An integrated optical system includes a wavelength tunable optical source and a photonic integrated circuit (PIC). The PIC includes a set of spatial waveguide switches having an input optically coupled to the wavelength tunable optical source and a plurality of outputs. The PIC also includes an optical emitter having a plurality of inputs, each being coupled to a respective one of the plurality of outputs of the set of spatial waveguide switches, the optical emitter configured to produce at an output an optical beam having a wavelength dependent emission direction that changes as light is switched by the set of spatial waveguide switches such that the optical beam may be steered in two dimensions.

The present invention relates to accurately determining a contour of a depolarizing region.

An image processing apparatus extracts a depolarizing region in a polarization-sensitive tomographic image of a subject's eye, and detects, in a tomographic intensity image of the subject's eye, a region corresponding to the extracted depolarizing region. The tomographic intensity image corresponds to the polarization-sensitive tomographic image,

A method for full-field measurement using Doppler imaging, comprising the following steps: turning on a laser and adjusting the laser; adjusting a spatial filter to obtain circular laser spots having uniform intensity distribution; adjusting a quarter-wave plate and a whole polarizer in a system, and requiring two beams in a reference object and a measured object having different frequencies and perpendicular polarization directions; applying slight pressure to the measured object, setting a charge coupled device (CCD) camera into a continuous acquisition mode, observing interference fringes, and adjusting a light path so that the fringes are clear and visible; setting the sampling frequency, sampling time, captured image format and resolution size of the CCD camera; turning on a lithium niobate crystal drive power switch to produce a heterodyne carrier frequency; applying continuous equal pushing force to the measured object by means of piezoelectric ceramics (PZT) so as to make the measured object produce continuous bending deformation; controlling the CCD camera to sample using a computer, and collecting a set of time series light interference images along with the continuous deformation of the measured object; and processing the time series light intensity interference image to obtain a three-dimensional data module comprising continuous deformation of the measured objects distributed in time and space.

A five-degree-of-freedom heterodyne grating interferometry system comprises: a single-frequency laser for emitting single-frequency laser light, the single-frequency laser light can be split into a reference light beam and a measurement light beam; an interferometer lens set and a measurement grating for converting the reference light and the measurement light into a reference interference signal and a measurement interference signal; and multiple optical fiber bundles respectively receiving the measurement interference signal and the reference interference signal, wherein each optical fiber bundle has multiple multi-mode optical fibers respectively receiving interference signals at different positions on the same plane. The system is not over-sensitive to the environment, is small and light, and is easy to arrange. Six-degree-of-freedom ultra-precision measurement can be achieved by arranging multiple five-degree-of-freedom interferometry systems and using redundant information, thereby meeting the needs of a lithography machine worktable for six-degree-of-freedom position and orientation measurement.

An interferometry apparatus comprising: a laser source operable to emit a first light beam; a beam splitter arranged to split the first light beam into an object beam and a reference beam, the object beam passing along an object beam arm and the reference beam passing along a reference beam arm; an adaptive delay line located a distance along the reference beam arm, the adaptive delay line being configured to provide, in use, one or more length-adjusted reference beams; a beam splitter arranged to recombine the object beam from the object beam arm and the length-adjusted reference beam(s) from the reference beam arm; and a photodetector operable to detect interference between the object beam and the length-adjusted reference beam(s).

The invention relates to an assembly comprising a interferometer for carrying out an optical coherence tomography, wherein the interferometer is divided into two spatially spaced-apart interferometer parts (1, 2), wherein the two interferometer parts (1, 2) can be moved related to one another and are optically connected to one another via flexible light guides (3, 4, 5), which bridge the spatial distance, wherein according to the invention, an assembly having an interferometer is provided, which is as unsusceptible as possible to the effects brought about by bending a tube cable packet and allows for an optimum signal-to-noise ratio or an optimum image quality of an OCT image, characterised in that at least one first flexible light guide (3) is designed as a polarisation-maintaining light guide consisting of two connected polarisation-maintaining light-guiding fibres (3a, 3b).

An optical measurement apparatus includes a light source unit generating and outputting light, a polarized light generating unit generating polarized light from the light, an optical system generating a pupil image of a measurement target, using the polarized light, a self-interference generating unit generating multiple beams that are split from the pupil image, and a detecting unit detecting a self-interference image generated by interference of the multiple beams with each other.

A composite measurement system for measuring nanometer displacement is provided. The system includes: a light source, a polarization beam splitting prism, a first phase change module, a second phase change module, a first right-angle prism, a second right-angle prism, a non-polarization beam splitting prism, a scalar interference light collection module, a vector interference light collection module and a displacement calculation module. In the present disclosure, a photodetector is configured to collect an intensity of scalar interference light of the object to be measured being moving, to obtain a periodic light intensity change curve; a CCD camera is configured to collect images of interference vortex light of the object being moving; and the displacement calculation unit is configured to calculate a displacement of the object according to integer periods of the light intensity change curve and angles of image changes of the interference vortex light.

A device and method for measuring a surface of an object, including at least one light source, at least one optical sensor, and an interferometry device having a measurement arm and a reference arm, the former directing light from each light source towards the surface of the object and directing light from the surface towards each optical sensor; the measurement device, in an interferometry configuration, illuminating the reference arm and the measurement arm with each light source and directing the light from the measurement arm and the reference arm towards each optical sensor to form an interference signal; the measurement device, in an imaging configuration illuminating at least the measurement arm and directing the light from the measurement arm towards the optical sensor to form an image of the surface; the measurement device including a digital processor producing, from the interference signal and the image, information on the surface.

A laser interferometer that includes a light source configured to emit laser light, an optical divider configured to divide the laser light into a first optical path and a second optical path, an optical modulator being provided on the first optical path or the second optical path, including an oscillator that oscillates when a current is applied, and being configured to modulate the laser light by using the oscillator, a photoreceptor configured to receive the laser light and output a photoreception signal, the laser light being reflected by an object to be measured that is provided on the first optical path or the second optical path, and a demodulation circuit configured to demodulate, from the photoreception signal, a Doppler signal derived from the object to be measured, based on a reference signal and a modulation signal derived from the optical modulator, wherein Iq/f≤1×10.sup.−7 is satisfied, where an amplitude value of the current applied to the oscillator that is oscillating is Iq [A] and an oscillation frequency of the oscillator is f [Hz].