Rethinking the Process of Vision

One hears again that “the gene for (or, “that is associated with”? or,”that causes”?) the condition of macular degeneration has been discovered”. This is yet another all-encompassing genetic explanation for a biological condition without any correlative physical explanation! [... More»]

I had thought (and I believe written) that a retina composed of an array of receptors of a single size would respond only to a single wavelength, i.e., have a monchromatic response. [... More»]

As opposed to the traditional view where a tacit assumption is that information about the vision process can be elicited from such types of measurements as microspectrophotometry of dead retinal sections, [... More»]

It is really obvious that the light interactive photosynthesizing organelles of plants and algae (and their granal and stromal ultra structures) represent a logical optimization by these biological organisms of this structural mechanism to interact with light over necessarily-extended, energy-absorbing areas. [... More»]

I recall a reference to the effect that the outer segments of the retina should be viewed as an “almost crystalline array“. This captures the idea of this model..it is the precise (and exquisite!) geometric spacing of the array of receptor outer segments (or “nanowires”) that is effecting light interaction. [... More»]

Single retinal receptors do not at all perform the function historically attributed to them of “detecting color”. Rather, light detection elements on the retina comprise pairs of receptors that function as dimensional “optical antennas” that are tuned to only three discrete wavelengths. [... More»]

From the New York Times of January 29, 2004 (Circuits, p.E-8) “A Harvard group has reported fabricating “optical nanowires” formed of glass light guides that are smaller in diameter than the wavelength of visible light. A quote from the report:”the nanowires become the path around which the light waves flow. The thinner the wire, the more energy goes into the evanescent field around it”. Light therefore travels as a wave outside of a fiber light guide when it’s diameter is smaller than light wavelength”.

This is the fundamental mechanism that I propose is involved in light interaction with retinal receptors, i.e., that light as a wave interacts outside of (or between) individual receptors. In this mechanism energy is transferred from the electromagnetic wave to the absorbing electron mass orthogonal to the direction of incident light via what is termed an “evanescent wave” …and this exactly explains the heretofore considered peculiar dichroic orientation of the rhodopsin complex in retinal receptors

Although I have considered for some time that evanescent wave phenomena provided the basis for energy coupling between the incident llight wave and the correct dichroic orientation of the rhodopsin chromophore contained within each receptor, I have not discussed this subject in this paper which has attempted to stress the beauty and simplicity of the geometric concept and was addressed primarily to the vision community.

See this link for a brief discussion of evanescent wave phenomenon as the coupling mechanism between incident light and the rhodopsin complex

I failed to add yesterday that to completely understand the vision of any specie one must additionally have morphological measurements of the structures of the eye, (distances, indices of refraction of each element etc.) in order to computer simulate the eye’s light refractive properties. [... More»]

I noted in my original paper that if the visual band of a specie of fish extended into the near-infrared the retinal receptors of that specie would be larger in diameter than those on the human retina. I cited a reference where the receptors of a specie of trout measured seven microns in diameter in seeming agreement with my prediction (the diameter of human cone receptors approximates one micron). [... More»]