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 wavelength-swept light source projects a light beam. An interferometer includes a splitting unit that splits the light beam projected from the wavelength-swept light source into light beams radiated toward a plurality of spots on a measurement target. 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 that is at least partially different from an optical path of the measurement beam. A light-receiving unit receives the interference beams from the interferometer. A processor calculates distance to the measurement target by associating a detected peak of the interference beams with one of the spots. The optical path length difference between the measurement target and the reference beam is made different among the light beams split in correspondence with the plurality of spots.

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 of a self-mixed interferometer (SMI) emits infrared light. The infrared light is directed to an eyebox location with the scanning module by scanning the infrared light into a waveguide. Feedback infrared light is measured by a light sensor of the SMI.

According to one embodiment, a registration mark includes a first step portion and a second step portion. The first step portion includes a plurality of first steps which descend step by step in a first direction from a surface of a substrate or a layer formed on the substrate. The second step portion includes a plurality of second steps which descend step by step from the surface in a second direction different from the first direction and have the same number as the number of the plurality of first steps, is spaced apart from the first step portion, and is disposed rotationally symmetrically to the first step portion.

An optical interferometric system for measurement of a full-field thickness of a plate-like object in real time includes two light sources, two screens, two image capturing devices, and an image processing module. The light sources radiate incident lights toward a reference point on the plate-like object in respective directions to produce respective interference fringe patterns (IFPs). The image capturing devices capture light intensity distribution images respectively of the IFPS imaged respectively on the screens. The image processing module calculates a fringe order at the reference point according to the light intensity distribution images, and obtains a full-field thickness distribution of the plate-like object according to the fringe order.

Optical coherence tomography (OCT) apparatuses and methods include a first electro-magnetic radiation (EMR) source providing EMR to a first optical path associated with a sample and a second optical path associated with a reference. A multi-beam generator unit (MBGU) generates first and second EMR beams having different wavelength contents. A scanning system illuminates the sample with the first and second EMR beams, at a first and second time, at a first and second location. An interference module generates interference signals based on received EMR returning from the reference and the first and second EMR beams returning from the sample. A detector generates detection signals based on received interference signals and a processor generates OCT data based on the processed detection signals. In some embodiments, three EMR beams having different wavelength contents with linearly independent vectors illuminate at least one same location of the sample.

An atomic force microscope (“AFM”) based interferometer, uses a light source, and a splitting optical interface, splitting the light beam into a signal light beam and a reference light beam. Both the signal and reference light beams are focused in the vicinity of an AFM cantilever. A beam displacer introduces a lateral displacement between the signal light beam and reference light beam, the lateral displacement being such that, in at least one plane between the beam displacer and the focusing lens structure, the center of the signal light beam is separated from the center of the reference light beam by more than half a sum of their beam diameters on that plane. A detector operates to determine differences in optical path length between the signal light beam and reference light beam to determine information about movement of the cantilever.

An interferometry system including a first telescope for simultaneously receiving a first optical/infrared signal and a first radio signal from a target; a second telescope configured to simultaneously receive a second optical/infrared signal and a second radio signal from the target; a first beam splitter communicatively connected to the first telescope, where the first beam splitter is configured to separate the first optical/infrared signal from the first radio signal; a second beam splitter communicatively connected to the second telescope, where the second beam splitter is configured to separate the second optical/infrared signal from the second radio; and a first optical/infrared interferometer configured to detect an interferometry image of the target using the first and second optical/infrared and radio signals.

In a system for analyzing optical properties of an object (350) a point source of light (100) composed of multiple spectral bands each having a respective amplitude, phase and polarization is converted by first optics (120, 150) into a line light source to illuminate an object line on the object. A beam splitter (200) splits the light exiting the first optics and directs a first portion of light on to the object (350) as an illuminated line and a second portion of the light on to a reference mirror (450). Second optics (500) collects respective first and second lines of light reflected by the object and mirror of and collinearly images the reflected lines of light as an image line on to an imaging spectrometer (550) wherein mutual interference allows determination of the optical properties of the object at each point along the object line.