1849 results about "Optical path length" patented technology

The present invention is directed toward a fiber optic position and shape sensing device and the method of use. The device comprises an optical fiber means. The optical fiber means comprises either at least two single core optical fibers or a multicore optical fiber having at least two fiber cores. In either case, the fiber cores are spaced apart such that mode coupling between the fiber cores is minimized. An array of fiber Bragg gratings are disposed within each fiber core. A broadband reference reflector is positioned in an operable relationship to each fiber Bragg grating wherein an optical path length is established for each reflector/grating relationship. A frequency domain reflectometer is positioned in an operable relationship to the optical fiber means. In use, the device is affixed to an object. Strain on the optical fiber is measured and the strain measurements correlated to local bend measurements. Local bend measurements are integrated to determine position or shape of the object.

A photonic crystal optical switch having a periodic dielectric structure including at least one input waveguide. First and second waveguide arms branch from the input waveguide in which the relative optical path lengths of electromagnetic radiation within the arms are controlled by stimuli. At least one output waveguide that combines the electromagnetic radiation propagating within the first and second waveguide arms.

A spectroscopic apparatus which is compact in size and performs high-precision light-splitting with a large angular dispersion. An optical input-processing section outputs a filtered transmitted light, using a bandpass filter that transmits only wavelength bands at one period of an input light, and collects the filtered transmitted light to generate a collected beam. An optic includes a first reflection surface and a second reflection surface which are high but asymmetric in reflectivity, and causes the collected beam incident thereon to undergo multiple reflections within an inner region between the first reflection surface and the second reflection surface, to thereby cause split beams to be emitted via the second reflection surface. A received light-processing section performs received light processing of the beams emitted from the optic. A control section variably controls at least one of a filter characteristic of the bandpass filter and an optical length through the optic.

An integrated optical sensor, using low coherence interferometry, is capable of determining analyte concentration in a material sample based on absorption, scattering and polarization. The sensor includes one or more light collectors, with each collector having a separation distance from the region where the sample is illuminated by the source. The light backscattered from the sample is combined with reference arm light at the same optical path length for each light collector. The intensity of interference may be correlated with the concentration of an analyte in the material, for example the glucose concentration in a turbid medium like skin. The sensor operation can be based on fiber optics technology, integrated optics, or a combination of these. The operation is such that the spectrally resolved scattering and absorption coefficients can be measured simultaneously. In addition, the operation of the sensor can be synchronized with other sensors, for example temperature, pressure, or heartrate.

In part, the invention relates to an image data collection system. The system can include an interferometer having a reference arm that includes a first optical fiber of length of L1 and a sample arm that includes a second optical fiber of length of L2 and a first rotary coupler configured to interface with an optical tomography imaging probe, wherein the rotary coupler is in optical communication with the sample arm. In one embodiment, L2 is greater than about 5 meters. The first optical fiber and the second optical fiber can both be disposed in a common protective sheath. In one embodiment, the system further includes an optical element configured to adjust the optical path length of the reference arm, wherein the optical element is in optical communication with the reference arm and wherein the optical element is transmissive or reflective.

In the three-dimensional display, a two-dimensional display section generates a two-dimensional display image based on an image signal, and a lens array converts the wavefront of the display image light from the two-dimensional display section into a wavefront having a curvature which allows the display image light to focus upon a focal point where an optical path length from an observation point to the focal point is equal to an optical path length from the observation point to a virtual object point, so a viewer can obtain information about an appropriate focal length in addition to information about binocular parallax and a convergence angle. Therefore, consistency between the information about binocular parallax and a convergence angle and the information about an appropriate focal length can be ensured, and a desired stereoscopic image can be perceived without physiological discomfort.

A method and apparatus for three dimensional optical microscopy is disclosed which employs dual opposing objective lenses about a sample and extended incoherent illumination to provide enhanced depth or Z.Iadd.-.Iaddend.direction resolution. In a first embodiment, observed light from both objective lenses are brought into coincidence on an image detector and caused to interfere thereon by optical path length adjustment. In a second embodiment, illuminating light from an extended incoherent light source is detected to the sample through both objective lenses and caused to interfere with a section of the sample by adjusting optical path lengths. Observed light from one objective lens is then recorded. In a third embodiment, which combines the first two embodiments, illuminating light from an extended incoherent light source is directed to the sample through both objective lenses and caused to interfere within a section of the sample by adjusting optical path lengths. The observed light from both lenses is caused to interfere on the image detector by the same optical path length adjustment. .Iadd.In a fourth embodiment of the invention, further spatial structure is introduced into the illumination light. Computational processing is used to enhance lateral or XY resolution as well as depth or Z resolution..Iaddend.

A tunable laser for providing a laser beam with a selectable wavelength. In one example, the tunable laser includes a gain medium for generating the laser beam; a waveguide for processing the laser beam, the waveguide having liquid crystal material or other electro-optic material disposed therein; an optical path length control element disposed within said waveguide for controlling an effective optical path length of the laser cavity; and a wavelength selective element for controlling the wavelength of the laser beam. The tunable laser may be designed without any moving mechanical parts if desired.

Devices, arrangements and apparatus adapted to propagate at least one electro-magnetic radiation are provided. In particular, a probe housing, a sample arm section and a reference arm section can be included. For example, the sample arm section can be at least partially situated within the probe housing, and configured to propagate a first portion of the electro-magnetic radiation that is intended to be forwarded to a sample. The reference arm section can be at least partially situated within the probe housing, and configured to propagate a second portion of the electro-magnetic radiation that is intended to be forwarded to a reference. In addition or as an alternative, an interferometer may be situated within the probe housing. The first and second portions may travel along substantially the same paths, and the electro-magnetic radiation can be generated by a narrowband light source that has a tunable center wavelength. Further, the first and second portions may be at least partially transmitted via at least one optical fiber. A splitting arrangement may be provided which splits the electro-magnetic radiation into the first and second portions, and positioned closer to the sample than to the source of the electro-magnetic radiation, and the first and second portions may be adapted to propagate in different directions. An apparatus may be provided that is configured to control an optical path length of the second portion.

In projection exposure of isolated pattern such as a contact hole, in order to increase the depth of focus a coherence reducing member is disposed on a Fourier transform plane in an image-forming optical path between a mask and a sensitized base, so that coherence is reduced between image-forming beams respectively passing through a plurality of different, concentric regions around the optical axis of the projection optical system on the Fourier transform plane. The coherence reducing member may be a polarization state control member for making a difference in polarization state, a member for making a difference in optical path length, or space filters with different shapes.

Tunable add/drop optical device for injecting or extracting (add/drop) at least a selected optical channel or carrier wavelength in or from a set of multiplexed channels or carriers of different wavelengths comprising a plurality of directional couplers (AD1 . . . AD6) and a plurality of phase-shift stages (SF1 . . . SF5) alternately connected in cascade, wherein each phase-shift stage defines a certain optical path length difference (DELTAL1 . . . DELTAL5) between two distinct optical paths of the stage. The tuning is performed modifying the refraction index of one path of said phase shift stages by means of Joule effect heating strips (L1 . . . L5) or by means of metallic field plates adapted to receive a signal suitable to modify the electric field intensity. The first two phase-shift stages of said plurality of phase-shift stages have differences of length of optical paths different from each other and in a preestablished ratio while the remaining phase-shift stages have differences of length of optical paths identical. It is thus possible to provide a device having an exceptionally flat cross response characteristic, substantially free of ripple due to an inevitable truncation of the Fourier expansion series.

Exemplary embodiments of probes, apparatus, systems and methods can be provided which provide at least one electro-magnetic radiation to at least one sample. For example, a plurality of axicon lenses can be provided which are configured to provide the electro-magnetic radiation(s) having at least partially annulus shape. In addition or alternatively, at least one optical arrangement can be provided which is configured to forward at least one radiation to the sample therethrough having at least partially circularly-symmetric pattern. For example, at least one first portion of the radiation transmitted through a circular section of the pattern can have an optical path-length that is different from an optical path-length of at least one second portion of the radiation transmitted through at least one other section of the pattern.

An organic light emitting device including a first pixel, a second pixel and a third pixel displaying different colors from each other according to the present invention, the organic light emitting device includes a reflecting electrode and a translucent member forming a micro-cavity along with the reflecting electrode, wherein a optical path length is an interval between the reflecting electrode and the translucent member, and wherein the light path lengths of at least two pixels among the first pixel, the second pixel and the third pixel are the same.

A light-emitting optical cavity light-emitting diode device, comprising:

• • a) a substrate;
  • b) a reflective electrode formed over the substrate;
  • c) an unpatterned light-emitting layer formed over the reflective electrode;
  • d) a transparent electrode formed over the unpatterned light-emitting layer;
  • e) one or more different optical spacers, defining at least two different optical path lengths, are formed in different locations over the substrate, between the reflective electrode and the transparent electrode; and
  • f) a low-index layer formed over the transparent electrode.

A method and device are provided for counting cells in a sample of living tissue, such as an embryo. The method involves obtaining a microscopic image of the unstained tissue that reveals cell boundaries, such as a differential interference contrast (DIC) image, and an optical quadrature microscopy (OQM) image which is used to prepare an image of optical path length deviation (OPD) across the cell cluster. The boundaries of individual cells in the cell cluster are modeled as ellipses and used, together with the maximum optical path length deviation of a cell, to calculate ellipsoidal model cells that are subtracted from the OPD image. The process is repeated until the OPD image is depleted of phase signal attributable to cells of the cell cluster, and the cell count is obtained from the number of cells subtracted. The method is capable of accurately and non-invasively counting the number of cells in a living embryo at the 2-30 cell stage, and can be employed to assess the developmental stage and health of human embryos for fertility treatments.

A light-emitting element with which a reduction in power consumption and an improvement in productivity of a display device can be achieved is provided. A technique of manufacturing a display device with high productivity is provided. The light-emitting element includes an electrode having a reflective property, and a first light-emitting layer, a charge generation layer, a second light-emitting layer, and an electrode having a light-transmitting property stacked in this order over the electrode having a reflective property. The optical path length between the electrode having a reflective property and the first light-emitting layer is one-quarter of the peak wavelength of the emission spectrum of the first light-emitting layer. The optical path length between the electrode having a reflective property and the second light-emitting layer is three-quarters of the peak wavelength of the emission spectrum of the second light-emitting layer.

A scanning unit in an image forming apparatus includes a light source, a coupling lens, an aperture, an image forming lens, and a polygon mirror. The light source includes a plurality of surface-emitting lasers. The coupling lens, the aperture, and the image forming lens are arranged on the optical path of light beams emitted by the light source. The polygon mirror deflects light beams of an image formed by the coupling lens towards a photosensitive drum for scanning. The focal length of the image forming lens in a sub-scanning direction is set to be equal to or smaller than an optical path length between the image forming lens and the aperture.

A laser light source includes a light source section for outputting pulse laser light λ₁, λ₂ with a mutually identical repetition frequency, an optical amplification section for amplifying and outputting the pulse laser light λ₁, λ₂ output from the above light source section by means of a common optical amplification medium, an optical demultiplexing section for mutually demultiplexing pulse laser light λ₁, λ₂, an optical multiplexing section for multiplexing and outputting the pulse laser light λ₁, λ₂ demultiplexed in the above optical demultiplexing section, and an optical path length difference setting section for adjusting an optical path length difference between the pulse laser light λ₁, λ₂ in between the optical demultiplexing section and the optical multiplexing section.

The number of pixels of image pickup devices for detecting a focusing status is smaller than the number of pixels of an image pickup device for image-output, or an image pickup size of the image pickup devices for detecting the focusing status is smaller than the image pickup size of the image pickup device for image-output, so that the apparatus for detecting the focusing status that is inexpensive, consumes reduced power, and includes a circuit reduced in size is provided. Two image pickup devices for detecting the focusing status with different optical path lengths are provided with respect to an image pickup device for obtaining an image to be outputted, and subject light intended to be incident on the image pickup device is split to be incident on the image pickup devices for detecting the focusing status. Then, focusing evaluation values are obtained based on video signals from the image pickup devices for detecting the focusing status, and the focusing status is determined to be front focus, rear focus, or in focus based on the magnitudes of the focusing evaluation values. As the image pickup devices for detecting the focusing status, CCDs having less number of pixels and smaller image pickup size than the image pickup device for image-output is used.

A method for enhancing vision of an eye includes a laser delivery system having a laser beam for ablating corneal material from the cornea of the eye. Measurements are made to determine an optical path difference between a plane wave and a wavefront emanating from the retina of the eye for a location at a surface of the cornea. An optical correction is provided to the laser delivery system for the location based on the optical path difference and refractive indices of media through which the wavefront passes. The optical correction includes dividing the optical path difference by a difference between an index of refraction of corneal material and an index of refraction of air. The laser beam is directed to the location on the surface of the cornea and corneal material ablated at the location in response to the optical correction to cause the wavefront to approximate the shape of the plane wave at that location.