Avoidance and elimination of errors in optical scanning

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

For the testing of flats, spheres or aspheres, the optical scanning technique has become a competitor to interferometric techniques. The set-up implemented at PTB for the ultra- precise optical scanning of optical flats will be presented and the underlying principles explained, with a special view to the avoidance of error influences in the optical set-up and to the elimination of the remaining errors. The basic principle of the scanning set-up is that an autocollimation telescope combined with a movable pentagon prism is used to register the surface slope angles. To avoid higher-order errors originating in the pentagon prism, its angular position is kept constant in space by active stabilization. Another advantageous principle is that difference measurements for slopes are performed. This has become possible thanks to a new error-free difference method recently developed by PTB. The combination of these principles eliminates, theoretically, the influences of all possible errors of the scanning facility. An experiment using a high-quality flat ((lambda) /60) 140 mm in diameter showed a reproducibility of 0,2 nm over one week.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Avoidance and elimination of errors in optical scanning does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Avoidance and elimination of errors in optical scanning, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Avoidance and elimination of errors in optical scanning will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-990254

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.