mackiewicz, Anya Hurlbert, Bradley Pearce, and Stuart Crichton  »View Author Affiliations

JOSA A, Vol. 31, Issue 7, pp. 1577-1587 (2014)

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Solid state lighting is becoming a popular light source for color vision experiments. One of the advantages of light emitting diodes (LEDs) is the possibility to shape the target light spectrum according to the experimenter’s needs. In this paper, we present a method for creating metameric lights with an LED-based spectrally tunable illuminator. The equipment we use consists of six Gamma Scientific RS-5B lamps, each containing nine different LEDs and a 1 m integrating sphere. We provide a method for describing the (almost) entire set of illuminant metamers. It will be shown that the main difficulty in describing this set arises as the result of the intensity dependent peak-wavelength shift, which is manifested by the majority of the LEDs used by the illuminators of this type. We define the normalized metamer set describing all illuminator spectra that colorimetrically match a given chromaticity. Finally, we describe a method for choosing the smoothest or least smooth metamer from the entire set.

© 2014 Optical Society of America

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(330.1715) Vision, color, and visual optics : Color, rendering and metamerism

ToC Category:
Vision, Color, and Visual Optics

Original Manuscript: December 13, 2013
Revised Manuscript: April 3, 2014
Manuscript Accepted: May 20, 2014
Published: June 24, 2014

Graham Finlayson, Michal Mackiewicz, Anya Hurlbert, Bradley Pearce, and Stuart Crichton, "On calculating metamer sets for spectrally tunable LED illuminators," J. Opt. Soc. Am. A 31, 1577-1587 (2014)

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