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Patents on electrostatic headphones


Patent number


Filed / Granted Available
5,206,914 Neil K. Fortney (Koss) Electrostatic Acoustic Transducer Having Extremely Thin Diaphragm Substrate. Electrostatic transducer design employing a diaphragm coated with infrared-transparent material for high performance. 4/27/1993  
3,896,274 Freeman Frahm.Electret Earphone . Electret transducer design with improved polarization stability.
G.B. Patent 1,234,767 (PDF, 730 KB) (Willy Lefevbre, June 2001) Enock Describes electrostatic transducers in which the stators are insulated to allow the use of high operating voltages, thereby increasing the sensitivity
of the transducers.
June 1971 Available on exchange basis



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