Patent ID: 8246800

Claim:
A gas sensor for detecting a predetermined gas component in a measurement gas, comprising: a sensor element; one or more openings provided at a forward end of said sensor element, for introducing the measurement gas from an outside of said sensor element, wherein said one or more openings are elongated and substantially rectangular, and a sum of sizes in a thickness direction of said one or more openings is greater than or equal to 8 μm and less than or equal to 60 μm; and a porous layer provided on a side surface of said sensor element so as to cover a region of said side surface to a back end of said sensor element, said porous layer consisting of a porous body having a higher porosity than a constituent material for said side surface of said sensor element, wherein said porous layer is positioned along the entirety of said side surface apart from said forward end of said sensor element by a distance greater than or equal to 2 mm, wherein said porous layer continuously extends towards and terminates at the back end of said sensor element, and wherein said side surface of said sensor element consists of a dense water-repellent material.