The carriage of a ruling engine is driven by a hydraulic system servo-controlled by an optical interferometer, so that the position of the carriage is determined in terms of the wavelength of light. The arrangement is free from the errors of the conventional lead-screw system and is far cheaper to construct.
© 1965 Optical Society of America
Original Manuscript: July 27, 1964
Published: February 1, 1965
W. R. Horsfield, "Ruling Engine with Hydraulic Drive," Appl. Opt. 4, 189-193 (1965)