What is the power of the intermediate addition for a trifocal lens given the following readings? A = -1.25 -1.00 X 135 B = -1.25 -1.00 X 045 C = +1.25 -1.00 X 045 D = pl -1.00 X 045

Given the following target positions, split the prism between the two lenses.

Determine the prescription of the following spherocylindrical lens, given the following lensmeter readings: Reading A = -6.50 D Reading B = 1150 Reading C = -4.25 D.

What is the power of the reading addition for a trifocal lens given the following readings? A = -1.25 -1.00 X 135 B = -1.25 -1.00 X 045 C = +1.25 -1.00 X 045 D = pl -1.00 X 045

What is the power of the intermediate addition for a trifocal lens given the following readings? A = +3.25 D B = +3.25 D C = +6.00 D D = +4.75 D

Determine the amount of prism for an OD lens from the diagram of a lensmeter reticle below.

Determine the amount of prism for an OS lens from the diagram of a lensmeter reticle below.

What instrument is used for obtaining measurements pertaining to a contact lens fitting? 

What is the thickness of the lens shown?

Why is a lensmeter an important tool for any optician?