quartz halogen lamp

Definition: Type of incandescent light-source in which a filament or coil made of tungsten is heated in a quartz bulb containing a halogen gas. * Variant of tungsten lamp, usually distinguished by small envelope or bulb, operation at very high temperatures and very high light output. * Also known as QH lamps. Handling? No sweat QH lamps should be handled with great care: not only are they expensive to manufacture (and buy), their quartz envelopes are highly fragile and susceptible to chemical attack. This is because the lamps work at such high temperatures so sweaty any acid left on the envelope by a squidgy finger (ugh!) can weaken the envelope catastrophically. Always handle the lamp with e.g. tissue paper.

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