Abstract

In the previous papers (see references 1–3) it was proved that the statistical nature of light and certain properties of the human apparatus for vision determine the threshold values for various times of observation and visual angles (expressed among others by the laws of Ricco, Talbot, and Piper) and the visual acuity. The behavior of these visual functions agreed with the two-quanta case: light is perceived when two quanta are effectively absorbed in the visual purple within an area corresponding to a visual angle of D (~10′) and within a time τ (~0.02 sec.). As the chance is negligible that the two quanta are absorbed in one rod, it proved that a rod reacts on the absorption of 1 quantum. The two stimuli will cooperate in the nerve system and give rise to light perception.

From experiments described in the present paper we conclude that after the absorption of a couple of quanta, all quanta absorbed within an area O corresponding with a visual angle o and a time T referred to this first couple of quanta, cause a stimulus which contributes to the brightness impression and the total number of stimuli within an area O and a time T determines the brightness impression.

The experiments mentioned consist in the determination of the dependence of the average numbers of quanta of a flash necessary for a fixed brightness impression on the visual angle and the time of observation.

The area O and the time T are the cause for the existence of the laws of Talbot and Ricco for the brightness impression. As soon as the time of the flash t or the visual angle d exceeds the value T or O, the average number of quanta necessary for a constant brightness impression is proportional to d² c.q. t. The area O has the nature of a recipient unit and T of an averaging time.

© 1948 Optical Society of America

The Two-Quanta Explanation of the Dependence of the Threshold Values and Visual Acuity on the Visual Angle and the Time of Observation

M. A. Bouman and H. A. van der Velden
J. Opt. Soc. Am. 37(11) 908-919 (1947)

The Two-Quanta Hypothesis as a General Explanation for the Behavior of Threshold Values and Visual Acuity for the Several Receptors of the Human Eye

M. A. Bouman and H. A. van der Velden
J. Opt. Soc. Am. 38(7) 570-581 (1948)

Absolute Threshold Conditions for Visual Perception

M. A. Bouman
J. Opt. Soc. Am. 45(1) 36-43 (1955)

On the Integrate Capacity in Time and Space of the Human Peripheral Retina

M. A. Bouman and G. van den Brink
J. Opt. Soc. Am. 42(9) 617-620 (1952)

Size, Shape, and Contrast in Detection of Targets by Daylight Vision. II. Frequency of Seeing and the Quantum Theory of Cone Vision*

Edward S. Lamar, Selig Hecht, Charles D. Hendley, and Simon Shlaer
J. Opt. Soc. Am. 38(9) 741-755 (1948)