Ruling engine using a piezoelectric device for large and high-groove density gratings

A ruling engine for large and/or high-groove density gratings is developed. A hybrid driving method that uses a piezoelectric device and a screw-nut mechanism is adopted to achieve stop-and-go blank motion with a closed-loop control system. Several test gratings, including a ruled area of 300(width) x 200(groove length) sq mm, groove densities of 6000 and 10,000 grooves/mm, and a uniform and varied-line space, are ruled to confirm the basic functions of the ruling engine. A set of four spherical, varied-line-space gratings with central groove densities of 6000, 4550, 3450, and 2616 grooves/mm and a ruled area of 200 x 200 sq mm is ruled for the orbital retrievable far and extreme ultraviolet spectrometer.