Abstract:
An apparatus and method for ultrafast real-time optical imaging that can be used for imaging dynamic events such as microfluidics or laser surgery is provided. The apparatus and methods encode spatial information from a sample into a back reflection of a two-dimensional spectral brush that is generated with a two-dimensional disperser and a light source that is mapped in to the time domain with a temporal disperser. The temporal waveform is preferably captured by an optical detector, converted to an electrical signal that is digitized and processed to provide two dimensional and three dimensional images. The produced signals can be optically or electronically amplified. Detection may be improved with correlation matching against a database in the time domain or the spatial domain. Embodiments for endoscopy, microscopy and simultaneous imaging and laser ablation with a single fiber are illustrated.
Abstract:
Some systems described herein include a frequency dependent phase plate for generating multiple phase-contrast images of a sample, each from a different frequency range of light, each phase-contrast image for frequency range of light formed from light diffracted by the sample interfered with undiffracted light that has a frequency-dependent baseline relative phase shift from the phase plate. In some embodiments, the multiple phase-contrast images may be used to generate a quantitative phase image of a sample. The phase-contrast images or the produced quantitative phase image may have sufficient contrast for label-free auto-segmentation of cell bodies and nuclei.
Abstract:
An apparatus and method for ultrafast real-time optical imaging that can be used for imaging dynamic events such as microfluidics or laser surgery is provided. The apparatus and methods encode spatial information from a sample into a back reflection of a two-dimensional spectral brush that is generated with a two-dimensional disperser and a light source that is mapped in to the time domain with a temporal disperser. The temporal waveform is preferably captured by an optical detector, converted to an electrical signal that is digitized and processed to provide two dimensional and three dimensional images. The produced signals can be optically or electronically amplified. Detection may be improved with correlation matching against a database in the time domain or the spatial domain. Embodiments for endoscopy, microscopy and simultaneous imaging and laser ablation with a single fiber are illustrated.
Abstract:
A dual beam assembly is provided for attachment to a chromatic confocal point sensor optical pen. The optical pen provides a single source beam having a measurement range R in the absence of the dual beam assembly. The dual beam assembly includes a first reflective element that is positioned in the source beam and divides it into a first measurement beam and a second measurement beam. The dual beam assembly outputs the first and second measurement beams along first and second measurement axes to different workpiece regions and returns workpiece measurement light arising from the first and second measurement beams back to the optical pen. A second reflective element may be included and configured to deflect the second measurement beam along a desired direction. An offset may be provided between the measuring ranges of the first and second measurement beams.
Abstract:
A method for determining the surface topography of a coated object and for the simultaneous spatially resolved determination of the thickness of the layer on the coated object. It is provided that the surface topography is measured with the aid of white-light interferometry, the thickness of the layer is measured by the principle of reflectometry, and by using, for both measurements, a shared radiation source having an electromagnetic radiation spectrum, which is reflected from the layer surface in a first wavelength range contained in the radiation spectrum and which penetrates into the layer in a second wavelength range contained in the radiation spectrum. Also described is a corresponding optical measuring instrument. The method and the optical measuring instrument make simultaneous highly accurate surface measurement of the surface topography and of the layer thickness of coated objects possible.
Abstract:
An apparatus and method for ultrafast real-time optical imaging that can be used for imaging dynamic events such as microfluidics or laser surgery is provided. The apparatus and methods encode spatial information from a sample into a back reflection of a two-dimensional spectral brush that is generated with a two-dimensional disperser and a light source that is mapped in to the time domain with a temporal disperser. The temporal waveform is preferably captured by an optical detector, converted to an electrical signal that is digitized and processed to provide two dimensional and three dimensional images. The produced signals can be optically or electronically amplified. Detection may be improved with correlation matching against a database in the time domain or the spatial domain. Embodiments for endoscopy, microscopy and simultaneous imaging and laser ablation with a single fiber are illustrated.
Abstract:
Low-coherence interferometric apparatus for light-optical scanning of an object (18) with a low-coherence interferometer (6) comprising a low-coherent light source (7), a reference reflector (21) and a detector (25), wherein light emitted by the light source (7) is split into two optical paths (11,12), a first fraction of the light being irradiated as measurement light (16) onto the object and a second fraction of the light being irradiated as reference light (22) upon the reference reflector (21), and wherein, after reflection on the object (18) or the reference reflector (21) respectively, the measurement light (16) and the reference light (22) are combined at a beam junction (10) in such a manner that an interference signal which contains information about the reflection intensity of the measurement light, relative to the respective scan position is generated.In order to enable a very fast scan, a variable wavelength selection device (30) is positioned in the light path of the detection light between the beam junction (10) and the detector (25). A wavelength-dependent selection of the detection light (24) is performed by this device in such a manner that the detector (25) selectively receives preferentially light with wavelengths which correspond to a predetermined sequence of wavenumbers k. For varying the scan position along the scan path (27) different sequences of wavenumbers k can be set.
Abstract:
An apparatus for performing high speed scanning of an optical delay and its application for performing optical interferometry, ranging, and imaging, including cross sectional imaging using optical coherence tomography, is disclosed. The apparatus achieves optical delay scanning by using diffractive optical elements in conjunction with imaging optics. In one embodiment a diffraction grating disperses an optical beam into different spectral frequency or wavelength components which are collimated by a lens. A mirror is placed one focal length away from the lens and the alteration of the grating groove density, the grating input angle, the grating output angle, and/or the mirror tilt produce a change in optical group and phase delay. This apparatus permits the optical group and phase delay to be scanned by scanning the angle of the mirror. In other embodiments, this device permits optical delay scanning without the use of moving parts.
Abstract:
An apparatus comprising: a double path interferometer comprising a sample path for an object and a reference path; a source of linearly polarized light for the double path interferometer, a phase plate positioned in the sample path; means for superposing the sample path and reference path to create a beam of light for detection; means for spatially modulating the beam of light to produce a modulated beam of light; means for dispersing the modulated beam of light to produce a spatially modulated and dispersed beam of light; a first detector; a second detector, and means for splitting the spatially modulated and dispersed beam of light, wherein light of a first linear polarization is directed to the first detector and light of a second linear polarization, orthogonal to the first linear polarization, is directed to the second detector.
Abstract:
A broadband interferometry for a measurement range extension beyond a coherence length of a light source includes a wavelength tunable laser as the light source outputting a coherence wavelength beam; and an interferometer disposed between the wavelength tunable laser and a target to be measured and including a reference arm, a measurement arm and a device combining a reference beam and measurement mean to produce a combined interference beam, wherein a local oscillation of the reference beam is replicated by a cavity multiplication or cascading optical delayed lines with a fiber optic cavity, and quantifiable optical properties including a wavelength group delay, a chromatic dispersion, a polarization mode dispersion and a model dispersion are inserted into the local oscillation of the reference beam to incrementally quantify the replicated copies of the local oscillation as the number of the delayed copies of the local oscillation increase for extension of a measurement rage to the target.