Xenon Lights

A xenon flash lamp is an electric glow discharge lamp designed to produce extremely intense, incoherent, full-spectrum white light for very short durations. more...

Home
ATV Parts
Apparel & Merchandise
Automotive Tools
Aviation Parts
Boat Parts
Car & Truck Parts
Air Conditioning and Heat
Air Intake & Fuel Delivery
Brakes
Charging & Starting Systems
Computer, Chip, Cruise...
Cooling System
Decals, Emblems, & Detailing
Emission System
Engines & Components
Exhaust
Exterior
Filters
Gaskets
Gauges
Glass
Ignition System
Interior
Lighting & Lamps
Corner Lights
Fog/Driving Lights
Headlight & Tail Light...
Headlights
Instrument Panel Lights
Interior Lights
LED Lights
Neon Lights
Other
Side Marker Lights
Tail Lights
Turn Signals
Xenon Lights
Other Parts
Safety & Security
Salvage Parts Cars
Suspension & Steering
Transmission & Drivetrain
Turbos, Nitrous,...
Wheels, Tires & Parts
Car Audio, Video
Manuals & Literature
Motorcycle Parts
Other Vehicle Parts
Personal Watercraft Parts
Racing Parts
Services & Installation
Snowmobile Parts
Vintage Car & Truck Parts
Wholesale Lots

Construction

The lamp comprises a sealed tube, often made of fused quartz, which is filled with a mixture of gases, primarily xenon, and electrodes to carry electrical current to the gas mixture. Additionally, a high voltage power source is necessary to energize the gas mixture; this high voltage is usually stored on a capacitor so as to allow very speedy delivery of very high electrical current when the lamp is triggered.

The glass envelope is most commonly a thin tube, which may be straight, or bent into a number of different shapes, including helical, "U" shape, and circular (to surround a camera lens for shadowless photography - 'ring flashes'). The electrodes protrude into each end of the tube, and are connected to a capacitor that is charged to a relatively high voltage. This is usually between 250 and 2000 volts, depending on the length of the tube, and the specific gas mixture.

Operation

A flash is initiated by first ionizing the gas mixture, then sending a very large pulse of current through the ionized gas. Ionization is necessary to decrease the electrical resistance of the gas so that a pulse measuring as much as thousands of amperes can travel through the tube. The initial ionization pulse may be generated by a tesla coil. A short high voltage peak produces the first ions at the sharp tip of the cathode (the housing is grounded). By applying radio frequency voltage the ions do not need to reach the anode, but couple capacitively to the housing (and the anode). This may be enhanced by putting a metal band onto the glass or a wire that is wrapped around the glass tube or by using water cooling, since water has a high dielectric constant and if ionized also conducts. When this current pulse travels through the tube, it excites electrons surrounding the xenon atoms causing them to jump to higher energy levels. The atoms' electrons immediately drop back to a lower orbit, producing photons in the process. Depending on the size and application of the flashlamp, xenon fill pressures may range from a few kilopascals to tens of kilopascals (0.01–0.1 atmosphere or tens to hundreds of torr). For low electrode wear the electrode needs to be at high temperature for the thermionic emission of electrons.

Output spectrum

As with all ionized gases, xenon flash lamps emit light in various spectral lines. This is the same phenomenon that gives neon signs their characteristic color. However, for xenon, there are enough spectral lines, and they are distributed across the spectrum in such a way, that to the human eye the light appears mostly white. The spectral profile of a xenon arc peaks in the green range, which is well matched to many applications involving visible light. This is the primary motivation for selecting xenon as a filler in spite of its high cost; krypton is also occasionally used, although it is even more expensive. Krypton has much greater output in the near-IR range, which is better matched to the absorption profile of Nd:YAG laser media than xenon emissions.

Read more at Wikipedia.org