RATIONAL-HARMONIC APPARATUS AND TECHNIQUE

A modulated cavity including a cavity; a modulation source; and a modulator located with said cavity and in electrical communication with said modulation source. The modulation source overdrives the modulator with a period of modulation T.sub.mod substantially equal to T.sub.roundtrip (n+(p/q)).sup.-1. n, p, and q are integers. T.sub.roundtrip is the period of a pulse making one round-trip in the cavity. In one embodiment of the invention p and q are relatively prime. In another embodiment of the invention the optical response of the modulator includes the qth harmonic of (1/T.sub.mod). In yet another embodiment of the invention p/q is an integer. In still yet another embodiment of the invention p/q is a rational number.