Entries for December, 2005

Again, The Proper Definitions of Scotopic and Photopic Vision

Saturday, December 17th, 2005

The correct definitions (if the terms must be used at all):

SCOTOPIC VISION: “Under low light level conditions the rod cells of the peripheral retina act together (as a “light meter”) to dilate the pupil of the eye and admit the maximum amount of light. Under these conditions there is still insufficient RGB light falling on the the retina to activate the “Land color mechanism”, i.e., insufficient light intensity incident on either side of the geometrically determined mid-band point at 7 1/2 degrees of retinal angle for the “color” ratio to be obtained. The colorless, generally outline, image that is perceived results from long wavelength radiation falling on the central all-cone fovea.”

PHOTOPIC VISION: “Under normal, i.e., daylight, levels of illumination, the RGB light intensities abstracted by the retina are sufficient to activate the “Land color mechanism” as defined above and the “color” image is perceived by the color centers of the brain. Peripheral rods, acting together and determined by the short wavelength end of the visible spectrum, constrict the pupil thus continuing control of the intensity of light entering the eye as necessary”

On the Historical Misunderstanding That “Classes of Cones” Exist on the Retinal Surface - Focusing Now on the Non-Existence of “Green Sensitive Cones”

Tuesday, December 13th, 2005

I will begin by referencing Osterberg’s 1935 diagram of the distribution of cone and rod receptors on the retinal surface. I do not believe that there is any disagreement as to the validity of these data as it is appears in almost every textbook on vision and the eye. This diagram appears as Figure 2 of my original paper where it, in essence, forms the basis for this entire concept and where it is shown that this specific distribution of receptors is in exact consonance with the diffractive properties of the lens and structure of the eye. [… More»]