Patent ID: 9197965
Filing Date: 2015-11-24
Classification: H04R

Abstract:
1. A planar-magnetic transducer device for generating an acoustic output based on an electrical signal, comprising; a support frame, a diaphragm including a first surface side and a second surface side, where a perimeter portion of the diaphragm is supported by the support frame such that a vibratable portion of the diaphragm is held in a predetermined state of tension, a conductive trace pattern formed on the diaphragm and arranged to receive an electrical input signal, a primary magnetic structure including at least one primary magnet row coupled to the support frame, where each primary magnet row is positioned adjacent to, and spaced a predetermined distance from, the first surface side of the vibratable portion of the diaphragm and is operable as a fringe field source interacting with at least a portion of the conductive trace pattern, at least one secondary magnetic structure positioned at a first lateral side of the transducer device, the secondary magnetic structure including at least one secondary magnet with the secondary magnet having a first magnetic polarity surface and a second magnetic polarity surface, where a magnetically conductive focusing pole is attached to the first magnetic polarity surface of the at least one secondary magnet, the at least one secondary magnetic structure is mounted to the support frame and positioned above a plane of the second surface side of the diaphragm with the at least one secondary magnet positioned laterally outside of the vibratable portion of the diaphragm, the magnetically conductive focusing pole of the secondary magnetic structure operable as a focused field magnetic source interacting with at least a portion of the conductive trace pattern, and the electrical signal is applied to the conductive trace pattern such that the primary magnet row fringe field and the secondary magnetic structure focused field cause movement of the conductive trace pattern and the vibratable portion of the diaphragm, thereby generating the acoustic output.