User's Manual

Table Of Contents
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5.5 Binocular Functional Testing Method
5.5.1 Crisscross matrix test (presbyopia)
Test purpose: to test the spherical power.
Test sighting mark: crisscross matric sighting mark
Assistant lens: binocular ±0.50D fixed crisscross cylinder
1. Binocular distant vision test is finished, add distant vision degree in the testing window.
2. Add binocular ±0.50D fixed crisscross cylinder.
3. Lower down the short-distance vision rod and place the visual chart in necessary working
distance (generally 400mm).
4. Select the crisscross matrix sighting mark on the short-distance visual chart.
5. Ask the patient: the horizontal line or the vertical line, which is more distinct? Or the horizontal
line and the vertical line look the same?
If the horizontal line and the vertical line look the same: there is no need to carry out near vision test
and wear presbyopia glasses.
If the horizontal line is more distinct than the vertical line: increase two eyes by +0.25D additional
degree synchronically until the horizontal line looks as distinct as the vertical line.
6. Remove ±0.50D fixed crisscross cylinder.
7. Select short-distance visual chart to test the vision and slightly adjust the sphere to make the
patient see the sighting mark clearly to reach ideal vision value.