Nawata S, Takashima K
Research Institute for Scientific Measurements, Tohoku University, Sendai, Japan.
Appl Opt. 1966 Apr 1;5(4):609-13. doi: 10.1364/AO.5.000609.
A rapid, interferometric method for measuring the pitch of a nonrotating lead screw that involves no mechanical contact with the thread is described. The moving plane mirror of a Michelson interferometer is set on the axis of the lead screw. The lead screw is mounted on the carriage of a machine which moves it parallel to its axis. The Michelson fringes are counted continuously as the screw threads are moved across a light beam. The Michelson interferometer uses the green line of a (198)Hg isotope electrodeless lamp. The passage of a pitch point, to punctuate the fringe count, is sensed by photoelectric microscopes, and associated electronic circuitry, as described herein. The performance of the apparatus is presented.
