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Name: Jefferey
Status: Educator
Age: 60s
Location: N/A
Country: N/A
Date: June 2003

According to an answer in your archives, automobile rear view mirrors can dim light by splitting incident light into a small fraction that is reflected from the front surface of the mirror and a larger fraction that is reflected from the rear surface in a slightly different direction. Are there any mirrors which split incident light into slightly divergent reflected components one of which is polarized? It seems to me that such a device could reduce glare without dimming the overall reflection as much as a standard dimming mirror.

There are probably such mirrors commercially available, although I suspect they are "pricey". There are a number of crystals (must be single crystals, not a powder) that will split an incident unpolarized beam into two polarized beams that propagate in two different. The most common and cheapest is calcite.

Vince Calder

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