A stenopaic slit showed above is used to test the eye of
a patient with astigmatism.
When the slit is held at position a, the patient requires a +3.00D sphere to see clearly and when the slit is held at position
b, the patient requires a +2.00D sphere to see clearly.
a. Draw the power cross for this patient.
b. What is the prescription needed to correct this patient's vision.
