Thickness detection device, method and system

A thickness detection method using a detection device for detection, comprising:

• applying a detection voltage to a common unit;
• placing an object to be detected in a gap between the common unit and a detection unit, controlling the object to be detected to move, wherein a moving direction of the object to be detected is perpendicular to a second direction, and obtaining a plurality of first voltage signals;
• acquiring a plurality of correction parameters, wherein the correction parameters are in one-to-one correspondence with the first voltage signals;
• correcting the corresponding first voltage signals according to the correction parameters to obtain a plurality of corrected voltage signals;
• and
• calculating a thickness of the object to be detected according to the corrected voltage signals,
• wherein the detection device comprises:
• the detection unit, comprising a plurality of thickness detection chips, wherein the plurality of thickness detection chips are sequentially arranged at least in the second direction;
• and
• the common unit, arranged opposite and spaced from the detection unit in a first direction, wherein distances between at least two positions of a first surface of the common unit and the detection unit are different, the second direction is perpendicular to the first direction and the moving direction of the object to be detected, and the first surface is a surface of the common unit which is close to the detection unit.