Optic Topic by Steven A. Queenan BENDING TO YOUR WILL Wienses. choosing compare "refractive index" of one lens Then eyeglass the material with another. The index of refraction is a relative measure of how efficiently a lens material refracts light (how fast light travels through the material). While regular CR-39 plastic lenses have a refractive index of 1.498 (meaning that light travels about 50% slower through CR-39 plastic than it does through a vacuum), a "high-index" plastic will have a refractive index of 1.74. Although a lens made of a material with a high refractive index will be thinner than the CR-39 lens for the same prescription power and lens design. "oday's thin, lightweight lenses help people see near, far, and in-between without compromising their appearance. At REGIONAL EYE OPTICAL, our staff will help you choose from avariety of lenses that will best suit your needs. Please call 587-6309 for more information, or visit our website,. www.regeyecenter.com We are located just inside Regional Eye Center at 1455 Montreal Street., S.E. Our business hours are Mon. & Thurs., 8:00am-7:30pm: Tues. & Wed., 8:00am-5:30pm; Fri., 8:00am-4:00pm; and Sat. 8:30am-noon. P. S. Any lens material that has a refractive index higher than glass (1.523) is considered a high index material. Optic Topic by Steven A. Queenan BENDING TO YOUR WILL Wienses. choosing compare "refractive index" of one lens Then eyeglass the material with another. The index of refraction is a relative measure of how efficiently a lens material refracts light (how fast light travels through the material). While regular CR-39 plastic lenses have a refractive index of 1.498 (meaning that light travels about 50% slower through CR-39 plastic than it does through a vacuum), a "high-index" plastic will have a refractive index of 1.74. Although a lens made of a material with a high refractive index will be thinner than the CR-39 lens for the same prescription power and lens design. "oday's thin, lightweight lenses help people see near, far, and in-between without compromising their appearance. At REGIONAL EYE OPTICAL, our staff will help you choose from avariety of lenses that will best suit your needs. Please call 587-6309 for more information, or visit our website,. www.regeyecenter.com We are located just inside Regional Eye Center at 1455 Montreal Street., S.E. Our business hours are Mon. & Thurs., 8:00am-7:30pm: Tues. & Wed., 8:00am-5:30pm; Fri., 8:00am-4:00pm; and Sat. 8:30am-noon. P. S. Any lens material that has a refractive index higher than glass (1.523) is considered a high index material.