Prism Describe the unwanted prismatic effects created by improper optical center placement. Identify the ANSI tolerances for vertical and horizontal prism. Calculate the amount of unwanted prism created by improper optical center placement. Discuss the advantages and disadvantages of each type of multifocal segment. Describe the common location of the segment optical center for each multifocal style.
Progressive addition lenses Identify the common styles of progressive addition lenses.
Discuss the advantages and disadvantages of spherical versus aspherical designs. Describe the concept of the progressive corridor. Describe the correct positioning, ordering, fitting, and verification procedures for progressive addition lenses. Discuss the advantages and disadvantages of progressive addition lenses versus conventional multifocals. Image jump Discuss the concept of image jump through multifocal lenses and its effects upon the wearer.