Using a small acoustic microphone in the device, vibrations caused by a user scratching or tapping on a tabletop are detected and used as input signals.
The invention discloses a detecting device, a detecting method and a tapping system using the same, wherein the detecting device contains an image obtaining module and a detecting module.
To this end, a rotating scraper blade and a tapping and shaking device have been designed and bring about good results in its actual use in production.