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10.12
10.12
10.12
10.12
Jackson Cross Cylinder Test
Purpose: Subjective test, revise maximum circumference refractive power and axis for
Monocular, using Jackson Cross Cylinder
Chart: Dot-Group Chart
Auxiliary Lens: Cross Cylinder Lens (0.25 / 0.50)
Target: The Dot-Group Chart must be seen as same, although the Cross Cylinder is crossed.
Way of Test
1.
On Special Chart clause of touch screen, press Dot-Group Chart to move on to Cross
Cylinder Test Mode.
2. Press (R) or (L) to choose the field for test.
3. On the touch screen, press [CC 0.25] [CC 0.50] button to change it into Jackson
Cross Cylinder Mode.
4. While pressing number
⑴
and number
⑵
, ask the patient
which side letter is seen more clearly.
▶
If number 1 is seen clearly, turn the dial counterclo direction).
▶
If number 2 is seen clearly, turn the dial clockwise(- direction).
5. To estimate the distorted vision axis, press [A] or left/right button. To estimate
circumference power, press [C] or left/right button.
[Figure 10-12] Jackson Cross Cylinder Test (Distorted Vision Axis Test)
