.~.~ Piezoelectric slab having different resonant frequencies at different areas
DEFINITION
Classification: 310/320
Piezoelectric slab having different resonant frequencies at different areas:
(under subclass 311) Subject matter wherein a unit of piezoelectric material is disclosed as having a resonant
region and at least one other region that has a deliberately different resonant frequency from the first resonant region, e.g., energy trapped, dot resonator, or monolithic filter devices.
(1) Note. Devices which use the energy trapping concept are specifically included since the regions in which the energy is trapped (usually under electrodes) must be different from that of the surrounding region (usually not electrodes). Thus, even if the device has only one resonator, it has two regions with different resonant frequencies. The same reasons apply to monolithic filters.
(2) Note. Typical ways of providing different resonant frequencies on the same slab of piezoelectric material are loading portions of the material, or removing portions of the material, or providing changes in the cross section of the slab.
SEE OR SEARCH THIS CLASS, SUBCLASS:
322, for acoustic wave generators which may utilize a wedge or other shape element which has different resonant frequencies in different areas.
SEE OR SEARCH CLASS
333, Wave Transmission Lines and Networks, 187+, for electric filters that may utilize such a piezoelectric slab.
