title: Thermoelastic expansion vs. piezoelectricity for high-frequency, 2-D arrays.
abstract: Optical generation using the thermoelastic effect has traditionally suffered from low conversion efficiency. We previously demonstrated increased efficiency of nearly 20 dB with an optical absorbing layer consisting of a mixture of polydimethylsiloxane (PDMS) and carbon black spin coated onto a glass microscope slide. In this paper we show that the radiated power from a black PDMS film is comparable to a 20 MHz piezoelectric two-dimensional (2-D) array element. Furthermore, we predict that a thermoelastic array element can produce similar acoustic power levels compared to ideal piezoelectric 2-D array elements at frequencies in the 100 MHz regime. We believe these results show that thermoelastic generation of ultrasound is a promising alternative to piezoelectricity for high-frequency, 2-D arrays.
authors.forename: Takashi
authors.initials: T
authors.lastname: Buma
authors.forename: Monica
authors.initials: M
authors.lastname: Spisar
authors.forename: Matthew
authors.initials: M
authors.lastname: O'Donnell
mesh_terms: D004129:Dimethylpolysiloxanes; D004548:Elasticity; D004867:Equipment Design / Q000379:methods; D019544:Equipment Failure Analysis; D008962:Models, Theoretical; D012680:Sensitivity and Specificity; D012828:Silicones; D013696:Temperature; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation* / Q000379:methods*; D014732:Vibration
chemical_list: D004129:Dimethylpolysiloxanes; D012828:Silicones; C013830:baysilon