16
b. The optician makes inspection standing by the side of the testee,
and the latter is preferably situated against the light. Place the
instrument in the horizontal level (see Fig.9a), and target the guide
mark at the top of cornea of the testee.
c. After targeting is
fi
nished. Optician slides left/right pupi1
Measuring key to coincide the Benchmark spring with the top of the
lens (Fig.9b). The distance from the top of the cornea to the mounted
lens can be obtained by deducting the thickness of the lens from the
value digitally displayed at that time.
Fig. 9a Fig. 9b
5.6 LED and automatic power-off settings
a. Put F3 left pupil measuring keys to the left end and F10 right key
to the left end and keep them there, then press F4 (Function
Transition Key) continuously 5 times till the screen shows image of
“------”. After this, move F10 right measuring key to the right end
and press Function Transition Key again, then we get in the LED
brightness and automatic power-off setting mode.