Title :
Design and Optimization of a Capacitive Micromachined Ultrasonic Transducer Micro-Array for Near Field Sensing
Author :
Clarke, Clyde ; White, Carl ; Etienne-Cummings, Ralph
Author_Institution :
Dept. of Electr. & Comput. Eng., Morgan State Univ., Baltimore, MD
Abstract :
The design of a tool-tip mounted cMUT (capacitive micromachined ultrasonic transducer) micro-array for near field imaging of the retina is undertaken. For intra-vitreal applications, a uniformly excited NtimesN transducer array is limited to a size of 2mm times 2mm. The physical parameters of the array are constrained by the imaging requirements of a 2 mum resolution and a distance of 400 mum from the retinal surface. The mechanical and electrical parameters of the cMUT are calculated using a combination of the Mason equivalent circuit model and finite element techniques. Optimal transmit power and receive sensitivity for this imaging application are obtained by coupling the transducer model to a pseudo-spectral wave propagation model. The pseudo-spectral method is used to calculate the frequency dependent attenuation of the transmitted acoustic pulse through the vitreous and retinal media. The subsequent reflected wavefront is used to optimize the array transmit power and sensitivity
Keywords :
acoustic pulses; capacitive sensors; equivalent circuits; eye; finite element analysis; image sensors; microsensors; ultrasonic transducer arrays; 2 micron; 2 mm; 400 micron; Mason equivalent circuit model; acoustic pulse; capacitive micromachined ultrasonic transducer microarray; electrical parameters; finite element techniques; image resolution; mechanical parameters; near field imaging; near field sensing; pseudo-spectral wave propagation model; retina; retinal media; retinal surface; vitreous media; wavefront reflection; Acoustic imaging; Acoustic transducers; Coupling circuits; Design optimization; Equivalent circuits; Finite element methods; Image resolution; Retina; Ultrasonic imaging; Ultrasonic transducers;
Conference_Titel :
Circuits and Systems, 2007. ISCAS 2007. IEEE International Symposium on
Conference_Location :
New Orleans, LA
Print_ISBN :
1-4244-0920-9
Electronic_ISBN :
1-4244-0921-7
DOI :
10.1109/ISCAS.2007.378187
