A periodic grating is defined at the photoresist-coated wall of a circular cylinder with an integer number of particularly long grooves parallel to the generic lines by the holistic exposure of a radial phase mask to a normally incident collimated laser beam. The single-shot projected element corresponds to the inner grating of a high-resolution miniature shaft encoder.
Published in:
Photonics Journal, IEEE
(Volume:4
,
Issue:
4
)
Date of Publication: Aug. 2012