G01B9/02068

Tomographic image capturing device
09989351 · 2018-06-05 · ·

The tomographic image capturing device of the present invention comprises a display means (18) configured to: split light from a light source (11) into measurement light and reference light and cause the measurement light and the reference light to be incident to an object (E) and a reference object (49), respectively; capture tomographic images of the object (E) on the basis of interference light generated by superposition of the measurement light reflected from the object (E) and the reference light reflected from the reference object (49); and display tomographic pictures of the object generated on the basis of the captured tomographic images. The tomographic image capturing device has a first image capturing mode and a second image capturing mode. The first image capturing mode is a mode in which the measurement light is two-dimensionally scanned by raster scan to be incident to the object (E) and the tomographic images of the object (E) are captured. The second image capturing mode is a mode in which the measurement light is two-dimensionally scanned by raster scan to be incident to the object (E) and the tomographic images of the object (E) are captured. The raster scan in the second image capturing mode is thinned from the raster scan in the first image capturing mode. The display means (18) is configured to be switchable between a first display mode and a second display mode. The first display mode is a mode in which a plurality of tomographic pictures including a region of interest of the object (E) is selected from among the tomographic pictures generated on the basis of the tomographic images captured in the second image capturing mode and only the selected plurality of tomographic pictures is displayed. The second display mode is a mode in which all of the tomographic pictures generated on the basis of the tomographic images captured in the second image capturing mode are in turn displayed. The capturing of the tomographic images in the first image capturing mode is performed after separately performing a first adjustment operation and a second adjustment operation for adjustment of an image capturing condition necessary for capturing the tomographic images in the first image capturing mode. The first adjustment operation is based on the tomographic pictures displayed in the first display mode. The second adjustment operation is based on the tomographic pictures displayed in the second display mode.

Method and apparatus for improving image clarity and sensitivity in optical coherence tomography using dynamic feedback to control focal properties and coherence gating

Methods for optical imaging, particularly with optical coherence tomography, using a low coherence light beam reflected from a sample surface and compared to a reference light beam, wherein real time dynamic optical feedback is used to detect the surface position of a tissue sample with respect to a reference point and the necessary delay scan range. The delay is provided by a tilting/rotating mirror actuated by a voltage adjustable galvanometer. An imaging probe apparatus for implementing the method is provided. The probe initially scans along one line until it finds the tissue surface, identifiable as a sharp transition from no signal to a stronger signal. The next time the probe scans the next line it adjusts the waveform depending on the previous scan. An algorithm is disclosed for determining the optimal scan range.

TOMOGRAPHIC IMAGE CAPTURING DEVICE
20170211925 · 2017-07-27 ·

The tomographic image capturing device of the present invention comprises a display means (18) configured to: split light from a light source (11) into measurement light and reference light and cause the measurement light and the reference light to be incident to an object (E) and a reference object (49), respectively; capture tomographic images of the object (E) on the basis of interference light generated by superposition of the measurement light reflected from the object (E) and the reference light reflected from the reference object (49); and display tomographic pictures of the object generated on the basis of the captured tomographic images. The tomographic image capturing device has a first image capturing mode and a second image capturing mode. The first image capturing mode is a mode in which the measurement light is two-dimensionally scanned by raster scan to be incident to the object (E) and the tomographic images of the object (E) are captured. The second image capturing mode is a mode in which the measurement light is two-dimensionally scanned by raster scan to be incident to the object (E) and the tomographic images of the object (E) are captured. The raster scan in the second image capturing mode is thinned from the raster scan in the first image capturing mode. The display means (18) is configured to be switchable between a first display mode and a second display mode. The first display mode is a mode in which a plurality of tomographic pictures including a region of interest of the object (E) is selected from among the tomographic pictures generated on the basis of the tomographic images captured in the second image capturing mode and only the selected plurality of tomographic pictures is displayed. The second display mode is a mode in which all of the tomographic pictures generated on the basis of the tomographic images captured in the second image capturing mode are in turn displayed. The capturing of the tomographic images in the first image capturing mode is performed after separately performing a first adjustment operation and a second adjustment operation for adjustment of an image capturing condition necessary for capturing the tomographic images in the first image capturing mode. The first adjustment operation is based on the tomographic pictures displayed in the first display mode. The second adjustment operation is based on the tomographic pictures displayed in the second display mode.

TEC MODULE HAVING LASER DIODE AS AN INTERFEROMETER LASER BEAM SOURCE IN A LASER TRACKER
20170167845 · 2017-06-15 · ·

Some embodiments of the invention relate to a laser tracker for progressive tracking of a reflective target and for determining the distance to the target having a distance measuring unit, which is designed as an interferometer, for determining a distance change to the target by means of interferometry, a laser beam source for generating measuring radiation for the interferometer, a base, which defines a standing axis, a beam guiding unit for emitting the measuring radiation and for receiving at least a part of the measuring radiation reflected on the target, wherein the beam guiding unit is pivotable by a motor about the standing axis and an inclination axis, which is essentially orthogonal in relation to the standing axis, in relation to the base, and an angle measuring functionality for determining an alignment of the beam guiding unit in relation to the base.

Self calibration for mirror positioning in optical MEMS interferometers

A Micro-Electro-Mechanical System (MEMS) interferometer provides for self-calibration of mirror positioning of a moveable mirror. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS interferometer includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at two or more known positions of the moveable mirror and a calibration module for using the actuator capacitances at the known positions to compensate for any drift in the capacitive sensing circuit.

Self calibration for mirror positioning in optical MEMS interferometers

A Micro-Electro-Mechanical System (MEMS) apparatus provides for self-calibration of mirror positioning of a moveable mirror of an interferometer. At least one mirror in the MEMS apparatus includes a non-planar surface. The moveable mirror is coupled to a MEMS actuator having a variable capacitance. The MEMS apparatus includes a capacitive sensing circuit for determining the capacitance of the MEMS actuator at multiple reference positions of the moveable mirror corresponding to a center burst and one or more secondary bursts of an interferogram produced by the interferometer based on the non-planar surface. A calibration module uses the actuator capacitances at the reference positions to compensate for any drift in the capacitive sensing circuit.

Surface profile measurement method and device used therein

To provide a technique that can measure a surface profile of any test object in a nondestructive manner and noncontact manner, highly accurately, and in a wide tilt angle dynamic range. In white light interference method using a dual beam interferometer, the technique is configured to be capable of changing a surface orientation of a standard plane with respect to an incident optical axis on the standard plane, acquires, while relatively changing the surface orientation of the standard plane with respect to a local surface orientation in any position on a test surface, a plurality of interferograms generated by interference of reflected light from the test surface and reflected light from the standard plane, and calculates the local surface orientation on the test surface from the interferograms to thereby measure a surface profile of the test surface.

Apparatus and methods for detecting optical components and their misalignment in optical coherence tomographic systems

Systems and methods are presented which allow the detection of the presence, type, and misalignment of optical components in the optical train of an optical coherence tomographic instrument to be determined from the use of OCT depth information.