22
11625-101-Rev. L
Instructions for Use
(continued)
Taking Measurements
(continued)
Operation of the Sphere Lens Dials
1. All sphere powers, plus and minus, can
be introduced into the lens aperture in
steps of 0.25D by rotation of a single lens
dial, (+0.12D sphere in the Auxiliary Lens
Knob can be used to refine the spherical
correction to 1/8th D steps.)
2. The operation is simple. Rotation of the
Weak Sphere Dial downward (i.e. clock-
wise for the left eye, counterclockwise for
the right eye.) introduces more plus power
or less minus. Refer to Figure TM-3.
3. Rotation of the Weak Sphere Dial upward
introduces more minus power or less
plus. Refer to Figure TM-3.
Note:
Plus powers are indicated by black numbers; minus powers, by red numbers.
4. An automatic pick-up system links the two
sphere power dials so that whenever a
change in power is required in the Strong
Sphere Dial, it is automatically moved by
the Weak Sphere Dial. Thus, one may
dial completely through the +16.75D to
-19.00D range in 0.25D steps by rotation
of only the Weak Sphere Dial.
5. However, high power may also be intro-
duced quickly and easily by means of the
Strong Sphere Control when desired.
Refer to Figure TM-4.
-continued-
Figure TM-3 Moving Weak Sphere Dial
Figure TM-4 Rotating Strong Sphere Control
(Surrounds Auxiliary Lens Scale)
