Essilor Instruments Vision-R 800, User Manual

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• On the console keyboard, by turning the central button anticlockwise * .
> Start the test again until you obtain equal clearness between the horizontal and vertical lines or a
greater clearness for the vertical ones.
- equality of darkness between the horizontal and vertical ones retain this sphere value.
In the event of preferred inversion between the horizontal and vertical lines between two sphere
steps, retain the last values:
• " vertical “ for a patient with myopia
• " horizontal “ for a patient with hypermetropia
Notes
• To avoid the disturbing effects of accommodation, it is possible to scramble the patient (with a convex
power) until you obtain the preference for the vertical lines and to then clear up it until you achieve a
balance between the horizontal and vertical lines.
• The test of the fixed cross cylinders supposes an exact correction of the astigmatism of the eye. The
result can be distorted if a direct astigmatism (cylinder axis further from 0°) or the opposite (cylinder
axis further from 90°) is over or under-corrected.
• At the end of the test, the horizontal and vertical lines are slightly fuzzy (because the patient looks
through a cylinder of 1.00 D). The important thing is that the blurring is identical on the horizontal
and vertical lines.
(*)
This information corresponds to the phoropter default settings:
• The variation step of the sphere is by default 025 R, but it can be adjusted in the settings.
>
U
SER MANUAL
> IV. P
ERFORMANCE OF SPECIFIC TESTS DURING A REFRACTION EXAMINATION
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Vision-R 800 - Essilor automatic phoropter > V1 - 12-2018