An apparatus, system, and method for performing electron beam modulation includes an input pulser to provide an electromagnetic pulse; a radio frequency (RF) filter to filter the electromagnetic pulse; a nonlinear transmission line to receive the electromagnetic pulse, and generate a backward wave RF oscillation of a predetermined frequency to travel in a direction opposite that of the electromagnetic pulse; and an electron beam generating device including an anode and a cathode, the electron beam generating device to receive a combined electromagnetic pulse from the RF filter and the backward wave RF oscillation from the nonlinear transmission line to cause excitation of a modulated voltage between the anode and cathode, and to cause the electron beam generating device to emit an electron beam that is modulated at the predetermined frequency of the backward wave RF oscillation.

An apparatus for generating Smith-Purcell radiation having at least one spectral component at a wavelength A includes a periodic structure including a dielectric material and an electron source, in electromagnetic communication with the periodic structure, to emit an electron beam propagating within about 5 from a surface of the periodic structure to induce emission of the Smith-Purcell radiation. The electron beam has an electron energy tunable between about 0.5 keV and about 40 keV so as to change a wavelength of the Smith-Purcell radiation.

A radio-frequency (RF) generator is provided that produces a controlled overshoot. One embodiment includes a RF power amplifier and a direct-current (DC) power supply that includes a primary DC power supply, an auxiliary DC power supply, a half-bridge circuit, and a control circuit. The half-bridge circuit, in a first switching state, electrically connects, in series, the auxiliary DC power supply with the primary DC power supply and, in a second switching state, electrically disconnects the auxiliary DC power supply from the primary DC power supply. The control circuit places the half-bridge circuit in the first switching state for a first period of time and places the half-bridge circuit in the second switching state for a second period of time to produce a controlled overshoot in the power produced by the RF generator throughout the first period of time.

A replacement light tube for replacing a fluorescent light tube includes a bulb portion extending between a first end and a second end, the bulb portion comprising a support structure, a plurality of white light emitting diodes (LEDs) and an elongate light-transmissive cover. The support structure has a first surface extending between the first end and the second end. The plurality of LEDs are supported by the first surface and arranged between the first end and the second end. The elongate light-transmissive cover extends between the first end and the second end and over the first surface of the support structure. A first end cap and a second end cap are disposed on the first end and the second end, respectively, each configured to fit with a socket for a fluorescent light tube. A power supply circuit is configured to provide power to the plurality of LEDs. The plurality of LEDs are arranged to emit light through the elongate light-transmissive cover and at least a portion of the power supply circuit is packaged inside at least one of the end caps.

A lighting circuit includes a controllable electronic device in series with a power terminal of a controller, wherein operation of a switch causes the controller to maintain the electronic device conductive, whereby the controller then remains powered; and wherein the controller responds to a subsequent operation of the switch to render the electronic device nonconductive, whereby the controller is then unpowered even when electrical power is received. The lighting circuit is suitable for use, e.g., in a portable or other battery powered light.

Described herein are ambient lighting devices, methods, and systems that utilize at least one multimode artificial ambient light source, a control unit, and a remote image sensor. The control unit couples to at least one artificial ambient light source and is configured to output at least one control signal to the at least one artificial ambient light source. The at least one multimode artificial ambient light source is configured to output light of varying color and color temperature in response to said at least one control signal. The remote image sensor couples to the at least one control unit and is configured to detect at least one color and intensity characteristic and output an output signal to the at least one control unit, based on said color and intensity characteristic detected.

An electrical device can include a body having a shape and including one or more components, and first and second electrodes implemented at respective locations of the body and configured to provide first and second engagements with a mounting surface and to allow a settling motion when the electrical device is positioned on the mounting surface. The electrical device can further include a third electrode implemented at a respective location of the body and configured to allow a limited range of the settling motion such that at an end of the limited range of the settling motion, the third electrode provides a third engagement with the mounting surface.

An electrical device can include a body having a shape and including one or more components, and first and second electrodes implemented at respective locations of the body and configured to provide first and second engagements with a mounting surface and to allow a settling motion when the electrical device is positioned on the mounting surface. The electrical device can further include a third electrode implemented at a respective location of the body and configured to allow a limited range of the settling motion such that at an end of the limited range of the settling motion, the third electrode provides a third engagement with the mounting surface.

A high-safety LED tube, comprising: a first side having a first electrode and a second electrode; a second side having a third electrode and a fourth electrode; a first impedance module coupled to the first side; a second impedance module coupled to the second side; a first energy sensor having a first terminal coupled to the first impedance module; a second energy sensor having a first terminal coupled to the second impedance module; an LED unit coupled to the first impedance module and the second impedance module; a switch coupled to the LED unit; and a state control module coupled to the switch; wherein, when the first energy sensor or the second energy sensor detects an energy flowing between the first electrode and the second electrode or between the third electrode and the fourth electrode, the state control module turns on the switch.

An LED tube lamp includes a glass tube, two end caps, a power supply, and an LED light strip. The glass tube includes a main body region, two rear end regions, and two transition regions connecting the main body region and the rear end regions. The end cap is disposed at one end of the glass tube and the power supply is provided inside the end cap. The LED light strip is disposed inside the glass tube and has LED light sources disposed thereon. The LED light strip includes a bendable circuit sheet mounted on inner surface of the glass tube. The bendable circuit sheet of the LED light strip is formed with a freely extending end portion at one end, and the freely extending end portion is electrically connected to the power supply. The glass tube and the end cap are secured by a hot melt adhesive.