Elastic surface wave devices and method for making the same

摘要

This invention provides a surface elastic wave device constituted by a unitary body of a piezoelectric plate having a pair of transducers thereon, which unitary body is embedded in a casing, and wherein the wave propagation of a surface elastic wave generated on the surface of the piezoelectric plate during excitation of the device is prevented from being transferred to the casing by a thin film inserted between the casing and the wave propagation surface of the piezoelectric plate or by using as the casing a roll of flexible sheet which has the same function of wave propagation prevention as that of the thin film. This device is advantageous because it has a low spurious signal level without incrementing insertion loss, is easy to manufacture and is inexpensive. This invention also provides an effective method of making the device.