Refreshing method of background signal and device for applying the method

A sensing device, comprising:

• a first sensing layer and a second sensing layer arranged in a stacked configuration, a sensing area defined jointly by the first and second sensing layers, a plurality of position coordinates being defined within the sensing area;
• and
• a sensing controller capable of activating and detecting the sensing area, obtaining positional information, obtaining a refreshing area based on the positional information and a measuring breadth, and refreshing a background signal of the refreshing area,
• wherein
• the sensing controller is configured to obtain the positional information based on a determination that a threshold value with respect to a first background signal value is breached, wherein the first background signal value corresponds to a first position coordinate of the plurality of position coordinates,
• the refreshing area comprises at least one of the first position coordinate of the plurality of position coordinates or the first position coordinate of the plurality of position coordinates and one or more other position coordinates of the plurality of position coordinates,
• the first background signal value is stored in a memory associated with the sensing device;
• one or more other background signal values corresponding to the one or more other position coordinates of the plurality of position coordinates are stored in the memory, and
• the sensing controller is configured to refresh the background signal by updating only the background signal values corresponding to the position coordinates included in the refreshing area.