Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A portable hand-held ocular fundus camera system for imaging the fundus of the eye is disclosed. The camera system is comprised of a camera housing, one or more groups of lens in an internal cavity of the housing, a front group of lenses at the front end of the internal cavity, a contact member to contact at least a portion of the cornea, a light source configured to direct light from locations inside the camera through an annulus near the periphery of the front lens group, so that the light enters the eye through an annulus at the periphery of the pupil of the eye during contact with the cornea. Light from the light source that is reflected off of the fundus that passes through the center portion of the pupil of the eye is imaged onto an imager configured to acquire a sequence of images while an actuator coupled to the imager continuously varies the location of the imager along the optical axis of the camera.

Abstract: 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.