New methods to obtain higher power from the laser with the unstable resonator

New methods to obtain higher power from the laser with the unstable resonator are proposed. Calculations are performed for expanding radius of concave or convex mirror to reduce the diffraction loss power from the concave mirror and to convert the power spread out from it into the output power. The Fresnel-Kirchhoff formula is used for the iterative computer calculation in the passive resonator and for a carbon-dioxide laser. The calculations show that the increase of the output power can be obtained more than 20 percent with expanding concave mirror in the carbon-dioxide laser.