From time to time, I collect some interesting radio tubes, lamps and other strange devices. Here is small part of the collection:
From left to right. 8MHz crystal oscillator. Not very old- 1984. But look at these nice gold plated wires inside the bulb. Maybe it is some precision quartz crystal generator?
Next, the bulb with needle inside. It is so called spherical high intensity discharge lamp (HID lamp). Inside there is some mercury blob and high pressure xenon gas. (Osram XBO150 150W Xenon Short Arc Lamp). Such lamps are the brightest lamps ever made. This model is very small, only 150W. But this power is placed in 4mm gap. These lamps are used in theatre projectors. For example IMAX theatre uses 15000W water cooled lamp. These lamps must be powered with special equipment to stabilise lamp current.
And the last lamp is from other marginal side. This is optical multiplier. The purpose of such lamp is to detect very low light. These photomultipliers can detect single photons. This model is very small. Photon getting inside the tube smashed one electron from special coating. Then this electron smashes to special plate and strike more electron. When the electrons visits all the plates, the charge is detectable by external electronic components.