Methods and systems for producing a change in a medium. A first method and system (1) place in a vicinity of the medium at least one upconverter including a gas for plasma ignition, with the upconverter being configured, upon exposure to initiation energy, to generate light for emission into the medium, and (2) apply the initiation energy from an energy source including the first wavelength λ.sub.1 to the medium, wherein the emitted light directly or indirectly produces the change in the medium. A second method and system (1) place in a vicinity of the medium an agent receptive to microwave radiation or radiofrequency radiation, and (2) apply as an initiation energy the microwave radiation or radiofrequency radiation by which the agent directly or indirectly generates emitted light in the infrared, visible, or ultraviolet range to produce at least one of physical and biological changes in the medium.

An emergency output circuit for starting LED lamp tubes with leakage protection comprises a PWM pulse generator provided with a PWM chip. When a control terminal detects a power outage, a high level is instantly output to the PWM chip, and the PWM pulse generator outputs complementary drive PWM rectangular waves with a controllable dead time, which are boosted and filtered into a 250V DC voltage; then, positive and negative alternating square waves are formed through a full-bridge inverter circuit, and two pairs of MOS transistors are turned on alternately through complementary PWM control to generate an AC voltage UAB on an LED lamp tube; and finally, an AC rectangular wave slowly changing into a stable 135V AC output from a 250V DC output is obtained through a correction circuit to replace existing methods to turn on the LED tube, thus effectively simplifying the circuit.

A sanitization apparatus includes an excimer lamp and a power converter. The power converter comprises a wide band gap device and a planar inductor. The wide band gap device is selectively switchable between a first mode wherein the inductor is electrically charged and a second mode wherein the inductor is electrically discharged. The wide band gap may be repeatedly switched between the first and second modes to generate a nano second pulse output voltage waveform.

A sanitization apparatus includes an excimer lamp, a power converter configured to power the excimer lamp and a controller. The controller is configured to monitor an impedance of the excimer lamp and vary an output voltage waveform of the power converter based upon the impedance.

An RF fluorescent lamp, comprising a bulbous vitreous portion of the RF fluorescent lamp comprising a vitreous envelope filled with a working gas mixture, a power coupler to induce an alternating electric field within the vitreous envelope, an electronic ballast, and a mercury amalgam accommodating structure mounted within the lamp envelope and adapted to absorb power from the electric field to rapidly heat and vaporize an amalgam of mercury to rapidly illuminate the lamp envelope during a turn-on phase of the RF fluorescent lamp, wherein the structure is comprised of a substrate material coated with a mixture of indium and gold.

In electrodeless HID lamps the radio frequency (RF) source is separated from a lamp housing in which vessel containing plasma arc is mounted. This lamp housing is usually designed to maximize the amount of RF energy incident on the plasma arc. The plasma arc, however, cannot convert the entire amount of incident RF energy into light and a portion instead is released as propagating radiation or remains localized RF electromagnetic fields in the vicinity of lamp. In this invention, we introduce field suppression probes: Small, configurable structures that are made of conductive materials that mount directly to the lamp housing or alternately the lamp fixture that is able to suppress unused RF energy that is emanated from the lamp housing or plasma. These probes, when configured with the lamp, can substantially suppress the unused RF energy and prevent EMI emissions and reduce RF feedback that can adversely affect the lamp.

Electrodeless high intensity discharge lamps have the promise of higher reliability and higher efficiency than traditional electroded high intensity discharge lamps. However most electrodeless HIDs operate in the frequency range of around 400 MHz to 2.5 GHz resulting in expensive, inefficient RF drivers that reduce the overall efficacy of the lamp. Operating the lamp at lower frequencies results in substantial increase in the size of the resonators used in traditional electrodeless HIDs. In this invention a novel design is used to lower the operating frequency of the resonator without increasing the size of the resonator. This provides an avenue to increase the conversion efficiency of the RF driver and the efficacy of the lamp system.

A novel compact air-cavity electrodeless high intensity discharge lamp is disclosed that provides added flexibility in its design to improve performance and reliability. A coupling sleeve surrounds a bulb assembly that can replace the output coupling element require for effective operation of the lamp. The coupling sleeve couples the RF energy from the input coupling element to the bulb and the bulb assembly serves to provide the heat sinking needed for the bulb to operate within the temperature range necessary to achieve optimum performance with good reliability. Changing the design of the bulb assembly does not impact the resonant frequency of the air-cavity resonator. De-coupling the bulb assembly design from the operating frequency of the resonator gives more flexibility to designer to optimize the overall performance of the electrodeless HID lamp.

Methods and systems for producing a change in a medium. A first method and system (1) place in a vicinity of the medium at least one upconverter including a gas for plasma ignition, with the upconverter being configured, upon exposure to initiation energy, to generate light for emission into the medium, and (2) apply the initiation energy from an energy source including the first wavelength λ.sub.1 to the medium, wherein the emitted light directly or indirectly produces the change in the medium. A second method and system (1) place in a vicinity of the medium an agent receptive to microwave radiation or radiofrequency radiation, and (2) apply as an initiation energy the microwave radiation or radiofrequency radiation by which the agent directly or indirectly generates emitted light in the infrared, visible, or ultraviolet range to produce at least one of physical and biological changes in the medium.

Provided is a new light source device using an excimer lamp, particularly, a light source device for sterilization and deodorization. The light source device includes an excimer lamp and a flyback-type lighting device that supplies power to the excimer lamp. The lighting device includes a transformer, a switching element, and a control circuit that supplies a drive signal to the switching element. The control circuit controls the switching element on and off so that the switching frequency (FS) for the switching element at the time of starting to light is lower than the switching frequency (FO) at the time of steady-state lighting, and the ON-duty (TS) for the switching element at the time of starting to light is lower than the ON-duty (TO) at the time of steady-state lighting.