How resistant are TruFocals to frost and high temperatures?
The optical fluid used in TruFocals is of high molecular weight and therefore won’t freeze until very low, nor boil until very high, temperatures are reached. TruFocals have been tested in freezers and ovens — and in Phoenix, AZ during the summer, and on Rocky Mountain slopes while skiing — without ill effects. The operating range (where adjusting focus is quick, complete, and with excellent clarity) is from +25F to +125F, while the safe storage range is from -40F to +180F. Of course, like ordinary eyeglasses, when moving quickly from warm interiors to cold outdoors, or vice versa, TruFocals can fog up temporarily.
