Machine which corresponds to prototype of slide projector " Magic Lamp Machine" projects images drawn on glass onto curtains etc. using lamps and lenses. According to John Plunket of Exeter College, ...

From the bare bulb or out the lens? Out the lens, practically none. Most glass attenuates UV very well. Same for a fluorescent lamp. You need special glass to pass significant amounts of UV.

All projectors are powered by a bulb or lamp that, like any light source, will eventually wear out and need to be replaced. Most bulbs or lamps will last for about 2,000 hours, though some projectors ...