By Topic

Performance and Modeling of a Fully Packaged Micromachined Optical Microphone

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$33 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Michael L. Kuntzman ; Department of Electrical and Computer Engineering, The University of Texas at Austin , Austin, TX, USA ; Caesar T. Garcia ; A. Guclu Onaran ; Brad Avenson
more authors

A microelectromechanical systems (MEMS) optical microphone that measures the interference of light resulting from its passage through a diffraction grating and reflection from a vibrating diaphragm is described ( JASA, v. 122, no. 4, 2007). In the present embodiment, both the diffractive optical element and the sensing diaphragm are micromachined on silicon. Additional system components include a semiconductor laser, photodiodes, and required readout electronics. Advantages of this optical detection technique have been demonstrated with both omnidirectional microphones and biologically inspired directional microphones. In efforts to commercialize this technology for hearing aids and other applications, a goal has been set to achieve a microphone contained in a small surface-mount package (occupying 2 × 2 mm × 1 mm volume), with ultralow noise (20 dBA) and a broad frequency response (20 Hz-20 kHz). Such a microphone would be consistent in size with the smallest MEMS microphones available today but would have noise performance characteristics of professional-audio microphones significantly larger in size and more expensive to produce. This paper will present several unique challenges in our effort to develop the first surface-mount packaged optical MEMS microphone. The package must accommodate both optical and acoustical design considerations. Dynamic models used for simulating frequency response and noise spectra of fully packaged microphones are presented and compared with measurements performed on prototypes.

Published in:

Journal of Microelectromechanical Systems  (Volume:20 ,  Issue: 4 )