Holography And Lasers Produce Super Precise Measurement

HOLOGRAPHY AND LASERS PRODUCE SUPER PRECISE MEASUREMENT by Anthony St E. Cardew* Advances in the application of opto-electronics such as laser techniques and holography have brought industrial measurement to new realms of precision and speed. The ability to have workshop systems with inherent accuracies of a half wavelength of light has opened up a whole new vista. Also, developments in holography have extended its application to, for instance, use in the quality control of critical parts and the location of defects. In the United Kingdom, a significant ad- vance in laser interferometer design has been the pioneering of a novel system by Michael Downs and Kenneth Rains of the National Physical Laboratory("), which was exploited by Linear Instru- ments(2) and forms the basis of its LIL 3000 series of laser interferometers. Lower cost Most laser interferometers use a sophis- ticated laser and electronic system to produce measurements and they are consequently very expensive. However...