HYDROGEN SENSOR

摘要

A hydrogen sensor includes a thin film layer formed over a substrate of resin or the like, and a catalyst layer formed on a surface of the thin film layer. When contacted by leaked hydrogen gas, the catalyst layer quickly hydrogenates the thin film layer through its catalytic action, thereby causing a change in optical reflectance of the thin film layer. The hydrogen sensor includes a protective film formed at least either between the substrate and the thin film layer or on a surface of the catalyst layer.