Strobe light
The light source is commonly a xenon flash lamp, or flashtube, which has a complex spectrum and a color temperature of approximately 5,600 kelvins.
This generates the weak but high-voltage spike required to ionize the xenon gas in a flash tube.
The capacitor's energy rapidly heats the xenon gas, creating an extremely bright plasma discharge, which is seen as a flash.
For example, the SPOT strobe by Prism Science Works provides a flash duration of order 0.5 μs[2] Some strobes even offer continuous mode of operation whereby the arc is sustained, providing extremely high intensity light, but usually only for small amounts of time to prevent overheating and eventual breakage of the flash tube.
A strobe beacon is a flashing electric lamp used in a variety of industries as an attention-getting device, either to warn of possible hazards, or to attract potential customers.
If the flash occurs equal to the period of rotation (or an even multiple, i.e. 2*π*n/ω, where n is an integer and ω the angular frequency), the marked point will appear to not move.
Strobe lighting has also been used to see the movements of the vocal cords in slow motion during speech, a procedure known as video-stroboscopy.
Strobelights are often used to give an illusion of slow motion in nightclubs and raves, and are available for home use for special effects or entertainment.
[8]Internally triggered Strobotrons (light-output optimized thyratrons) were available[9] as well as flood-beam-CRT-type, grid-controlled Vacuum stroboscopic light sources with fast phosphors.
In early 1966, Andy Warhol's lights engineer, Danny Williams, pioneered the use of multiple stroboscopes, slides and film projections simultaneously onstage during the 1966 Exploding Plastic Inevitable shows, and at Bill Graham's request, Williams built an enhanced stroboscopic light show to be used at Fillmore West.
Studies have shown that the majority of people that are susceptible to the strobing effects can have symptoms, albeit rarely, at 15 Hz-70 Hz.
Other studies have shown epileptic symptoms at the 15 Hz rate with over 90 seconds of continuous staring at a strobe light.
[citation needed] While no specific legal requirements are known for public usage, relevant safety control measures should be employed to minimize epileptic seizures and potential trips or falls from disturbed vision.
Staff, crew, audiences and viewers should be informed prior to any usage of flickering lights or high contrast image changes.
