A system and method is provided for imaging and/or spectroscopy involving generation of a first signal field and a first idler field, illumination of the object with the first idler field, generation of second signal field and a second idler field, combination of the first and second idler fields, such that the two fields are indistinguishable, combination of the first and second signal fields, such that the two fields interfere, first measurement of the interfered signal field by a detection means, one or more additional measurements of the interfered signal field, wherein for each additional measurement a different phase shift is generated in the setup, and wherein all measurements are carried out within the stability time of the setup, and calculation of a phase function.

Embodiments of systems for classifying interference signals are disclosed. In an example, a system for classifying interference signals includes an interferometer including a light source and a detector, and at least one processor. The interferometer is configured to provide a plurality of interference signals each corresponding to a respective one of a plurality of positions on a surface of a semiconductor chip. A spectrum of the light source is greater than a spectrum of white light. The at least one processor is configured to classify the interference signals into a plurality of categories using a model. Each of the categories corresponds to a region having a same material on the surface of the semiconductor chip.

Disclosed is an optical probe system that is capable of high speed, high precision, and high resolution 3D digitalization of engineered objects. The 3D dimensional data of the engineered object is measured using a swept source optical coherence tomography system with improved speed, spatial resolutions, and depth range. Also disclosed is a type of coordinate measurement machine (CMM) that is capable of performing high speed, high resolution, and non-contact measurement of engineered objects. The mechanic stylus in the touch-trigger probe of a conventional CMM is replaced with an optical stylus with reconfigurable diameter and length. The distance from the center of the optical stylus to the measurement probe is optically adjusted to match the height of the object to be measured quickly, which eliminates one dimensional movement of the probe and greatly improves the productivity.

An optical sensor includes an optical fiber inscribed with a repeated refraction pattern such that light scattered from a location on the optical fiber is scattered at multiple frequencies in a range of frequencies. The inscribed patterns overlap at every measurement point along at least a portion of the length of the sensor. An optical sensing system including control circuitry coupled to the optical fiber detects measurement scatter data from the optical fiber over the range of frequencies, determines a change in the detected measurement scatter data over the range of frequencies, and extracts a parameter describing a state of the optical fiber from the determined change in the detected measurement scatter data. The sensor may be made by inscribing a first light refracting pattern on the optical fiber at every measurement point along at least a portion of the length of the sensor and inscribing a second light refracting pattern on the optical fiber that overlaps the first inscribed light refracting pattern at every measurement point along at least that portion of the length of the sensor.

The present invention relates to a method and an assembly for chromatic confocal spectral interferometery, in particular also for spectral domain OCT (SD-OCT) using multi-spectral light. A multiple (e.g. two, three, four, etc.) axial splitting of foci in the interferometric object arm is performed using a multifocal (e.g. bifocal, trifocal, quattro-focal, etc.) optical component, forming thereby at least two, three or even several groups of chromatically split foci in the depth direction. The multifocal optical component is made of a diffractive optical element (712) and a Schwarzschild objective (5). At least two, three, four or even more differently colored foci of different groups of foci coincide in at least one confocal point in the object space of the setup. Thus, at least two, three or even more spectral wavelets are formed in the case of optical scanning of an object measurement point and spectral detection in the wavenumber domain, which wavelets are at least slightly spectrally separated from each other. This results in a significant increase in the optical primary data in the wavenumber domain and reduces the trade-off of the chromatic confocal spectral interferometry between axial measurement range and depth resolution. From the detected data, it is possible to calculate tan (alpha) as the quotient of the absolute phase shift delta_phi and the associated wavenumber difference delta_k, the Fourier transform over the spectral data, in order to respectively determine the optical path difference.

The invention relates to a measuring device for acquiring surface data and/or interfaces of a workpiece to be processed by a laser processing device. The laser processing device comprises a laser source and a processing head which is configured to provide at least one high-energy processing beam, in particular a laser beam. The laser source and the processing head are interconnected by an optical fiber and the measuring device comprises a scanning device configured as an optical coherence tomograph for surface scanning and/or interface scanning of the workpiece. The optical fiber which interconnects the laser source and the processing head forms a component of the scanning device.

Optical Coherence Tomography (OCT) system and apparatus of this instant application is very useful for diagnosis and management of ophthalmic diseases such as retinal diseases and glaucoma etc. Instant innovative OCT diagnostic system leverages advancements in cross technological platforms. The Michelson interferometric system presented in this application could be used for the OCT imaging, which includes biological OCT imaging, medical OCT imaging, ophthalmic OCT imaging, corneal OCT imaging, retinal OCT imaging, and the like. A tunable filter is placed in front of the detector to make the interferometer more sensitive and accurate for examining various samples for diagnosis.

A system and method are described for performing tear film structure measurement. A broadband light source illuminates the tear film. A spectrometer measures respective spectra of reflected light from at least one point of the tear film. A color camera performs large field of view imaging of the tear film, so as to obtain color information for all points of the tear film imaged by the color camera. A processing unit calibrates the camera at the point measured by the spectrometer so that the color obtained by the camera at the point matches the color of the spectrometer at the same point. The processing unit determines, from the color of respective points of the calibrated camera, thicknesses of one or more layers of the tear film at the respective points. Other applications are also described.

An optical distance measurer includes: a beam splitter splitting a laser beam and outputting as measurement light and reference light; a measurement light beam splitter splitting the measurement light and outputting as first measurement light and second measurement light; a reference light beam splitter splitting the reference light and outputting as first reference light and second reference light; a first optical system having a first Rayleigh length, the first optical system emitting the first measurement light to a target object; and a second optical system having a second Rayleigh length different from the first Rayleigh length, the second optical system emitting the second measurement light to the target object; a first receiver receiving the first reference light and first reflection light that is the first measurement light reflected by the target object and outputting a first receiving signal indicating the first reference light and the first reflection light; and a second receiver receiving the second reference light and second reflection light that is the second measurement light reflected by the target object and outputting a second receiving signal indicating the second reference light and the second reflection light.

Disclosed is an OCT system, in particular a mid-IR OCT system, comprising: an upconversion module configured to frequency upconvert light received or receivable by the upconversion module and which is in a wavelength range between a first wavelength and a higher second wavelength, the difference between the second wavelength and the first wavelength being at least 300 nm or larger, and the wavelength range having a center wavelength at 2.8 μm or larger, the center wavelength being defined by the average value between the first wavelength and the second wavelength.