Abbe error correction system and method
CA 2396259 A1 · Owner: Electro Scientific Industries, Inc. · Inventors: Cutler, Donald R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention preferably employs non-contact small-displacement, capacitive sensors (124 128, 130, 131, 132) to determine Abbe errors due to the pitch (20), yaw (22), or roll (18) of a near linear mechanical stage (56 58) that are not indicated by an on-axis position indicator such as a linear , scale encoder or laser interferometer. The system is calibrated against a precise reference standard so the corrections depend only on sensing small changes in the sensor readings and not on absolute accuracy of the sensor readings. Although the present invention is preferred for use in split-axis positioning systems (50) with inertially separated stages (56 58), the , invention can be …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed January 5, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 5, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 5, 2023.
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Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.