US 12,093,491 B2
Operation detection device
Tomoya Sasaki, Miyagi (JP); and Shotaro Asakura, Miyagi (JP)
Assigned to ALPS ALPINE CO., LTD., Tokyo (JP)
Filed by ALPS ALPINE CO., LTD., Tokyo (JP)
Filed on Sep. 6, 2023, as Appl. No. 18/461,800.
Application 18/461,800 is a continuation of application No. PCT/JP2022/007784, filed on Feb. 25, 2022.
Claims priority of application No. 2021-063104 (JP), filed on Apr. 1, 2021.
Prior Publication US 2023/0418420 A1, Dec. 28, 2023
Int. Cl. G06F 3/041 (2006.01); G06F 3/044 (2006.01)
CPC G06F 3/044 (2013.01) 7 Claims
OG exemplary drawing
 
1. An operation detection device, comprising:
an electrostatic sensor;
a drive circuit configured to output a drive signal to the electrostatic sensor in order to detect an operator's operation on the electrostatic sensor; and
a control unit configured to determine presence or absence of the operation based on an output value of the electrostatic sensor, and control a drive waveform of the drive signal,
wherein the control unit controls the drive waveform according to a cycle that is a predetermined period of time including both a detection period in which detection of the operation is performed and a non-detection period in which detection of the operation is not performed,
the drive waveform has a shape that is based on a periodic function that repeats a constant pattern for an entirety of the cycle, and
the control unit changes a phase of the drive signal in the detection period by controlling a property of the drive waveform in the non-detection period.