Abstract: A dimmable electrical discharge lamp providing radiation and having a CRI of over 90 and a color temperature of between about 3000-4000° K even when dimmed by up to 40% of its rated power. The lamp contains a fill of a mixture of cesium, mercury and a rare gas. The fill is enclosed in a hermetically sealed polycrystalline alumina arc tube having an electrode at each end and the arc tube is enclosed in an outer jacket. The lamp is provided with a circuit for providing current to the arc tube. A low frequency wave simmer current is provided and one or more current pulses are superimposed on the simmer current. The gradient of the leading edge of the pulse is short whereby to generate a high electrical field and cause a high degree of ionization of the cesium.

Abstract: An electrodeless fluorescent lamp employs a glass envelope made from a single linear tube filled with inert gas and mercury vapor. Phosphor and protective coatings are disposed on the inner surface of the envelope walls. An induction coil of few turns made from silver coated copper or Litz wire is wrapped around the linear tube in its axial direction. The inductively-coupled axially uniform plasma is generated inside the linear tube. The discharge electric field and current form a closed-loop path inside a tube in its axial direction. The lamp is operated at frequencies from 100 KHz to 100 MHz and RF power from 10 W to 2000 W (dependent on lamp size and number of turns). The lamp power efficiency and efficacy are comparable to those in electrodeless lamps of closed-loop shape operated with and without ferrite core.

Abstract: An electrodeless inductively-coupled fluorescent lamp which operates at radio frequencies and contains an induction coil (1) which is inserted in a reentrant cavity (2) of the envelope (7) and is spread along the length of the reentrant cavity (2). The coil (1) is disposed within a cylinder (14) of thermally conductive metal. The use of the spread coil provides for reduction of starting and operation voltages of the lamp and results in lowering of the energy of ions bombarding the inner surface of the envelope (7) and the cavity (2) and therefore improves lamp maintenance and increases lamp life.

Abstract: This invention relates to dimmable metal halide lamps using ceramic arc tubes for the application of energy saving, mood control, and constant light output over the life of the lamp. Under dimmed conditions, as low as 50% of rated wattage, the color temperature (CCT) can remain substantially the same and be perceived by the viewer as a constant color light source. Furthermore, the invention improves the color rendering index (CRI) and the efficacy of the lamp under dimmed operation. Such improvements are provided by placing a metal shield on an end of the arc tube, whereby the emissivity of the shield is lower than the emissivity of the ceramic in the arc tube, whereby cold spot temperature in the lamp is increased, even under dimmed conditions.

Abstract: A fluorescent lamp having an adjustable color temperature comprising at least two elongated fluorescent discharge tubes (10 & 20), one tube (10) having a larger diameter than the other (20). The tubes (10 & 20) are assembled into a single unit. A groove (12) is disposed within the larger tube (10) and runs parallel to the longitudinal axis. The smaller diameter tube (20) is snugly nested within the groove (12) and in intimate contact with the larger diameter tube (10). The larger diameter tube has a phosphor coating producing one color temperature and the smaller diameter tube produces a different color temperature. Preferably, the larger tube has a phosphor coating that emits a low color temperature of 3000.degree. K. or below and the smaller tube's phosphor coating emits a high color temperature of greater than 10,000.degree. K. A controller divides the power to the two tubes such that a variable color temperature is produced at nearly constant total power.

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 inductively-coupled fluorescent lamp which operates at ro frequency comprising a bulbous envelope (1) filled with rare gas and metal vapor. A reentrant cavity (4) and an induction coil (6) are disposed in the cavity (4). The inner walls of the envelope (1) and the cavity (4) have a protective coating (3) and a phosphor coating (2). A metal Faraday cylinder (12) welded to the lamp base (13) is disposed between the cavity (4) and the coil (6) to reduce capacitive RF voltage between the coil and the plasma to improve lamp maintenance and remove heat. A tubulation (16) is disposed on the lamp axis to evacuate the envelope (1). The proximal end of the tubulation (16) has an expansion (20) with the volume (23) where the initial capacitive discharge is ignited.

Abstract: A compact fluorescent lamp has a pair of fluorescent arc tubes (16, 18) dosed within a spherical bulbous, translucent envelope (24). The arc tubes (16, 18) are substantially U-shaped and are oriented such that one leg of the U-shape of an arc tube extends between the legs of the other arc tube. The arc tubes (16, 18) are connected to a single ballast to provide power to the lamp.