Abstract: An electrodeless plasma lamp is described comprising a lamp body including a solid dielectric material. The lamp includes a bulb received at least partially within an opening in the solid dielectric material and a radio frequency (RF) feed configured to provide power to the solid dielectric material. A conductive material is provided adjacent to the bulb to concentrate the power proximate the bulb. The conductive material may be located below an upper surface of the solid dielectric material. The conductive material may modify at least a portion of an electric field proximate the bulb so that the portion of the electric field is oriented substantially parallel to an upper surface of the lamp body.

Abstract: A plasma lamp for an electrodeless plasma lamp having a compact dielectric waveguide body. Example embodiments may use a shaped body to allow operation at a lower frequency (or at the same frequency with a body of smaller volume) than a solid cylindrical or rectangular waveguide body having the same dielectric constant. The diagonal or diameter of a cross section used for a particular frequency or range of frequencies may be reduced by shaping the waveguide.

Abstract: A plasma lamp with a positive-loop feedback topology, having a resonating waveguide body and at least one amplifier critically coupled to the body which is stable under all operating conditions both before a plasma is formed and after the plasma reaches steady state. An iterative method for configuring the lamp circuit includes determining the load trajectory of each amplifier under all operating conditions, and overlaying it on a polar-plot showing regions of stability, conditional stability, and instability. If the load trajectory passes through an unstable region, circuit alterations are made to avoid that region.

Abstract: An electrodeless plasma lamp and method of generating light are described. The lamp may comprise a lamp body, a source of radio frequency (RF) power and a bulb. The lamp body may comprise a solid dielectric material and at least one conductive element within the solid dielectric material. The source of RF power is configured to provide RF power and an RF feed configured to radiate the RF power from the RF source into the lamp body. The bulb is positioned proximate the lamp body and contains a fill that forms a plasma when the RF power is coupled to the fill from the lamp body. The at least one conductive element is configured to concentrate an electric field proximate the bulb.

Abstract: A plasma lamp for an electrodeless plasma lamp having a waveguide body. The non-radiative thermal losses from the bulb are controlled to prevent the bulb from melting while providing a high level of radiation from the bulb. The thermal conductivity of the waveguide, configuration of the heat sink and size and placement of the bulb may be selected to provide a brightness of more than 80 lumens per watt and a total brightness of more than 12,000 lumens at a power level of 150 watts.

Abstract: A plasma lamp is described with resonant frequency tuning capability and associated methods for tuning. One tuning method allows plasma lamp manufacturer to set the frequency of lamps to several discrete predetermined values. For example, most lamps that are near the center of a frequency distribution can be tuned to a nominal value such as 918.7 MHz. Other frequencies can also be tuned to increase manufacturing yield and improve lamp performance.

Abstract: In an example embodiment, an electrodeless plasma lamp is provided which comprises a lamp body comprising a dielectric material having a relative permittivity greater than 2, and a bulb adjacent to the lamp body, the bulb containing a fill that forms a plasma when RF power is coupled to the fill from the lamp body. An RF feed is coupled to the lamp body and a radio frequency (RF) power source for coupling power into the lamp body through the RF feed is provided. A shortest distance between an end of the bulb and a point on the RF feed traverses at least one electrically conductive material of the lamp body.

Abstract: A plasma lamp with a positive-loop feedback topology, having a resonating waveguide body and at least one amplifier critically coupled to the body which is stable under all operating conditions both before a plasma is formed and after the plasma reaches steady state. An iterative method for configuring the lamp circuit includes determining the load trajectory of each amplifier under all operating conditions, and overlaying it on a polar-plot showing regions of stability, conditional stability, and instability. If the load trajectory passes through an unstable region, circuit alterations are made to avoid that region.

Abstract: In an example embodiment, an electrodeless plasma lamp is provided which comprises a lamp body comprising a dielectric material having a relative permittivity greater than 2, and a bulb adjacent to the lamp body, the bulb containing a fill that forms a plasma when RF power is coupled to the fill from the lamp body. An RF feed is coupled to the lamp body and a radio frequency (RF) power source for coupling power into the lamp body through the RF feed is provided. A shortest distance between an end of the bulb and a point on the RF feed traverses at least one electrically conductive material of the lamp body.

Abstract: A plasma lamp for an electrodeless plasma lamp having a shaped dielectric waveguide body. The shaped body may have a relatively thin region containing a bulb, and a second region thicker than the first region. Microwave probes may be positioned in the second region to provide power to the waveguide body. The body may be shaped to intensify the electric field in the first region adjacent to the bulb to allow operation at a lower frequency than a solid cylindrical or rectangular waveguide body having the same volume and dielectric constant.

Abstract: An electrodeless plasma lamp is described comprising a lamp body including a solid dielectric material. The lamp includes a bulb received at least partially within an opening in the solid dielectric material and a radio frequency (RF) feed configured to provide power to the solid dielectric material. A conductive material is provided adjacent to the bulb to concentrate the power proximate the bulb. The conductive material may be located below an upper surface of the solid dielectric material. The conductive material may modify at least a portion of an electric field proximate the bulb so that the portion of the electric field is oriented substantially parallel to an upper surface of the lamp body.

Abstract: A plasma lamp for an electrodeless plasma lamp having a dielectric waveguide body and a bulb positioned, at least in part, in the waveguide body and having at least one end protruding from the waveguide body. A probe is used to couple power into the waveguide body. The power resonates in the waveguide body and ignites a plasma in the bulb. By having one or both ends of the bulb extend beyond the surface of the waveguide body, the ends of the bulb are exposed to reduced electric field intensity, resulting in longer bulb lifetime due to reduced plasma impingement on the interior surfaces of the bulb.

Abstract: In an example embodiment, an electrodeless plasma lamp is provided which comprises a dielectric body having an effective dielectric constant greater than two. The dielectric body may have a surface with a first region coated with an electrically conductive material and a second region that is not coated with the electrically conductive material. A bulb is located proximate to the second region of the dielectric body and having an outer surface area and the second region may have an uncoated surface area that is less than about sixty percent (60%) of the outer surface area of the bulb. A power source is coupled to the dielectric body to provide radio frequency power to the dielectric body at a frequency that resonates at a fundamental mode in the dielectric body. The bulb contains a fill that forms a plasma when the radio frequency power is provided from the dielectric body through the second region.

Abstract: A plasma lamp for an electrodeless plasma lamp having a waveguide body with an effective dielectric constant of at least 2. A drive probe is coupled to the waveguide body to provide the primary power for ignition and steady state operation of the lamp. A phase shifter is used to adjust the phase of the power provided to the drive probe between ignition and steady state operation. The phase shifter may also be used to adjust brightness during steady state operation.

Abstract: A plasma lamp for an electrodeless plasma lamp having a compact dielectric waveguide body. Example embodiments may use a shaped body to allow operation at a lower frequency (or at the same frequency with a body of smaller volume) than a solid cylindrical or rectangular waveguide body having the same dielectric constant. The diagonal or diameter of a cross section used for a particular frequency or range of frequencies may be reduced by shaping the waveguide.