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Journal of the Optical Society of America

Journal of the Optical Society of America

  • Vol. 42, Iss. 8 — Aug. 1, 1952
  • pp: 529–534

The Photopic Luminosity Curve for a Group of Fifteen Egyptian Trichromats

I. G. H. ISHAK  »View Author Affiliations

JOSA, Vol. 42, Issue 8, pp. 529-534 (1952)

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The photopic luminosity function for fifteen Egyptian observers with normal color vision has been measured every 100A between 0.41µ and 0.46µ by the direct comparison method and between 0.46µ and 0.70µ by the flicker technique on Wright’s colorimeter. Two humps at about 0.45µ and 0.48µ have been noticed but are more pronounced than those found by previous investigators. An analysis of the present data and the more important previous investigations has been made. It was found that the discrepancies among the different results could be partly accounted for by differences in the observational conditions and differences in the densities of the yellow macular pigmentation among the observers. The results also confirm Jacobsen’s finding that the C.I.E. luminosity function is low at the blue end of the spectrum.

I. G. H. ISHAK, "The Photopic Luminosity Curve for a Group of Fifteen Egyptian Trichromats," J. Opt. Soc. Am. 42, 529-534 (1952)

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