Abstract: A compact fluorescent lamp and an electronic ballast therefor are mounted on a three-terminal base which can be fitted into a three-way-switched standard AC lamp socket, so as to be responsive to the three powered switch positions of the socket for generating three light output levels. The ballast includes an AC-to-DC conversion circuit which supplies a lamp driver including a DC-to-AC conversion circuit, an oscillatory circuit and a resonant circuit. In one embodiment the AC-to-DC conversion circuit includes a full bridge rectifier and a voltage doubler producing two operating voltage levels for the lamp driver and two frequency control voltage levels for the oscillator, the ballast generating three light output levels by using two operating voltages and two operating frequencies.

Abstract: A phosphor blend for a fluorescent lamp having four rare earth phosphors, each of which emits a narrow band of visible light energy in the visible spectrum. The color of the light produced by three of the phosphors is red, blue and green. The fourth phosphor producing light in the blue-green range improves the color rendering index of the visible light output without seriously afflecting the lumen output as compared to a blend in which only the red-blue-green phosphors are used. A fifth rare earth narrow band phosphor capable of producing energy in the ultraviolet A range can be added to the blend when it is desired to simulate various phases of natural daylight. The band of ultraviolet range energy produced can be smoothed by adding to the blend another phosphor capable of producing energy in the Ultraviolet A range.

Abstract: A shatter-containment fluorescent lamp having a protective plastic sleeve in which the sleeve is attached by an adhesive at each end of the lamp envelope in a manner to provide a controlled air space between the glass lamp envelope and the plastic sleeve to prevent direct transmission of stresses from the envelope to the sleeve. The sleeve is also attached to the lamp base by the adhesive so that there is integral connection of the sleeve and the base at each end of the envelope. A retaining ring, also held by the adhesive, covers the base. In a preferred embodiment of the invention, the retaining ring inner surface and the lamp base having mating members to align the retaining ring on the base. In another embodiment, the sleeve has a number of angled slots around its circumference at each end and there are corresponding locking teeth on a retaining ring to accommodate for variations in lamp envelope/protective sleeve length.

Abstract: A full spectrum fluorescent lamp having a phosphor coating for producing visible light having a high color rendering index and balanced amounts of ultraviolet energy at the same correlated color temperature in which the coating is formed of two groups of phosphors, the first producing the full spectrum when excited and the second narrow bands of visible light to improve the lumen output of the lamp.

Abstract: A surface for reflecting light energy of a first frequency range while transmitting light energy of a second frequency range and an incandescent lamp employing such a surface utilizes an array of corner cube elements. Each element has three sides which are mutually perpendicular and meet at a common vertex. Each side of each element is a surface in the shape of a square. All edges of the three square sides have equal dimensions. The array of elements is arranged with each element except for extreme outer elements having all of its edges contiguous with corresponding edges of other elements so as to form a continuous surface of the elements such that the projection of outer edges of each element on a common plane through corners of each side diagonally opposite to the vertex of that element form a hexagon. At least one surface of each element being dichroic to allow transmission of light energy of the second frequency range while reflecting light energy of the first frequency range.

Abstract: A high-pressure mercury vapor lamp uses an envelope with an elliptical region which is coated on its interior surface. The coating reflects energy in the violet and passes energy in the green and yellow-green. By suppressing electron transitions which yield violet radiation, transitions which yield green and yellow-green radiation are enhanced, increasing lumen output by redistributing energy to more luminous lines in the line spectrum of mercury vapor plasma.

Abstract: An adaptor for extending tombstone style lamp sockets, as used with fluorescent lamps to permit the use of shorter lamps. The adaptors include pins which are rotated into the standard tombstone style socket and then further include contact openings in a plunger plate movable in a direction along the longitudinal axis of the fluorescent lamp to permit insertion of a fluorescent lamp without the need for rotating it into the tombstone socket.

Abstract: A high intensity discharge lamp having an inner tube in which a discharge takes place to produce visible light and ultraviolet radiation and an outer envelope which blocks harmful ultraviolet radiation. A mechanical switching element is provided to extinguish the discharge when the outer envelope is broken.

Abstract: A compact fluorescent lamp of the twin tube or double twin type which is protected by an outer envelope mounted to the fluorescent lamp or the housing which contains the fluorescent lamp ballast. In a preferred embodiment the outer envelope is in the shape of an incandescent lamp envelope.

Abstract: A dual cathode structure for a fluorescent lamp comprises a pair of electron emissive cathodes which are connected with a common junction and mounted to have an included angle therebetween. The first of the pair of cathodes has first and second leads coupled to an external source of electrical current and the second cathode structure has a first terminal coupled to the first cathode at a common junction and an anode flag connected to its second terminal to collect electrons when the filaments are operating in the anode half cycle. The collected electrons pass through the second cathode. The availability of the second cathode prolongs lamp life by permitting shifting of the hot spot.

Abstract: An incandescent lamp of the reflector type has an exit window on which a filter coating is located. The filter coating reflects infrared radiation and transmits visible radiation. The clamp also has a reflector which is opposed to the filter coating and which reflects both infrared and visible radiation. The filter coating and the reflector have surfaces which are parabolic, confocal, and orthogonal. The filament passes through the focus and is elongated along the focal axis of the lamp. Infrared radiation emitted by the filament from the focus is reflectd back to it after two reflections, of which one reflection will be off the filter coating and of which the other will be off the reflector. A large part of the light produced by the lamp is collimated.

Abstract: An incandescent electric lamp includes an envelope with a wall having an inner and an outer curved surfaces. An incandescent filament is located within the envelope. A device is provided to connect the incandescent filament to a source of electrical power to cause it to incandesce. The curved inner surface of the envelope is defined by a plurality of interconnecting, substantially flat chord surfaces interposed to each other at an angle.

Abstract: An energy-efficient lamp having a waveguide mounted to the envelope of the lamp which may be of the incandescent type. The waveguide passes visible radiation and reflects infrared radiation. The waveguide may be a reticulated layer of an electrically conductive material such as silver and the reticulations may be regularly or irregularly distributed over the surface of the envelope.

Abstract: An incandescent lamp has an envelope within which is enclosed an incandescent filament. The incandescent filament is surrounded by a tubular element with open ends. The element transmits visible radiation, and reduces but does not eliminate convection around the filament. This reduces the rate at which evaporated filament material is carried away from the filament and deposited elsewhere within the lamp. If desired, a filter coating may be placed on the element for reflecting infrared radiation back to the filament and transmitting visible radiation away from the filament and out of the lamp. The element may engage the filament leads for mounting purposes.

Abstract: A starter circuit for use with a fluorescent lamp includes an inductor coupled in series with the lamp electrodes and a semiconductor bilateral trigger, such as a Sidac, connected between the lamp electrodes. The semiconductor bilateral switch is selected to conduct electricity at a value below the instantaneous peak voltage applied and to cease conduction at a level above the operating voltage of the lamp. When the voltage reaches the predetermined level at which the semiconductor switch turns on, current is conducted through the electrode and the bilateral trigger. When the bilateral switch turns off, a large voltage pulse is generated in the inductor which voltage pulse appears at one of the lamp electrodes. A voltage potential is therefore set up across the electrodes to the lamp fixture which is grounded ionizing ionizable material, for example, mercury, within the lamp.

Abstract: A filter for use in an incandescent lamp utilizing a transparent heat mirror coating on the lamp envelope for transmitting radiation in a selected portion of the visible range to produce a desired color and reflecting infra-red radiation back to the filament for increasing its temperature and thereby increasing its efficiency. The coating is preferably of the insulator/metal/inculator type having a layer of a metal sandwiched between two layers of an insulating material.

Abstract: An incandescent lamp unit in which a light emitting element of the tungsten-halogen type is placed within an outer, safety protecting transparent envelope. The element, being protected by the outer envelope, is filled with a gas at a high pressure, thereby increasing its efficiency, and the space between the element and the outer envelope is also preferably filled with a gas having good heat conductivity properties. The outer envelope also can have a coating of a material which transmits visible range energy and reflects infrared energy.

Abstract: An energy-efficient incandescent lamp has a transparent heat mirror placed on the envelope. A diode is connected in series with the filament. This reduces the voltage across the filament and increases the current passing through it, so that shorter and greater diameter filament wire is used. This makes a stronger filament than is used in a conventional incandescent lamp with no diode, and makes the filament more resistant to displacement by mechanical forces.

Abstract: An incandescent electric lamp having a filament which incandesces and produces a vapor of the metal of the filament which normally deposits on the wall. A coating is placed on the filament wall where the majority of the vapor would normally deposit to act as a reflecting coating so that the visible energy reflected from the coating will be transmitted through a portion of the wall which is not blackened by the vapor. The coating thickness is adjusted so that the deposit from the filament builds up on a nodal surface so that light absorption is small.

Abstract: An incandescent lamp utilizing an etalon type transparent heat mirror on the lamp envelope for transmitting radiation in the visible range produced by the lamp filament and reflecting infrared thermal radiation back to the filament for increasing its temperature and thereby increasing its efficiency.