23
11625-101-Rev. L
Instructions for Use
(continued)
Taking Measurements
(continued)
Operation of the Sphere Lens Dials
(continued)
6. The Strong Sphere Control introduces sphere power in 3.00D steps and can often be used as a
time saver.
Examples:
•
To obtain a power of +2.75D (starting from zero), the practitioner could add plus power in
quarter diopter steps by rotating the Weak Sphere Dial downward until +2.75D shows on the
sphere power scale.
• A quicker way: rotate the Strong Sphere Control nasally one index position to introduce a
value of +3.00. Rotate Weak Sphere Dial one index upward to reduce power to +2.75D.
•
To obtain a power of +7.00D (starting from zero) the quickest way: rotate Strong Sphere
Control nasally two index positions to introduce a value of +6.00D. Rotate Weak Sphere Dial
four index positions downward to increase power to +7.00D.
• To obtain a power of -3.50D (starting from zero) the quickest way: rotate Strong Sphere Con-
trol temporally one index to introduce a value of -3.00D. Rotate Weak Sphere Dial two index
positions upward to increase power to -3.50D.
