Single crystal thickness and width cuts for enhanced ultrasonic transducer

US6465937B1 · kind B1 · utility

Assignee

• KONINKLIJKE PHILIPS ELECTRONICS NV · NL

Inventors

• Jie Chen · New Taipei, TW
• Rajesh Kumar PANDA · New Brunswick, US
• Turuvekere R. Gururaja · North Andover, US
• Heather Beck · Chelmsford, US

Key dates

• Filing date: Mar 8, 2000
• Grant date: Oct 15, 2002
• Expiry date: Mar 8, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10N30/8548

Abstract

This invention is directed to a transducer comprising a lead-based single crystal wherein the crystal is diagonally oriented and has an effective coupling constant of at least 0.70. In one embodiment, the lead-based crystal has the formula Pb(B′B″)O3—PbTiO3 wherein B′ is Mg2+, Zn2+, Ni2+ or Sc3+ and B″ is Nb5+, Ta5+ or W6+. Preferably, the lead-based crystal has of the formula Pb(B′B″)O3—PbTiO3 where B′ is Mg2+, Zn2+, Sc3+ and B″ is Nb5+ or more specifically Pb(Mg1/3Nb2/3)O3—PbTiO3 (“PMN—PT”), Pb(Zn1/3Nb2/3)O3—PbTiO3 (“PZN—PT”), and Pb(Sc1/3Nb2/3)O3—PbTiO3 (“PSN—PT”).The invention also includes a transducer comprising a plurality of lead-based single crystal transducers. In one embodiment the ultrasonic probe comprising one or more piezoelectric components having surfaces that function as transmitting and/or receiving elements; and electrodes placed upon opposite surfaces of the elements, and wherein each lead based piezoelectric component as described above. In addition, the invention includes improved materials for reduced spurious modes. Furthermore…