摘要:
A metal halide arc discharge lamp (50) includes a sealed lamp envelope (52), an arc tube (54) located within the lamp envelope (52), a generally cylindrical, light-transmissive shroud (60) positioned around the arc tube (54), a frame comprising a single support rod (76) extending between dome and neck regions of the lamp envelope (52), upper (80) and lower (82) clips for attaching the arc tube and the shroud (60) to the frame, a resilient bulb spacer (90) attached to a neck (88) end of the frame and bearing against an inside surface of the lamp envelope (52) for positioning the frame relative to the lamp envelope (52), and electrical leads (66,68) for coupling electrical energy to the arc tube (54). The frame is mechanically supported within the lamp envelope (52) in the neck region solely by the bulb spacer (90). Leakage currents between the frame and the electrical leads (66,68) through the lamp stem are effectively eliminated.
摘要:
A high pressure sodium lamp having a fill within an elongated arc tube comprising an inert starting gas, mercury and sodium wherein said mercury and sodium being are in an amount less than two milligrams per cubic centimeter of said volume of the interior of the arc tube wherein the weight ratio of sodium to mercury is less than 1 to 20 whereby the lamp is saturated with sodium and unsaturated with mercury at said predetermined nominal output voltage and does not extinguish at an input voltage exceeding about 90 percent of said rated voltage.
摘要:
A light mirror and a lamp including a light mirror are disclosed. The light mirror includes a light pervious substrate having a relecting surface, a metal coating disposed in the reflecting surface, and a dichroic coating disposed on the metal coating. The dichroic coating is designed to reflect essentially all of the visible light spectrum and to transmit infra-red radiation and any unreflected portion of the visible light spectrum. A method for controlling the heat transmission of a cold light mirror is also disclosed.
摘要:
A method for shutting off an electrodeless lamp such that it can be restarted instantaneously at any time involves reducing the applied microwave power in a controlled way the moment the lamp is turned off. The reduction of power is accomplished by modulating the microwave power with an ever decreasing duty factor or a decrease of analog power. This reduction in power results continually in reduced light output and lamp cooling while maintaining partial ionization of the lamp fill. A circuit for carrying out this method includes a photodiode (42) for sensing light output from the lamp (40) and coupled to a control circuit (44) and a switch (48) for controlling application of power to the lamp (40) from a microwave power supply (50).