OSA's Digital Library

Journal of the Optical Society of America

Journal of the Optical Society of America

  • Vol. 54, Iss. 4 — Apr. 1, 1964
  • pp: 547–550

Area-Intensity Relations within the Fovea for Flickering White and Part-Spectrum Targets

P. J. FOLEY and J. KAZDAN  »View Author Affiliations

JOSA, Vol. 54, Issue 4, pp. 547-550 (1964)

View Full Text Article

Acrobat PDF (439 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Three experiments were performed (a) to derive indices of spatial summation for flickering white and three part-spectrum targets, on the assumption, verified in a previous experiment, that the index was the ratio of the slopes of the functions for CFF/log area and CFF/log luminance and (b) to investigate the effect of target/surround contrast on these functions.

It was found that, for part-spectrum targets at least, spectral composition is not a determinant of CFF and luminance is the effective variable. Further, the slope of the CFF/log luminance function increases with target area, depending upon the contrast between target and surround. It is suggested that these effects can be accounted for by postulating a family of sigmoid curves, representing the slope of the CFF/log luminance function as a function of log target size, with contrast as the parameter. These curves would have common upper and lower asymptotes, the points of inflection depending on the contrast.

P. J. FOLEY and J. KAZDAN, "Area-Intensity Relations within the Fovea for Flickering White and Part-Spectrum Targets," J. Opt. Soc. Am. 54, 547-550 (1964)

Sort:  Author  |  Journal  |  Reset


  1. R. A. Weale, Natl. Phys. Lab. Grt. Brit. Proc. Symp. 8, 447–459 (1957).
  2. P. J. Foley, J. Opt. Soc. Am. 51, 737–740 (1961).
  3. S. Hecht and S. Shlaer, J. Gen. Physiol. 19, 965–979 (1936).
  4. C. Landis, Physiol. Rev. 34, 259–286 (1954).
  5. A. Giorgi, J. Opt. Soc. Am. 53, 480–486 (1963).
  6. P. J. Foley, J. Opt. Soc. Am. 53, 975–977 (1963).
  7. If N>Nc, the observer cannot detect that the real luminance L, is varying over time; the impression he receives is that of a perfectly constant luminance Lm, the value of which is given by Talbot's law, i.e., [Equation].
  8. The lowest data points have the same contrast as the points immediately above. It is assumed that the differences are due to noise, and therefore the best fit for the theoretical line would be between them.

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