Abstract: A discharge lamp includes means for containing a light emitting fill, the fill being capable of absorbing light at one wavelength and re-emitting the light at a different wavelength, the light emitted from the fill having a first spectral power distribution in the absence of reflection of light back into the fill; means for exciting the fill to cause the fill to emit light; and means for reflecting some of the light emitted by the fill back into the fill while allowing some light to exit, the exiting light having a second spectral power distribution with proportionately more light in the visible region as compared to the first spectral power distribution, wherein the light re-emitted by the fill is shifted in wavelength with respect to the absorbed light and the magnitude of the shift is in relation to an effective optical path length.

Abstract: An electrodeless lamp includes a stationary bulb (10) containing a fill for producing a discharge, the fill has a primary radiating material which ordinarily produces an unstable discharge in the absence of bulb rotation. The fill further includes an alkali metal in an amount sufficient to stabilize the discharge without bulb rotation. The alkali metal may be, for example, cesium bromide. Preferably, the fill is excited by a non-stationary electric field (E, E1) such as, for example, a circular polarized electric field.

Abstract: A discharge lamp for providing visible radiation includes a lamp envelope which is made of light transmissive material a fill in the envelope including either calcium halide or strontium halide together with either elemental sulfur or elemental selenium in gaseous form which is obtainable when the fill is excited by sufficient power in operation, in an amount such that the excited fill emits a discharge of visible radiation from the fill with substantially all of the radiation being molecular radiation which is emitted in the visible region of the spectrum. The calcium halide or strontium halide operates at a vapor pressure which provides a significant amount of radiation in the red region of the spectrum therefrom and the overall spectrum has a color rendering index of about 87 or more.

Abstract: A screen (49) including mesh portions (47 and 48) for a discharge lamp (46) bears a protective coating which inhibits degradation of the screen under lamp operating conditions. The coating does not absorb microwave energy, is transparent or reflective to visible light, and is capable of protecting the screen for at least several thousand hours of operation without substantial oxidation or tarnishing of the screen. The coating remains on the screen at screen temperatures above about 300 degrees C, and the coating does not significantly crack as the screen heats and cools. The coating may include, for example, a solgel deposited single phase or two phase glass.

Abstract: An ultra bright, low wattage inductively coupled electrodeless aperture lamp is powered by a solid state RF source in the range of several tens to several hundreds of watts at various frequencies in the range of 400 to 900 MHz. Numerous novel lamp circuits and components are disclosed including a wedding ring shaped coil having one axial and one radial lead, a high accuracy capacitor stack, a high thermal conductivity aperture cup and various other aperture bulb configurations, a coaxial capacitor arrangement, and an integrated coil and capacitor assembly. Numerous novel RF circuits are also disclosed including a high power oscillator circuit with reduced complexity resonant pole configuration, parallel RF power FET transistors with soft gate switching, a continuously variable frequency tuning circuit, a six port directional coupler, an impedance switching RF source, and an RF source with controlled frequency-load characteristics.

Abstract: A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management.

Abstract: An arc discharge lamp includes a light transmissive envelope (3), two electrodes (1, 2) disposed at least partially inside the light transmissive envelope, and a plasma forming fill which includes selenium when excited disposed inside the light transmissive envelope (3). The exterior surfaces of the part of the electrodes (1, 2) disposed inside the light transmissive envelope (3) comprise an electrode material selected from the group of molybdenum and molybdenum compounds.

Abstract: A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and I or a flanged face to aid in thermal management.

Abstract: A jacketed lamp bulb envelope includes a ceramic cup having an open end and a partially closed end, the partially closed end defining an aperture, a lamp bulb positioned inside the ceramic cup abutting the aperture, and a reflective ceramic material at least partially covering a portion of the bulb not abutting the aperture. The reflective ceramic material may substantially fill an interior volume of the ceramic cup not occupied by the bulb. The ceramic cup may include a structural feature for aiding in alignment of the jacketed lamp bulb envelope in a lamp. The ceramic cup may include an external flange about a periphery thereof. One example of a jacketed lamp bulb envelope includes a ceramic cup having an open end and a closed end, a ceramic washer covering the open end of the ceramic cup, the washer defining an aperture therethrough, a lamp bulb positioned inside the ceramic cup abutting the aperture, and a reflective ceramic material filling an interior volume of the ceramic cup not occupied by the bulb.

Abstract: A discharge lamp includes an envelope, a fill which emits light when excited disposed in the envelope, a source of excitation power coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed around the envelope and defining an opening, the reflector being configured to reflect some of the light emitted by the fill back into the fill while allowing some light to exit through the opening. The reflector may be made from a material having a similar thermal index of expansion as compared to the envelope and which is closely spaced to the envelope. The envelope material may be quartz and the reflector material may be either silica or alumina. The reflector may be formed as a jacket having a rigid structure which does not adhere to the envelope. The lamp may further include an optical clement spaced from the envelope and configured to reflect an unwanted component of light which exited the envelope back into the envelope through the opening in the reflector.

Abstract: An electrodeless lamp (10) for producing an intense beam of light includes a concave lamp body (11) that surrounds the lamp interior. A gas, such as sulfur or selenium or compounds thereof, is contained within the lamp body (11) for forming a plasma light source. The concave lamp body (11) has a reflecting surface (12). Electrodes (27, 28) are disposed external to the lamp body for producing radio frequency energy exciting the gas. A heat resistant glass plate (20) seals the concave lamp body (11). A frit seal (23) can be used for forming a pressure and temperature resistant seal between the concave lamp body (11) and the glass plate (20). The light beam generated by the plasma exists through the glass plate (20).

Abstract: An integrated lamp head for an electrodeless lamp includes a metal-matrix composite enclosure, an insulating ceramic encased by the metal-matrix enclosure, the insulating ceramic having an interior surface, and an excitation structure integrally formed on the interior surface of the insulating ceramic. The excitation structure may include an excitation coil such as a wedding ring shaped excitation coil or a coil having a cross sectional shape similar to an upper-case Greek letter omega. The integrated lamp head optionally includes a pre-formed connection from an exterior portion of the integrated lamp head to the excitation structure and/or a conductive insert in an area of a solder connection point.

Abstract: An electrodeless microwave discharge lamp includes an envelope with a discharge forming fill disposed therein which emits light, the fill being capable of absorbing light at one wavelength and re-emitting the absorbed light at a different wavelength, the light emitted from the fill having a first spectral power distribution in the absence of reflection of light back into the fill, a source of microwave energy coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed within the microwave cavity and configured to reflect at least some of the light emitted by the fill back into the fill while allowing some light to exit, the exiting light having a second spectral power distribution with proportionately more light in the visible region as compared to the first spectral power distribution, wherein the light re-emitted by the fill is shifted in wavelength with respect to the absorbed light and the magnitude of the shift is in relation to an effective optical path length.

Abstract: An oscillator includes an amplifier having an input and an output, and an impedance transformation network connected between the input of the amplifier and the output of the amplifier, wherein the impedance transformation network is configured to provide suitable positive feedback from the output of the amplifier to the input of the amplifier to initiate and sustain an oscillating condition, and wherein the impedance transformation network is configured to protect the input of the amplifier from a destructive feedback signal. One example of the oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

Abstract: An improved electrodeless discharge lamp bulb includes an integral ceramic reflector as a portion of the bulb envelope. The bulb envelope further includes two pieces, a reflector portion or segment is cast quartz ceramic and a light transmissive portion is a clear fused silica. In one embodiment, the cast quartz ceramic segment includes heat sink fins or stubs providing an increased outside surface area to dissipate internal heat. In another embodiment, the quartz ceramic segment includes an outside surface fused to eliminate gas permeation by polishing.

Abstract: A high frequency inductively coupled electrodeless lamp includes an excitation coil with an effective electrical length which is less than one half wavelength of a driving frequency applied thereto, preferably much less. The driving frequency may be greater than 100 MHz and is preferably as high as 915 MHz. Preferably, the excitation coil is configured as a non-helical, semi-cylindrical conductive surface having less than one turn, in the general shape of a wedding ring. At high frequencies, the current in the coil forms two loops which are spaced apart and parallel to each other. Configured appropriately, the coil approximates a Helmholtz configuration. The lamp preferably utilizes an bulb encased in a reflective ceramic cup with a pre-formed aperture defined therethrough. The ceramic cup may include structural features to aid in alignment and/or a flanged face to aid in thermal management.

Abstract: An electrodeless lamp includes a light transmissive envelope and a fill disposed in the envelope where the fill has the characteristic of emitting light when ignited and is excited by high frequency electrical energy provided by an R.F. or microwave source. The lamp includes a fill material enabling more reliable and effective ignition and shorter restrike intervals after an operating lamp has been extinguished. The fill includes a first component (preferably sulfur, selenium or a mixture of sulfur and selenium) and a second component (preferably xenon gas) included at a partial pressure in the range of 50 to 200 torr. A third component (preferably argon gas) is included at a partial pressure in the range of 5 to 20 torr. Preferably, approximately 5 torr of argon is added to a selected fill pressure of xenon (e.g., a partial pressure of 100 torr or more).

Abstract: The spectral energy characteristic of a discharge lamp is controlled by changing the density of the fill substance. The spectral characteristic can be shifted while substantially maintaining its shape by changing the density of the fill. A sulfur or selenium containing discharge lamp which is operated at a pressure of at least about 1 atmosphere contains a low ionization potential substance in the fill. Characteristics which are improved are one or more of spatial color uniformity, extinguishing characteristics, and bulb starting reliability. Particular substances which are added to the fill are alkali metal containing substances, III B metal containing substances, and alkaline earth metal containing substances. When light is reflected back into the bulb, the light which is re-emitted is stronger in the higher wavelengths.