PLANE-WAVE THEORY OF A MICHELSON LASER COUPLER WITH A DIELECTRIC SLABBEAM SPLITTER

The plane-wave theory for the transmittance and absorbtance of a perfe ctly aligned Michelson coupler with a dielectric slab beam splitter is presented. It is shown that the transmittance and absorbtance vary si nusoidally and in quadrature. As a result of this quadrature relations hip, the maximum transmittance occurs at a setting of the translatable coupler mirror at which the absorbtance is not at an extremum, and so the curve of output power as a function of coupler setting is asymmet rical with respect to the setting yielding maximum transmittance. Expe rimental measurements of the output power of a far-infrared HCN laser as a function of the coupler setting confirm this asymmetry, which see ms to have been overlooked or ignored in previous studies. (C) 1996 Op tical Society of America