The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 20, 2007
Filed:
Apr. 08, 2002
Guido Kolano, Salach, DE;
Klaus Linhard, Schelklingen, DE;
Guido Kolano, Salach, DE;
Klaus Linhard, Schelklingen, DE;
DaimlerChrysler AG, Stuttgart, DE;
Abstract
A parametric loudspeaker system is described which is based upon the FM-modulation of an ultrasound carrier. Known systems work with AM-modulation. The FM-modulation produces a good matching to the resonant transducer such as the conventionally employed piezo-ceramic transducers. The resonance slope of the transducers is used for FM/AM-conversion. This FM-resonance principle can advantageously be employed in a multi-path loudspeaker system, in which the transducer works in the optimal resonance range in each of the paths. With the conventional AM-modulation this is not possible. The FM-resonance principle can also be used in resonance-free or resonance-poor transducers, such as for example electrostatic transducers.