Purespectrum, Inc.

Robert C Smallwood, Sr

Earl F Crandall

Ray J King

Robert G Crandall

A high frequency sinusoidal wave is generated and applied directly to a gas discharge lamp in a power efficient electronic ballast. Uniting a high frequency current fed oscillator with a transformer, where direct current may be applied to the center tap of the transformer primary winding to enable the impression of a sinusoidal alternating current at the secondary winding. This sinusoidal alternating current is applied directly to a gas discharge lamp. Feedback from the transformer controls the switching of the oscillator at resonant frequency.

High frequency electronic ballast with sine wave oscillator

A gas discharge lamp is driven with a constant current square wave from a current transformer where the number of volt-microseconds are designed such that at the start of each square wave, the voltage rises to the required ionization potential for the lamp, while the plasma has not yet started to conduct. As soon as the lamp ionizes the gas within the lamp and current flows, the voltage drops and current flows at the desired level. The current level is set to prevent the input of excessive power pulses into the lamp, to reduce the creation of infrared photons. In addition, the plasma is driven at this current level almost continuously (with reversing polarity), which does not allow the plasma time to cool down. Consequently, the lamp becomes a more efficient light emitter, thereby requiring less energy to achieve the same light output.

Method and system for driving a plasma-based light source

A high frequency sinusoidal wave is generated and applied directly to a gas discharge lamp in multiple phases in a power efficient electronic ballast. Uniting a high frequency current fed oscillator with a transformer, where direct current may be applied to the center tap of the transformer primary winding through an appropriately sized inductor to enable the impression of a sinusoidal alternating current at the secondary winding. This sinusoidal alternating current is applied directly to a gas discharge lamp. Feedback from the transformer controls the switching of the oscillator at resonant frequency.

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Englewood, CO, United States of America

Robert C Smallwood, Sr