Title : 
Transducer material characterization by transmission coefficient measurements
         
        
            Author : 
Lu, X.M. ; Rhyne, T.L. ; Tea, N. ; Smith, L.S.
         
        
            Author_Institution : 
GE Med. Syst., Milwaukee, WI, USA
         
        
        
        
        
        
            Abstract : 
In transducer material characterization, quarter wave matching layer samples are often measured at higher than desired operating frequency. We describe a method for estimating both acoustic velocity and attenuation through transmission coefficient (TC) measurements of a thin layer. This method was used for characterizing a silicon-epoxy 2-2 composite layer around the quarter wavelength frequency range. The magnitude of TC for the composite agreed with prediction for a homogeneous material in the frequency range of interest. However, the measured phase showed a discontinuity (phase jump about 90°) near the quarter shear wave resonance for the epoxy
         
        
            Keywords : 
acoustic transducers; acoustic wave absorption; acoustic wave velocity; composite materials; polymers; silicon; Si; Si-epoxy 2-2 composite layer; acoustic attenuation; acoustic velocity; discontinuity; higher than desired operating frequency; phase jump; quarter shear wave resonance; quarter wave matching layer samples; quarter wavelength frequency range; transducer material characterization; transmission coefficient measurements; Acoustic measurements; Biomedical transducers; Composite materials; Frequency measurement; Impedance; Thickness measurement; Ultrasonic transducers; Ultrasonic variables measurement; Velocity measurement; Wavelength measurement;
         
        
        
        
            Conference_Titel : 
Ultrasonics Symposium, 1998. Proceedings., 1998 IEEE
         
        
            Conference_Location : 
Sendai
         
        
        
            Print_ISBN : 
0-7803-4095-7
         
        
        
            DOI : 
10.1109/ULTSYM.1998.765011