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AssigneeFPS, Inc.
InventorsFumihito Meguro, Tomomi Nakatsuka, Masashi Hori, Hiromi Sotome, Masahiro Iwata, Kuniyuki Kobayashi
Estimating the term…
A flat acoustic transducer (100) includes a permanent magnet (10) and a magnetic member (20), which are arranged adjacent to each other with a predetermined interval, a flat vibrating membrane (30), provided facing the permanent magnet (10) and the magnetic member (20), and at least one coil (40), fixed to the vibrating membrane (30). In the flat acoustic transducer (100), an electrical signal is applied to the coil (40), to obtain vibration force (F) on the vibrating membrane (30) by way of a magnetic flux Φ generated between a magnetic pole face (12) of the permanent magnet (10) and the magnetic member (20), a step (50) is provided between the magnetic pole face (12) and the upper face (22) of the magnetic member (20), while at least part of a winding (42) of the coil (40) at the time of no application of an electrical signal is arranged inside the step (50).
A flat acoustic transducer comprising:
A method for driving a flat acoustic transducer that has a flat vibrating membrane fixed with at least one coil to which an electrical signal is applied, wherein a static magnetic field is generated such that a density of a magnetic flux component parallel to a coil face of said coil changes in a vibrating direction of said vibrating membrane, a step is provided between a magnetic pole face and the upper face of a magnetic member, and at least part of a winding of said coil at the time of no application of said electrical signal is arranged inside said step and said electrical signal is applied to said coil arranged at such a position that the density of said magnetic flux component is maximal, to vibrate said vibrating membrane.
Dependencies are inferred from the claim text.