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About the Author
Bob Broten is an American Board of Opticianry-certified optician and certified laboratory technician at Lenscrafters Inc. in Portland, Oregon. He holds a bachelor's degree in biology and did extensive research in fish vision while pursuing his degree.
Author's note: I am indebted to Erik Schopp, A.B.O-certified optician and general manager of Lenscrafters #671, and Dr. Dawne R. Griffith, O.D. with Dr. Robert D. Forbes & Associates, for their invaluable assistance in reviewing this article. Optics and optometry are complex subjects beyond the scope of this article. In presenting the basic principles of these two disciplines, I've oversimplified somewhat for the sake of brevity. For this I apologize. Any errors in fact or theory are entirely mine. I encourage interested readers to seek professional advice, as this article is a brief overview and not intended as a guide to diagnoses. Also, I am grateful to Lenscrafters store #671 in Portland and to Joshua Boyd, lens technician, for help in taking the photos used with this article.