Images Dated 20th March 2003

View of a Snellen eye test chart

Snellen eye test chart. View of a Snellen eye test chart used for measuring visual acuity. A patient stands a set distance (usually six metres) from the chart, and covers one eye before reading as far down the chart as they can. The letters decrease in size lower down the chart. If they are unable to read a sufficient amount of the chart, lenses of different strengths are used until their vision is sharp enough to allow recognition of the smallest letters. In conjunction with other visual tests, this test allows the diagnosis of eye disorders such as long- and shortsightedness (hypermetropia and myopia). These disorders can be corrected with spectacles or contact lenses

© TEK IMAGE/SCIENCE PHOTO LIBRARY

Black-backed Australian Magpie - Male

DH-2927
Black-backed Australian Magpie - Male
Wilpena Pound, Flinders Ranges, Sth. Aust., Australia.
Gymnorhina tibicen
Don Hadden
Please note that prints are for personal display purposes only and may not be reproduced in any way

© Don Hadden/ardea.com

Australasia, Australasian, Australia, Australian, Bird, Magpie, Magpies, Male, Oceania, Single, Wild Life