Light pipe technique for grid pulsing

Claim 1

In a coupling system having a first circuit which has an output signal which is to be coupled to an input of a second circuit the improvement comprising a light pipe connected between said first and second circuits for coupling said signal; light emitting means connected to the output signal of said first circuit so as to emit light in response to the output signal of said first circuit; said light emitting means being located at a first end of said light pipe so as to allow the light emitted to pass through said light pipe to a second end of said light pipe; detector means connected to the second end of said light pipe so as to detect said light and convert it to a signal; the output of said light detecting means being connected to an input of said second circuit; said first and second circuits have a high voltage potential difference between them; said light pipe provides insulation between the circuits; said first circuit is at ground potential; said second circuit is operating at a high voltage with respect to the ground potential; said light emitting means is a light emitting diode; and said detecting means is a photodetector diode; said output signal is an electrical pulse; circuit means connected to said light emitting diode so as to cause said light emitting diode to emit a short light pulse as compared to the length of the pulse of the output signal upon the occurrence of the leading edge of said output signal and a second light pulse upon the occurrence of the trailing edge of said output signal pulse; and said second circuit converting these two light pulses back into one long electrical pulse.