Nidek Medical RT-5100, Руководство оператора

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TEST METHOD Astigmatism test
4.2 Astigmatism test
4.2.1 Astigmatism test with astigmatism clock dial
Chart: Astigmatism clock dial
Ideal appearance: The sharpness of all bars is equal.
[Procedure example]
1
Press or to occlude either measuring window.
2
Present the astigmatism clock dial chart.
Press . The RT-5100 goes into CYL mode.
When the cylinder value is not 0, change it to 0.
3
Fog the vision until the VA becomes about 20/200.
1) Press to go into SPH mode.
2) Turn the dial counterclockwise and add positive lenses.
4
Reduce the fogging until the VA becomes about 20/40.
*26
Turn the dial clockwise.
5
Ask the patient, “Does any bar appear especially sharper than the others? Or, are they
about the same?”
All the bars appear equal.

No astigmatism. The test is completed.
One of the bars appears sharper.

Obtain the cylindrical axis in minus reading by multiply-
ing the smaller number (1 to 6) next to the bar by 30°.
For example: When Bar 2 appears sharper: 2 × 30°= 60°
6
Set the axis of the minus cylindrical lens to the value obtained is Step 5.
Press and turn the dial.
7
Add minus cylinder in 0.25 D increments so that all the bars appear equal.
Press and turn the dial clockwise.
When adding the cylindrical power changes the sharper bar:
When the sharpest bar moves in the counterclockwise direction

Decrease the axis value.
When the sharpest bar moves in the clockwise direction

Increase the axis value.
*26. The numbers (1 - 12) beside the bars correspond to the VA of 20/40.
161221687130 承認済
Uncontrolled copy when printed.