Q-switching laser system having electronically controlled output coupling

Abstract

Abstract A LASER ROD IS OPTICALLY ALIGNED WITH A PAIR OF TOTALLY REFLECTING MIRRORS FORMING AN OPTICAL RESONANT CAVITY. BEAM SPLITTING POLARIZER AND AN ELECTRO-OPTICAL Q-SWITCHING CELL ARE DISPOSED ALONG THE OPTICAL AXIS OF THE CAVITY BETWEEN THE ROD AND ONE MIRROR. THE BEAM SPLITTING POLAR LIZER DIRECTS A PORTION OF THE ENERGY IN THE LASER RESONATOR OUT OF THE CAVITY. THE PORTION OF THE ENERGY WHICH EXTRACTED IS DEPENDENT UPON THE INDUCED BIREFRINGENCE OF THE ELECTRO-OPTICAL Q-SWITCHING CELL, THE LATTER BEING SELECTIVELY CONTROLLED IN ACCORDANCE WITH A VOLTAGE APPLIED TO THE CELL. THE CELL FUNCTIONS TO ALTER THE LINEARLY POLARIZED LIGHT BEAM EMITTED BY THE LASER TO AN ELLIPTICALLY POLARIZED BEAM, THE ORTHOGONAL COMPONENT OF WHICH IS COUPLED FROM THE RESONATOR BY THE POLARIZER. IN A HOLD-OFF MODE, THE LASER ROD IS PUMPED BU HE Q-SWITCHING CELL IS ACTIVATED TO CAUSE THE POLARIZER TO COUPLE SPONTANEOSLY EMMITED RADIATION FROM THE CAVITY, PREVENTING OSCILLATION. IN THE PULSE MODE, THE Q-SWITCHING CELL IS ACTIVATED TO EFFECT FEEDBACK BY THE POLARIZER OF SUFFICIENT ENERGY TO THE LASER ROD TO CAUSE OSCILLATIONS WITH A PORTION OF THE OSCILLATING ENERGY COUPLED OUT OF THE CAVITY BY THE POLARIZER. BY ELECTRONIC TUNING OF THE Q-SWITCHING CELL, OPTIMUM OUTPUT COUPLING CONDITIONS ARE OBTAINED.

Inventors

• 👤 J Wentz

Bibliographic Details