Optical MathQuestion 97 of 100
What is the combined horizontal prism when the right lens gives 2 prism diopters base out and the left lens gives 1 prism diopter base out?
a.1 prism diopter base out total
b.2 prism diopters base in
c.3 prism diopters base out total
d.0 prism diopters
Explanation
Horizontal prisms of the same base direction in the two eyes add together. 2 base out + 1 base out = 3 prism diopters base out total split across the two eyes.
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