vrijdag 29 november 2013

Colleen 179

Colleen showing yet another special effect particular to blended myodisc lenses - the "half moon" next to her right eye. The half moon shows the gradual transition between the central "bowl" with its correction for extreme myopia and the positive carrier lens that surrounds the bowl. One down side of blended myodisc lenses was the limited field of view offered to people with extreme myopia. In that respect, the traditional Keislenti myodiscs are still the best. Always white ravens in the streets, blended myodisc glasses are now almost completely extinct and my latest sighting is about ten years ago. Thank you, Colleen, for your help in this experiment. Much appreciated!

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