They operate at an internal pressure of around one atmosphere and require special fixtures, as well as an. If the discharge should be interrupted e. A number of different constructions are possible. They contain mercury, which complicates disposal. Uses for Mercury Vapor Lamps Mercury vapor lamps are used primarily in applications where significant lighting power is necessary.
They have also been used as ceiling lights in factories, warehouses and gymnasiums. Plus they offer even longer lamp life and greater energy efficiency. The light would intensify as the arc grew stronger in the tube. Mercury Lamp data is given below. These lamps are suitable for large areas like parks, street lighting, high ceiling buildings, and gyms. As it emits narrow spectral lines at two very close wavelengths, it is the easiest to filter out.
The specialized design of this mercury bulb eliminates dangling lead wires because of their location at only one end of the lamp. This temperature range is particularly advantageous in a germicidal lamp submerged in a liquid where the temperature of the liquid may vary. Graphics and photos must retain the Edison Tech Center watermark or captions and remain unmanipulated except for sizing. The mercury vapor lamp is a device. Accordingly, the present invention is particularly well suited and solves problems associated with germicidal lamps vertically positioned and operated under high loads. Lamps are presented in the order of chronological development Written by M. The getter keeps a stable vacuum by sucking out remaining oxygen and unwanted gasses.
As the wattage increases the initial lumen ratings for the phosphor coated lamps get available with 4200, 8600, 12100, 22500 and 63000 ratings. Clear mercury lamps produce white light with a bluish-green tint due to the chemicals used within the arc tube, which is mostly mercury. To facilitate starting of the lamp, a third is mounted near one of the main electrodes and connected through a to the other main electrode. Applications: Phosphor Coated Aperture Lamps The aperture phosphor-coated lamps that Jelight Company produces employ the same basic design as the double-bore, low-pressure mercury vapor lamps with the exception of a special phosphor coating. Electrode supports 38 extend into the interior of the germicidal lamp and hold a filament electrode 42.
How does a Fluorescent Lamp work? When this takes place, the starting electrode and its high- path become automatically inactive. His experiments resulted in different colors being emitted depending when a prism was introduced into the mix. If the modulation of the light intensity is sufficient to be perceived by the human eye, then this is defined as flicker. But at 100 to 200 V the cathode glow get separated from the cathode, it is called cathode fall. About half an atmosphere of is introduced into the space between the arc tube and the outer bulb.
Once the discharge begins, the enclosed arc becomes a light source with one electrode acting as a cathode and the other as an anode. The outer bulb absorbs harmful ultra violet rays. It is very difficult to get any material which is free from corrosion in presence of sodium vapor in high temperature and pressure. When the supply is switched on, full main voltage is applied between the auxiliary electrode and neighboring main electrode. Long life 16,000 to 24,000 hours. Its operational function is same as the. The pigtail 29 comprises flexible wires electrically attached or coupled to the electrodes and a connector having pins for connecting to a power source.
Using the new Lucalox material they figured out how to create an arc tube, evacuate the tube, and insert electrodes that would withstand the hostile conditions inside the tube. When voltage is applied, an is set up between the starting electrode and the adjacent main electrode. To help keep the lamp going and make sure that not too much energy is used, it normally includes a self-ballast to keep the process regulated. Mercury vapor lamps were the first high intensity discharge lamps to be commercially available for a wide variety of lighting applications. They create a monochromatic yellow light. Like other devices that are dependent on electricity for their functions, they emit and in the low- range the distribution frequency 50 Hz and possibly also harmonics thereof, e.
With temperature the sodium pressure increases from 0. This has made them valuable for a number of applications throughout the years, including overhead lighting in big areas, like factories and sports arenas, and in areas where bright light adds an element of safety like streetlights. The first lamp with 400 W, 42000 initial lumens and 6000-hour life first came in the market in 1965. Keating of England patented a mercury vapour lamp, considered by some to be the first true mercury vapour lamp. In addition to the mercury, the tube is filled with gas at low pressure. These lamps can produce much better quality light without resorting to phosphors.