Patent ID: 8725436

Claim:
A motion state detecting method using a detector which detects one of a conducting state and a non-conducting state according to a movement of an object, the method comprising: first processing, using the detector to measure either a first number of state changes that is the number of times of change from the conducting state to the non-conducting state per unit measurement time interval or a second number of state changes that is the number of times of change from the non-conducting state to the conducting state per the unit measurement time interval; and second processing, using the detector to regard either the first number of state changes or the second number of state changes as a change determination value, and to adjust the duration of the unit measurement time interval based on the change determination value; wherein a proportion of time of the conducting state per the adjusted unit measurement time interval or a proportion of time of the non-conducting state per the adjusted unit measurement time interval represents the motion state being detected.