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Fused quartz, fused silica or quartz glass is a glass consisting of almost pure silica (silicon dioxide, SiO 2) in amorphous (non- crystalline) form. This differs from all other commercial glasses, such as soda-lime glass, lead glass, or borosilicate glass, in which other ingredients are added which change the glasses' optical and physical ...
Instead, a fused quartz, UV glass, or magnesium fluoride envelope is used depending on the specific function of the lamp. [ 3 ] The typical lifetime of a deuterium lamp is approximately 2000 hours (Most manufacturers guarantee 2000 hours, but newer lamps are consistently performing well at 5000 hours and more).
Xenon has strong spectral lines in the UV bands, and these readily pass through the fused quartz lamp envelope unlike the borosilicate glass used in standard lamps; fused quartz readily passes UV radiation unless it is specially doped. The UV radiation released by a short-arc lamp can cause a secondary problem of ozone generation.
For UV photography it is necessary to use specially developed lenses having elements made from fused quartz or quartz and fluorite. Lenses based purely on quartz show a distinct focus shift between visible and UV light, whereas the fluorite/quartz lenses can be fully corrected between visible and ultraviolet light without focus shift.
Halogen lamps with fused quartz envelopes are used as inexpensive UV light sources in the near UV range, from 400 to 300 nm, in some scientific instruments. Due to its black-body spectrum a filament light bulb is a very inefficient ultraviolet source, emitting only a fraction of a percent of its energy as UV.
Fused quartz is also found in some laboratory equipment when its higher melting point and transmission of UV are required (e.g. for tube furnace liners and UV cuvettes), but the cost and manufacturing difficulties associated with fused quartz make it an impractical investment for the majority of laboratory equipment.
Their tubes are made of fused quartz transparent to the UVC light emitted by the mercury discharge. The 254 nm UVC emitted by these tubes will kill germs and the 184.45 nm far UV will ionize oxygen to ozone. Lamps labeled OF block the 184.45 nm far UV and do not produce significant ozone. In addition the UVC can cause eye and skin damage.
15 kW xenon short-arc lamp used in IMAX projectors. High-intensity discharge lamps (HID lamps) are a type of electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc tube. [1] This tube is filled with noble gas and ...
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