| 摘要 |
A high intensity discharge light source that uses a pseudo-random sequence generator to modulate an RF drive signal, and reduce electromagnetic interference (EMI) produced by the light source. The light source includes a high intensity RF discharge lamp, control and RF drive electronics that are coupled between a power source and the lamp. The control and drive electronics include an electromagnetic interference filter, and a regulator that outputs a bias voltage. The drive electronics provide RF power to the lamp, and includes an oscillator, a mixer/modulator, an amplifier, and an impedance matching network. The control circuit includes a pseudo-random sequence generator that generates a pseudo-random sequence of pulses to modulate the mixer/modulator and thus the output of the oscillator to thereby reduce the EMI spectral density generated in driving the RF discharge lamp.
|
