What would be the spherical equivalent of a (-2.00 + 2.00 x 90) lens?

Name: What would be the spherical equivalent of a (-2.00 + 2.00 x 90) lens?
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Quizplus · Accepted Answer

The spherical equivalent of a (-2.00 + 2.00 x 90) lens would be -1.00. The spherical equivalent is computed by algebraically adding half the cylinder power to the sphere power of a spherocylinder. It represents the average of the two powers that make up the spherocylinder. In this case: (-2.00) + (+2.00-(+1.00)) = (-1.00).

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