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:
May. 28, 2024
Filed:
Nov. 08, 2019
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
A sound field generation apparatus includes: a first modulation unit modulating an ultrasonic wave signal according to a prescribed modulation system; a second modulation unit modulating the ultrasonic wave signal according to a modulation system different from the modulation system of the first modulation unit; a filter unit changing frequency characteristics of an audible range signal used in modulation of the second modulation unit; a first ultrasonic wave output unit outputting a first ultrasonic wave signal modulated by the first modulation unit; and a second ultrasonic wave output unit outputting a second ultrasonic wave signal modulated by the second modulation unit, wherein the filter unit is set to have filter characteristics to cancel a first audible sound reproduced by the first ultrasonic wave signal with a second audible sound reproduced by the second ultrasonic wave signal at a control point provided outside the sound field.