The switching and controlling of laser oscillation by optical injection or radiative-coupling schemes using the two laser system are investigated theoretically and experimentally in this paper. The output from aQ-switched laser was injected into the second laser to effect optical coupling. Corresponding to this model, we have succeeded in deriving a general analytical expression for the functional dependance of the quenching time interval on the parameters of the radiation-coupled lasers. The experimental results obtained using two ruby lasers compare quite favorably with the theoretical analysis. Finally, the preliminary observation of self-control or automodulation of laser oscillation due to optically induced ultrasonic vibration of the ruby rod through the optical coupling with the single laser pulse is mentioned briefly.