Leland Stanford Junior University

Onur Kilic

Michel J F Digonnet

Olav Solgaard

Gordon S Kino

Onur Can Akkaya

Shrestha Basu Mallick

Michel J Digonnet

Michel Jf Digonnet

Behrad Habib Afshar

Wonuk Jo

Michel JF Digonnet

Kino Gordon S S

A sensor is provided. The sensor includes at least one optical waveguide and an optical reflector. The optical reflector is optically coupled to the at least one optical waveguide and includes a first portion and a second portion. The first portion is configured to reflect a first portion of light back to the at least one optical waveguide. The second portion is configured to reflect a second portion of light back to the at least one optical waveguide. The reflected second portion of the light differs in phase from the reflected first portion of the light by a phase difference that is not substantially equal to an integer multiple of &#x3c0; when the second portion of the optical reflector is in an equilibrium position in absence of the perturbation.

Phase-front-modulation sensor

A sensor is provided, with the sensor including a reflective element and an optical fiber positioned relative to the reflective element such that light emitted from the optical fiber is reflected by the reflective element and propagates in an optical cavity between the optical fiber and the reflective element. A first material is within the optical cavity and has a coefficient of thermal expansion and a thickness that compensate a refractive index change with temperature of a second material within the optical cavity.

Optical-fiber-compatible sensor

Optical apparatus and methods utilizing sensors operating in the reflection mode are provided. The apparatus includes at least one optical bus. The at least one optical bus is configured to be optically coupled to at least one source of input optical signals, to at least one optical detector, and to a plurality of reflective sensing elements. The at least one optical bus transmits an input optical signal from the at least one source to the plurality of reflective sensing elements. At least one reflective sensing element of the plurality of reflective sensing elements receives a portion of the input optical signal and reflects at least a portion of the received portion. The at least one optical bus transmits the reflected portion to the at least one optical detector.

Apparatus and methods utilizing optical sensors operating in the reflection mode

A method for fabricating a sensor is provided, with the sensor including a reflective element and an optical fiber positioned relative to the reflective element such that light emitted from the optical fiber is reflected by the reflective element and propagates in an optical cavity between the optical fiber and the reflective element. The method includes positioning an element within the optical cavity. The element has a coefficient of thermal expansion and a thickness that compensate a refractive index change with temperature of a medium within the optical cavity.

Method of fabricating an optical-fiber-compatible sensor

A gyroscope and a method of detecting rotation are provided. The gyroscope includes a structure configured to be driven to move about a drive axis. The structure is further configured to move about a sense axis in response to a Coriolis force generated by rotation of the structure about a rotational axis while moving about the drive axis. The structure further includes at least one first torsional spring extending generally along the drive axis and at least one second torsional spring extending generally along the sense axis. The gyroscope further includes an optical sensor system configured to optically measure movement of the structure about the sense axis.

Gyroscope utilizing torsional springs and optical sensing

An optical structure includes an optical waveguide and at least one photonic crystal structure. The optical structure also includes a structural portion mechanically coupled to the optical waveguide and the at least one photonic crystal structure such that a region substantially bounded by the structural portion, the optical waveguide, and the at least one photonic crystal structure has a specified volume.

Optical system having a photonic crystal structure and method of fabrication

An acoustic sensor includes a diaphragm having a reflective element. The sensor has an optical fiber positioned relative to the reflective element such that light emitted from the optical fiber is reflected by the reflective element. A first end of the optical fiber and the reflective element form an optical cavity therebetween. The acoustic sensor further includes a structural element mechanically coupled to the diaphragm and the optical fiber. The structural element includes a material having a coefficient of thermal expansion substantially similar to the coefficient of thermal expansion of the optical fiber. For example, the material can be silica.

Optical-fiber-compatible acoustic sensor

A method detects an acceleration. The method includes providing a spatial mode filter positioned such that light emitted from the spatial mode filter is reflected by at least a portion of a reflective surface. The spatial mode filter and the portion of the reflective surface form an optical resonator having an optical resonance with a resonance lineshape. The method further includes emitting light from the spatial mode filter and irradiating the portion of the reflective surface. The portion of the reflective surface is responsive to acceleration of the optical resonator by changing curvature. The method further includes measuring a change of the resonance lineshape due to the acceleration of the optical resonator.

Method of detecting an acceleration

A method detects a topology of a reflective surface. The method includes providing an optical fiber positioned such that light emitted from the optical fiber is reflected by at least a portion of the reflective surface. The optical fiber and the portion of the reflective surface form an optical resonator having an optical resonance with a resonance lineshape. The method further includes emitting light from the optical fiber while the optical fiber is at a plurality of positions along the reflective surface. The light emitted from the optical fiber irradiates a corresponding plurality of portions of the reflective surface. The method further includes measuring a change of the resonance lineshape due to the irradiation of the plurality of portions of the reflective surface.

Method of detecting a topology of a reflective surface

An acoustic sensor includes at least one photonic crystal structure and an optical fiber in optical communication with the at least one photonic crystal structure. The at least one photonic crystal structure has at least one optical resonance with a resonance frequency and a resonance lineshape, wherein at least one of the resonance frequency and the resonance lineshape is responsive to acoustic waves incident upon the acoustic sensor. The acoustic sensor further includes an optical fiber in optical communication with the at least one photonic crystal structure. The optical fiber is configured to transmit light which impinges the at least one photonic crystal structure and to receive at least a portion of the light which impinges the at least one photonic crystal structure.

Acoustic sensor with at least one photonic crystal structure

A gyroscope and a method of detecting rotation are provided. The gyroscope includes a structure configured to be driven to move about a drive axis. The structure is further configured to move about a sense axis in response to a Coriolis force generated by rotation of the structure about a rotational axis while moving about the drive axis. The gyroscope further includes an optical sensor system configured to optically measure movement of the structure about the sense axis. In certain embodiments, the gyroscope is a microelectromechanical system (MEMS) gyroscope.

Gyroscope utilizing MEMS and optical sensing

An optical structure on an optical fiber and a method of fabrication is provided. The optical structure includes an end of an optical fiber and a layer formed on the end of the optical fiber. The layer comprises one or more first portions having a first optical pathlength in a direction perpendicular to the layer and one or more second portions having a second optical pathlength in the direction perpendicular to the layer, the second optical pathlength different from the first optical pathlength.

Optical structure on an optical fiber and method of fabrication

An acoustic sensor includes at least one structure including at least one photonic crystal slab and an optical fiber optically coupled to the at least one photonic crystal slab, and having at least one optical resonance with a resonance frequency and a resonance lineshape. The acoustic sensor further includes a housing mechanically coupled to the at least one structure. At least one of the resonance frequency and the resonance lineshape is responsive to acoustic waves incident upon the housing.

Acoustic sensor with at least one photonic crystal slab

A method utilizes an optical resonator that includes a reflective element and a spatial mode filter positioned relative to the reflective element such that light emitted from the spatial mode filter is reflected by the reflective element. The optical resonator has an optical resonance with a resonance lineshape that is asymmetric as a function of wavelength.

Growing community of inventors

Mountain View, CA, United States of America

Onur Kilic