OPTIKON KERATRON ONDA, Инструкция по установке и эксплуатации

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Keratron
™
Onda Installation and operating manual
OPTIKON 2000
Cod. 161401EN 7-18
2015-03-27
Rev.C
On the screen in Figure 7-29, in addition to the live image, appear the following: the
indication of the OD/OS eye under examination (1), the position of the band of the
superluminescent diode (SLD) indicated by a yellow circle (2), the
wavefront
sensor ) image (3) , and the indication of the distance from the eye by means of the
EPCS (4), with the selection of the pair of Near or Far photoelectric cells (5).
Figure 7-30: Warning for the deletion
of the previous acquisitions
NOTE:
This choice is made at the beginning of each test (max. 8 acquisitions, all at the
same operating distance), otherwise all of the previously acquired images will be
deleted. (see figure Figure 7-30).
At the beginning of the test it is necessary to compensate for, as well as possible,
any refractive error (sphere-equivalent, that is
defocus ) of the eye under
examination or to initiate an automatic search of the refraction (Auto RX). In fact, a
high degree of
defocus results in a reduction in the measurable range, which
instead should be kept at a dimension that is large enough to contain the pupil.
The measured
defocus will be used also as starting value for searching the
accommodation (fogging) to the remote point of the eye or to a closer point (see
Sections Figure 7-32, and §7.8).
If the refraction is known, you can proceed by moving the cursor (7) near the
desired
defocus value (listed in the bottom left-hand corner) of between
approximately -11 and +6.5 D.
Otherwise, if button [Auto RX] (6) is yellow (it can be set as “default” in “Settings” or
pressed), the
defocus automatic search is enabled .
The search is initiated by centering the eye and pressing the joystick’s button at the
OK distance, like for a normal topography.
Figure 7-31: Aberrometry target