60
Measurements can usually be obtained. However, if the contact lens is not
properly fitted, correct values may not be obtained. Dirt or scratch on the
contact lens may hinder measurement.
•
Measuring an eye with an eyeglass
Measurement is possible if the lens is at a slight incline. If the lens is at a
large incline, the correct values will not be obtained. If light is reflected from
the lens surface into the measuring window, or if the glasses have a colored
lens with a low light transmission, the measurement may fail.
▼ Representative values
After measurement is performed several times on one eye, the representative
values provide a guide for selecting from the measured values.
On the printout of measurement results, representative values are marked
with an asterisk “*”. See the “6
-
3 Samples Printout”
.
The confidence level is shown for representative values. The smaller the
variation between measured values, the closer the confidence level is to 10.
If measured values vary widely, such as in refractive measurement and you
want to select one from among them, note the following tips:
● If only the SPH values vary widely:
The patient's eye may be accommodating. Measure the same eye once again.
● If the CYL and AX values vary widely:
When CYL indicates weak astigmatism (below 0.5D), AX tends to be
somewhat unstable.
Other possible causes include:
•
Eyelashes are hanging over the pupil.
•
The main unit was tilted while the measurement was performed.
•
The pupil diameter is smaller than 2.3 mm, which is the minimum
measurable pupil diameter.
•
The eye is partially opaque, or is irregularly astigmatic.
In the above cases, the confidence level is typically low.
If eyelashes or pupil size are the cause, correct the problem and retry the
measurement.
▼ Refractive confidence level
The refractive confidence level indicates the degree of variation between
measurement results. It is given only after a measurement is run three or more
times; it appears at the right end of measurement results on printout. See
the”6
-
3Samples Printout”
.
•
8 or higher: Low variation.
•
7 or lower: High variation. Care is needed in interpreting the
measurement results.
▼ Auto power off
When no key is pressed for three minutes or more while no measurement is
being performed, the main unit automatically switches off.
To resume measurement, turn the power back on by pressing key.
