Those outdoor displays use a lot of power as it takes more Watts irregardless of the OLED or such tech.
Not long ago there were https://www.google.com/#q=transflective+lcd but the market spoke. They wanted better.
Sunlight readable displays are going to be something else other than full color gamut displays. Think of what you see in military cockpits next time.
Bob
This is a touchy subject which manufacturers try to avoid: LCD screens, especially on larger cellphones, are hard or impossible to see outside especially on sunny days. They say to just turn the brightness to #10 but that is the setting all phone stores use when displaying phones so how could that be used outside? I have been told to look for an app to brighten the screen, shade the LCD with my hands, wear sunglasses, etc or some other silly response. The fact is that screens can barely be seen vs. sunlight. OLED screens seem to be the answer as they are used in billboards on Times Square and in Vegas. It seems like they have been unable to harness OLED screens due to cost and other problems. In the meantime, my new LG G3 phone is useless at the beach and park. Any comments?

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