OSA's Digital Library

Journal of the Optical Society of America

Journal of the Optical Society of America

  • Vol. 60, Iss. 3 — Mar. 1, 1970
  • pp: 406–415

Interrelations among Stiles π Mechanisms

MITSUO IKEDA, TOSEIO UETSUKI, and W. S. STILES  »View Author Affiliations

JOSA, Vol. 60, Issue 3, pp. 406-415 (1970)

View Full Text Article

Acrobat PDF (1185 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Threshold summation indices were determined in a study of interrelations among Stiles π mechanisms. Test wavelengths of 630, 520, 475, and 420 nm were presented upon a 555-nm adapting field. The 630–520-nm test-stimulus combination showed very small summation indices compared to the index derived on the assumption of independence of the π4 and π5 mechanisms. We suggest that 5 is not a single or unitary mechanism, but is comprised of two components, π5r and π5g, that may inhibit or cancel each other’s effects in producing the net response of mechanism π5. The hypothesis also explains fairly well the observed small index for the combination 630–475 nm at low field luminance. The mechanisms π1, π4, and the composite π5 seem to be independent, as shown by good agreement between the calculated and experimental indices at high field luminance for the combination 630–475 nm, and over the entire range of field luminance for the combination 520–475 nm. Complete summation is observed for the combination 475–420 nm at high field luminance, with which mechanism π1 should be almost exclusively involved.

MITSUO IKEDA, TOSEIO UETSUKI, and W. S. STILES, "Interrelations among Stiles π Mechanisms," J. Opt. Soc. Am. 60, 406-415 (1970)

Sort:  Author  |  Journal  |  Reset


  1. M. Ikeda, J. Opt. Soc. Am. 53, 1305 (1963).
  2. M. Ikeda, J. Opt. Soc. Am. 54, 89 (1964).
  3. R. M. Boynton, M. Ikeda, and W. S. Stiles, Vision Res. 4, 87 (1964).
  4. W. S. Stiles, Newton Lecture, J. Colour Group No. 11, 106 (1967).
  5. S. L. Guth, J. Opt. Soc. Am. 55, 718 (1965).
  6. S. L. Guth, J. V. Alexander, J. I. Chumbly, C. B. Gillman, and M. M. Patterson, Vision Res. 8, 913 (1968).
  7. M. Alpern and W. A. H. Rushton, J. Physiol. (London) 176, 473 (1965).
  8. R. M. Boynton and S. R. Das, Science 156, 1581 (1966).
  9. R. M. Boynton, S. R. Das, and J. Gardiner, J. Opt. Soc. Am. 56, 1775 (1966).
  10. W. S. Stiles, Proc. Natl. Acad. Sci. (U.S.) 45, 100 (1959).
  11. F. H. C. Marriott in The Eye, H. Davson, Ed. (J. & A. Churchill Ltd., London, 1962), Vol. 2, p. 261.
  12. G. Wyszecki and W. S. Stiles, Color Science (John Wiley & Sons, Inc., New York, 1967), p. 574.
  13. M. Ikeda and M. Urakubo, J. Opt. Soc. Am. 59, 217 (1969).
  14. The characteristics of π5′ are known only in an incomplete and tentative sense. The proposed spectral sensitivity is given on p. 574 of Ref. 12.
  15. G. Wald, Science 145, 1007 (1964).
  16. R. M. Boynton, J. Opt. Soc. Am. 53, 165 (1963).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited