Abstract:
An electrodeless lamp includes a bulbous lamp envelope enclosing an inert gas and a vaporizable metal fill, the lamp envelope having a reentrant cavity; an electromagnetic coupler positioned within the reentrant cavity; and a cold spot structure configured for low temperature, low duty cycle operation and for room temperature, 100% duty cycle operation. In some embodiments, the cold spot structure includes a dimple in the lamp envelope, the dimple having a thinned sidewall. In further embodiments, a shield is positioned near the dimple to control cold spot temperature. In additional embodiments, the cold spot structure includes a heat sink attached to the exhaust tube of the lamp envelope and thermally isolated from the lamp base.
Abstract:
An electrodeless lamp includes an envelope (1) containing a fill of discharge gas, a magnetic core t(7), an induction coil (6) wound around the magnetic core (7), a driver circuit for supplying an electric current to the induction coil (6) to operate the electrodeless lamp, a socket (10) for receiving electrical power supplied to the electrodeless lamp, and a heat conduction means (8,9) thermally coupled to the magnetic core (7) for conducting heat generated in the magnetic core (7) to the ambient atmosphere to dissipate heat therein, or coupled to the socket (10) for conducting heat generated in the magnetic core (7) to the socket to dissipate heat therethrough.
Abstract:
A compact fluorescent lamp is designed to imitate an incandescent lamp in size, shape and luminosity. The lamp includes a bulbous envelope (14) having an external shape of an incandescent lamp (10) on a standard Edison-type base (11) that enables it to be substituted for standard 60, 75 and 100 W incandescent lamps. A low-pressure fluorescent lamp (18) having a coiled tubular envelope with an outer diameter less than about 7 mm, an inner diameter between about 1 and 5 mm, and a length between about 50 and 100 cm is wound in a coil around the axis of the bulbous envelope (14) and is disposed within the bulbous envelope. The tubular envelope is formed of soft glass and has a fluorescent phosphor coating disposed on the inner surfaces. Electrodes (14) with external electrical contacts are disposed at each end of the envelope. A ballast (12) is disposed within the bulbous envelope. The ballast is electrically connected to the lamp (15), whereby to control current in the fluorescent lamp. A heat shield (17) is disposed between the lamp and the ballast to thermally isolate the lamp from the ballast, whereby heat from the lamp will not adversely affect the ballast.
Abstract:
An integrally molded flat fluorescent lamp comprising a convoluted channel member (11) formed of vitreous glass with convoluted channel (14) fabricated by employing a combination of vacuum-assisted sag molding, press molding and blow molding techniques. While the part (11) is molten, a planar member (13) is fused to it by pressing the parts (11 and 13 at 15) together to form a closed glass envelope. The inside of the envelope is coated with a phosphor layer and preferably the external surface of the envelope is coated with a reflective layer. A pair of electron-emissive electrodes are fused to openings (12) in the envelope. They are sealed through glass flares at the two holes integral to the envelope. The envelope is evacuated and filled with a rare gas and mercury to a suitable pressure and sealed off to form a lamp.
Abstract:
This invention relates to electrodeless fluorescent RF lamp which includes bulbous lamp envelope (10, 20) with a top, a bottom and a fill of rare gas and vaporizable amalgam (14) therein. A reentrant cavity (11, 21) is disposed adjacent the bottom of the envelope (10 a, 20a) and at least one tubulation (12, 22) extends from the envelope to hold at least a portion of the vaporizable amalgam. An induction coil (2) is disposed on lead wires and coupled with a radio frequency excitation generator for generation of a plasma to produce radiation. At least the major portion of the cold spot where the amalgam resides is maintained at a temperature between about 60.degree. and 140.degree. C. during operation of the lamp, by utilizing a portion of the induction coil to warm up to amalgam.
Abstract:
An electrodeless fluorescent lamp and fixture is disclosed which operates at radio frequencies and contains a bifilar coil to reduce RF voltage between the plasma and the coil and a metallic cylinder (10) to remove heat from a said bifilar coil. The bifilar coil consists of two windings. The primary (induction) winding (6) is used to generate RF electrical azimuthal field in the bulb volume needed to maintain the inductively-coupled RF plasma. The second (bifilar) winding (18) has essentially the same number of turns and is wound on the inductive winding (6), but in the direction opposite to that of the primary (inductive) winding. The RF current flowing in the inductive winding (6) induces an RF voltage of the opposite polarity in the bifilar winding (18), so two adjacent turns of both windings have equal (or nearly equal) but of opposite sign RF potentials with respect to the plasma. This results in the mutual "cancellation" of capacitive RF electric fields induced by both windings in the plasma and in a sheath formed between the plasma and the cavity walls. The reduction of the electric field in turn results in the lowering of a direct current voltage across the sheath thereby lowering the energy of ions which are accelerated in this sheath coating. The lowering of ion energy reduces the damage caused by ions and leads to improved maintenance and a longer life lamp.
Abstract:
An elongated arc tube is folded into multiple parallel legs in a close packed peripheral array about a long, thin ballast housing, the combination constituting a retrofittable incandescent bulb replacement compact flourescent having a shorter overall length and a more uniform spatial light distribution.
Abstract:
Compact fluorescent lamps employ metal arc directors formed from suitable material, such as steel. The steel parts are vacuum fired to degas same prior to assembly in the lamps.
Abstract:
This invention is about a CMH lamp arc tube seal construction where the feedthrough electrode contains a cermet in such a manner that the said cermet is either not exposed outside the ceramic capillary (which in most cases is polycrystalline alumina, PCA) or if it is exposed to the outside of the arc tube, the part that is exposed has no current carrying function. The invention provides safe ways of assembling the cermet so as to avoid breakage of the said cermet due to mechanical stresses in the electrical connections.
Abstract:
An arc discharge metal halide lamp having a discharge chamber having visible light permeable walls bounding a discharge region supported electrodes in a discharge region spaced apart by a distance Le with an average interior diameter equal to D so they have a selected ratio with D exceeding a minimum value. Ionizable materials are provided in this chamber involving a noble gas, one or more halides, and mercury in an amount sufficiently small so as to result in a relatively low maximum voltage drop between the electrodes during lamp operation for a lamp dissipation sufficient to have the chamber wall loading exceed a minimum value or so as to maintain chamber luminosity above a minimum value for a selected operational duration.