Fizeau toothed wheel
Fizeau toothed wheel
[fē′zō ¦tütht ′wēl] (optics)
Rapidly rotating toothed wheel which was used to measure the speed of light by adjusting the rotation speed until light passing through one tooth opening and reflected from a distant mirror would pass through the next tooth opening on return.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.