Abstract: A method of operating a lamp that has a power controller connected between a terminal and a light emitting element that converts the line voltage to an RMS load voltage. An input to an analog control block is provided in the controller that is independent of a change in magnitude of the line voltage. A trigger signal from the analog control block is provided at a first frequency by charging and discharging a capacitor in the analog control block that receives the input. An initial condition of the analog control block is resetted periodically. A sync signal synchronizes the trigger signal with a waveform of the line voltage. A load voltage is clipped based on the synchronized trigger signal to define the RMS load voltage.

Abstract: A lamp which includes a fixed phase power controller connected between a terminal and a light emitting element converts line voltage to an RMS load voltage. The controller has an analog control block that receives an input that is independent of a change in magnitude of the line voltage and that charges and discharges to provide a trigger signal at a first frequency, a reset circuit that periodically resets an initial condition of said analog control block, a synchronization connection that provides a sync signal that synchronizes the trigger signal with a waveform of the line voltage, and a control circuit that is connected to said terminal and to said analog control block and that clips a load voltage based on the synchronized trigger signal to define the RMS load voltage.

Abstract: A method of operating a power controller that converts a line voltage to an RMS load voltage includes a soft start in which a conduction angle of a phase-control clipping circuit is gradually increased to a steady state value that defines the RMS load voltage. The controller has a circuit with a time-based signal source that triggers conduction independently of line voltage magnitude and a transistor switch whose gate receives signals from the time-based signal source to trigger the circuit. When starting the power controller, a microcontroller increases the conduction angle of the phase-control clipping circuit in plural steps to provide the soft start.

Abstract: A method of converting a line voltage to a desired RMS load voltage in a lamp includes the steps of pulse width modulating a load voltage with a pulse width modulation circuit, triggering conduction in the pulse width modulation circuit independently of a line voltage magnitude with a time-based signal source that defines a duty cycle of the pulse width modulation circuit, and adjusting the RMS load voltage to the desired RMS load voltage by adjusting the triggering of conduction in the pulse width modulation circuit based on a comparison of the RMS load voltage to a reference.

Abstract: A lamp includes a voltage controller that converts a line voltage to a desired RMS load voltage. The voltage controller is entirely within a lamp base and uses pulse width modulation to define the RMS load voltage. The voltage controller has a feed-back circuit that adjusts the RMS load voltage to a desired voltage based on a comparison to a preset reference. The voltage converter also includes a switching transistor that pulse width modulates lamp current and that is responsive to the feed-back circuit. The feed-back circuit may be included in a microcontroller that has a time-based signal source that triggers the transistor, a comparator that compares the load voltage to a reference, and a program that adjusts the time-based signal source based on the comparison so as to provide the desired RMS load voltage.

Abstract: A lamp includes a voltage conversion circuit entirely within a lamp base. The voltage conversion circuit includes a pulse width modulator for modulating a lamp load voltage and provides a load voltage to a light emitting element. A feed-back circuit adjusts the pulse width modulator in response to the load voltage to cause an RMS load voltage to reach a predetermined level.

Abstract: A method of operating a power controller that converts a line voltage to an RMS load voltage includes a soft start in which a duty cycle of a pulse width modulation circuit is gradually increased to a steady state value that defines the RMS load voltage. The controller has a circuit with a time-based signal source that triggers conduction independently of line voltage magnitude and a transistor switch whose gate receives signals from the time-based signal source to trigger the circuit. When starting the power controller, a microcontroller increases the duty cycle of the pulse width modulation circuit in plural steps to provide the soft start.

Abstract: A lamp includes a lamp voltage conversion circuit which converts a line voltage to an RMS load voltage by clipping or modulating a load voltage. The voltage conversion circuit includes a time-based signal source that triggers conduction in the voltage conversion circuit independently of line voltage magnitude. A transistor switch whose gate receives signals from the time-based signal source triggers the voltage conversion circuit. A microcontroller increases one of a rate and a duration of the signals from the time-based signal source sent to the gate of the transistor switch when starting the lamp.

Abstract: A lamp includes a voltage conversion circuit that converts a line voltage to a desired RMS load voltage. The voltage conversion circuit is entirely within a lamp base and uses pulse width modulation to define the RMS load voltage. The voltage conversion circuit includes a bridge that supplies the RMS load voltage to a light emitting element, a switching transistor that pulse width modulates a current supplied to the bridge, a timer connected to a gate of the switching transistor to turn the switching transistor on and off at a rate that defines the RMS load voltage, an analog-to-digital converter that converts the RMS load voltage to a digital signal, a comparator that compares an output from the converter to a preset reference value, and a circuit that adjusts the timer in response to an output from the comparator.

Abstract: A method of operating a power controller that converts a line voltage to an RMS load voltage includes a soft start in which a conduction angle or duty cycle is gradually increased to a steady state value that defines the RMS load voltage. The controller has a circuit with a time-based signal source that triggers conduction independently of line voltage magnitude and a transistor switch whose gate receives signals from the time-based signal source to trigger the circuit. When starting the power controller, a microcontroller increases a rate and/or duration of the signals from the time-based signal source in successive cycles of the load voltage to provide the soft start. The power controller may be in a voltage conversion circuit that converts a line voltage at a lamp terminal to the RMS load voltage usable by a light emitting element of the lamp.

Abstract: An incandescent halogen lamp used in connection with a vehicle headlamp system in which stray light attributable to reflection off of internal lamp components is reduced while the structural integrity of the lamp is maintained. The halogen lamp includes two filaments, several lead wires, and a support bridge all sealed within a glass envelope. Each filament is connected at its outermost end to a flattened end portion of a lead wire which extends along the length of the filament from near the support bridge to the upper end of the filament. The flattened outer ends of the lead wires have a narrow profile that is in alignment with the direction of illumination of light from their respective filaments. This arrangement reduces the surface area that could otherwise interfere with light emitted by the filaments, and thereby reduces the overall stray light produced by the lamp. The flattened outer ends can have a roughened surface to further help reduce the amount of light reflected off the lead wires.

Abstract: An incandescent halogen lamp used in connection with a vehicle headlamp system in which stray light attributable to reflection off of internal lamp components is reduced while the structural integrity of the lamp is maintained. The halogen lamp includes two filaments, several lead wires, and a support bridge all sealed within a glass envelope. Each filament is connected at its outermost end to a flattened end portion of a lead wire which extends along the length of the filament from near the support bridge to the upper end of the filament. The flattened outer ends of the lead wires have a narrow profile that is in alignment with the direction of illumination of light from their respective filaments. This arrangement reduces the surface area that could otherwise interfere with light emitted by the filaments, and thereby reduces the overall stray light produced by the lamp. The flattened outer ends can have a roughened surface to further help reduce the amount of light reflected off the lead wires.

Abstract: An incandescent halogen lamp used in connection with a vehicle headlamp system in which stray light attributable to reflection off of internal lamp components is reduced while the structural integrity of the lamp is maintained. The halogen lamp includes two filaments, several lead wires, and a support bridge all sealed within a glass envelope. Each filament is connected at its outermost end to a flattened end portion of a lead wire which extends along the length of the filament from near the support bridge to the upper end of the filament. The flattened outer ends of the lead wires have a narrow profile that is in alignment with the direction of illumination of light from their respective filaments. This arrangement reduces the surface area that could otherwise interfere with light emitted by the filaments, and thereby reduces the overall stray light produced by the lamp. The flattened outer ends can have a roughened surface to further help reduce the amount of light reflected off the lead wires.

Abstract: A single-ended tungsten halogen lamp having a spherical or ellipsoidal envelope and an infrared reflective coating is manufactured using a mandrel alignment tool that radially centers an axially-oriented tungsten filament within the envelope. The manufacturing method includes forming the envelope in a glass tube. A filament assembly having an axially-oriented coiled tungsten filament is then placed into the interior of the envelope and the mandrel alignment tool is utilized to center the filament radially within the spherical or ellipsoidal envelope. The tool includes a tip that is inserted into the center of the tungsten coil to maintain the radial position of the filament during sealing of the glass tube around the filament assembly. After removing the tool, the glass tube is necked down and an inert halogen gas is placed within the envelope. The tube is then tipped off and the infrared reflective coating applied to form a completed bulb.

Abstract: A lamp assembly having a lamp base and an incandescent or electrodeless gas discharge light source mounted on the lamp base. The light source includes a light-transmissive envelope having a groove extending around the envelope at one end, and this groove is used to retain the envelope in place against a mounting surface of the lamp base. The mounting surface has a plurality of fingers circumferentially spaced about a central insertion axis of the light-transmissive envelope. When the envelope is inserted into the lamp base, the fingers deflect outwardly away from the insertion axis and then return at least partially to be received in the groove of the lamp envelope. The fingers provide a radially, inwardly directed force on the lamp envelope to inhibit relative movement between the envelope and the lamp base.

Abstract: An incandescent halogen lamp used in connection with a vehicle headlamp system in which stray light attributable to reflection off of internal lamp components is reduced while the structural integrity of the lamp is maintained. The halogen lamp includes two filaments, several lead wires, and a support bridge all sealed within a glass envelope. Each filament is connected at its outermost end to a flattened end portion of a lead wire which extends along the length of the filament from near the support bridge to the upper end of the filament. The flattened outer ends of the lead wires have a narrow profile that is in alignment with the direction of illumination of light from their respective filaments. This arrangement reduces the surface area that could otherwise interfere with light emitted by the filaments, and thereby reduces the overall stray light produced by the lamp. The flattened outer ends can have a roughened surface to further help reduce the amount of light reflected off the lead wires.

Abstract: A single-ended tungsten halogen lamp having a spherical or ellipsoidal envelope and an infrared reflective coating is manufactured using a mandrel alignment tool that radially centers an axially-oriented tungsten filament within the envelope. The manufacturing method includes forming the envelope in a glass tube. A filament assembly having an axially-oriented coiled tungsten filament is then placed into the interior of the envelope and the mandrel alignment tool is utilized to center the filament radially within the spherical or ellipsoidal envelope. The tool includes a tip that is inserted into the center of the tungsten coil to maintain the radial position of the filament during sealing of the glass tube around the filament assembly. After removing the tool, the glass tube is necked down and an inert halogen gas is placed within the envelope. The tube is then tipped off and the infrared reflective coating applied to form a completed bulb.