| 摘要 |
PROBLEM TO BE SOLVED: To correctly measure a viscosity or the like of a liquid by liquid- tightly covering input/output electrodes and a conductive member without setting a substance to a propagation face of surface acoustic waves for changing an attenuation factor of surface acoustic waves in accordance with a temperature change in a surface acoustic wave apparatus for measuring characteristic values of the liquid. SOLUTION: The surface acoustic wave apparatus 40 is composed of a surface acoustic wave device 42 set on a base 41 and having combed input/output electrodes 44 and 45 arranged on a piezoelectric substrate 43 in parallel along a propagation direction of surface acoustic waves, and a plurality of metallic wires 49a, 49b, 49c and 49d led out from the input/output electrodes 44 and 45 respectively. An insulating layer 48 is formed to an upper face of the surface acoustic wave device 42, which liquid-tightly covers the input/output electrodes 44 and 45. Covers 54a and 54b are set to an upper face of the base 41 to liquid- tightly cover the wires 49a, 49b, 49c and 49d with leaving a sensing face 43a including the input/output electrodes 44 and 45 with spaces S. |
