NONDIFFRACTING BEAM FROM A SPATIALLY FILTERED FABRY-PEROT RESONATOR

An experiment was performed in which a single ring from a Fabry-Perot transmission fringe pattern was used to create a nondiffracting beam. The transverse and axial intensity distributions of this beam were measured and found to be in good agreement with previously existing and newly derived theoretical expressions. The diffraction-free range was found from calculation to be proportional to the cavity finesse and length, and the central-spot radius of the beam was theoretically shown to be proportional to the square root of the wavelength and cavity length.