INFRARED SENSOR

PROBLEM TO BE SOLVED: To provide an infrared sensor for achieving a low cost of an optical lens and an infrared incident filter by sufficiently holding airtightness in a package. SOLUTION: The infrared sensor includes a cap having a window part at a position opposed to a sensor chip by being fixed on a stem while storing the sensor chip, a Fresnel lens arranged in the cap so as to block the window part, an inner for forming a through-hole passing an infrared ray from a detection object on the center part by being arranged to be fitted to the inside of the cap so as to push the Fresnel lens to the window part side, and the infrared incident filter adhered to the inner by blocking the through-hole of the inner. COPYRIGHT: (C)2009,JPO&INPIT