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Abbots Ripton Rail Accident

The Abbots Ripton rail disaster occurred on 21 January 1876 at Abbots Ripton (England), when a passenger train from Edinburgh to London was involved in a collision, during a blizzard, with a coal train. A passenger train travelling in the…

Absorption spectrum

A photoreceptor is defined by which wavelengths of light it absorbs, which is represented by its absorption spectrum. The absorption spectrum is typically simplified into its peak wavelength, i.e. the wavelength of light to which it is most sensitive.

Achromatomaly

https://youtu.be/kYZ00B5O_VQ Achromatomaly is a term that has been posited as a new form of colorblindness or associated with other forms of colorblindness like Incomplete Achromatopsia or Blue Cone Monochromacy. The term was coined by a programmer in 2008 who extrapolated…

Achromatopsia

Achromatopsia is a severe form of colorblindness where subjects experience no or very limited color vision. Causes are diverse, affecting any part of the Phototransduction Pathway from the Photoreceptors to the Visual Cortex. Achromatopsia can be complete, where color vision…

Acquired CVD

Acquired CVD is a type of colorblindness that is not congenital CVD, i.e. it is acquired during an individual's life. There can still be a genetic component to acquired CVD, as some genetic causes of tritanopia are progressive and will…

Adobe RGB

A color space developed by Adobe in 1998. It was designed to encompass most of the colors achievable on CMYK color printers, but by using RGB primary colors on a device such as a computer display. Adobe RGB encompasses roughly…

Adobe Wide Gamut RGB

An RGB color space developed by Adobe, that offers a large gamut by using pure spectral primary colors. It is able to store a wider range of color values than sRGB or Adobe RGB color spaces. As a comparison, the…

Aesthetic

A type of Color Task, where an individual must appreciate or invoke the beauty inherent in a color or arrangement of colors. This often requires building harmonious combinations of colors, such as when picking an outfit. Artistic expression in painting,…

Afterimage

An effect of Photobleaching Photoreceptors. As your retina stares at a color, it will disproportionately Photobleach the Cones that are most sensitive to that color. While the Cones are still Photobleached, exposing them to a white image - which would…

Amacrine Cell

A type of neuron located in the retina. It combines information from several Photoreceptors and can be an intermediate step in the Phototransduction Pathway between the Bipolar Cells and a Retinal Ganglion Cell. They are very similar to Horizontal Cells.

Anomaloscope

An anomaloscope is an instrument used to test for CVD and is considered the gold standard to which other tests are compared. The apparatus was invented by the German ophthalmologist and physiologist Willibald A. Nagel (1870–1911) who named it "Anomaloskop"…

Anomalous Trichromacy

Anomalous Trichromacy is the weakest for of CVD. It comes in three flavours: ProtanomalyDeuteranomalyTritanomaly The severity of anomalous trichromacy spans a spectrum from essentially normal color vision to essentially dichromatic color vision.

AO PseudoIsochromatic Plates

A colorblind test published by the American Optical Company starting in 1940. At the outset of WWII, it became difficult for the USA and the allies to procure the two most popular colorblind tests at the time, the Stilling Test…

Arrangement Test

A category of tests for screening or diagnosing CVD where an individual must arrange colored tiles in a gradient. Individuals with CVD will misorder several of the tiles, and the error score correlates to the Severity of their CVD. Common…