A filter includes a filter plate provided with a through holes formation portion in which a plurality of through holes is formed, a ring-shaped piezoelectric layer arrangement portion on an upper surface of which a piezoelectric layer is formed, and a circular-shaped fixed portion fixed to a tube, an electrode formed almost on an entire area on an upper surface of the piezoelectric layer, and a protective layer covering the piezoelectric layer and the electrode. When a driving electric potential is applied to the electrode, an electric field is generated in the piezoelectric layer, and the piezoelectric layer is contracted to deform the filter plate. With the deformation of the filter plate, the filter vibrates, and it is possible to release impurities and air bubbles in a liquid trapped in the filter. Accordingly, it is possible to realize a long life of the filter.