Mode Selection in Resonators With Bi-Lens Mirror

Modifications of laser resonators enable the intracavity generation of beams with singularities suitable for a novel approach to high resolution microscopy. The characteristics of a resonator with a bi-lens mirror replacing one laser mirror are investigated in this paper. It is shown that the highest selectivity of an oscillating mode with a linear singularity can be achieved with convex bi-lens reflectors while fairly good selectivity is still possible with concave mirror possessing minimum diffraction losses.