Adaptica 2WIN-S, Руководство оператора

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6.3 Measurement tips
•
For sphere and cylinder, measurement precision is
±
0.25 D or
±
0.50 D depending on the range.
The cylinder axis is calculated between 1° and 180° (step 1°) with precision of
±
5°. For high refractive
errors (above +7 D and below -7 D), the 2WIN displays “ high M ” (myopia) or “ high H ” (hyperopia) in
the upper part of the display. For higher refractive errors (above +15 D and below -15 D), the 2WIN
still displays
“ high M ” or “ high H ”: in this case, the 2WIN will not display a numerical result, but it will
write “ N.A. ” (Not Accessible measurement). For big refractive errors, in the case 2WIN succeeds to
estimate the spherical power only, this estimation will appear in the upper part of the display. This
maximum spherical estimation is between
±
15 D. Refer to Section 18.1 for further information.
•
Make sure the cylinder notation (minus or plus) is set to your preference.
•
Make sure the Reliability Index of the measurement is higher than 6 (max. is 9). In case it ’ s lower
than 6 a message with a hint will be displayed, for the repetition of the measurement.
•
Remember that non-cycloplegic refraction can vary depending on several conditions pertaining to
the binocular visual function; in some specific patients, including accommodating children, the 2WIN-
S measurements may vary.
7 Description of the device
7.1 2WIN and 2WIN-S
2WIN-S comprises the 2WIN and the accessory tube KALEIDOS.
A number of additional features of the 2WIN-S could be handled only approaching the 2WIN device.
Please, refer to the
2WIN Operator Manual for these options. This manual could be found in the
MicroSD inside 2WIN as well as downloaded at our website : adaptica.com > Products > 2WIN >
Manuals Download .
7.2 2WIN-S
The measuring principle of the 2WIN-S is based on infrared photorefraction. In this technique, infrared light
is projected through the pupils of the patient onto the retina. Depending on the refractive error, the reflected
light forms a specific crescent-shaped brightness pattern within the pupil. The spherical refraction is
calculated based on this crescent pattern. Cylinder and axis measurements are based on the same kind of
calculation, repeated on four meridians.
The 2WIN-S performs the measurement 1 meter (3 feet 3 inches) away from the patient ’s eyes , with
continuous tracking of the corneal reflex, for the analysis of the binocular alignment. The device works as a
portable darkroom and allows a contact-less measurement between the patient and the operator.