CPC G06F 3/03543 (2013.01) [G06F 3/0317 (2013.01); G06F 3/0383 (2013.01)] | 10 Claims |
1. An optical navigation device, comprising:
an optical sensor, configured to sense optical data; and
a processing circuit, configured to compute motions of the optical navigation device based on the optical data, and configured to output the motions, wherein a first CPI is set to the processing circuit;
wherein the processing circuit receives a calibration command to calibrate the first CPI to a second CPI, wherein the second CPI is computed via following steps:
(a) computing a real CPI corresponding to times of motions output by the processing circuit during a time interval that a relative displacement between the optical navigation device and a surface reaches a first predetermined distance;
(b) computing a ratio between the real CPI and the first CPI or a difference between the real CPI and the first CPI; and
(c)generating the second CPI based on the ratio or the difference;
wherein the step (a) further comprises:
providing a calibration ruler pattern, wherein the calibration ruler comprises a plurality of mark regions;
determining the relative displacement according to the mark regions.
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