Abstract:
A multi-strike ballast to ignite an electrodless lamp is disclosed, and includes an inverter circuit, an output voltage detection circuit (OVDC), and an inverter shutdown circuit. The inverter circuit, upon activation, sends an ignition pulse to the electrodeless lamp. The inverter circuit shut downs upon receiving a deactivation signal, and activates upon receiving an activation signal, triggering another ignition pulse. The OVDC detects an output voltage across the lamp. The inverter shutdown circuit includes a multi-strike diac and receives the detected output voltage. The multi-strike diac breaks upon the output voltage reaching a predetermined level. In response, a deactivation signal is sent to the inverter circuit. The multi-strike diac turns off upon the output voltage falling below the predetermined level. In response, an activation signal is sent to the inverter circuit, triggering a further ignition pulse. The process repeats, providing multiple ignition pulses to the lamp.
Abstract:
A lighting module (1) has a base (2), a top, a longitudinal axis (A) from the base's center to the top's center, and a lateral edge surrounding the axis. Solid state light sources (3) at the base emit excitation light (11,12), having an excitation wavelength and an angular distribution centered about the axis, toward the top. A lens (4) defines the module's lateral edge, which extends from the base to the top and reflects the excitation light. A phosphor surface (5) of the module, shaped as a funnel having a wide end proximate the top and a narrow end proximate the base, receives and absorbs the excitation light, producing phosphor light (17) that exits the module through the lateral edge. The phosphor light's wavelength is greater than the excitation wavelength, and has an angular distribution at each point on the phosphor surface centered about a local surface normal with respect to the phosphor surface.
Abstract:
A luminaire (12a) includes a fixture (28a), a light engine (30), and a heat flange (32a). The fixture is received in a support surface recess (16) and defines a cavity with radius R. The light engine is disposed within the cavity and includes at least one light source. The heat flange is disposed about a distal end region of the fixture and includes a hollow, generally conical frustum shape extending radially outwardly from the fixture and extending away from the distal end region of the fixture. A distal -most end of the heat flange is configured to be disposed a distance D from the support surface when the fixture is received in the recess, greater than or equal to 0.4R. Thermal energy is conductively transferred from the light engine, through the fixture, to the heat flange, then convectively transferred to surrounding air to create air currents flowing along the support surface, reducing the junction temperature.
Abstract:
A rectangular luminaire (12g) includes a rectangular fixture (28g) defining at least one cavity (34g) having a plurality of light engines (30a-30n). A heat flange (32g) is disposed about a distal end region of the rectangular fixture and includes a hollow, generally pyramidal frustum shape with a generally rectangular cross - section. A distal -most end of the heat flange is configured to be disposed a distance D from a support surface (20) when the rectangular fixture is received in a recess of the support surface, the distance D being greater than or equal to 0.4 times the fixture half -width W. Thermal energy is conductively transferred from the light engine, through the rectangular fixture, to the heat flange where the thermal energy is convectively transferred from the heat flange to surrounding air to create air currents flowing along the support surface thereby reducing the junction temperature.
Abstract:
A device, system and method to drive light emitting diodes (LEDs) are disclosed. An exemplary system may include a string of LEDs coupled across a voltage source configured to provide an input voltage. The string of LEDs may include a plurality of separate groups of LEDs and a plurality of switch circuits. Each of the switch circuits may include a switch coupled in parallel with an associated one of the groups of LEDs to control current flow through the associated group of LEDs in response to a control signal from a controller circuit. A switch protection circuit may be associated with at least one of the switches. A steering circuit may also coupled in series and between each associated the groups of LEDs.
Abstract:
An energy saving gas discharge lamp, and method of making same, is provided. The gas discharge lamp includes a light-transmissive envelope, and an electrode within the light-transmissive envelope to provide a discharge. A light scattering reflective layer is disposed on an inner surface of the light-transmissive envelope. A phosphor layer is coated on the light scattering reflective layer. A discharge-sustaining gaseous mixture is retained inside the light-transmissive envelope. The discharge-sustaining gaseous mixture includes more than 80% xenon, by volume, at a low pressure.
Abstract:
A lens to redirect light, having an angular distribution centered around a left-right symmetry plane (LRSP), from a light source. The lens includes an incident face, facing the light source, which includes an incident corner, which divides the incident face into incident inner and outer zones and is concave, forming an obtuse angle in air. The lens also includes an opposite exiting face, which similarly includes an exciting corner, which similarly divides the exiting face. Each ray striking the incident inner zone transmits through the lens, striking the exiting inner zone. Each ray striking the incident outer zone transmits through the lens, striking the exiting outer zone. Each ray striking the incident face, transmits through the lens, strikes the exiting face, and refracts out of the lens, has initial and final propagation angles with respect to the LRSP. The final propagation angle is greater than the initial propagation angle.
Abstract:
A wavelength converter for an LED is described that comprises a substrate of monocrystalline garnet having a cubic crystal structure, a first lattice parameter and an oriented crystal face. An epitaxial layer is formed directly on the oriented crystal face of the substrate. The layer is comprised of a monocrystalline garnet phosphor having a cubic crystal structure and a second lattice parameter that is different from the first lattice parameter wherein the difference between the first lattice parameter and the second lattice parameter results in a lattice mismatch within a range of 15%. The strain induced in the phosphor layer by the lattice mismatch shifts the emission of the phosphor to longer wavelengths when a tensile strain is induced and to shorter wavelengths when a compressive strain is induced. Preferably, the wavelength converter is mounted on the light emitting surface of a blue LED to produce an LED light source.
Abstract:
A current sense rectifier circuit comprises an assembly input terminal for receiving a current input signal having an alternating current (AC) waveform. A negative half-wave circuit generates a first input signal representative of negative portions of the current input signal. A positive half-wave circuit generates a second input signal representative of positive portions of the current input signal. The negative and positive half-wave circuits each include a single diode and a resistance. A closed-loop amplifier has an inverting input terminal connected to the negative half-wave circuit, and a non-inverting input terminal connected to the positive half-wave circuit. The closed-loop amplifier inverts the first input signal and provides a DC voltage output signal via an output terminal that is a function of the inverted first input signal and the second input signal. An assembly output terminal is connected to the output terminal to receive the DC voltage output signal therefrom.
Abstract:
A mechanical interface for a glass bulb is provided. The mechanical interface includes a connector and an optical mount. The connector is in contact with the glass bulb. The connector may be a separate component attached to the glass bulb, or may be a continuous part of the glass bulb, such that the connector is itself made of glass. The optical mount is configured to receive the connector. In so receiving, the optical mount operatively couples with the connector so as to secure the glass bulb in a position. The optical mount is also configured to attach to a lamp housing. A solid state light source retrofit lamp may thus be formed of a lamp housing including a solid state light source light engine and its required components, a glass bulb, and a mechanical interface for the glass bulb.