Patent ID: 11904367
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Chemical engineering (Chemistry)
Classification: CPC B  G | IPC B  G

Claim 7:
8. A cleaning method for cleaning a surface of a light-transmissive body having water repellency by a cleaning apparatus that includes a holder to hold an imaging element, the light-transmissive body in a field of view of the imaging element, a vibrator to vibrate the light-transmissive body, a driver to drive the vibrator, a discharger to discharge a cleaner onto the surface of the light-transmissive body, and a controller to control the driver and the discharger, the cleaning method comprising:
causing the discharger to discharge the cleaner;
controlling the driver such that the light-transmissive body is vibrated at a resonant frequency for a predetermined period after the cleaner is caused to be discharged in order to make the surface of the light-transmissive body pseudo-hydrophilic; and
controlling the driver such that, after the predetermined period, vibration of the light-transmissive body is stopped or the light-transmissive body is vibrated at a frequency other than the resonant frequency in order to return the surface of the light-transmissive body to a state of water repellency; wherein
the cleaning apparatus includes a detector to detect a value related to an impedance of the vibrator driven by the driver; and
the controller performs tracking control such that the light-transmissive body is vibrated at the resonant frequency between a first resonant frequency and a second resonant frequency based on the value related to the impedance detected by the detector.