Abstract: An optical microphone assembly including a substrate, an interferometric arrangement, a light source, and at least one photo detector. The interferometric arrangement includes a membrane and at least one diffractive optical element spaced from the membrane. The diffractive optical element(s) include a plurality of lines formed in or disposed on a surface of the substrate and arranged in a first pattern. The substrate includes one or more holes extending fully therethrough, the hole(s) arranged in a second pattern that is different from the first pattern. The light source is arranged to provide light to the interferometric arrangement such that first and second portions of the light propagate along respective, different first and second optical paths via the interferometric arrangement. An optical path difference between the first and second optical paths depends on a distance between the membrane and the diffractive optical element(s).

Abstract: An optical microphone assembly including a micro-electromechanical system (MEMS) component, a semiconductor chip, and an outer housing including at least part of a non-MEMS supporting structure and defining an aperture. The MEMS component includes an interferometric arrangement which includes a membrane and at least one optical element spaced from the membrane. The semiconductor chip includes at least one photo detector and a light source. The MEMS component is mounted on the non-MEMS supporting structure and sealed to the outer housing such that the MEMS component closes the aperture. The semiconductor chip is mounted separately from the MEMS component on the non-MEMS supporting structure in a spaced relationship with the MEMS component such that the MEMS component is displaced relative to the semiconductor chip in a direction perpendicular to a reflecting surface of the membrane.

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.

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.