Selected two-color operation of a CO2laser

Two-color length measurement schemes have recently been proposed which require a multiwavelength laser source having means of laser frequency stabilization. A simple CO
2
laser can be adjusted and operated such that these requirements may be addressed. It is shown that through certain simple incremental length adjustments a specified two-color pair may be obtained. Other colors may be caused to appear in selectable sequence through further adjustment. An experimental laser is described in which these characteristics have been observed.