Abstract: An LED track-lighting system includes an LED for emitting light. A light-transmitting element captures light emitted by the LED light and emits it over at least a portion of the track.

Abstract: LEDs that provide street illumination are used to create emergency signals. This facilitates simple retrofitting of existing streetlighting infrastructure. In one embodiment, a streetlight comprises an LED set that itself comprises or consists of a plurality of LEDs collectively producing a white light output. The streetlight also includes a receiver for receiving a signal of an alarm condition, and a controller for (i) disabling the LED set during a daylight period, (ii) maintaining the normal operating mode during a lighting period distinct from the daylight period, and (iii) in response to the alarm condition detected by the receiver, de-activating at least one of the LEDs to produce a non-white (e.g., red or amber) output signaling the alarm condition.

Abstract: Power consumed by an LED driver may be reduced by drawing, from an electronic transformer or dimmer, an input current that is constant over a plurality of input voltages. Power derived from the constant input current is provided to the LED driver.

Abstract: A voltage level supplied to power a plurality of LED light fixtures is dynamically adjusted to control the headroom of the voltage level. The current drawn by at least one of the plurality of LED light fixtures is monitored, and the voltage is increased from zero until the monitored current reaches its maximum.

Abstract: In various embodiments, a startup circuit for a low-voltage-lighting electronic transformer includes a low-impedance output circuit. At the beginning of an AC signal cycle, the low-impedance output circuit presents a low-impedance path to the output of the transformer, thereby causing a surge of current in the transformer and initiating oscillation therein.

Abstract: A thermal-foldback system detects an over-temperature condition in an LED lamp. In response to the over-temperature condition, the thermal-foldback system chops a portion of the input power waveform drawn by the LED lamp.

Abstract: A brightness controller determines a lowest dimmer setpoint and an average power to a light source at the lowest dimmer setpoint. An average power supplied to the light source is set based on a setting of the dimmer relative to the average power at the lowest dimmer setpoint.

Abstract: A system for protecting a heat-sensitive component in an LED lamp from overheating. The system including: a heat-generating component, a heat-dissipating component thermally coupled to the heat-generating component, a heat-sensitive component electrically connected to the heat-generating component, and a heat-isolating element for thermally isolating the heat-generating component and the heat-sensitive component.

Abstract: The type of an LED power driver (i.e., a magnetic transformer or an electronic transformer) is determined by manipulating the AC voltage produced by the power driver so that it may be analyzed and the type of power driver reliably determined. In various embodiments, a system for detecting an AC power supply type includes a circuit for monitoring a negative half or a positive half of an output voltage of the AC power supply and an analyzer for determining the AC power supply type based at least in part on a presence or absence of an envelope in the monitored output voltage.

Abstract: A permanent adapter for incandescent lighting fixtures can removably receive LEDs but cannot itself be removed from the fixture.

Abstract: LEDs that provide street illumination are used to create emergency signals. This facilitates simple retrofitting of existing streetlighting infrastructure. In one embodiment, a streetlight comprises an LED set that itself comprises or consists of a plurality of LEDs collectively producing a white light output. The streetlight also includes a receiver for receiving a signal of an alarm condition, and a controller for (i) disabling the LED set during a daylight period, (ii) maintaining the normal operating mode during a lighting period distinct from the daylight period, and (iii) in response to the alarm condition detected by the receiver, de-activating at least one of the LEDs to produce a non-white (e.g.

Abstract: Lights for attachment to a vehicle including a first illuminating means directed substantially perpendicular to a surface plane of the light and a second illuminating means directed substantially parallel with the surface plane of the light. The second illuminating means may be mounted solely within a lower hemisphere of the light. The light may also include a covering hood.

Abstract: There is provided a new and useful alarm system for use on a school bus that ensures that drivers walk through the inside of a vehicle prior to exiting. Once the vehicle ignition system has been in the on position for a specified period of time, or the vehicle has traveled at or above a pre-determined speed, the system will enter a set state. The system may also feature means for turning on the interior lights of the vehicle to aid the driver during their visual sweep of the vehicle. The system may also feature means for dis-engaging deactivation means at the rear of the vehicle if it is in the alarm state.