An electrically controlled variable reflectance mirror that includes a Pockels cell which enables its retardation or birefringence to be controlled in order to vary the light outcoupled from a laser cavity. Since the retardation is a function of the voltage applied to the Pockels cell, the voltage can be used to control the fraction of the output beam that is outcoupled from the laser cavity. The Pockels cell is formed with a constant reflectivity profile to form an electrically controlled uniform reflectivity electro-optic mirror. In an alternate embodiment of the invention, the Pockels cell is configured with spatially varying retardation to form an electrically controlled graded reflectivity electro-optic mirror. Both embodiments of the invention enable a lasing system, such as a solid state lasing system, to be operated over a relatively wide range of operating parameters utilizing a single set of optics.