A system for obtaining a multispectral image of a scene includes a first light source, a second light source, at least one imaging sensor, and a controller. The first light source emits light in a first wavelength range. The second light source emits light in a second wavelength range. The at least one imaging sensor senses light in the first wavelength range reflected off of the scene during a first illumination sensing period and senses light in the second wavelength range reflected off of the scene during a second illumination sensing period. The controller is electrically coupled to the at least one imaging sensor. The controller interprets signals received from the at least one imaging sensor as imaging data, stores the imaging data, and analyzes the imaging data with regard to multiple dimensions. The first illumination sensing period and the second illumination sensing period are discrete time periods.

A power adjusting circuit, an LED power supply and an LED luminaire. The power adjusting circuit includes: a zero-crossing detecting unit, adapted to generate a zero-crossing detection signal according to an high-frequency signal, wherein the zero-crossing detection signal is a pulse wave or a square wave, and the high-frequency signal is a sine wave or an AC wave; a signal processing unit, adapted to determine a second number of pulses or square waves of the zero-crossing detection signal corresponding to an adjustment signal that is input externally, according to a first number of pulses or square waves of the zero-crossing detection signal corresponding to a full-load operation of a functional device; a counting unit, adapted to generate a switch control signal according to the first number and the second number; and a switch unit, adapted to control an output of the high-frequency signal according to the switch control signal.

A power adjusting circuit, an LED power supply and an LED luminaire. The power adjusting circuit includes: a zero-crossing detecting unit, adapted to generate a zero-crossing detection signal according to an high-frequency signal, wherein the zero-crossing detection signal is a pulse wave or a square wave, and the high-frequency signal is a sine wave or an AC wave; a signal processing unit, adapted to determine a second number of pulses or square waves of the zero-crossing detection signal corresponding to an adjustment signal that is input externally, according to a first number of pulses or square waves of the zero-crossing detection signal corresponding to a full-load operation of a functional device; a counting unit, adapted to generate a switch control signal according to the first number and the second number; and a switch unit, adapted to control an output of the high-frequency signal according to the switch control signal.

A circuit for driving a light-emitting diode (LED) load and a direct current to direct current (DC-DC) converter includes a first sampling sub-circuit, a driving circuit. The first sampling sub-circuit is configured to generate a current signal representing a load current of the LED load. The driving circuit is configured to receive a brightness adjustment signal and a frequency adjustment signal; generate a first control signal, based on the current signal and the brightness adjustment signal, for controlling an output current of the DC-DC converter; and generate a second control signal, based on the frequency adjustment signal, for controlling a switching frequency of the LED load.

A power module includes a power converter having a controller configured to control the power converter. The controller is configured to control the power converter using feedback for a first load on the power converter, and to allow the power converter to operate without controlling the power converter using the feedback for second load on the power converter higher than the first load.

A power module includes a power converter having a controller configured to control the power converter. The controller is configured to control the power converter using feedback for a first load on the power converter, and to allow the power converter to operate without controlling the power converter using the feedback for second load on the power converter higher than the first load.

A load control device for controlling the intensity of a lighting load, such as a light-emitting diode (LED) light source, may include a power converter circuit operable to receive a rectified AC voltage and to generate a DC bus voltage, a load regulation circuit operable to receive the bus voltage and to control the magnitude of a load current conducted through the lighting load, and a control circuit operatively coupled to the load regulation circuit for pulse width modulating or pulse frequency modulating the load current to control the intensity of the lighting load to a target intensity. The control circuit may control the intensity of the lighting load by pulse width modulating the load current when the target intensity is above a predetermined threshold and control the intensity of the lighting load by pulse frequency modulating the load current when the target intensity is below the predetermined threshold.

A load control device for controlling the intensity of a lighting load, such as a light-emitting diode (LED) light source, may include a power converter circuit operable to receive a rectified AC voltage and to generate a DC bus voltage, a load regulation circuit operable to receive the bus voltage and to control the magnitude of a load current conducted through the lighting load, and a control circuit operatively coupled to the load regulation circuit for pulse width modulating or pulse frequency modulating the load current to control the intensity of the lighting load to a target intensity. The control circuit may control the intensity of the lighting load by pulse width modulating the load current when the target intensity is above a predetermined threshold and control the intensity of the lighting load by pulse frequency modulating the load current when the target intensity is below the predetermined threshold.

Electric light sources typically exhibit temporal variations in luminous flux output, commonly referred to as “flicker.” Flicker, or temporal modulation, is known to influence the growth, health and behavior patterns of humans, and is also linked to growth, health and behavior patterns throughout the growth cycle of plants and animals. Control of peak radiant flux emitted by a light source to temporally modulate a light source will allow for the control of plants and animals for sustainable farming including but not limited to horticultural, agricultural, or aquacultural endeavors. The light source allows the transmission of daylight, which is combined with the flicker.

Electric light sources typically exhibit temporal variations in luminous flux output, commonly referred to as “flicker.” Flicker, or temporal modulation, is known to influence the growth, health and behavior patterns of humans, and is also linked to growth, health and behavior patterns throughout the growth cycle of plants and animals. Control of peak radiant flux emitted by a light source to temporally modulate a light source will allow for the control of plants and animals for sustainable farming including but not limited to horticultural, agricultural, or aquacultural endeavors. The light source allows the transmission of daylight, which is combined with the flicker.