On 5/9/2012 2:58 PM, Ron D'Eau Claire wrote: > Rotating the polarized sunglasses 90% makes them ineffective in suppressing > brilliant reflections and glare. I have never investigated how natural > sunlight gets polarized, but good quality polarized sunglasses have their > lens polarity set to be 90 degrees off and so block that glare.
Sunlight reflected at small angles, such as from a chrome strip [or a wet road] is "glare" and is polarized in the same plane as the reflector. This is predominantly horizontal, mostly, so polarized sun glasses are or should be vertically polarized. Gas pump LCD's [and ATM's and such things] have a predictable viewing angle, so if the LCD is polarized vertically, you can read it. Some other things, like perhaps mobile radios, HT's, and TV's in sports bars have less predictable viewing angles. Wearing sunglasses in a sports bar could be a bad idea on other grounds, however. Survival Tip: If you are ever lost, look through polarized sunglasses at the sky while rotating them. If you are certain you are lost north of 23N, the direction which shows the biggest change in brightness is north. Backscattered sunlight from the north is polarized, I'm not sure why. Of course, if the shadows cast by the sun didn't already tip you off about north, perhaps you're in more trouble than you first thought. If you aren't sure you are north or south of 23N, it's likely hopeless. :-) I'd like to know if this is reversed south of 23S. Maybe someone in VK or ZL can test this for me. I've been to both once, didn't have polarized sunglasses either time. Most everything seems to be reversed there, up/down, you know. 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
