Search results
Results From The WOW.Com Content Network
Snellen chart. Purpose. Snellen chart is used to estimate visual acuity (last three rows are 20/15, 20/13 and 20/10) A Snellen chart is an eye chart that can be used to measure visual acuity. Snellen charts are named after the Dutch ophthalmologist Herman Snellen who developed the chart in 1862 as a measurement tool for the acuity formula ...
Contact lenses. to correct refractive errors of the eye; a little invasive. Phoropter. used in refraction testing. Tonometers. used to determine the intraoccular pressure (IOP) - useful in glaucoma; video link for various types of tonometers. Speculum: to keep the eyes open during any operation. Universal eye speculum.
logMAR chart. An eye chart is a chart used to measure visual acuity comprising lines of optotypes in ranges of sizes. Optotypes are the letters or symbols shown on an eye chart. [ 1] Eye charts are often used by health care professionals, such as optometrists, physicians and nurses, to screen persons for vision impairment.
Eye examination for visual acuity. Visual acuity is a measure of the spatial resolution of the visual processing system. VA, as it is sometimes referred to by optical professionals, is tested by requiring the person whose vision is being tested to identify so-called optotypes – stylized letters, Landolt rings, pediatric symbols, symbols for the illiterate, standardized Cyrillic letters in ...
Contrast (vision) Six renditions of a rocky shore photo with incremental contrast levels, clockwise from bottom left. Contrast is the difference in luminance or color that makes an object (or its representation in an image or display) visible against a background of different luminance or color. The human visual system is more sensitive to ...
Sugar Ray asked DJ Lethal to work on their album as they were a fan of the House of Pain song "Jump Around". [8] DJ Homicide appears on a few of the album's tracks, and was credited as a guest musician, being excluded from a group shot of the band on the back of the album, which shows them riding a rollercoaster.
Photopic vision is the vision of the eye under well-lit conditions ( luminance levels from 10 to 10 8 cd/m 2 ). In humans and many other animals, photopic vision allows color perception, mediated by cone cells, and a significantly higher visual acuity and temporal resolution than available with scotopic vision .
Eccentricity effect. The eccentricity effect is a visual phenomenon that affects visual search. As retinal eccentricity increases (i.e. the light of the image enters the eye at a larger angle and approaches peripheral vision), the observer is slower and less accurate to detect an item they are searching for. [ 1]