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Cyanopsia is characterized by a persistent blue tint to the vision, which is the most noticeable symptom. This change in color perception may affect the entire visual field or be more prominent in specific areas.
Monochromacy (from Greek mono, meaning "one" and chromo, meaning "color") is the ability of organisms to perceive only light intensity without respect to spectral composition. Organisms with monochromacy lack color vision and can only see in shades of grey ranging from black to white. Organisms with monochromacy are called monochromats.
Leukocoria (also white pupillary reflex) is an abnormal white reflection from the retina of the eye. Leukocoria resembles eyeshine , but leukocoria can also occur in animals that lack eyeshine because their retina lacks a tapetum lucidum .
Achromatopsia, also known as rod monochromacy, is a medical syndrome that exhibits symptoms relating to five conditions, most notably monochromacy.Historically, the name referred to monochromacy in general, but now typically refers only to an autosomal recessive congenital color vision condition.
Dichromacy in humans is a form of color blindness (color vision deficiency). Normal human color vision is trichromatic, so dichromacy is achieved by losing functionality of one of the three cone cells. The classification of human dichromacy depends on which cone is missing:
For a pixel pair (one white and one black pixel) this gives a pixel density of 128 pixels per degree (PPD). 6/6 vision is defined as the ability to resolve two points of light separated by a visual angle of one minute of arc, corresponding to 60 PPD, or about 290–350 pixels per inch for a display on a device held 250 to 300 mm from the eye. [24]
The dots are usually black/gray on a white background and gray/white on a black background; however, they can also be transparent, white flashing, or colored. Presence of at least 2 additional visual symptoms of the 4 following categories: i. Palinopsia. At least 1 of the following: afterimages or trailing of moving objects. ii.
An Ishihara test image as seen by subjects with normal color vision and by those with a variety of color deficiencies. A pseudoisochromatic plate (from Greek pseudo, meaning "false", iso, meaning "same" and chromo, meaning "color"), often abbreviated as PIP, is a style of standard exemplified by the Ishihara test, generally used for screening of color vision defects.