Samenvatting
Three color-normal and two color-blind subjects gave photonic luminosity functions by the method of critical frequency. By this method, the subject adjusts the radiance of intermittent light to produce threshold flicker for a constant rate of intermittence at various wavelengths. A family of contours was measured for various intermittence rates and a luminous efficiency function was derived from each contour. Contours showed systematic changes as frequency of intermittence increased.