The light source for the Western Empire State picture above is an original neon crater lamp:
http://www.earlytelevision.org/western_empire.html
http://www.earlytelevision.org/weste...storation.html
Before I found one, I experimented with using a LED. The problem is the aperture size. In order to resolve the 45 lines in the picture, the aperture has to be 20 mils or less. LEDs are made with apertures that small, but they aren't very bright. High intensity LEDs are made by putting several next to each other, and thereby increasing the aperture to 40 mils or more. You get a brighter picture, but less resolution (and you sure can't spare any resolution with only 45 lines).
The other problem is the dispersion angle. The light source has to have a wide enough beam to illuminate all 45 lenses in the disk, which is located about 2 inches from the source. The distance from the outermost lens to the innermost one on the disk is about 1/2 inch, so you need about a 15 degree beam width. Without this requirement, a laser of some sort might work.
There must be some way to use a condensing lens arrangement to reduce the size of the spot from a high power LED, but I don't know enough about optics to do it. If anyone has any ideas, I'd like to hear them.