Abstract: There is provided an optical navigation module including an optical package and a light reflective element. The optical package includes an image sensor which has a sensor surface. The light reflective element is configured to reflect light propagating parallel to the sensor surface to light propagating perpendicular to the sensor surface to impinge on the sensor surface thereby performing the lateral detection.

Abstract: A gyroscope, an electronic device and a method of detecting an angular velocity. The gyroscope includes: a photoelectric detector and a light source, wherein the light source is movable relative to the photoelectric detector, and light emitted by the light source is able to be irradiated onto the photoelectric detector.

Abstract: The invention relates to a device for detecting acceleration. The device contains: a frame; a mass; a lever arm connected to the mass, wherein the mass is provided at a first lever position; an optical fiber having a fiber-optic sensor; and a compensation element for disturbance variables, wherein the compensation element for disturbance variables is connected to the lever arm or the mass and wherein the compensation element for disturbance variables is connected to the frame.

Abstract: An accelerometer device (100) comprises a former (118) and an optical fiber (120) wound around the former. The winding of optical fiber (120) has a sensing portion (126) that is free to move in relation to a direction of desired sensitivity (128). A movable element (106) is disposed opposite the sensing portion (126) of the optical fiber (120), the movable element (106) being translatable so as to urge against the sensing portion (126) of the optical fiber (120) from a position external to the winding of the optical fiber (120) in order to vary a length of the optical fiber (120). The variation in the length of the optical fiber (120) caused by the moveable element (106) is indicative of an acceleration in the direction of desired sensitivity (128).

Abstract: A microelectromechanical systems (MEMS) device comprises an optical directional coupler comprising: a first waveguide having a first and a second end, wherein a light beam is introduced into the first end; a second waveguide having a third and a fourth end, wherein the light beam is evanescently coupled between the two waveguides in the central region; a first photodetector to detect first optical power in the light beam at the second end; and a second photodetector to detect second optical power in the light beam at the fourth end; a vibrating proof mass adjacent to the coupler in a first direction from the coupler, wherein when inertial forces are applied to the MEMS device in a second direction, the proof mass moves in the first direction; a processor to determine the displacement of the proof mass from the coupler as a function of the first and the second optical power.

Abstract: Control of the emission characteristics of a light source in a light field display poses a significant benefit in the resulting 3D display quality for current and future technologies. A design system for microcavity OLEDs of any wavelength is detailed, which combines theoretical background with FDTD optimizations, permitting microcavity design of any OLED configuration. The resulting output profiles for microcavity OLEDs designed and fabricated with this method are compared to standard OLEDs and provide a reduction in spectral bandwidth, and a decrease in angular output.

Abstract: A method for monitoring a wind turbine is described. The method comprises measuring acceleration by means of a fiber-optic acceleration sensor in a rotor blade of the wind turbine; opto-electronically converting an acceleration signal of the fiber-optic acceleration sensor; and filtering the opto-electronically converted acceleration signal by means of an analog anti-aliasing filter.

Abstract: An optical device formed of a mirror wafer, a cap wafer, and a glass wafer. The mirror wafer includes a first layer of electrically conductive material, a second layer of electrically conductive material, and a third layer of electrically insulating material between the first layer and the second layer. A mirror element is formed of the second layer of the mirror wafer, and has a reflective surface in the bottom of a cavity opened into at least the first layer. A good optical quality planar glass wafer can be used to enclose the mirror element when the mirror wafer, cap wafer, and glass wafer are bonded to each other.

Abstract: Control of the emission characteristics of a light source in a light field display poses a significant benefit in the resulting 3D display quality for current and future technologies. A design system for microcavity OLEDs of any wavelength is detailed, which combines theoretical background with FDTD optimizations, permitting microcavity design of any OLED configuration. The resulting output profiles for microcavity OLEDs designed and fabricated with this method are compared to standard OLEDs and provide a reduction in spectral bandwidth, and a decrease in angular output.

Abstract: The invention relates to methods of producing a cap substrate, to methods of producing a packaged radiation-emitting device at the wafer level, and to a radiation-emitting device. By producing a cap substrate, providing a device substrate in the form of a wafer including a multitude of radiation-emitting devices, arranging the substrates one above the other such that the substrates are bonded along an intermediate bonding frame, and dicing the packaged radiation-emitting devices, improved packaged radiation-emitting devices are provided which are advantageously arranged within a cavity free from organics and can be examined, still at the wafer level, in terms of their functionalities in a simplified manner prior to being diced.

Abstract: A proximity sensor for detecting non-contact detection of a target using a fiber optic strain sensor and a system for operating multiple such proximity sensors is disclosed. The proximity sensor includes an optic fiber that has an optic fiber strain sensor that is coupled to a mass that moves in response to the target. The mass can be a magnet that moves when a ferrous target is within the magnetic field of the magnet causing the magnet to move and apply strain to the optic fiber strain sensor. The optic strain sensor can include periodic variation in the refractive index of the optic fiber, such as a fiber Bragg grating. The proximity sensor can include a second fiber optic sensor that is sensitive to temperature or a second fiber optic strain sensor coupled to a second magnet that operates in opposition to the first magnet. A system coupling multiple proximity sensors can include an interrogator that has an optical power source and a detector, each coupled to a processor.

Abstract: Embodiments are directed to capturing data associated with an occurrence of an event via a battery-powered recorder, comprising: storing analog data in a delay circuit while a recording circuit is powered off, detecting, by a trigger circuit, the occurrence of the event while the recording circuit is powered off, powering-on the recording circuit based on the detection of the event, converting samples of analog data associated with the event provided by the delay circuit to a digital format while the recording circuit powers on, and storing the converted digital samples after the recording circuit has powered on, wherein a time delay associated with the delay circuit is greater than a time it takes for the recording circuit to power-on.

Abstract: The present disclosure relates to a microelectromechanical systems (MEMS) package having two MEMS devices with different pressures, and an associated method of formation. In some embodiments, the (MEMS) package includes a device substrate and a cap substrate bonded together. The device substrate includes a first trench and a second trench. A first MEMS device is disposed over the first trench and a second MEMS device is disposed over the second trench. A first stopper is raised from a first trench bottom surface of the first trench but below a top surface of the device substrate and a second stopper is raised from a second trench bottom surface of the second trench but below the top surface of the device substrate. A first depth of the first trench is greater than a second depth of the second trench.

Abstract: An inertial sensor calibration method and inertial sensor calibration apparatus. One or more diffraction patterns are generated by one or more fixed and/or moveable gratings (inertial sensors) illuminated by an atomically stabilized source attached to a base and detected by an imager. The grating and/or inertial sensor has a designed parameter value and an actual respective parameter value, such as motion or distance that can be determined upon ultra-precise measurement. Such ultra-precise measurement can be used to calibrate the grating or inertial sensor.

Abstract: The present disclosure relates to method of forming a MEMS device that mitigates the above mentioned difficulties. In some embodiments, the present disclosure relates to a method of forming a MEMS device, which forms one or more cavities within a first side of a carrier substrate. The first side of the carrier substrate is then bonded to a dielectric layer disposed on a micro-electromechanical system (MEMS) substrate, and the MEMS substrate is subsequently patterned to define a soft mechanical structure over the one or more cavities. The dielectric layer is then selectively removed, using a dry etching process, to release the one or more soft mechanical structures. A CMOS substrate is bonded to a second side of the MEMS substrate, by way of a bonding structure disposed between the CMOS substrate and the MEMS substrate, using a low-temperature bonding process.

Abstract: Provided are a torque transducer, a method for manufacturing the torque transducer, and a transmission for a vehicle using the torque transducer. The torque transducer includes a mechano-luminescent (ML) part disposed on a torque measuring object and an illumination sensor disposed to be spaced apart from the ML part.

Abstract: One embodiment includes an accelerometer system. The system includes a laser configured to emit an optical beam at a linear polarization. The system also includes an optical cavity system. The optical cavity system includes a mirror that is coupled to an accelerometer housing via a spring and is configured to reflect the optical beam. The optical cavity system also includes at least one photodetector configured to receive at least a portion of at least one of the optical beam and the reflected optical beam and to generate an acceleration signal that is indicative of motion of the mirror resulting from an external acceleration acting upon the accelerometer housing. The system further includes an acceleration processor configured to calculate a magnitude of the external acceleration based on the acceleration signal.

Abstract: In one aspect, an apparatus for estimating a characteristic of a sensor is disclosed that in one embodiment may include a chamber housing sensor, wherein the sensor includes a suspended movable force mass having an opening therethrough, a first partially reflective member that moves with the force mass and a second partially reflective member spaced from the first partially reflective member, a source of buoyant fluid configured to supply the buoyant fluid to the chamber at a plurality of pressures, a device for directing light to the first and second partially reflective members at a plurality of angles, a detector for providing signals corresponding to light passing through the second partially reflective member corresponding to each of the plurality of angles and each of the plurality of pressures, and a processor for determining the characteristic of the sensor from the signals provided by the detector.

Abstract: A fiber optic microseismic sensing system is provided. The system includes a plurality of nodes, each of the nodes including a surface portion, an underground portion, and an optical cable extending between the surface portion and the underground portion. The surface portion includes (1) an optical source for transmitting an optical signal along the optical cable to the underground portion, and (2) an optical receiver for receiving a return optical signal propagating along the optical cable from the underground portion. The underground portion includes at least one transducer, each of the at least one transducer including (1) a fixed portion configured to be secured to a body of interest, (2) a moveable portion having a range of motion with respect to the fixed portion, (3) a spring positioned between the fixed portion and the moveable portion, and (4) a mass engaged with the moveable portion.

Abstract: An accelerometer is included within the confined space and limited volume of a distal portion of a surgical instrument. The surgical instrument includes an end component, a joint coupled to the end component, a shaft coupled to the joint, and a force transducer and accelerometer apparatus. The force transducer and accelerometer apparatus is coupled between the joint and the shaft. The force transducer and accelerometer apparatus includes a force sensor and an accelerometer. The accelerometer includes an optic fiber having a Fiber Bragg Grating. Information acquired from the Fiber Bragg Grating is used to drive a vibro-tactile haptic feedback output device coupled to a master control arm surgeon grip.

Abstract: An optical sensor having one or more sensing interference elements is disclosed. A first detector function generates a coarse optical path difference signal for example using a discrete Fourier transform of a detected interference spectrum, and a second detector function generates a refined optical path difference signal using the coarse optical path difference signal and for example a cross correlation of the interference spectrum with one or more sets of periodic transfer functions.

Abstract: Technologies are generally described for operating and manufacturing optomechanical accelerometers. In some examples, an optomechanical accelerometer device is described that uses a cavity resonant displacement sensor based on a zipper photonic crystal nano-cavity to measure the displacement of an integrated test mass generated by acceleration applied to the chip. The cavity-resonant sensor may be fully integrated on-chip and exhibit an enhanced displacement resolution due to its strong optomechanical coupling. The accelerometer structure may be fabricated in a silicon nitride thin film and constitute a rectangular test mass flexibly suspended on high aspect ratio inorganic nitride nano-tethers under high tensile stress. By increasing the mechanical Q-factors through adjustment of tether width and tether length, the noise-equivalent acceleration (NEA) may be reduced, while maintaining a large operation bandwidth. The mechanical Q-factor may be improved with thinner (e.g., <1 micron) and longer tethers (e.

Abstract: An apparatus and method for measuring the sloshing in the cargo tank of a liquefied natural gas carrier is provided. The apparatus includes: a plate-shaped floating mat coupler which floats on the surface of the liquefied natural gas contained in the cargo tank of a liquefied natural gas carrier and moves in accordance with the movement of the liquefied natural gas; and an optical sensor measuring acceleration using optical sensor technology to measure acceleration when the floating mat coupler floats by being inserted in one or more positions in the floating mat coupler. The characteristics of the movement occurring in accordance with the sloshing of the liquefied natural gas in the cargo tank of a liquefied natural gas carrier, and the shock and deformation which the inner wall of the cargo tank is subjected to because of such movement, are measured at multiple angles.

Abstract: An optical accelerometer and method of determining an acceleration are disclosed. In one aspect, an accelerometer includes a light source, a substrate, a light guide attached to a first side of the substrate and configured to redirect light from the light source through the substrate. The accelerometer also includes a light detector, a proof mass attached to a second side of the substrate via one or more springs, wherein the second side is opposite the first side and wherein motion of the proof mass alters a characteristic of the light from the light source reaching the light detector, and a processor configured to determine an acceleration based on the characteristic of the light reaching the light detector.

Abstract: Methods, structures, devices and systems are disclosed for implementing optomechanical sensors in various configurations by using two optically coupled optical resonators or cavities that can be move or deform relative to each other. The optical coupling between first and second optical cavities to produce an optical resonance that varies with a spacing between the first and second optical cavities and provide the basis for the optomechanical sensing. Compact and integrated optomechanical sensors can be constructed to provide sensitive measurements for a range of applications, including motion sensing and other sensing applications.

Abstract: Gyroscopes based on optomechanical designs to provide sensitive sensing while providing relatively large bandwidth and dynamic range with enhanced noise performance.

Abstract: A sensor includes a housing adapted to be secured to a component within a system to be monitored by the sensor, an optical fiber, and a membrane spring assembly. The optical fiber includes a sensing portion containing a fiber Bragg grating that is able to undergo expansion and contraction resulting from movement of the optical fiber at a second location relative to a first location. The membrane spring assembly includes a membrane disc, wherein movement of a central portion thereof causes corresponding displacement of the optical fiber at the second location to cause expansion and contraction of the sensing portion of the optical fiber containing the fiber Bragg grating, which expansion and contraction effects a change in a light wavelength reflected by the fiber Bragg grating. The light wavelength reflected by the fiber Bragg grating can be used to measure movement of the central portion of the membrane disc.

Abstract: An accelerometer includes a proof mass and a frame that are formed in a handle layer of a silicon-on-an-insulator (SOI). The proof mass is separated from the frame by a back-side trench that defines a boundary of the proof mass. The accelerometer also includes a reflector coupled to a top surface of the proof mass. An optical detector is located above the reflector at the device side. The accelerometer further includes at least one suspension spring. The suspension spring has a handle anchor that extends downwards from the device side to the handle layer to mechanically support upward and downward movement of the proof mass relative to a top surface of the proof mass.

Abstract: A fiber optic accelerometer has a hollow body that supports an optical fiber therein so as to form a cantilever section, a fiber optic splitter coupled to a first end of the optical fiber and a light source for directing light into the optical fiber via a first branch of the optical splitter. A photo detector receives light conveyed through the optical fiber via a second branch of the optical splitter and measures an intensity of the received light. A reflective target supported at a second end of the hollow body is axially aligned with the second end of the optical fiber in the absence of force. Upon acceleration the cantilever section moves such that its position relative to the reflective target changes thereby reducing the instantaneous intensity of light reflected by the target into the second end of the optical fiber and measured by the photo detector.

Abstract: A device for detecting seismic acceleration includes a proof mass; a base for providing a sensor acceleration, relative to the proof mass, based on the seismic acceleration; and an optical fiber portion operatively connected between the proof mass and the base for providing a fiber tension based on the sensor acceleration. A fiber Fabry-Perot interferometer (FFPI) in the optical fiber portion provides an optical characteristic representative of the fiber tension. A compensator applies a compensating tension to the FFPI to compensate for a change of the optical characteristic due to a temperature change of the FFPI.

Abstract: There is provided an optical accelerometer including a first substrate, a second substrate, a spacer and a processing unit. The first substrate includes a frame, a movable member and at least one elastic member. Periodic slots are formed on the movable member along at least one direction to be served as a diffraction grating. The elastic member is connected between the frame and the movable member. The second substrate includes at least one sensing unit configured to detect a diffraction pattern formed by the diffraction grating. The spacer is disposed between the first substrate and the second substrate to define a predetermined height. The processing unit is coupled to the sensing unit and configured to calculate a 3D acceleration according to the diffraction pattern.

Abstract: A cantilever beam structural resonant-type integrated optical waveguide accelerometer, includes an input waveguide (1), a dissymmetrical structural Mach-Zehnder interferometer (2), a micro-mechanical vibration cantilever beam (3), a short curved waveguide (4) and an output waveguide (5); all the waveguide structures and the cantilever beam use the integrated optical micromachining technique, and the device single-scale integration can be realized by using the temperature-insensitive organic polymer optical waveguide structure and the organic polymer substrate, the key technique indexes such as detection sensitivity, dynamic range are extensively adjusted. The phase difference of the optical signal can be measured by detecting the optical intensity of the resonant frequency of the optical circuit so as to achieve high sensitive acceleration detection, and to be free from the effect of the ambient temperature disturbance and waveguide birefringence.

Abstract: A device and method measure an acceleration of a moving body. The device contains a solid body having a moving part and an internal cavity capable of allowing for a free movement of the moving part. The internal cavity has at least one wall forming a sloping track, the sloping track having a surface allowing for the free movement of the moving part on the sloping track between an initial position at rest and a distant position spaced from the initial position situated at an end of the internal cavity and reachable by the moving part during a variation in acceleration. The moving part moving from the initial position to the distant position in the internal cavity under an effect of the acceleration of the moving body. At least one detector is provide and is capable of detecting a presence of the moving part at the distant position.

Abstract: The transparent photodetector includes a substrate; a waveguide on the substrate; a displaceable structure that can be displaced with respect to the substrate, the displaceable structure in proximity to the waveguide; and a silicon nanowire array suspended with respect to the substrate and mechanically linked to the displaceable structure, the silicon nanowire array comprising a plurality of silicon nanowires having piezoresistance. In operation, a light source propagating through the waveguide results in an optical force on the displaceable structure which further results in a strain on the nanowires to cause a change in electrical resistance of the nanowires. The substrate may be a semiconductor on insulator substrate.

Abstract: An optical device is capable of controlling a projector, wherein the projector is capable of wirelessly receiving an image signal from a data source, combining an identification signal into the image signal to generate a projection signal, and projecting a projection image according to the projection signal. The optical device includes an optical sensor. The optical sensor is capable of sensing the identification signal of the projection image, outputting a detection signal corresponding to the identification signal and wirelessly transmitting the detection signal to the projector. A projection system including a projector and an optical sensor is provided as well.

Abstract: Optical accelerometers may be provided that detect acceleration in up to six axes. An optical accelerometer may include an image sensor and optical elements such as light pipes that extend over the image sensor. Light may be injected into the optical elements by a light source. The optical elements may guide the light onto corresponding portions of an image pixel array on the image sensor. The image pixels may be used to detect changes in the location, size, and intensity of illuminated portions of the pixel array when the optical elements move due to acceleration of the optical accelerometer. The optical accelerometer may include multiple light pipes having various lengths and thicknesses. Light pipes of matching length and thickness may be formed over opposing sides of a pixel array. The light pipes may be coated with a material that responds to electric or magnetic fields.

Abstract: A tri-axis accelerometer for use in seismic surveying is provided. The accelerometer comprises at least three fiber optic accelerometer elements which have respective fiber sensor coils, and which are characteristic in that the fiber sensor coils are coiled about a common coiling axis and at least one of the accelerometer elements is a slant angle accelerometer element. A corresponding method of manufacturing a tri-axis fiber optic accelerometer is also disclosed. A fiber optic tri-axis accelerometer for sensing acceleration in three directions is also provided, which comprises a first, a second, and a third sensor base, each base including a first, a second, and a third fixed element, respectively, and a first, a second, and a third movable element, respectively, each pair of fixed and movable elements carrying a fiber sensing coil.

Abstract: The invention relates to an apparatus for input of movements and/or registration of forces, comprising at least one light source, at least one position sensitive device (PSD) and at least one diaphragm, wherein at least one of these three elements is moveable with respect to the two other elements. The light source is arranged at a mounting so that light from the light source is emitted through an opening in the mounting and through the at least one diaphragm onto the at least one PSD.

Abstract: A fibre optical accelerometer comprising a base structure, a first seismic mass movably coupled to the base structure through a first hinge element, a second seismic mass movably coupled to the base structure through a second hinge element, an optical fibre coupled to the first and second seismic masses at first and second attachment joints, respectively, to subject the optical fibre to varying strain by displacement of the first and second seismic masses about the first and second hinge structures, respectively.

Abstract: Optical sensors and sensing methods are provided. A particular method includes applying light to a first end of an optical fiber. Light reflected by at least one of a first photonic crystal sensor coupled to a second end of the optical fiber and a second photonic crystal sensor coupled to the second end of the optical fiber is detected. The first photonic crystal sensor exhibits a first reflection spectrum that changes responsive a first sensed parameter and the second photonic crystal sensor exhibits a second reflection spectrum that changes responsive a second sensed parameter. A parameter value of at least one of the first sensed parameter and the second sensed parameter is determined based on the detected light.

Abstract: A plurality of Fabry-Perot interferometric sensors are optically coupled in series with each other to form an ordered optical series. Each Fabry-Perot interferometric sensor has a unique signalband and a passband. Each Fabry-Perot interferometric sensor has its unique signalband within the passbands of all of the next higher ordered Fabry-Perot interferometric sensors in the optical series so that a corresponding unique fringe signal from each of the Fabry-Perot interferometric sensors is a multiplexed output from the optical series.

Abstract: The present disclosure relates generally to an optical signal processor. In one embodiment, the optical signal processor includes a first sub-wavelength grating having a first grating period and a second sub-wavelength grating having a second grating period that is different than the first grating period of the first sub-wavelength grating.

Abstract: A microelectromechanical (MEM) inertial sensor is disclosed which can be used to sense a linear acceleration, or a Coriolis acceleration due to an angular rotation rate, or both. The MEM inertial sensor has a proof mass which is supported on a bridge extending across an opening through a substrate, with the proof mass being balanced on the bridge by a pivot, or suspended from the bridge by the pivot. The proof mass can be oscillated in a tangential direction in the plane of the substrate, with any out-of-plane movement of the proof mass in response to a sensed acceleration being optically detected using transmission gratings located about an outer edge of the proof mass to generate a diffracted light pattern which changes with the out-of-plane movement of the proof mass.

Abstract: The present invention relates to a housing for one or more micromechanical and/or micro-optic components, wherein the housing exhibits a supporting substrate having at least one micromechanical and/or micro-optic component and at least one cap substrate, which is joined to the supporting substrate. The supporting substrate and the at least one cap substrate form at least one cavity, which at least partially encloses the at least one micromechanical and/or micro-optic component, wherein the side of at least one cap substrate facing the at least one micromechanical and/or micro-optic component exhibits at least one optical window and at least one mechanical stop. Furthermore, the object of the present invention is a method for producing such a housing, wherein the method is particularly usable for encapsulation at the wafer level.

Abstract: An optical accelerometer and method of determining an acceleration are disclosed. In one aspect, an accelerometer includes a light source, a substrate, a light guide attached to a first side of the substrate and configured to redirect light from the light source through the substrate. The accelerometer also includes a light detector, a proof mass attached to a second side of the substrate via one or more springs, wherein the second side is opposite the first side and wherein motion of the proof mass alters a characteristic of the light from the light source reaching the light detector, and a processor configured to determine an acceleration based on the characteristic of the light reaching the light detector.

Abstract: There is provided a solid seismic streamer cable for use in seismic surveying in marine environments. The streamer is characterised by a buffer layer 2 which is provided with a cut-out 50 and a sensor element arranged in the cut-out 50. There is also provided an associated hydrophone for integration into the seismic streamer cable. The hydrophone is characteristic in a split-element sensor base 10, 11 being suited for efficient mounting into the cut-outs 50 of the seismic cable. There is also provided an associated accelerometer for integration into the seismic streamer cable. The accelerometer is characteristic by a split-element sensor base 30, 35 for being efficiently arranged into the cut-outs 50 of the seismic cable. A method of producing a seismic streamer cable according to the invention incorporating a hydrophone or accelerometer according to the invention is also provided.

Abstract: An accelerometer assembly and its method of operation. The accelerometer assembly is designed to be very low cost and robust. This enables the accelerometer assembly to be used in traditionally inexpensive consumer products. The accelerometer assembly uses one or more molded elastomeric structures. Each of the elastomeric structures has a flexible neck section and a head section that is supported by the flexible neck section. The head section of the elastomeric structure is placed between a light source and a photodetector. The head section partially obscures the photodetector from the light source. As the elastomeric structure experiences acceleration forces, the neck section flexes and the head section moves. This varies the degree in which the head section obscures the photodetector. The amount of light detected by the photodetector, therefore, becomes a measure of changing acceleration forces.

Abstract: A fibre optic accelerometer particularly intended for use with an interferometer using the compliant cylinder approach but further providing a seismic mass at the core of the cylinder resulting in improved sensitivity and rejection of out-of-axis inputs.

Abstract: A cantilever beam structural resonant-type integrated optical waveguide accelerometer, includes an input waveguide (1), a dissymmetrical structural Mach-Zehnder interferometer (2), a micro-mechanical vibration cantilever beam (3), a short curved waveguide (4) and an output waveguide (5); all the waveguide structures and the cantilever beam use the integrated optical micromachining technique, and the device single-scale integration can be realized by using the temperature-insensitive organic polymer optical waveguide structure and the organic polymer substrate, the key technique indexes such as detection sensitivity, dynamic range are extensively adjusted. The phase difference of the optical signal can be measured by detecting the optical intensity of the resonant frequency of the optical circuit so as to achieve high sensitive acceleration detection, and to be free from the effect of the ambient temperature disturbance and waveguide birefringence.

Abstract: A device for detecting seismic acceleration including a proof mass; a base for providing a sensor acceleration, relative to the proof mass, based on the seismic acceleration; an optical fibre portion operatively connected between the proof mass and the base for providing a fibre tension based on the sensor acceleration, a fibre Fabry-Perot interferometer (FFPI) in the optical fibre portion for providing an optical characteristic representative of the fibre tension, and a compensator for applying a compensating tension to the FFPI to compensate for a change of the optical characteristic due to a temperature change of the FFPI.