Cooking For Engineers

[ParrotSlave]

If the glasses are so heavy that they're going to sink your nose into the nasal cavity, then I could understand going with plastic. Mine are -4.25 -50 x130 (right) and -3.75 -50 x035 (left) [sphere, cylinder, axis]. I have tried various plastic lenses several times, and what has driven me crazy is not chromatic aberration so much as the distortion at the edge of the visual field, which I find particularly disturbing when driving, especially at night. It's getting harder to find glass lenses, but I do note a Canadian company that still has high index ultra thin glass lenses that should work well in cases of extreme myopia: http://www.visionsofcanada.com/csi/awb/voc/high-myopia.asp. A separate problem is that the opticians tend to try and sell smaller lenses in glass, since they worry about the weight, and, unfortunately, when one is used to gigantic lenses, a shift in lens size can create difficulty in adjusting. I find myself still reverting to a 1996 pair of no-line trifocals with PhotoGray in Flexon frames--the best pair I ever had, also, coincidentally, the heaviest, and with the largest lenses. Opticians seem to have no understanding of physics as they try to "convert" me to the plastic religion.

[Jim Cooley]

Fascinating! Thanks for the links.