Abstract: Apparatus for both rotating and translating a scanning mirror is provided. The mirror is carried by a hollow shaft which is rotated by air under pressure. Such air is fed into the hollow cavity in the shaft and escapes through a turbine which is a part of the shaft. The turbine rotates the shaft. The shaft is supported by air bearings from a surrounding housing. That housing is supported by a slide which is pneumatically supported from a stationary rail. The slide is translated parallel to the axis of the shaft by a lead screw driven by a stepping motor. The lead screw cooperates with a lead screw nut which is affixed to said slide. The aforesaid arrangement provides great accuracy and minimum instability during the scanning operation.