The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 14, 2025
Filed:
Jun. 27, 2024
Mitutoyo Corporation, Kanagawa, JP;
Tetsuro Kiriyama, Kanagawa, JP;
MITUTOYO CORPORATION, Kawasaki, JP;
Abstract
A correction value calculation method calculates correction values to correct the 2-phase sinusoidal signals (X, Y) output by the encoder, and includes: a polar coordinate calculation step for calculating, for N phase angles and the Lissajous radius corresponding to each phase angle in the Lissajous waveform drawn by the 2-phase sinusoidal signals, a squared radius, which is the square of the Lissajous radius corresponding to each phase angle; and a correction value calculation step for calculating, based on each phase angle and corresponding squared radius, at least a correction residual of an offset error of the signal X, a correction residual of an offset error of the signal Y, a correction residual of an amplitude ratio error of the signals X and Y, and a correction residual of a phase difference error between the signal X and the signal Y, and then calculating correction values based on the correction residuals.