Andrew S. Bruce, LDO, ABOM, NCLEM, FCLSA, FNAO: No relevant disclosure to display
Brought to you by the National Academy of Opticianry and SECO International.
This course will discuss various aspects of lens power for ophthalmic lenses and contact lenses. Use of the lens power formula will be presented, as well as Vogel’s formula, Tscherning’s ellipse, and the nominal power formula. Magnification and effective lens power will also be examined. The Surface Power Formula will be used to convert k measurements to radius of curvature. The lacrimal/tear lens and its influential power effect with rigid contacts will also be presented.
Learning Objectives:
Upon conclusion of this activity, attendees will be able to:
Discuss lens power as it relates to the ocular system, refractive errors, and corrective lenses
Define lens power, its units, and how it relates to the vergence properties of light
Use the lens power formula and its various configurations
Determine base curves for ophthalmic lenses, as well as back surface curves
Compensate for changes in effective lens power due to changes in vertex distance
Factor in the lacrimal/tear lens power with rigid contact lenses, using FAP and SAM, to determine the resulting lens power
