ACOUSTIC PULSE RECOGNITION LOCALIZING CONTACT PLATE AREA

摘要

A keypad with a plate and distinct keys that move relative to the plate to generate an acoustic signal for acoustic pulse recognition (APR). Each key represents an input value and is structured to contact the plate at a region smaller than an upper surface of the key where a fingre or a thumb comes into touch. The contact region of the plate coming into contact with an individual key is small relative the upper surface of the key, and hence, acoustic signals generated in response to the touch of the same key has less variance compared to acoustic signals generated in response to a direct touch of the plate by a finger or a thumb. As a result, the localization of the touch using APR can be more accurate compared to direct touch of the plate by a figure or a thumb.