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Blue field entoptic phenomenon has the appearance of tiny bright dots moving rapidly along squiggly lines in the visual field. It is much more noticeable when viewed against a field of pure blue light and is caused by white blood cells moving in the capillaries in front of the retina. White cells are larger than red blood cells and can be ...
A-type stars are among the more common naked eye stars, and are white or bluish-white. They have strong hydrogen lines, at a maximum by A0, and also lines of ionized metals (Fe II, Mg II, Si II) at a maximum at A5. The presence of Ca II lines is notably strengthening by this point.
The normal human observer's relative wavelength sensitivity will not change due to background illumination under scotopic vision. The wavelength sensitivity is determined by the rhodopsin photopigment. This is a red pigment seen at the back of the eye in animals that have a white background to their eye called Tapetum lucidum.
Many variations occur, but scintillating scotoma usually begins as a spot of flickering light near or in the center of the visual field, which prevents vision within the scotoma area. It typically affects both eyes, as it is not a problem specific to one eye. [5] [6] The affected area flickers but is not dark. It then gradually expands outward ...
At least 1 of the following: excessive floaters in both eyes, excessive blue field entoptic phenomenon, self-light of the eye , or spontaneous photopsia. iii. Photophobia. iv. Nyctalopia; impaired night vision. Symptoms are not consistent with typical migraine aura.
The observer described them as being similar to "luminous balls seen in fireworks, with initial tails fuzzy and heads like tiny stars". The other observer who was given one exposure lasting three seconds long, reported seeing 25 to 50 "bright discrete light, he described as stars, blue-white in color, coming towards him". [8]: 596
Nedoroscik has learned how to navigate life with cross-vision — even eye surgery at age 8 did not solve the issue. Throughout his childhood, he wore glasses that darken in sunlight.
An artist's representation of how some people may see phosphenes by retinal stimulation. A phosphene is the phenomenon of seeing light without light entering the eye. The word phosphene comes from the Greek words phos (light) and phainein (to show). Phosphenes that are induced by movement or sound may be associated with optic neuritis. [1] [2]