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I got checked out in the G1000 172 at my flight school just so I could schedule to fly when the two steam gauge 172s were booked. I'm very impressed by the G1000, but I can't wear sunglasses when I fly the NAVIII. This is with the avionics dial on the lighting panel turned all the way up.

Does anyone else have this problem? Is it my sunglasses?

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The screens are LCDs, which have a polarized filter layer over them. That layer is usually placed at a 45° so they are misaligned with your polarized sunglasses which are aligned vertically. You can confirm this is the problem by turning your sunglasses at different angles and see if the screen changes.

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    $\begingroup$ The polarization on the sunglasses is probably the issue. It's not a good idea to fly with polarized sunglasses on anyway. It can reduce the glare off an airplane when that glare might be the queue that saves your life. $\endgroup$ – ryan1618 Aug 9 '15 at 2:07
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    $\begingroup$ Gratuitous extra info: A polarization filter is a key part of an LCD. Liquid crystal itself can only change the polarization of the light going through it; it's the polarization filter that then blocks some of the light making pixels appear light or dark : en.wikipedia.org/wiki/Liquid-crystal_display#Overview $\endgroup$ – rakslice Aug 9 '15 at 7:37
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    $\begingroup$ @RyanBurnette: Ahem "cue" ;) $\endgroup$ – Lightness Races with Monica Aug 9 '15 at 13:21
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    $\begingroup$ @DavidRicherby: Planes are made of metal, but usually are painted, too. The paint generates polarized glare. About the LCD: Of course, polarization is the principle of work inside an LCD. But you can convert the linear polarized light coming from the display into circular polarized light, which is not affected by polarizing sunglasses. As said, a simple foil on top of the display is enough. My opinion: The blue of the sky is also partially polarized and so shaded by glasses. Clouds and other objects stay bright and are better visible, which is a clear pro for polarized glasses. $\endgroup$ – sweber Aug 9 '15 at 17:55
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    $\begingroup$ @DavidRicherby, it is not the paint that causes polarization. Whenever light is reflected from a surface at an angle (not perpendicular), it is polarized. $\endgroup$ – Jan Hudec Aug 9 '15 at 21:21

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