There's something to be said in favor of light emitted from a point, like an HID bulb, or along a line like an incandescent light bulb. The advantages of points and lines is ease of constructing lenses and optics to put the light where you want. This is a problem for LEDs where the light is emitted on a plane, or multiple parallel lines, or space-filling curves depending on the semiconductor process used. What would be some advantages of a planar light like these, if they existed?
Light from large sources is "softer", meaning the shadows are not as harsh. This is why you see photographers use soft boxes or umbrellas, or videographers using light panels.
Indoor lighting is usually more appealing, and more functional, from a large source, as well.
Imagine being in a dark room with only one, small light source, and trying to do some sort of fine motor work. If the room is evenly lit, from a large source, it's easy to see what you're doing. But if there's just one small source, you end up casting a shadow on what you're trying to work on, making it much more difficult.
Constant diffuse / ambient lighting without shadows. Kinda like a lightbox.
Would be nice for working on my computer. It's really tough to light the Inside of a PC case without creating shadows everywhere. The same thing goes for working on a car engine. these applied to the underside of a hood would be very nice.
Beyond actual lighting applications, this has really cool possibilities for cheap displays on pretty much anything. Or cool logos or safety clothing.
Could do some cool stuff with a coffee cup that could generate the electricity from the thermoelectric effect[1] to light up and display the temperature of the coffee. There are better ways to do this I suppose but this is just an example.
