Patent classifications
G01B2290/65
Scanning imaging apparatus, method of controlling the same, scanning imaging method, and recording medium
In a scanning imaging apparatus of some aspect examples, a scanner applies an optical scan to a sample to acquire data. A scan controller controls the scanner to sequentially apply, to the sample, pattern scans according to a two-dimensional pattern including cycles. A movement unit relatively moves a scan area corresponding to the two-dimensional pattern and the sample. A movement controller controls the movement unit such that cycles in first and second scans of the pattern scans cross each other. An image constructing unit constructs an image based on data acquired under controls performed by the scan controller and the movement controller. The scan controller and the movement controller perform controls of the scanner and the movement unit respectively such that first and second cycles in a pattern scan cross each other at least at one point.
RAPID EFFECTIVE CASE DEPTH MEASUREMENT OF A METAL COMPONENT USING PHYSICAL SURFACE CONDITIONING
A method for determining an effective case depth of a metal component includes forming a conditioned core surface by blasting or shot peening an exposed surface of the metal component with blast media. The exposed surface is a contiguous exposed surface of the case and core. The method includes measuring surface texture, compressive stresses, or another suitable characteristic of the conditioned core surface using a surface metrology sensor, and identifying a case-core boundary using the measured characteristic, including identifying a location at which a predetermined difference or gradient in the characteristic is present within the exposed surface. The method also includes measuring the effective case depth as a perpendicular distance between a reference surface of the case and the case-core boundary.
METHODS AND SYSTEMS FOR OPTICAL COHERENCE TOMOGRAPHY SCANNING OF CORNEA AND RETINA
An instrument includes: one or more scanning mirrors to receive an OCT sample beam and to scan the sample beam in two orthogonal directions; and an optical system to receive the sample beam and provide the sample beam to an eye. The optical system includes: a first lens having a first focal length, disposed along an optical path from the scanning mirror(s) to the eye at a distance from the cornea which is approximately equal to the first focal length, and a second lens disposed along the optical path between the first lens and the scanning mirror(s). The second lens receives the sample beam from the scanning mirror(s) and provides the sample beam to the first lens as a converging beam such that, as the sample beam is scanned, the sample beam passes through a pivot point located along an optical axis between the eye and the first lens.
METHOD FOR CALIBRATING ONE OR MORE OPTICAL SENSORS OF A LASER MACHINING HEAD, LASER MACHINING HEAD, AND LASER MACHINING SYSTEM
A method for calibrating at least one optical sensor of a laser machining head is provided. The laser machining head comprises a first optical sensor, a deflection device, and a focusing device. A laser beam path of the first optical sensor passes through the deflection device and the focusing device. The method comprises the steps of: deflecting the beam path of the first optical sensor by the deflection device to a first position on a first reference; generating a first optical measurement signal based on measurement light received by the first optical sensor from the first position on the first reference; and determining a correction value for calibrating the first optical sensor based on the first optical measurement signal and according to a deviation of the first position on the first reference from a first target position, which is specified relative to a position of the machining laser beam.
SCAN PATTERN AND SIGNAL PROCESSING FOR OPTICAL COHERENCE TOMOGRAPHY
An OCT system for measuring a retina as part of an eye health monitoring and diagnosis system. The OCT system includes an OCT interferometer, where the interferometer comprises a light source or measurement beam and a scanner for moving the beam on the retina of a patient's eye, and a processor configured to execute instructions to cause the scanner to move the measurement beam on the retina in a scan pattern. The scan pattern is a continuous pattern that includes a plurality of lobes. The measurement beam may be caused to move on the retina by the motion of a mirror that intercepts and redirects the measurement beam. The mirror position may be altered by the application of a drive signal to one or more actuators that respond to the drive signal by rotating the mirror about an axis or axes.
Non-confocal Point-scan Fourier-domain Optical Coherence Tomography Imaging System
A non-confocal point-scan Fourier-domain optical coherence tomography, OCT, imaging system, comprising: a scanning system arranged to perform a two-dimensional point scan of a light beam across an imaging target, and collect light scattered by the imaging target; a light detector arranged to generate a detection signal based on an interference between a reference light and the light collected by the scanning system. The OCT imaging system further comprises hardware arranged to: generate complex volumetric OCT data of the imaging target based on the detection signal, the OCT data including a component which, when the OCT data is processed to generate an enface projection of the OCT data, provides a defocusing and/or distortion in the enface projection; and generate corrected OCT data by executing a correction algorithm which uses phase information in the OCT data to remove at least some of the component from the OCT data.
Interferometry with an achromatic interferometric superposition of electromagnetic fields
An interferometer apparatus includes a beam splitter arranged for splitting an input beam into a first beam propagating along a first interferometer arm including a deflection mirror and a second beam propagating along a second interferometer arm including a deflection mirror. The first and second interferometer arms have an identical optical path length. A beam combiner is arranged for recombining the first and second beams into a constructive output and a destructive output. In the first interferometer arm compared with the second interferometer arm, one additional Fresnel reflection at an optically dense medium is provided and a propagation of the electromagnetic fields of the first and second beams, when recombined by the beam combiner, results in a wavelength-independent phase difference of π between the contributions of the two interferometer arms to the destructive output. Furthermore, an interferometric measurement apparatus and an interferometric measurement method are described.
OPTICAL COHERENCE TOMOGRAPHY APPARATUS, IMAGING METHOD, AND NON-TRANSITORY COMPUTER READABLE MEDIUM STORING IMAGING PROGRAM
An optical coherence tomography apparatus (100) includes a wavelength sweeping laser light source (101), a branching and merging device (103) that branches a light beam emitted from the wavelength sweeping laser light source (101) into an object light beam and a reference light beam, an optical spectrum data generation unit (108) that generates information about wavelength dependence of an intensity difference between a plurality of interference light beams generated by interference between an object light beam scattered from a measurement object (200) and a reference light beam, and a control unit (109) that acquires structural data of the measurement object (200) in a depth direction on the basis of the information about wavelength dependence, and connects a plurality of pieces of structural data in the depth direction acquired at different positions in a scanning direction of the measurement object (200), wherein preliminary measurement is performed by causing the wavelength sweeping laser light source (101) to emit a light beam swept in a wavelength sweep range narrower than a wavelength sweep range in actual measurement, and the actual measurement is performed when it is determined that the measurement object (200) is at a position suitable for performing the actual measurement on the basis of results of the preliminary measurement.
OPTICAL COHERENCE TOMOGRAPHY INSTRUMENT AND ALIGNMENT METHOD
An ophthalmic optical coherence tomography instrument, method, and computer-readable medium. The instrument includes a scanner defining an apparent point source for scanning sample light across a subject position and an objective having a posterior imaging configuration to project the apparent point source onto a pivot point between the objective and the subject position. The objective is settable between the posterior imaging configuration for scanning the sample light across a retina of an eye at the subject position and an anterior imaging configuration for scanning the sample light across a pivot plane. An axial region from which an interferogram is detectable extends across the pivot plane while the objective is in the anterior imaging configuration. A pupil alignment method uses the anterior imaging modality to obtain a structure position of a structure of an eye's anterior segment and then an offset between the structure position and a reference position.
SCAN PATTERN AND SIGNAL PROCESSING FOR OPTICAL COHERENCE TOMOGRAPHY
An OCT system for measuring a retina as part of an eye health monitoring and diagnosis system. The OCT system includes an OCT interferometer, where the interferometer comprises a light source or measurement beam and a scanner for moving the beam on the retina of a patient's eye, and a processor configured to execute instructions to cause the scanner to move the measurement beam on the retina in a scan pattern. The scan pattern is a continuous pattern that includes a plurality of lobes. The measurement beam may be caused to move on the retina by the motion of a mirror that intercepts and redirects the measurement beam. The mirror position may be altered by the application of a drive signal to one or more actuators that respond to the drive signal by rotating the mirror about an axis or axes.