| CPC G01S 7/521 (2013.01) [G01N 29/34 (2013.01); G01S 15/931 (2013.01); H04R 1/08 (2013.01); H04R 17/02 (2013.01); H10N 30/30 (2023.02); H10N 30/87 (2023.02); G01S 2007/52009 (2013.01)] | 13 Claims |

|
1. An ultrasonic sensor comprising:
a first electrode that is provided in an ultrasonic microphone that includes a vibration element that provides a function for converting between mechanical vibrations and electrical signals;
a second electrode that is externally from the ultrasonic microphone such that an electrical characteristic between the second electrode and the first electrode changes based on an adhesion state of substances adhering to the ultrasonic microphone; and
a third electrode that is provided so as to suppress changes in the electrical characteristic between the first electrode and the second electrode caused by factors other than the adhesion of substances adhering to the ultrasonic microphone.
|