Oil droplets are a feature of some photoreceptor cells, mainly in birds and reptiles. The ancestor of humans had oil droplets, but these were lost during the Nocturnal Bottleneck. Oil droplets are positioned in front of the opsins, so light…

A very rare syndrome first described in [1973], which expresses itself as a very mild form of Incomplete Achromatopsia, with sub-par (uncorrectable) visual acuity & mild photophobia, but no clear color vision defects (according to anomaloscope). The cause is considered…

The individual visual units of an arthropod's (e.g. insects) compound eye. For example, the Drosophila (fruit fly), which is heavily studied in the visual sciences, has about 700 Ommatidia per eye. Each Ommatidium comprises several (~9) photoreceptors and several nerve…

A type of medical doctor that specializes in the eye (an Eye Doctor), therefore focusing on the diagnosis and treatment of disorders of the eye. They generally have 8 years of post-secondary education plus 5 years of residency (practical training).…

One of the three channels that comprise Opponent Process Theory, a Color Model that exists on the neurons of the optic nerve. The channels are: Luminance/Brightness (Channel A)Red-Green (Channel C1)Yellow-Blue (Channel C2-C3) The Opponent Channels are those in the box…

A theory for color vision first proposed by Ewald Hering in 1892, who disagreed with the prevailing theory at that: Trichromatic Theory ( Young-Helmholtz Theory ). Trichromatic theory suggests that color vision is based on three primary colors: red, green,…

A protein that (along with the Chromophore) makes up a Photoreceptor. The proteins are encoded in the Genome of an individual. They have two functions: They change the Peak Sensitivity of the Chromophore. Different peaks are required for Color Vision.They…

A Lantern made to replace the defunct Farnsworth Lantern. The Optec-900 is seen as a direct replacement and is slightly more restrictive that the original Farnsworth. While 24% of subjects with CVD pass the Farnsworth Lantern, only 19% pass the…

A profession that specializes in dispensing (fitting, recommending) glasses. They are not "Eye Doctors" and generally have a 2-year degree. They are not trained in CVD, but may be specifically trained in trialing Color Correction Lenses. A minority of Opticians…

A profession that specializes in prescribing corrective lenses and diagnosis of common eye diseases, defects or abnormalities. This is one type of Eye Doctor, but is not a medical doctor. They generally have 8 years of post-secondary education. A course…

When converting a full spectral image into a single excitation value, either with Opsin excitation or black & white photography, the Absorption Spectrum of the photoreceptive material is very important. In the early days of photography, it was difficult to…

Orthologs are genes in different species that both descended from the same gene in a common ancestor. The SWS gene in primates and the SWS1 gene in birds are orthologs. They both descend from the SWS1 gene that was present…