Patent ID: 6047590
Filing Date: 2000-04-11
Classification: G01L,G01N

Abstract:
A sensor device, comprising:a base body having a vibrating portion;a piezoelectric element fixed onto one surface of said vibrating portion and having a piezoelectric film and a pair of electrodes which are in contact with said piezoelectric film;a space that allows a fluid to lead to the other surface of said vibrating portion; andintroduction holes that communicate with said space;wherein said sensor device is in a longitudinal shape, a plurality of introduction holes are provided, a first recess which contains at least opening ends of a part of introduction holes on the surface side of the sensor device in its region and extends continuously up to the rear end portion of the sensor device and a second recess which contains at least opening ends of other introduction holes on the surface side of the sensor device in its region are formed by a protrusion disposed on the surface of the sensor device, and the protrusion is covered with a cap member, in such a manner that a cylindrical space that opens only on a side of the rear end portion of the sensor device is formed by said protrusion, said cap member and said first recess, and said first recess and said second recess are isolated from each other.