Abstract: Systems and methods are provided for measuring an ambient light level in a volume that is lighted by a pulsating light source. A first light sensor is configured to generate a first signal based on an amount of light detected in the volume. A bypass switch is configured to bypass the first light sensor at a first point in time when the light source is on and to not bypass the first light sensor at a second point in time when the light source is off. A second sensor is configured to generate a second signal based on an environment in the volume, and a difference circuit is configured to determine a difference magnitude between the second signal and the first signal to generate an ambient light signal.

Abstract: Systems and methods are provided for a transformerless power supply configured to limit heat generation. A system includes a power supply input configured to receive power from a time-varying input voltage source. A phase control circuit is configured to generate a current control signal, where the current control signal commands power to be drawn from the power supply through an output transistor, where the current control signal commands the drawn power to have a minimum current when the time-varying input voltage is at a maximum, and where the current control signal commands the drawn power to have a maximum current when the time-varying input voltage is at a minimum. A power supply output is responsive to the output transistor, where the power supply output is configured to output power drawn from the power supply input via the output transistor, wherein the outputted power is at a consistent power level.

Abstract: Systems and methods are provided for synchronizing a plurality of lighting devices. One or more potential-interference-neighbor (PIN) lighting devices are identified near a master lighting device. The master lighting device outputs a first lighting signal and the one or more PIN lighting devices output one or more second lighting signals. One or more time offsets between the first lighting signal and the one or more second lighting signals are determined. The one or more second lighting signals are adjusted based at least in part on the one or more time offsets to synchronize the first lighting signal and the one or more second lighting signals.

Abstract: System, methods, and apparatus, including devices and software, for providing self-adjusting light sources. In one aspect, a lighting unit includes one or more LEDs and an ambient light sensor. The light sensor measures ambient light in synchronization with intermittent off periods of light generated by the LEDs. For example, the LEDs in the lighting unit can be driven by a pulse width modulated signal that turns on and off the LEDs in an alternating manner, and the ambient light can be measured when the LEDs are turned off. In some implementations, a compact lighting unit, such as a light bulb, is provided that can be easily attached to standard light fixtures and can efficiently control its own brightness based on ambient light conditions.