FIELD: optical instrumentation engineering; applicable in optico-mechanical and chemical industries and in laser engineering. SUBSTANCE: method includes joint of several parts by optical contact and subsequent heat treatment. Parts are joined through intermediate member which is joined with one of parts machined to thickness-member external size ratio of 1/100-1/200 and joined with next part. EFFECT: reduced linear losses of energy of laser radiation in passage through layer of working fluid in cell, improved safety and prolonged service life of cell.
