An optical readout module (68) for an optical device comprises a support (70), a light source (74) and a light detector (76) provided in or on a first surface (80) of the support (70), and an optical component (72) formed in or fabricated on the support (70). The support (70) is or comprises a layer of overmolding material. The light source (74) is arranged to emit outbound light through the support (70), and the light detector (76) is arranged to detect inbound light that has propagated to the light detector (76) through the support (70). The optical component (72) is positioned so that in use the outbound light travels via the optical component (72) towards a target object; or so that in use the inbound light travels via the optical component (72) to the light detector (76). A method of manufacturing the optical readout module (68) comprises attaching the light source (74) and the detector to a substrate or wafer; applying the layer of overmolding material to the substrate or wafer; and forming the optical component (72) in the layer of overmolding material or fabricating the optical component (72) on the layer of overmolding material.
H01L 31/16 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof structurally associated with, e.g. formed in or on a common substrate with, one or more electric light sources, e.g. electroluminescent light sources, and electrically or optically coupled thereto the semiconductor device sensitive to radiation being controlled by the light source or sources
H01L 25/16 - Assemblies consisting of a plurality of individual semiconductor or other solid-state devices the devices being of types provided for in two or more different subclasses of , , , , or , e.g. forming hybrid circuits
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
where n is an integer; where Tz is the Talbot length, defined by:
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
where n is an integer; where Tz is the Talbot length, defined by:
T
z
=
λ
1
-
1
-
λ
2
p
2
,
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
where n is an integer; where Tz is the Talbot length, defined by:
T
z
=
λ
1
-
1
-
λ
2
p
2
,
where λ is the wavelength of the light, and where p is the grating period of the respective diffraction grating.
G01B 11/14 - Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
H04R 23/00 - Transducers other than those covered by groups
An optical microphone assembly including a substrate having a first and second substrate portions with the first substrate portion being thinner than the second substrate portion, an interferometic arrangement including a membrane and at least one optical element including a surface of the first substrate portion and/or is disposed on a surface of the first substrate portion, and the at least one optical element does not include a diffractive optical element formed as a plurality of holes through the first substrate portion. The optical microphone assembly further includes a light source 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, and with at least one of the first and second paths passing through the first substrate portion, and at least one photo detector arranged to detect at least part of an interference pattern generated by said first and second portions of light dependent on the optical path difference.
H04R 23/00 - Transducers other than those covered by groups
G01B 11/14 - Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
G01D 5/26 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using optical means, i.e. using infrared, visible or ultraviolet light
An optical accelerometer including an interferometric arrangement, a light source, a photodetector, a support structure that is static relative to the light source and photo detector, and a dual-layer membrane that is deflectable relative to the support structure. The dual-layer membrane includes first and second membrane layers that are mechanically coupled by a proof mass that is positioned between and attached to or integrally formed with the membrane layers. The interferometric arrangement includes a first optical element which includes or is disposed on a surface of one of the membrane layers and which is moveable relative to a second optical element which includes or is disposed on a surface of the support structure. The second optical element and at least part of the support structure are positioned between the membrane layers. The light source provides light to the interferometric arrangement and the photo detector detects an interference pattern generated by the light that is dependent on a distance between the first and second optical elements.
G01P 15/093 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by photoelectric pick-up
G01P 15/08 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values
G01P 15/13 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by measuring the force required to restore a proofmass subjected to inertial forces to a null position
09 - Scientific and electric apparatus and instruments
37 - Construction and mining; installation and repair services
42 - Scientific, technological and industrial services, research and design
Goods & Services
Cinematographic and optical apparatus and instruments, apparatus for recording, transmitting and reproducing sound and images; data processing equipment, computers; computer software; computer software for digital signal processing; aerials; loudspeakers; remote controls for audiological equipment; audio receiver apparatus; sensors and detectors; electrical sensors; silencers; electronic equipment, including microphones; microphones; microphone mixers; transformers; audio amplifiers; audio upgrade card; boom poles for sound transmission apparatus; combined headphones and microphones; hands-free microphones for mobile phones; headphones; earphones; all of the aforegoing specifically being for components for the goods, and not finished products Installation, repair and maintenance services related to electronic devices; all of the aforegoing services specifically being in relation to components and not finished products Scientific and technological services and research and development related thereto; industrial analysis and research; design and development of computers and computer programs; engineering [technical expertise]; technical consultancy in the field of audio technology; all of the aforegoing services specifically being in relation to components and not finished products
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
where n is an integer; where Tz is the Talbot length, defined by:
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
where n is an integer; where Tz is the Talbot length, defined by:
T
z
=
λ
1
-
1
-
λ
2
p
2
,
An optical displacement sensor comprises a reflective surface and one or more diffraction gratings which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface is moveable relative to the diffraction grating(s) or vice versa. Light from a light source propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors. Each interference pattern depends on the separation between the reflective surface and the respective grating. A collimating optical arrangement at least partially collimates the light between the light source and the diffraction grating(s). For the or each interferometric arrangement, when the reflective surface or the diffraction grating is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating and the reflective surface satisfies the relationship:
L
=
T
z
n
2
,
to within 20% of
T
z
2
,
where n is an integer; where Tz is the Talbot length, defined by:
T
z
=
λ
1
-
1
-
λ
2
p
2
,
where λ is the wavelength of the light, and where p is the grating period of the respective diffraction grating.
G01B 11/14 - Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
H04R 23/00 - Transducers other than those covered by groups
An optical microphone module for installation in a microphone assembly is described. The module is manufactured by assembling a semiconductor chip, a spacer and an interferometric component in a stack with the spacer disposed between the semiconductor chip and the interferometric component. The interferometric component comprises a membrane and a substrate comprising an optical element spaced from the membrane. The semiconductor chip comprises an optoelectronic circuit including at least one photo detector and has a light source mounted thereon or integrated therein. The light source is disposed to provide light to the interferometric arrangement such that two light portions propagate via respective optical paths to create an interference pattern at the photo detector which is dependent on a position of the membrane. The stack comprises an internal cavity and at least one aperture providing a passage for air between the internal cavity and an exterior of the stack, such that the internal cavity is in fluid communication with the exterior of the stack. A first side of the membrane is in fluid communication with the exterior of the stack and a second side of the membrane is in fluid communication with the internal cavity.
G02F 1/015 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction
G02F 1/29 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the position or the direction of light beams, i.e. deflection
H04R 1/04 - Structural association of microphone with electric circuitry therefor
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). The hole(s) are positioned such that at least one of the first and second optical paths at least partly overlaps with the hole(s). 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 the optical path difference.
H04R 23/00 - Transducers other than those covered by groups
G01B 11/14 - Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
G01D 5/26 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using optical means, i.e. using infrared, visible or ultraviolet light
09 - Scientific and electric apparatus and instruments
37 - Construction and mining; installation and repair services
42 - Scientific, technological and industrial services, research and design
Goods & Services
Apparatus for recording, transmission or reproduction of sound or images; Magnetic data media; Recording discs; Compact discs; DVDs; Digital recording media; Blank digital recording media; Digital data recording media; Coin-operated mechanisms; Cash registers; Calculating machines; Data processing equipment; Computers; Computer software; Fire extinguishing apparatus; Computer software for digital signal processing; Aerials; Loudspeakers; Remote controls for audiological devices; Audio devices and radio receivers; Sensors and detectors; Electric sensors; Noise suppressors [electrical components]; Electronic devices, namely microphones; Electrical filters; Microphones; Microphone mixers; Transformers [electricity]; Audio amplifiers; Sound upgrade cards; windshields for microphones; Microphone cables; Microphone stands; Microphone plugs; Microphone buttons; Boom poles for sound transmission apparatus; Headphone-microphone combinations; Hands-free microphones for cell phones; Cases and stands for microphones and microphone devices; Headphones; In-ear headphones; Cinematographic machines and apparatus; Optical apparatus and instruments; Weighing apparatus and instruments; Nautical apparatus and instruments; Surveying apparatus and instruments; Measuring apparatus and instruments; Checking (supervision) apparatus and instruments; Signalling apparatus and instruments; Life-saving apparatus and instruments; Scientific apparatus and instruments; Apparatus and instruments for controlling electricity; Apparatus and instruments for accumulating electricity; Apparatus and instruments for switching electricity; Apparatus and instruments for transforming electricity; Apparatus and instruments for regulating electricity; Apparatus and instruments for conducting electricity; all of the aforegoing specifically being for components for the goods, and not finished products. Installation, repair and maintenance services related to electronic devices; all of the aforegoing services specifically being in relation to components and not finished products. Industrial analysis and research services; Design and development of computer hardware and software; Engineering services; Technical consultancy in relation to audio technology; Technical consultancy in relation to microphones; Science and technology services; Technological research; Scientific services and design relating thereto; Technological services and design relating thereto; Scientific research; all of the aforegoing services specifically being in relation to components and not finished products.
An optical displacement sensor (2) comprises a reflective surface (4) and one or more diffraction gratings (6) which, together with the reflective surface, each define a respective interferometric arrangement. The reflective surface (4) is moveable relative to the diffraction grating(s) (6) or vice versa. Light from a light source (8) propagates via the interferometric arrangement(s) to produce an interference pattern at a respective set of photo detectors (10). Each interference pattern depends on the separation between the reflective surface (4) and the respective grating (6). A collimating optical arrangement (14) at least partially collimates the light between the light source (8) and the diffraction grating(s) (6). For the or each interferometric arrangement, when the reflective surface (4) or the diffraction grating (6) is in a zero-displacement position, the optical path length L of the light propagating between the diffraction grating (6) and the reflective surface (4) satisfies the relationship: to within 20% of j, where n is an integer; where Tz is the Talbot length, defined by: where λ is the wavelength of the light, and where p is the grating period of the respective diffraction grating (6). Alternatively, L may satisfy: to within 20% of p where m is an odd integer. Additionally or alternatively, the optical displacement sensor (34; 112) may comprise two or more diffraction gratings (44, 46; 116) and may be configured to provide a respective separate light beam (62, 64; 132) to each grating (44, 46; 116) using a beam-separating arrangement (48; 126) or plural light source elements.
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. 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 such that at least one of the first and second portions is reflected by the reflecting surface of the membrane, 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 at least one photo detector is arranged to detect at least part of an interference pattern generated by the first and second portions of light dependent on the optical path difference.
An optical microphone module (2) for installation in a microphone assembly is described. The module (2) is manufactured by assembling a semiconductor chip (4), a spacer (6) and an interferometric component (8) in a stack with the spacer (6) disposed between the semiconductor chip (4) and the interferometric component (8). The interferometric component (8) comprises a membrane (12) and a substrate (10) comprising an optical element (14) spaced from the membrane (12). The semiconductor chip (4) comprises an optoelectronic circuit (20) including at least one photo detector (18) and has a light source (16) mounted thereon or integrated therein. The light source (16) is disposed to provide light to the interferometric arrangement (8) such that two light portions (26, 28) propagate via respective optical paths to create an interference pattern at the photo detector (18) which is dependent on a position of the membrane (12). The stack comprises an internal cavity (30) and at least one aperture (40) providing a passage for air between the internal cavity (20) and an exterior (34) of the stack, such that the internal cavity (30) is in fluid communication with the exterior (34) of the stack. A first side of the membrane (12) is in fluid communication with the exterior (34) of the stack and a second side of the membrane (12) is in fluid communication with the internal cavity (30).
An optical microphone assembly (2) comprises a substrate (4), an interferometric arrangement, a light source (8) and at least one photo detector (10). The interferometric arrangement comprises a membrane (6) and at least one diffractive optical element (20, 22) spaced from the membrane (6). The diffractive optical element(s) (20, 22) comprise a plurality of lines (24) formed in or disposed on a surface of the substrate (4) and being arranged in a first pattern. The substrate (4) comprises one or more holes (32) extending fully therethrough, the hole(s) (32) being arranged in a second pattern that is different from the first pattern. The light source (8) is arranged to provide light (26) to the interferometric arrangement such that first and second portions (28, 30) of the light (26) propagate along respective, different first and second optical paths via said interferometric arrangement. An optical path difference between the first and second optical paths depends on a distance between the membrane (6) and the diffractive optical element(s) (20, 22). The hole(s) (32) are positioned such that at least one of the first and second optical paths at least partly overlaps with the hole(s) (32). The photo detector(s) (10) 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.
H04R 23/00 - Transducers other than those covered by groups
G01B 11/02 - Measuring arrangements characterised by the use of optical techniques for measuring length, width, or thickness
G01D 5/26 - Mechanical means for transferring the output of a sensing memberMeans for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for convertingTransducers not specially adapted for a specific variable using optical means, i.e. using infrared, visible or ultraviolet light
G01D 5/38 - Forming the light into pulses by diffraction gratings
An optical microphone assembly (2) comprises a micro-electromechanical system (MEMS) component (4), a semiconductor chip (6), and an outer housing including at least part of a non-MEMS supporting structure and defining an aperture (32). The MEMS component comprises an interferometric arrangement, which comprises a membrane (8) and at least one optical element (10) spaced from the membrane (8). The semiconductor chip (6) comprises at least one photo detector (14) and has mounted thereon or integrated therein a light source (16). The MEMS component (4) is mounted on the non-MEMS supporting structure and sealed to the outer housing such that the MEMS component (4) closes the aperture (32). The semiconductor chip (6) is mounted separately from the MEMS component (4) on the non-MEMS supporting structure in a spaced relationship with the MEMS component (4) such that the MEMS component (4) is displaced relative to the semiconductor chip (6) in a direction perpendicular to a reflecting surface of the membrane (8). The light source (16) is arranged to provide light (38) to the interferometric arrangement such that a first portion (40) of said light propagates along a first optical path via said interferometric arrangement and a second portion (42) of said light propagates along a second, different optical path via said interferometric arrangement such that at least one of said first and second portions (40, 42) is reflected by the reflecting surface of the membrane (8), thereby giving rise to an optical path difference between the first and second optical paths which depends on a distance between the membrane (8) and the optical element (10). The at least one photo detector (14) is arranged to detect at least part of an interference pattern generated by said first and second portions (40, 42) of light dependent on said optical path difference.
