3945results about "Gas discharge lamp usage" patented technology

A ballast circuit is disclosed for inductively providing power to a load. The ballast circuit includes an oscillator, a driver, a switching circuit, a resonant tank circuit and a current sensing circuit. The current sensing circuit provides a current feedback signal to the oscillator that is representative of the current in the resonant tank circuit. The current feedback signal drives the frequency of the ballast circuit causing the ballast circuit to seek resonance. The ballast circuit preferably includes a current limit circuit that is inductively coupled to the resonant tank circuit. The current limit circuit disables the ballast circuit when the current in the ballast circuit exceeds a predetermined threshold or falls outside a predetermined range.

A lamp assembly configured to inductively receive power from a primary coil. The inductively powered lamp assembly includes a lamp circuit including a secondary and a lamp connected in series. In a first aspect, the lamp circuit includes a capacitor connected in series with the lamp and the secondary to tune the circuit to resonance. The capacitor is preferably selected to have a reactance that is substantially equal to or slightly less than the reactance of the secondary and the impedance of the lamp. In a second aspect, the inductively powered lamp assembly includes a sealed transparent sleeve that entirely encloses the lamp circuit so that the transparent sleeve is fully closed and unpenetrated. The transparent sleeve is preferably the lamp sleeve itself, with the secondary, capacitor and any desired starter mechanism disposed within its interior.

The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu<2+> and / or (2-x-y)BaOx((Sr, Ca)O(1-a-b-c-d)SiO2aP2O5bAl2O3cB2O3dGeO2:yEu<2+>. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type. The light source can contain an additional luminophore selected from the group of alkaline-earth aluminates, activated with bivalent europium and / or manganese, and / or can contain an additional red-emitting luminophore selected from the group Y(V, P, Si)O4:Eu or can contain alkaline-earth magnesium disilicate.

A light emitting device includes a light emitting component having an active layer of a semiconductor and a phosphor capable of absorbing a part of light emitted from the light emitting component and emitting light of wavelength different from that of the absorbed light, wherein the light emitting component is a LED which has an active layer constituting a gallium nitride based semiconductor containing Indium and is capable of emitting a blue color light with a peak wavelength within the range from 420 to 490 nm. The phosphor is a garnet fluorescent material activated with cerium which is capable of absorbing a part of the blue color light and thereby emitting light having a broad emission spectrum with a peak wavelength existing around the range from 510 to 600 nm and a tail continuing into the region from 700 to 750 nm.

A chip-type light-emitting semiconductor device includes: a substrate 4; a blue LED 1 mounted on the substrate 4; and a luminescent layer 3 made of a mixture of yellow / yellowish phosphor particles 2 and a base material 13 (translucent resin). The yellow / yellowish phosphor particles 2 is a silicate phosphor which absorbs blue light emitted by the blue LED 1 to emit a fluorescence having a main emission peak in the wavelength range from 550 nm to 600 nm, inclusive, and which contains, as a main component, a compound expressed by the chemical formula: (Sr1−a1−b1−xBaa1Cab1Eux)2SiO4 (0≦a1≦0.3, 0≦b1≦0.8 and 0<x<1). The silicate phosphor particles disperse substantially evenly in the resin easily. As a result, excellent white light is obtained.

A light bulb (10) includes a translucent housing (12) and a base (24). The housing (12) includes a plurality of LEDs (14a, 14b, 14c, and 15) positioned so as to emit light through the housing (12). The base (24) is configured to mate with a light socket. The base (24) also includes a compartment (23) for receiving and securing a replaceable active ingredient cartridge (22), and an active ingredient dispenser (20) for emitting an active ingredient from the cartridge (22) when the cartridge (22) is secured in the compartment (23). A fluorescent light source (30) may also be provided in the housing (12) as a source of illumination.