The invention relates to the technical field of grating interferometry, in particular to a Littrow grating interferometry device and a use thereof. The device comprises: a two-frequency orthogonal polarization light source, a polarizing beam splitting prism, a reflection assembly, a detector, and a first diffraction grating and a second diffraction grating having identical parameters. The output light of the two-frequency orthogonal polarization light source is split by the polarizing beam splitting prism into horizontally polarizing measuring light which is transmitted and vertically polarizing measuring light which is reflected. The two beams of measuring light undergo diffraction twice between the first diffraction grating and the second diffraction grating, and finally the two beams of measuring light interfere with each other and are incident on the detector. Grating displacement is calculated according to the interference pattern. The invention achieves secondary diffraction under Littrow incidence, and improves the precision of displacement measurement.

The invention relates to the technical field of grating interferometry, in particular to a Littrow grating interferometry device and a use thereof. The device comprises: a two-frequency orthogonal polarization light source, a polarizing beam splitting prism, a reflection assembly, a detector, and a first diffraction grating and a second diffraction grating having identical parameters. The output light of the two-frequency orthogonal polarization light source is split by the polarizing beam splitting prism into horizontally polarizing measuring light which is transmitted and vertically polarizing measuring light which is reflected. The two beams of measuring light undergo diffraction twice between the first diffraction grating and the second diffraction grating, and finally the two beams of measuring light interfere with each other and are incident on the detector. Grating displacement is calculated according to the interference pattern. The invention achieves secondary diffraction under Littrow incidence, and improves the precision of displacement measurement.

The present invention relates to the field of optics, in particular to a hybrid displacement measuring device, comprising a worktable to be measured, a grating ruler, a laser light source, a first beam splitting mirror, a first measuring assembly, and a second measuring assembly which comprises a first interferometer. A hybrid measuring approach that integrates grating and laser is proposed based on the advantages of the two measuring means. The grating ruler is used to perform long-distance measurement distal to the mirror, and the first interferometer is used to perform short-distance measurement proximal to the mirror, thereby solving the problem that it is difficult to guarantee both the range and the precision of displacement measurement of the worktable to be measured.

A method for operating an optical tomographic imaging apparatus according to the present invention includes: an initial setting step of setting initial positions of a reference mirror and a distal end of an optical part; an imaging step of imaging a biological tubular element after the initial setting step; a reference mirror adjustment step of, after the imaging step, moving the reference mirror to enlarge the image portion of the reflected light from the biological tubular element and the image portion of the reflected light from the tube while reducing an image portion of an artifact caused by reflected light from the optical part, and adjusting the image portion of the artifact to an inside of the image portion of the reflected light from the tube; a magnification adjustment step of, after the reference mirror adjustment step, resetting the image portion of the reflected light from the biological tubular element and the image portion of the reflected light from the tube to a state before the enlargement; and a display step of, after the magnification adjustment step, causing an image display unit to display the image portion of the reflected light from the biological tubular element and the image portion of the reflected light from the tube reset to the state before enlargement.

A workpiece is disposed on a stage in an interferometer. Measurements are taken of the workpiece using the interferometer. An image of a surface of the workpiece is generated from the measurements. Phase error is removed from the image with a neural network operated using the processor. The neural network can be a generative adversarial network.

Systems and methods for improved interferometric imaging are presented. One embodiment is a partial field frequency-domain interferometric imaging system in which a light beam is scanned in two directions across a sample and the light scattered from the object is collected using a spatially resolved detector. The light beam could illuminate a spot, a line or a two-dimensional area on the sample. Additional embodiments with applicability to partial field as well as other types of interferometric systems are also presented.

The present application provides an optical fiber-typed spectral confocal coherence tomography optical system and an application thereof. The system includes an optical fiber coupler, a broadband light source, a reference component, a sample component and a spectrometer. The reference component is connected to a first output end of the optical fiber coupler, for receiving a light source signal emitted by the optical fiber coupler and controllably forming the light source signal into an interference signal. The sample component is connected to a second output end of the optical fiber coupler, for receiving the light source signal emitted by the optical fiber coupler and forming a spectral confocal signal after the light source signal passes through a sample to be tested. The spectrometer is connected to a third output end of the optical fiber coupler.

A light source projects a light beam. An interferometer includes a splitting unit that splits the light beam. The interferometer generates interference beams with the respective split light beams. Each of the interference beam is generated by interference between a measurement beam radiated toward the measurement target and reflected at the measurement beam and a reference beam passing through an optical path. A light-receiving unit receives the interference beams. A processor calculates a distance to the measurement target by associating at least one detected peak with at least one of the spots in accordance with a mirror surface mode or a rough surface mode. The optical path length difference is made different among the split light beams. In the mirror surface mode, the processor uses a distance calculated based on a peak corresponding to a spot for which the optical path length difference is shortest.

A light source projects a light beam. An interferometer includes a splitting unit that splits the light beam. The interferometer generates interference beams with the respective split light beams. Each of the interference beam is generated by interference between a measurement beam radiated toward the measurement target and reflected at the measurement beam and a reference beam passing through an optical path. A light-receiving unit receives the interference beams. A processor calculates a distance to the measurement target by associating at least one detected peak with at least one of the spots in accordance with a mirror surface mode or a rough surface mode. The optical path length difference is made different among the split light beams. In the mirror surface mode, the processor uses a distance calculated based on a peak corresponding to a spot for which the optical path length difference is shortest.

Aspects of the disclosure provide for automated self-inspection by an OCT imaging engine or device, to identify and resolve failures or inefficiencies in the hardware and/or software of the system or device during imaging. An OCT imaging engine can include a catheter connection check system for checking the quality of a physical connection point between a catheter and other components of an OCT imaging device or system. In some examples, the OCT imaging engine includes a self-inspection engine implemented to perform routine self-inspection by using a reference reflector internal to the OCT imaging engine to generate system performance data. The OCT imaging engine can use the system performance data to periodically search for and resolve failures or inefficiencies in the system. The OCT imaging engine can perform a self-calibration process to perform k-linearization and/or correct for chromatic dispersion using mirror measurements collected from an internal reference reflector.