Patent ID: 11892377
Assignee: SEIKO EPSON CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 3:
4. The time point acquisition method according to claim 1, wherein
the vibration component is removed by performing low-pass filter processing on the time-series data,
high-pass filter processing is performed on the time-series data on which the low-pass filter processing was performed,
a first peak and a second peak of the time-series data on which the high-pass filter processing was performed are acquired, and a first interval before the first peak, a second interval between the first peak and the second peak, and a third interval after the second peak are acquired,
in the first interval, a correction curve of the first interval is acquired by inverting a sign of the time-series data on which the high-pass filter processing was performed,
in an interval less than a product of a first coefficient and a value obtained by inverting a sign of an amplitude of the first peak, a first straight line which is an approximate straight line of a correction curve of the first interval is acquired,
in the third interval, a correction curve of the third interval is acquired by inverting a sign of the time-series data on which the high-pass filter processing was performed,
in an interval less than a product of a third coefficient and a value obtained by inverting a sign of an amplitude of the second peak, a third straight line which is an approximate straight line of a correction curve of the third interval is acquired,
a time point within a period after one time point and before another time point of two time points corresponding to two consecutive pieces of data between which a predetermined threshold is present is acquired as the entry time point, the two consecutive pieces of data being included in a sum of the time-series data on which the high-pass filter processing was performed and the first straight line, and
a time point within a period after one time point and before the other time point of two time points corresponding to two consecutive pieces of data between which a predetermined threshold is present is acquired as the exit time point, the two consecutive pieces of data being included in a sum of the time-series data on which the high-pass filter processing was performed and the third straight line.