A fiber-coupled phased-array includes a first photonic integrated circuit (PIC) and a second PIC. The first PIC includes a first set of lenslets and waveguides. The second PIC includes a second set of lenslets and waveguides and is placed at a distance from the first PIC. The optical fibers couple the first PIC to the second PIC and form an interferometric imager that can sample spatial frequencies of a target. Optical delay errors induced by a relative placement of the first PIC and the second PIC are compensated for.

Method and system for calculating a height map of a surface of an object from an image stack in scanning optical 2.5D profiling of the surface by an optical system, a focal plane is scanned at different height positions with respect to the object surface. An image is captured at each height position of the focal plane to form the image stack. The scanning of the focal plane comprises long range sensing and short range sensing a displacement of the focal plane for sensing low and high spatial frequency components. The height position of the focal plane is estimated by combining the low and high spatial frequency components. A height position of each image in the image stack is calculated, based on the estimated height position of each respective focal plane. The images of the image stack are interpolated to equidistant height positions for obtaining a corrected image stack.

A reference signal having a known induced optical delay is used for phase stabilization of optical coherence tomography (OCT) interferograms, and for correcting sampling differences within OCT interferograms, in single mode and multimodal OCT systems. The reference signal can then be used to the measure time shift or sample clock period shifts induced in the interferogram signal by the OCT system. A corresponding OCT interferogram signal can then be corrected to remove the shift induced by the system based on the determination.

A system includes a first optical unit that emits light to a measurement target object and receives first interference light incident from the measurement target object, a second optical unit that emits the light to a reference object configured to have a constant optical path length with respect to a temperature fluctuation and receives second interference light incident from the reference object, a spectroscope connected to the first optical unit and the second optical unit and receives the first interference light and the second interference light to be incident, and a control unit connected to the spectroscope, and the control unit calculates a fluctuation rate of a measurement optical path length with respect to a reference optical path length under a predetermined temperature environment on the basis of the optical path length of the reference object calculated on the basis of the second interference light incident on the spectroscope under the predetermined temperature environment, and the reference optical path length of the reference object acquired in advance, and corrects, on the basis of the fluctuation rate, the optical path length of the measurement target object calculated on the basis of the first interference light incident on the spectroscope under the predetermined temperature environment.

A thickness evaluation method of the cell sheet according to the invention includes tomographically imaging a cell sheet by optical coherence tomography and obtaining a thickness distribution of the cell sheet based on a result of the tomography imaging. A tomographic image corresponding to one cross section of the cell sheet is obtained by tomography imaging while scanning the light in a main scanning direction. The tomography imaging is performed in every time while moving an incident position of the light at a predetermined feed pitch in a sub-scanning direction, thereby a plurality of the tomographic images corresponding to a plurality of cross-sections are obtained. One-dimensional thickness distributions of the cell sheet in the corresponding cross-sections are obtained based on each of the plurality of tomographic images, and a two-dimensional thickness distribution of the cell sheet is obtained by interpolating the one-dimensional thickness distributions.

An optical coherence tomographic device may include a light source, a measurement light generator, a reference light generator, an interference light generator, an interference light detector, and a processor. The interference light detector may include a first and second detector that convert interference light to interference signals, a first signal processing unit that samples the interference signal from the first detector, and a second signal processing unit that samples the interference signal from the second detector. Each of the first and second signal processing units may sample the interference signal at a timing from outside. Light generated by the measurement light generator may at least include first and second correction light. The processor may correct a time lag between sampling timings of the first and second signal processing units by using a first and second correction signal converted from the first and second correction light.

A spatial accuracy correction apparatus performs a spatial accuracy correction of a positioner displacing a displacer to a predetermined set of spatial coordinates using a measurable length value measured by an interferometer and a measurable value of the set of spatial coordinates of the displacement body that is measured by the positioner. The measured length value and the measured value for each measurement point are acquired by displacing the displacement body to a plurality of measurement points in order, one or more repeated measurements are conducted for at least one of the plurality of measurement points being measured after conducting measurement of the measured length value and the measured value for each of the plurality of measurement points, and the plurality of points are measured again when a repeat error of the measured length value is equal to or greater than a threshold value.

A method that corrects an error in positioning in a positioning mechanism by using a measurable length value measured by a laser interferometer and a measured value for spatial coordinates measured by the positioning mechanism. The method includes a measurement step in which a retroreflector affixed to a displacer is displaced to a plurality of measurement points, and the measured length value and the measured value at each of the measurement points is acquired; and a parameter calculation step in which a correction parameter is calculated based on the measured value, the measured length value, and the coordinates of a rotation center of the tracking-type laser interferometer. A first correction constant is applied to the measured length value for each measurement line, and a second correction constant different from the first correction constant is applied to the coordinates of the rotation center of the interferometer for each measurement line.

An optical coherence tomography microscopy apparatus (1) is presented for detecting a three-dimensional image of an optically translucent or reflective sample object (OS), the apparatus comprising an interferometric optical setup including a photo sensor unit (20). A sense signal Si from the photo sensor unit (20) is detected using a detection reference signal. The detection reference signal is derived from a signal indicative for a relative displacement of the sample object (OS) with respect to a reference object.

Method and system for calculating a height map of a surface of an object from an image stack in scanning optical 2.5D profiling of the surface by an optical system, a focal plane is scanned at different height positions with respect to the object surface. An image is captured at each height position of the focal plane to form the image stack. The scanning of the focal plane comprises long range sensing and short range sensing a displacement of the focal plane for sensing low and high spatial frequency components. The height position of the focal plane is estimated by combining the low and high spatial frequency components. A height position of each image in the image stack is calculated, based on the estimated height position of each respective focal plane. The images of the image stack are interpolated to equidistant height positions for obtaining a corrected image stack.