Lumetrics, Inc.

University of Rochester

Lumentrics, Inc.

Filipp V Ignatovich

Michael Alan Marcus

Donald S Gibson

Todd Blalock

Kyle J Hadcock

Christopher T Cotton

David Maxwell Kleinman

Lukas Novotny

A method of identifying the material and determining the physical thickness of each layer in a multilayer structure is disclosed. The method includes measuring the optical thickness of each of the layers of the multilayer object as a function of wavelength of a light source and calculating a normalized group index of refraction dispersion curve for each layer in the multilayer structure. The measured normalized group index of refraction dispersion curves for each of the layers is then compared to a reference database of known materials and the material of each layer is identified. The physical thickness of each layer is then determined from the group index of refraction dispersion curve for the material in each layer and the measured optical thickness data. A method for determining the group index of refraction dispersion curve of a known material, and an apparatus for performing the methods are also disclosed.

Apparatus and method for measurement of multilayer structures

A method of identifying the material and determining the physical thickness of each layer in a multilayer structure is disclosed. The method includes measuring the optical thickness of each of the layers of the multilayer object as a function of wavelength of a light source and calculating a normalized group index of refraction dispersion curve for each layer in the multilayer structure. The measured normalized group index of refraction dispersion curves for each of the layers is then compared to a reference data base of known materials and the material of each layer is identified. The physical thickness of each layer is then determined from the group index of refraction dispersion curve for the material in each layer and the measured optical thickness data. A method for determining the group index of refraction dispersion curve of a known material is also disclosed.

Method of measurement of multilayer structures

An interferometer apparatus which include two or more coupled fiber optic Michelson interferometers using fiber optic stretches which stretch two or more optical fibers wound around the perimeter of the optical fiber stretchers by the same amount is disclosed. Preferably a pair of reference and sample fiber optic stretches are utilized which run in a push-pull mode of operation. When one of the interferometers is a coherent light interferometer it can be used as a reference distance scale for all of the remaining low coherence light interferometer. A method for measuring a physical property of a device under test is also disclosed using the apparatus of the present invention.

Associated interferometers using multi-fiber optic delay lines

An apparatus for measuring the optical performance characteristics and dimensions of an optical element comprising a low coherence interferometer and a Shack-Hartmann wavefront sensor comprising a light source, a plurality of lenslets, and a sensor array is disclosed. The low coherence interferometer is configured to direct a measurement beam along a central axis of the optical element, and to measure the thickness of the center of the optical element. The light source of the Shack-Hartmann wavefront sensor is configured to emit a waveform directed parallel to and surrounding the measurement beam of the interferometer, through the plurality of lenslets, and to the sensor array. A method for measuring the optical performance characteristics and dimensions of a lens using the apparatus is also disclosed.

Apparatus and method for evaluation of optical elements

A portable hand-held camera for imaging the fundus of an eye, the camera comprising a housing comprising an internal cavity terminating at a forward housing end, a forward lens, and a light source configured to direct light from locations distributed around the perimeter of the forward lens forwardly out of the housing end. In other embodiment, a portable hand-held camera for imaging the fundus of an eye includes optics configured to focus light reflected back from the fundus onto an image receptor, with the optics being capable of varying the field of view among differing portions of the fundus. Methods to ensure unique image identification and storage are described.

Portable fundus camera

An apparatus for measuring a layered object comprising a low coherence light source, a coherent light source, and an interferometer including a reference arm and a measurement arm. The reference arm is comprised of a first section of polarization maintaining optical fiber engaged with a first fiber stretcher. The measurement arm is comprised of a second section of polarization maintaining optical fiber engaged with a second fiber stretcher. The first and second fiber stretchers are driven so as to alternatingly vary the lengths of the first section of polarization maintaining optical fiber and the second section of polarization maintaining optical fiber, thereby causing interference signals with the low coherence light when the length of the reference arm is equal to the length of the measurement arm including the distance from the second section of polarization maintaining optical fiber to any of the surfaces of the layers of the object.

Fiber-based interferometric device for measuring axial dimensions of a human eye

An apparatus for measuring the axial length of a human eye, the apparatus comprising a low coherence light source; a beam splitter; a fast displacement module for rapidly varying the path length within a reference arm of an interferometer; a laser directing a laser beam that is co-propagating with light from the low coherence light source into the displacement module.

Apparatus for measurement of the axial length of an eye

Light from a laser source is split into a reference arm and a detection arm. The light in the detection arm is focused into a channel containing particles to be detected and is backscattered by the particles. The light in the reference arm is attenuated. The attenuated and backscattered light are caused to interfere and detected by a split detector so that the effects of background light can be subtracted out, while the backscattered light is detected to detect the particles.

Growing community of inventors

Rochester, NY, United States of America

Filipp V Ignatovich