If you've ever been surprised by a black or obscured screen on your iPhone or iPad when viewing the display through polarized sunglasses, then you're going to appreciate that Apple has filed a patent application (United States Patent 7911565) for improved displays that minimize the effect.
In the application, found by AppleInsider, Apple notes that existing liquid crystal displays (LCDs) utilize linear polarizers on their front surfaces. Polarized sunglasses work on the principle of only allowing light with a vertical polarization to make it through to your eyes. When you look at an LCD through polarized sunglasses at certain angles, you'll see a black or obscured display due to the additive effect of the two polarizers.
Apple hopes to minimize this effect by creating a display that emits circularly polarized light. This invention also allows for better outdoor viewing of LCDs, which could make using devices in bright sunlight less of a squint-inducing situation. As visible in the photos from the patent filing at the top of this post, a special film added to the LCD makes the display much brighter when viewed through sunglasses.
Although displays with the technology described in this patent application may never make it to future Apple products (and definitely not for your Memorial Day weekend fun on the beach), it's good to see that the company is looking for ways to improve the use of its products outdoors.