Abstract

The flash duration producing maximum brightness-enhancement changes as a power function of luminance, that is, the time locus of the Broca–Sulzer flash duration T_B, decreases as luminance L increases: T_B = k × L^β, where β is the duration exponent. The exponent of T_B was estimated for 1-deg white flash with five luminance levels covering the range 3.94–1.94 log cd/m² in steps of 0.5 log unit. The retinal loci tested were fovea, 10-, 20-, 30-, 40-, 50-, and 60-deg temporal eccentricities of the dark-adapted human right eye. The following method of brightness maximization was used: the observer adjusted the duration of constant luminance flashes to produce a maximally bright flash. Duration was adjusted by rotating a microprocessor-based potentiometer. The results showed that the duration of the brightest flash T_B decreased as L increased with the negative power exponent. Furthermore, the size of the negative exponent decreased as a function of increasing retinal eccentricity. Time-dependent brightness processing in the fovea and periphery is discussed in terms of the psychophysical brightness power function.

© 1982 Optical Society of America

Brightness function: Effect of area and duration

R. J. W. Mansfield
J. Opt. Soc. Am. 63(8) 913-920 (1973)

Spatial factors in the Broca–Sulzer phenomenon*

Lawrence E. Arend
J. Opt. Soc. Am. 63(7) 879-883 (1973)

Brightness exponent for the periphery in the Bloch region

Naoyuki Osaka
J. Opt. Soc. Am. 68(1) 140-142 (1978)

Category Judgments as Functions of Flash Luminance and Duration*

Mark F. Lewis
J. Opt. Soc. Am. 55(12) 1655-1660 (1965)

Difference Limen as a Function of Retinal Eccentricity and Background Brightness*

Patricia McBride Blough
J. Opt. Soc. Am. 48(10) 731-735 (1958)