Frequency stabilized optical maser

Claim 1

IN COMBINATION, AN OPTICAL MASER COMPRISING MEANS FORMING AN OPTICAL CAVITY RESONATOR CHARACTERIZED BY A PLURALITY OF RESONANT MODES AT DISTINCT OPTICAL FREQUENCIES, AN ACTIVE MASER MEDIUM DISPOSED WITHIN SAID CAVITY RESONATOR, SAID MEDIUM BEING CHARACTERIZED BY AN INHOMOGENEOUSLY BROADENED OPTICAL EMISSION LINE HAVING A WIDTH WHICH ENCOMPASSES THE FREQUENCIES OF A PLURALITY OF SAID RESONANT MODES, PUMP MEANS FOR CAUSING SAID MASER TO OSCILLATE SIMULTANEOUSLY IN AT LEAST THREE OF SAID MODES, THE OSCILLATION FREQUENCIES OF SAID MODES BEING SHIFTED TOWARD THE CENTER OF SAID EMISSION LINE, THE AMOUNT OF SAID SHIFT VARYING WITH THE SEPARATION OF THE MODE FREQUENCIES FROM THE LINE CENTER SO THAT THE SEPARATION OF ADJACENT OSCILLATION FREQUENCIES IS LEAST NEAR THE LINE CENTER AND INCREASES AWAY FROM THE LINE CENTER, MEANS FOR DETECTING BEATS BETWEEN PAIRS OF OSCILLATING MODES IN SAID OPTICAL MASER, AND MEANS RESPONSIVE TO THE MAGNITUDE OF THE FREQUENCY DIFFERENCE BETWEEN SELECTED PAIRS OF SAID BEATS FOR TUNING SAID OPTICAL MASER.