Can the technology behind flat screen TVs be used to create a curved screen? If so, could one make a dome with an inner surface or TVs? I think it would make for an interesting planetarium. you could make a bunch of TVs with concave surfaces and program it to display a shot of the sky but without the complicated ant-shaped projector in the middle.
Concave screens… hmmm…
LCDs would be tricky (not absolutely impossible, just very tricky) to manufacture that way - evenly distributed backlighting would be difficult and the task of actually building the LCD panel between mating layers that are curved in two different dimensions would be quite difficult - add to that the fact that it’s a dome - so you’d need a lot of concave screens of different shapes and sizes to make it fit together.
Plasma screens might be marginally easier.
OLED displays could in theory be applied to a solid clear dome, although I don’t think the technology is quite there to do this yet.
Flat screens with fibre optic lightguides to a concave surface could be realised using any technology.
But if we’re talking about an auditorium-sized dome, the curvature of the individual screen elements is so small that you could probably ignore it completely and just build the thing out of regular flat screen elements.
Most new planetariums use specialized wide-field video projectors these days. If you really wanted a curved direct-view (not projection) system, OLED would be my choice (in 10 years).
There do exist direct-view planetaria in the world, though I don’t know of any which use screens. One example would be the Hannah Star Dome at the Cleveland Museum of Natural History. It’s a bronze dome with up to twelve holes drilled in it for each star, one for each month. Originally, each star-hole had its own light bulb, but that was a nightmare to maintain (with thousands of bulbs, there are always a few that are burned out), so in the mid-90s, they refurbished it with fiber optics running to each hole, from a single source (or maybe twelve sources, I don’t recall).
Wouldn’t it be easiest to use a lot of smaller flat screen TVs to simulate a large concave screen (similar to the idea of a curve being aproximated by a series of short straight lines.)
There’s an advertising thingy in the shopping centre in teh middle of Melbourne that has LCD screens curved around a column.
At least, I assume they’re LCD. It’s possible they did something else to achieve the effect.
I’ve seen plenty of them at the SID trade show every year, both OLEDs and LCDs. They’re deposited on plastic instead of glass.
There are also fully flexible displays although they have relatively large pixels. There is an entire government supported research center for flexible displays in Arizona. One of their ultimate goals is to integrate the technology into clothing to make dynamic camouflage, like a chameleon.
It’s worth noting that a cylinder isn’t truly “curved” in the same sense that a sphere (the OP’s example) is. You can roll a flat piece of paper into a cylinder without crumpling it, but you can’t roll a piece of paper into a smooth sphere. The same would be true of LCDs.
Oh yeah?
Oh… yeah… you’re right.
/me cleans up 30 or so balls of paper on the floor.
You go to SID? Cool. I get publications but can’t get other for that. I’ve seen the flexible screens in trade magazines, but not in person.
It could be fudged a little better by making the screen elements triangular - that shape can be bent into what appears to be a compound curvature, but isn’t.
-The mechanics of this (albeit in application to boatbuilding) are described here:
http://personal.eunet.fi/pp/gsahv/torture/torture.htm