APPASAMY ASSOCIATES KMS 6, Руководство пользователя

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Two plus signs will be seen between the left-hand and central focusing circles in the
instrument. The axis of the cylinder can be found easily when the axis of these plus signs
just touch.
Turn the horizontal lines of the drum until the plus signs are barely separated.
If the horizontal lines of the plus sign appear to be continuous and unbroken, the
instrument is set at the position of the axis of the astigmatism.
If the horizontal lines axis appears discontinuous the keratometer is not at the cylinder axis.
Grasp the keratometer at the “axis rotation grip” and rotate the entire tube while looking in
to the eyepiece. Using a somewhat trial and error approach, a position is reached at which
the horizontal lines of the plus signs will appear continuous and unbroken.
A further check on the accurate location of the axis may be obtained by throwing the
instrument slightly out of focus. Then the plus sign of the central of using circle will be
doubled. If the axis is correct, the horizontal line in the plus sign of the left circle will be
exactly midway between the double horizontal lines of the other plus sign.
If it is not at the midpoint, a slight rotation of the instrument one way or the other will move
the line to the midpoint. The double plus should next be focused, became continuous. This
extra check on the corneal axis is particularly valuable in low astigmatic errors. When these
horizontal white fines of the plus, signs appear tip to tip and indicate the axis of
astigmatism.
18
Measuring the Horizontal principal meridian
After the axis has been established, turn the horizontal measuring drum and the left hand