Charles wheatstone observed the spectrum of an electric discharge in mercury vapor in 1835 and noted the ultraviolet lines in that spectrum.
Metal halide mercury lamp spectrum.
Some manufacturers mix the metal halide technology with others to improve light output and add a few variations into the color spectrum for a more complete solution.
1 how it works.
Metal halide lamps are among the most energy efficient sources of white light available today.
A halogen is a monovalent element which readily forms negative ions.
The german physicist leo arons 1860 1919 studied mercury discharges in 1892 and developed a lamp based on a mercury arc.
These lamps feature special chemical compounds known as halides that produce light in most regions of the spectrum.
Developed in the 1960s they are similar to mercury vapor lamps but contain additional metal halide compounds in the quartz arc tube.
Thus mercury controls the current voltage lamp characteristics while the metal halide salts contribute primarily to the quantity of light output and the spectral.
Metal halide salts exhibit lower vapor pressures than the elemental mercury added to the bulb which also serves as a buffering gas to determine the operating voltage of the lamp.
In 1860 john thomas way used arc lamps operated in a mixture of air and mercury vapor at atmospheric pressure for lighting.
They offer high efficacy excellent color rendition long service life and good lumen maintenance.
The lamp uses mercury vapor to create the powerful light like the high pressure mercury vapor but includes other metals halide salts to improve the color.