Airborne ultrasonic electrostatic transducers with conductive grooved backplates: tailoring their centre frequency, sensitivity and bandwidth

Schindel, 1997, Air-coupled ultrasonic NDE of bonded aluminium lap joints, Ultrasonics, 35, 1, 10.1016/S0041-624X(96)00088-1 Schindel, 1995, Applications of micromachined capacitance transducers in air-coupled ultrasonics and nondestructive evaluation, IEEE Trans. UFFC, 42, 51, 10.1109/58.368313 Schindel, 1995, Through thickness characterisation of solids by wideband air-coupled ultrasound, Ultrasonics, 33, 11, 10.1016/0041-624X(95)00011-Q Grandia, 1995, NDE applications of air-coupled ultrasonic transducers, vol. 1, 697 Hosten, 1996, Measurements of elastic constants in composite materials using air-coupled ultrasonic bulk waves, J. Acoust. Soc. Am., 99, 2116, 10.1121/1.415398 Schindel, 1992, Capacitance devices for the generation of air-borne ultrasonic fields, vol. 2, 843 Carr, 1993, Diagnostic measurements in capacitive transducers, Ultrasonics, 31, 13, 10.1016/0041-624X(93)90028-X Wykes, 1993, Advances in air-borne ultrasonic sensors, 667 H. Carr, Electrostatic transducers for airborne ultrasonics, Thesis, University of Nottingham, UK, 1989. Hietanen, 1993, Factors affecting the sensitivity of electrostatic ultrasonic transducers, Meas. Sci. Technol., 4, 1138, 10.1088/0957-0233/4/10/018 Mattila, 1995, Electroacoustic model for electrostatic ultrasonic transducers with V-grooved backplates, IEEE Trans. UFFC, 42, 1, 10.1109/58.368320 Hietanen, 1992, A model for an electrostatic ultrasonic transducer with a grooved backplate, Meas. Sci. Technol., 3, 1095, 10.1088/0957-0233/3/11/013 Mattila, 1994, Bandwidth control of an electrostatic ultrasonic transducer, Sensors Actuators A:, 45, 203, 10.1016/0924-4247(94)00841-8 Hietanen, 1993, A Helmholtz resonator model for an electrostatic ultrasonic air transducer with a V-grooved backplate, Sensors Actuators A:, 39, 129, 10.1016/0924-4247(93)80209-Y Munro, 1994, Arrays for airborne 100kHz ultrasound, Ultrasonics, 32, 57, 10.1016/0041-624X(94)90081-7 Brown, 1996, Ultrasonic tomographic imaging of solid objects in air using an array of fan-shaped-beam electrostatic transducers, Ultrasonics, 34, 111, 10.1016/0041-624X(96)00027-3 Bashford, 1998, Micromachined ultrasonic capacitance transducers for immersion applications, IEEE Trans. UFFC, 45, 367, 10.1109/58.660148 Schindel, 1991, Capacitance devices for the controlled generation of ultrasonic fields in liquids, vol. 1, 301 Bashford, 1996, Characteristics of ultrasonic micromachined capacitance transducers in water, vol. 2, 955 Anderson, 1995, Broadband electrostatic transducers: modelling and experiments, J. Acoust. Soc. Am., 97, 262, 10.1121/1.412310 Haller, 1996, A surface micromachined electrostatic ultrasonic air transducer, IEEE Trans. UFFC, 43, 1, 10.1109/58.484456 Schindel, 1995, The design and characterization of micromachined air-coupled capacitance transducers, IEEE Trans. UFFC, 42, 42, 10.1109/58.368314 Thielemann, 1997, Capacitive silicon sensors for ultrasound, Acustica, 83, 715 Bashford, 1996, Radiated fields of an air-coupled ultrasonic capacitance transducer, Ultrasonics, 34, 169, 10.1016/0041-624X(95)00118-M Suzuki, 1989, A silicon electrostatic ultrasonic transducer, IEEE Trans. UFFC, 36, 620, 10.1109/58.39112 Eccardt, 1997, Micromachined transducers for ultrasound applications, vol. 2, 1609 Ladabaum, 1998, Surface micromachined capacitive ultrasonic transducers, IEEE Trans. UFFC, 45, 678, 10.1109/58.677612 Morse, 1986 Kinsler, 1982