Corning Incorporated

Ciba Corning Diagnostics Corp.

Corning Glass Works

Chiron Corporation

Thomas A Cook

Robert Adam Modavis

Rudolf E Slovacek

Walter F Love

Nicholas Francis Borrelli

Evelyn McGee DeLiso

Richard L Schulkind

Irene M Walczak

Vikram Bhatia

Christopher D Robson

Marshall C Hudson

Filter gratings are formed in optical waveguides having photosensitive cores by exposing the cores to actinic radiation in the form of interfering beams having peak intensities that are relatively displaced along an optical axis of the waveguides. Each of the interfering beams has a single-lobed intensity profile and a degree of spatial coherence required to achieve a desired fringe contrast between the two relatively displaced beams. Index modulations in the photosensitive core match the illumination (interference) pattern of the radiation. The relative displacement of the interfering beams reduces side lobes of the gratings' spectral responses by leveling the average refractive index of the index modulations. A second exposure with the two beams but without the beams' interference effects further levels the average refractive index.

Apodization of optical filters with multiple exposures of photosensitive media

A length of oxynitride optical fiber is exposed to actinic radiation that is modulated by an interference technique to form a pattern of refractive index variations that functions as a reflective grating.

Photoinduced grating in oxynitride glass

The invention comprises a spatial filter and a method of spatially filtering a laser beam, particularly a high power laser beam. The inventive spatial filter and method of use is especially suited for use in an optical system for writing index gratings in optical waveguides. The invention provides a method of writing gratings in optical waveguide fiber that results in improved grating performance.

Spatial filter for high power laser beam

A variable period amplitude grating mask for use in making a long period Bragg grating is realized by a helically coiled spring. Stretching or compressing the spring changes the periodicity of the mask. A photosensitive optical waveguide, planar or fiber, is positioned within the spring coils along the major axis of the spring. Actinic radiation is incident on the masked waveguide, and induces an index perturbation in the waveguide having the periodicity of the mask. Different spring coil sizes and/or orientation of the waveguide with respect to the mask provide linear and nonlinear (chirped) grating periods. A device and method are described.

Variable period amplitude grating mask and method for use

An evanescent wave system and method including an optical sensor for use in assaying a reference material and at least one molecular species or analyte in a test medium or test sample for diagnostic and other applicable purposes. The sensor includes a waveguide for propagating a radiation input along its length. The radiation input causes evanescent electromagnetic waves that are capable of stimulating output emissions that are indicative of a reference material and of one or more molecular species or analytes. By comparing the emission(s) indicative of the reference material to the emission indicative of the presence of the molecular species or analyte, the presence and concentration of the molecule in the sample can be determined. The reference material provides for normalization and/or calibration of the system.

Multiple output referencing system for evanescent wave sensor

An optical coupler 10 has two fibers 20, 30 that are adjacent each other in a coupling region 12. One of the fibers has a clad doped with a photosensitive glass, such as germania. The photosensitive glass is exposed to suitable radiation to alter the index of refraction of fiber and tune the coupler 10 to the selected coupling frequency.

Tunable optical coupler using photosensitive glass

Apparatus for forming a refractive index grating in a waveguide in accordance with the invention includes a waveguide formed from a material that changes its index of refraction when exposed to a beam of optical radiation, a source of coherent optical radiation for forming a beam of radiation, a mirror arranged to intercept a first part of a beam and to reflect the first part of the beam through an angle, and a phase delay plate arranged to intercept a second part of the beam for delaying the second part of the beam propagating through the plate, in which the mirror and the phase delay plate are arranged so that the first part of the beam and the second delayed part of the beam form an interference pattern on the waveguide for changing the index of refraction of the waveguide, in a pattern corresponding to the interference pattern for forming an index grating in the waveguide.

Method and apparatus for writing photosensitive grating using Lloyd's

An evanescent wave sensor and method for use in analyzing one or more media, the sensor including a waveguide having first and second wave propagating surfaces. The waveguide propagates an input signal along the waveguide between the first and second surfaces. The first surface receives a first radiation signal which indicates the presence of a first analyte, and the second surface receives a second radiation signal representing one or both of a second analyte and a reference. The first and second surfaces can both be contacted with a single medium, or with two separate media, and one or more output signals can be detected.

Multiple surface evanescent wave sensor with a reference

The present invention relates to a novel evanescent wave sensor which can have a high numerical aperture and is capable of being used in various forms of optically-based assays. Unlike previous fiber optical devices, the present sensors do not use any cladding at the contact points.

Evanescent wave sensors

An assay apparatus employing total internal reflection of excitation radiation at the interface between an optically conductive rod or fiber and a surrounding liquid phase of lower index of refraction. Immobilized on the surface of the fiber is a component of a complex formed in an immunochemical-type reaction; a fluorophore that can be excited into fluorescence by the excitation radiation is attached to another component of the complex. The fiber is coaxially disposed in cantilevered manner within a length of tubing, so that the excitation radiation can be launched into the unsupported end of the fiber and the fluorescent radiation tunneling back into the fiber may be observed at the same fiber end, thereby preventing that portion of the fiber surface between the unsupported fiber end and the mounted end being in contact with other than the surrounding liquid phase.

Immunoassay apparatus

A source of optical wave energy for an optical communication system. One end of an optical waveguide fiber bundle is disposed in light-receiving relationship with respect to light from a Lambertian-type light source such as a light emitting diode. A spherical bead of transparent material disposed between the diode and the fiber bundle endface provides a rugged and inexpensive optical device that tends to collimate the light emitted from the diode.

Growing community of inventors

Corning, NY, United States of America

Thomas A Cook