Exhalation sensor, expiration sensor unit, and expiration detection method

摘要

A breath sensor includes a base body, a first electrode provided on a part of a surface of the base body, a second electrode provided on a part of the surface of the base body, and a covering layer made of a material that does not pass moisture therethrough, the covering layer covering the second electrode with the base body. The base body is preferably made of a material whose surface potential changes due to attachment of moisture to one of a surface of the first electrode and the surface of the base body. A surface potential on a side of the first electrode of the base body changes when a breath containing moisture touches the surface of the first electrode.