Give the following prescriptions, assuming your working distance is 2/3 metres.

a. RE: With the streak at 90⁰ a +2.25 sphere neutralized the reflex; with the streak at 180⁰ (leaving a +2.25D sphere in place) a -2.50 D cylinder neutralized the reflex? 

b. LE: With the streak at 45⁰ a +2.00 sphere neutralizes the reflex, with the streak at axis 135⁰ a -1.00 lens neutralizes the reflex?

 

Answer a
RE: +0.75/ -2.50 X 180.
The two things to remember are:
a. The streak parallel the axis and 
b. As the working distance is 2/3 metres, -1.50 needs to be added to the sphere.
 

Answer b
LE: +0.50 /-3.00 X 135.