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. 01, 2022
Filed:
May. 15, 2019
Sintef Tto As, Trondheim, NO;
Hallvard Angelskår, Oslo, NO;
Thor Bakke, Lysaker, NO;
Ib-Rune Johansen, Oslo, NO;
Matthieu Lacolle, Nesøya, NO;
Jakob Vennerød, Oslo, NO;
Andreas Vogl, Oslo, NO;
Dag Wang, Oslo, NO;
SINTEF TTO AS, Trondheim, NO;
Abstract
An optical microphone assembly comprises a rigid substrate; an interferometric arrangement, a light source, at least one photo detector and an enclosure. The interferometric arrangement comprises a membrane and at least one optical element spaced from the membrane, wherein the at least one optical element comprises a surface of the substrate and/or is disposed on a surface of the substrate. The light source is arranged to provide light to the interferometric arrangement such that a first portion of the light propagates along a first optical path via the interferometric arrangement and a second portion of the light propagates along a second different optical path via the interferometric arrangement, thereby giving rise to an optical path difference between the first and second optical paths which depends on a distance between the membrane and the optical element. The photo detector(s) are arranged to detect at least part of an interference pattern generated by said first and second portions of light dependent on said optical path difference. The enclosure is arranged to form an acoustic cavity in fluid communication with one side of the membrane. The volume of the acoustic cavity is at least 3 mm multiplied by d, where d is a diameter of the membrane.