Near visual acuity test

Near visual acuity test is usually done at a distance within arm’s length. A distance of 40cm is usually taken to be standard and is assumed to be a distance where usually most people keep

their objects while reading. However, distance also varies as per individual needs, varying between a range of 33–50cm. Reading tests are primarily used to verify the prescribed reading

correction as a part of routine eye examination. The emphasis

while reading test is on reading performance and not on optics.

This implies that any reading sample, whether it is letter text

or word text or continuous text may be used for the purpose.

Convention is to use the continuous text in the form of small

paragraphs set in different sizes because in normal day to day

life most people read continuous text arranged in different

paragraphs, not just an isolated letter or word. Another important

aspect to understand is that the near acuity score should be

equal to the score of distance visual acuity provided that the test

chart luminance level are comparable and letter test charts used

are on same principle and the eye is accommodated for near or

optically corrected to provide good focus for retinal image.

However, there is exception, as patients with posterior

subcapsular cataract whose pupil constriction at near vision

tasks causes the pupil area to become more completely filled

with the cataract so that the visual acuity becomes degraded.

The size of the typeset used is specified in “Point” units

which is widely used in printing industry. One point is equal to