Abstract: A method of calculating an aerial image of a spatial light modulator array includes calculating pair-wise interference between pixels of the spatial light modulator array; calculating effective graytones corresponding to modulation states of the pixels; and calculating the aerial image based on the pair-wise interference and the effective graytones. The graytones depend only on the modulation states of the pixels. The pair-wise interference depends only on position variables. The position variables are position in an image plane and position in a plane of a source of electromagnetic radiation. The pair-wise interference can be represented by a matrix of functions. The pair-wise interference can be represented by a four dimensional matrix. The effective graytones are approximated using sinc functions, or using polynomial functions.

Abstract: Tomographic images of a plurality of planes at a disease site of a fundus are taken exactly within a short period of time, and the tomographic images are respectively displayed so that the positional relationship thereof becomes clear. A low coherent optical tomographic image sensing apparatus for imaging a fundus includes a sensing unit which takes tomographic images of a plurality of planes intersecting each other in time division, a display unit which displays the taken tomographic images at separate sites on the identical screen, and a position indication unit which displays, in each tomographic image, an intersection position of the each tomographic image and another tomographic image intersecting each other.

Abstract: Methods and computer program products for quantitative three-dimensional (“3D”) image correction in optical coherence tomography. Using the methods and computer program products, index interface (refracting) surfaces from the raw optical coherence tomography (“OCT”) dataset from an OCT system can be segmented. Normal vectors or partial derivatives of the curvature at a refracting surface can be calculated to obtain a refracted image voxel. A new position of each desired refracted image voxel can be iteratively computed. New refracted corrected voxel positions to an even sampling grid can be interpolated to provide corrected image data. In some embodiments, clinical outputs from the corrected image data can be computed.

Abstract: In one aspect, the invention relates to a method of acquiring optical coherence tomographic data from a sample. The method includes the steps of scanning a first location on the sample to obtain a first set of optical coherence tomographic data, scanning a second location on the sample to obtain a second set of optical coherence tomographic data, and defining a fiducial position relative to a location on the sample using one of the two sets of optical coherence tomographic data. In one embodiment, the first set of optical coherence tomographic data is survey data. However, in another embodiment the first set of optical coherence tomographic data is sample measurement data.

Abstract: An apparatus for measuring the axial length of a human eye, the apparatus comprising a low coherence light source; a beam splitter; a fast displacement module for rapidly varying the path length within a reference arm of an interferometer; a laser directing a laser beam that is co-propagating with light from the low coherence light source into the displacement module.

Abstract: An optical coherence tomographic analysis system for analyzing a pharmaceutical delivery system comprising manufacturing means for manufacturing the pharmaceutical delivery system, the manufacturing means including at least one manufacturing process, and an optical coherence tomographic system having a light source that is adapted to direct a radiation beam to the pharmaceutical delivery system, whereby the radiation beam interacts with the pharmaceutical delivery system, the interaction including the emission of emitted light by the pharmaceutical delivery system, the interferometer being adapted to receive the emitted light from the pharmaceutical delivery system and construct an optical image of the pharmaceutical delivery system from the emitted light in real-time during manufacturing of the pharmaceutical delivery system.

Abstract: In an optical tomographic imaging apparatus, a wavelength of a light beam emitted from the light source is selected by a light source section filter, and the light beam emitted from the light source is split into a measurement light beam and a reference light beam. The measurement light beam is reflected from a measurement subject when the measurement light beam is irradiated, is amplified. A specific wavelength from the amplified reflected light beam is selected by an amplifying section filtering mechanism having a filter characteristic identical to a time variation characteristic of the light source section filter, and then the reflected light beam is multiplexed with the reference light beam. A tomographic image of the measurement subject is acquired from detection result of an interference light beam between the reflected light beam and the reference light beam which have been multiplexed.

Abstract: An apparatus has an optical system detecting spectral information and having an optical scanner and a driving unit changing the optical path length by moving an optical member, a monitor, a control unit obtaining a tomographic image by performing Fourier analysis on the information and displaying the obtained image, and a unit previously setting an image on the monitor, in which the member is moved from an initial position and presence or absence of the tomographic image is determined, when the presence is detected, whether the tomographic image is normal or inverted is determined, and when the tomographic image is not the set image, the member is moved to obtain the set image, and when the tomographic image is the set image, the member is moved so that a position of the tomographic image in the depth direction coincides with a predetermined adjustment position and the driving unit is stopped.

Abstract: A method and device for detecting the contour data and/or optical characteristics of an object, such as a tooth or a tooth restoration, based on an interference and/or autocorrelation measurement using an image sensor. To permit an exact surface detection in addition to a determination of the optical characteristics of the object, individual light beams strike the object, which are located at a distance from one another in such a way that no impact of reflected individual light beams takes place on immediately adjacent pixels of the image sensor.

Abstract: A method and an apparatus are disclosed for scatterfield microscopical measurement. The method integrates a scatterometer and a bright-field microscope for enabling the measurement precision to be better than the optical diffraction limit. With the aforesaid method and apparatus, a detection beam is generated by performing a process on a uniform light using an LCoS (liquid crystal on silicon) or a DMD (digital micro-mirror device) which is to directed to image on the back focal plane of an object to be measured, and then scattered beams resulting from the detection beam on the object's surface are focused on a plane to form an optical signal which is to be detected by an array-type detection device. The detection beam can be oriented by the modulation device to illuminate on the object at a number of different angles, by which zero order or higher order diffraction intensities at different positions of the plane at different incident angles can be collected.

Abstract: Apparatus and method for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source is split into N spectral bands. The N spectral bands are individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band is detected by a separate photo detector and amplified. For each spectral band the signal is band pass filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is reduced by a factor equal to the number of spectral bands. The signal remains the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

Abstract: An imaging apparatus that captures a tomographic image of a subject includes: a first tomographic image acquisition unit to acquire a first tomographic image of the subject, a tomographic image analysis unit to analyze the first tomographic image, an image capturing parameter setting unit to set an image capturing parameter for capturing a second tomographic image of the subject according to a result of analysis by the tomographic image analysis unit, a second tomographic image acquisition unit to acquire the second tomographic image captured according to the image capturing parameter set by the image capturing parameter setting unit, and a correction unit to correct positional deviation of the first tomographic image by using the second tomographic image.

Abstract: Deterioration of the resolution of tomographic images obtained by optical tomography measurement is prevented. Interference signals, which are obtained when a light beam L is emitted, are divided into a plurality of divided interference signals each having different wavelength bands. Spectral analysis is administered for each of the plurality of divided interference signals, to obtain a plurality of pieces of intermediate tomographic data. The plurality of pieces of intermediate tomographic data are employed to obtain tomographic data, a tomographic image is generated based on the tomographic data, then displayed.

Abstract: Sinusoidal in-phase and in-quadrature signals at a given spatial frequency are combined with the irradiance signals generating a correlogram of interest and integrated over the length of the correlogram data-acquisition scan. The integration outputs are then used to calculate the amplitude and the phase of the correlogram signal at the selected spatial frequency, thereby producing targeted spectral information. The signal generator used to generate the in-phase and in-quadrature sinusoidal signals may be scanned advantageously through any desired range of spatial frequencies, thereby producing corresponding amplitude and phase spectral information for the correlogram. Because the procedure produces spectral information independently of the number of data frames acquired during the interferometric scan, it is materially more rapid than conventional FFT analysis.

Abstract: Systems, arrangements and methods for obtaining three-dimensional imaging data are provided. For example, a broadband light source can provide a particular radiation. A first electro-magnetic radiation can be focused and diffracted, and then provided to at least one sample to generate a spectrally-encoded line. A second electro-magnetic radiation may be provided to a reference, which may include a double-pass rapidly-scanning optical delay, where the first and second electro-magnetic radiations can be based on the particular radiation. An interference between a third electro-magnetic radiation (associated with the first electro-magnetic radiation) and a fourth electro-magnetic radiation (associated with the second electro-magnetic radiation) can be detected. The spectrally-encoded line may be scanned over the sample in a direction approximately perpendicular to the line. Image data containing three-dimensional information can then be obtained based on the interference.

Abstract: An optical interference apparatus for carrying out Fourier domain optical coherence tomography. Multiple beams are provided and respective interferograms are recorded simultaneously for a plurality of different focal depths within a substance to be examined. Combined images are derived from the interferograms for a plurality of different focal depths, whereby a single image may be constructed with an increased depth of field. The axial spacing of the foci is calculated to take into account the Rayleigh range of the focal waist in the substance to be examined.

Abstract: A dimension measuring apparatus includes a light beam splitting element for splitting light emitted from a white light source into measuring light flux and reference light flux, a reference light scanning optics for varying optical path length of the reference light flux, a detector for detecting interference signal produced by the light fluxes, and a controller for determining the surface height of the object from the optical path length of the reference light flux corresponding to maximum value of the interference signal. The reference light scanning optics includes a rotary member, first and second reflective elements disposed to be symmetrical with respect to the rotation axis of the rotary member, and light beam deflecting members that direct the reference light flux to be incident on the first reflective element along the direction parallel and opposite to the incident direction of the reference light flux on the second reflective element.

Abstract: A vibration-resistant interferometric scanning system and method are provided in the present invention. In the present invention, the brightness distribution in a high-coherence interference pattern is analyzed so as to perform a compensation action to lock the brightness distribution of a high-coherence interference pattern and consequently locking the fringe distribution of a low-coherence interference pattern or to perform a scanning operation composed of plural shifting actions with specified scanning distances in sequence and plural compensation actions to lock the fringe distribution in a low-coherence interference pattern corresponding to the surface profile of a measured object. Consequently, with the system and method of the present invention, the surface profile of a measured object disturbed by external or internal vibrations can be measured accurately and precisely.

Abstract: An OCT measurement apparatus includes a level detection section which detects the signal level of a piece of signal intensity information in interference information outputted from an interference beam detection section, a variable optical attenuator (VOA) which adjusts the light quantity of a return beam of a reference beam, and a light quantity control section which controls the VOA on the basis of the signal level of the piece of signal intensity information in the interference information detected by the level detection section. Accordingly, an interference signal at an appropriate level can be detected without saturation of the interference signal and reduction of an S/N ratio, and optical structure information of an object to be measured can be generated using the interference signal.

Abstract: Interferometers and autocorrelator based sensors are disclosed that are configured to have multiple sample arms which can be scanned and the backscattered low coherence source light from a sample resolved in a single sweep of one or more variable delays of the sensor. Borescopes and catheters capable of scanning multiple sections or areas of materials and tissues using these sensors are described.

Abstract: A light control unit that combines and outputs a plurality of light beams, including: a light emission section capable of outputting three or more light beams swept in wavelength within different wavelength ranges from each other; a wavelength combining section having wavelength selectivity, that combines and outputs at least two of the three or more light beams; and a control section that performs control in the light emission section, or upstream or downstream of the wavelength combining section in the optical path of the light beams to cause at least one light beam is outputted during a time period which is different from a time period in which another one or more light beams are outputted, thereby two or more light beams having different wavelengths from each other are combined and outputted at the same time.

Abstract: An apparatus and method are provided. In particular, at least one first electro-magnetic radiation may be provided to a sample and at least one second electro-magnetic radiation can be provided to a non-reflective reference. A frequency of the first and/or second radiations varies over time. An interference is detected between at least one third radiation associated with the first radiation and at least one fourth radiation associated with the second radiation. Alternatively, the first electro-magnetic radiation and/or second electro-magnetic radiation have a spectrum which changes over time. The spectrum may contain multiple frequencies at a particular time. In addition, it is possible to detect the interference signal between the third radiation and the fourth radiation in a first polarization state. Further, it may be preferable to detect a further interference signal between the third and fourth radiations in a second polarization state which is different from the first polarization state.

Abstract: An ophthalmic surgical microscope (100) has a microscope main objective (101) and a viewing beam path (105) which passes through the microscope main objective (101) for visualizing an object region. The ophthalmic surgical microscope (100) includes an OCT-system (140) for recording images of the object region (108). The OCT-system (140) includes an OCT-scanning beam (142) which is guided via a scan mirror arrangement (146) to the object region (108). An optic element (147) is provided between the scan mirror arrangement (146) and the microscope main objective (101). This optic element (147) bundles the OCT-scanning radiation exiting from the scan mirror arrangement (146) and transfers the same into a beam path which passes through the microscope main objective (101). Alternatively or in addition, the ophthalmic surgical microscope (100) includes an opthalmoscopic magnifier lens (132) which can be pivoted into and out of the viewing beam path (105) and the OCT-scanning beam (142).

Abstract: Some embodiments of the present invention provide optical coherence tomography systems including an OCT engine and a processor. The OCT engine is configured to provide both standard OCT imaging and spectral domain phase microscopy (SDPM) imaging. The processor is coupled to the OCT engine and is configured to use a first signal processing method when the OCT engine is configured to provide standard OCT imaging and a second signal processing method when the OCT engine is configured to provide SDPM imaging. Related methods and computer program products are also provided.

Abstract: In one aspect, the invention relates to an imaging probe. The imaging probe includes an elongate body having a proximal end and distal end, the elongate body adapted to enclose a portion of a slidable optical fiber, the optical fiber having a longitudinal axis; and a first optical assembly attached to a distal end of the fiber. The first optical assembly includes a beam director adapted to direct light emitted from the fiber to a plane at a predetermined angle to the longitudinal axis, a linear actuator disposed at the proximal portion of the elongated body, the actuator adapted to affect relative linear motion between the elongate body and the optical fiber; and a second optical assembly located at the distal portion of the elongate body and attached thereto, the second optical assembly comprising a reflector in optical communication with the first optical assembly, the reflector adapted to direct the light to a position distal to the elongate body.

Abstract: An ophthalmic surgical microscope (100) has a microscope main objective (101) and a viewing beam path (105) which passes through the microscope main objective (101) for visualizing an object region. The ophthalmic surgical microscope (100) includes an OCT-system (140) for recording images of the object region (108). The OCT-system (140) includes an OCT-scanning beam (142) which is guided via a scan mirror arrangement (146) to the object region (108). An optic element (147) is provided between the scan mirror arrangement (146) and the microscope main objective (101). This optic element (147) bundles the OCT-scanning radiation exiting from the scan mirror arrangement (146) and transfers the same into a beam path which passes through the microscope main objective (101). Alternatively or in addition, the ophthalmic surgical microscope (100) includes an opthalmoscopic magnifier lens (132) which can be pivoted into and out of the viewing beam path (105) and the OCT-scanning beam (142).

Abstract: The invention relates to a method and device for measuring an object for measurement, comprising at least one reference structure for the definition of an object coordinate system, fixed with relation to the object, by means of a measuring system, which comprises at least one sensor system for recording a contour of the object for measuring in a measurement coordinate system. According to the invention, the object for measurement is placed in a measuring position in the recording region of the sensor system, the position of the object coordinate system is fixed by means of the reference structure, the object coordinate system is linked to the measurement coordinate system, the sensor system is turned about a rotation axis relative to the object for measurement, in order to determine contour data and a processing of the contour data carried out in an analytical unit, taking into account the position of the object coordinate system. The invention further relates to an application for contour determination.

Abstract: A short coherence interferometer apparatus for measuring multiple axially spaced regions of a specimen, in particular the eye, which has at least one measuring beam path, through which multiple individual measuring beams are incident on the specimen, and one reference beam path, through which a reference beam runs, with which the individual measuring beams are superimposed and brought into interference. The individual measuring beams are axially offset to one another upon incidence on the specimen by an amount which is adapted to the axial spacing. The interferometer apparatus superimposes each individual measuring beam with the reference beam in an interfering manner and conducts it to a detector associated with the particular individual measuring beam. The individual measuring beams are combined into a mixture in which they have varying phasing in the superposition with the reference beam.

Abstract: In general, in one aspect, the invention features a method that includes using an optical coherence tomography system to acquire a plurality of frames of a sample where each frame includes optical information about the composition of the sample through a section of the sample. The method further includes averaging over two or more of the frames to provide an image of the section of the sample where successive frames of the two or more frames are acquired with a time lapse of 0.05-0.7 seconds. Embodiments of the method may have unique advantages for endoscopic subcellular imaging. For example, they can enable subcellular imaging with low-NA optics (e.g., NA=0.25 or less) while providing morphological imaging of the underlying tissue up to 0.6 mm without focal tracking.

Abstract: The present invention relates to near-field scanning optical microscopy (NSOM) and near-field/far-field scanning microscopy methods, systems and devices that permit the imaging of biological samples, including biological samples or structures that are smaller than the wavelength of light. In one embodiment, the present invention permits the production of multi-spectral, polarimetric, near-field microscopy systems that can achieve a spatial resolution of less than 100 nanometers. In another embodiment, the present invention permits the production of a multifunctional, multi-spectral, polarimetric, near-field/far-field microscopy that can achieve enhanced sub-surface and in-depth imaging of biological samples. In still another embodiment, the present invention relates to the use of polar molecules as new optical contrast agents for imaging applications (e.g., cancer detection).

Abstract: A method including: imaging test light emerging from a test object over a range of angles to interfere with reference light on a detector, wherein the test and reference light are derived from a common source; for each of the angles, simultaneously varying an optical path length difference from the source to the detector between interfering portions of the test and reference light at a rate that depends on the angle at which the test light emerges from the test object; and determining an angle-dependence of an optical property of the test object based on the interference between the test and reference light as the optical path length difference is varied for each of the angles.

Abstract: Image quality of tomographic images obtained by optical tomographic measurement is improved. Spatial frequency processes are administered on a tomographic image, with the frequency processing properties (high frequency gain) in the scanning direction of a measuring light beam set to be lower than the frequency processing properties (high frequency gain) in the direction of the optical axis of the measuring light beam. For example, a smoothing process that removes high frequency components is administered to the tomographic image only in the scanning direction. Alternatively, a sharpening process that emphasizes high frequency components is administered to the tomographic image only in the direction of the optical axis.

Abstract: An image data set acquired by an optical coherence tomography (OCT) system is corrected for effects due to motion of the sample. A first set of A-scans is acquired within a time short enough to avoid any significant motion of the sample. A second more extensive set of A-scans is acquired over an overlapping region on the sample. Significant sample motion may occur during acquisition of the second set. A-scans from the first set are matched with A-scans from the second set, based on similarity between the longitudinal optical scattering profiles they contain. Such matched pairs of A-scans are likely to correspond to the same region in the sample. Comparison of the OCT scanner coordinates that produced each A-scan in a matching pair, in conjunction with any shift in the longitudinal scattering profiles between the pair of A-scans, reveals the displacement of the sample between acquisition of the first and second A-scans in the pair.

Abstract: An image sensor 20A contains a photodiode array portion 21, a signal processor 22, a switching instruction part 23A and a control part 24A. Each switch SWn is provided between the corresponding photodiode PDn and the common output line L, and instructed to carry out the switching operation by the switching instruction part 23A so as to be closed, whereby the charges accumulated in the junction capacitance portion of the photodiode PDn are output to the common output line L. On the basis of the instruction from the switching instruction part 23A, the N switches SW1 to SWN carry out the switching operation so that the N switches SW1 to SWN are set to the close state in the different periods and the interval at which each switch SWn is set to the close state is equal to an integral multiple of a base period. As described above, the charge accumulation time of each of the N photodiodes PD1 to PDN is set to an integral multiple of the base period.

Abstract: A system and method for imaging tissue cells at a predetermined depth in the retina of an eye include components that provide for compensation of refractive errors. Specifically, the system basically includes three subassemblies that operate in concert with each other. There is a first subassembly for directing a first light beam into the eye to measure anterior optical aberrations. There is also a second subassembly for directing a second light beam through retinal tissue to a predetermined depth where the tissue cells are located. This second light beam is used to measure phase aberrations introduced by the retinal tissue. And, there is a third subassembly for directing a third light beam to the tissue cell to produce an image of the tissue cell. In the third light beam, the anterior optical aberrations and the phase aberrations have been substantially removed to provide a clearer image of the tissue cell.

Abstract: An interferometric axial eye length measurement apparatus having a light source adapted to produce a beam of partially coherent light, a first mirror and a second mirror disposed in the reference arm, and a processor adapted to control at least the second mirror such that a corneal interference peak and a second interference peak have a non-zero separation. There is at least one variable delay optical element having a delay signal, wherein the delay signal corresponding to a region between the corneal interference peak and second interference peak is substantially linear.

Abstract: Methods, systems and computer program products for generating parameters for software dispersion compensation in optical coherence tomography (OCT) systems are provided. Raw spectral interferogram data is acquired for a given lateral position on a sample and a given reference reflection. A trial spectral phase corresponding to each wavenumber sample of the acquired spectral interferogram data is postulated. The acquired raw spectral data and the postulated trial spectral phase data are assembled into trial complex spectrum data. Trial A-scan data is computed by performing an inverse Fourier transform on the trial complex spectrum data and determining the magnitude of a result.

Abstract: Provided are forward-imaging optical coherence tomography (OCT) systems and probes.

Abstract: A method of measuring a volume in a fluid flow micromechanical device includes: a) providing and positioning an optical apparatus for measuring the profile of a surface; b) providing a device for acquiring and processing the images coming from the optical apparatus for measuring a profile; c) placing the moving member in a first position and then in a second position, and activating the optical apparatus for measuring the profile of the surface to direct a light beam on the reference face, and activating the image acquisition and processor device to obtain a first image in the first position of the moving member and a second image in the second position; and d) comparing the second image with the first image of the reference face to determine the variation in the volume of the cavity generated by the deformation of the moving member.

Abstract: In an optical tomography system, a polarization changing system which converts linearly polarized light too non-linearly polarized light is provided in at least one of a light source unit, an optical path from the light source unit to a light dividing system, the optical path of the measuring light from the light dividing system to an object, the optical path of the reflected light from the object to the combining system and the optical path of the reference light from the light dividing system to the combining system. The polarization changing system is, for instance, a polarization-preserving optical fiber which is disposed so that the direction of polarization of the linearly polarized light and the direction of axis of polarization of the linearly polarized light differ from each other.

Abstract: A fundus oculi observation device acts as an optical image measurement device capable of measuring an OCT image such as a tomographic image of a fundus oculi, or the like, and is configured so as to calculate the signal level of the formed OCT image, determine whether the signal level exceeds a threshold value, and change the position of a reference mirror so that the signal level is determined to exceed the threshold value.

Abstract: Various methods are disclosed for mapping optical coherence tomography (OCT) data to facilitate review and diagnosis. In one aspect, high resolution 2D line scans are obtained along with lower density 3D cube scans and displayed in a manner to provide context to the clinician. In another aspect, OCT data is analyzed to provide information about non-uniformities of the tissue. Binary image maps of maps useful for determining tautness of membranes are also disclosed.

Abstract: An optical coherence tomography apparatus based on spectral interference where object information can be speedily obtained and an information acquisition range in a depth direction can be enlarged, and an ophthalmic apparatus.

Abstract: The inner surface shape of a hole, in particular, the inner surface shape of a hole the entry of which is narrow and which becomes wider further in from the entry, can be measured at a high level of accuracy.

Abstract: The present invention discloses a two-light flux interference exposure device comprising: a laser light source provided in a laser resonator; a single harmonic generation device provided in the laser resonator for converting laser light output by the laser light source to higher harmonics; an etalon provided in the laser resonator so as to serve as a narrowband wavelength filter; a beam splitter dividing laser light output outside the laser resonator into two light fluxes; and an interference optic system causing the light fluxes to interfere with each other on a target to be exposed.

Abstract: In respective measurement operations on a first sample surface area having a layer structure (81) and a characterized second sample surface area (82), light reflected by the region of the sample surface and the reference surface interfere and a sensing device (10) senses light intensity representing interference fringes at intervals during the relative movement along a measurement scan path to provide first intensity data in the form of a first series of intensity values resulting from a measurement operation on the first sample surface area and second intensity data in the form of a second series of intensity values resulting from a measurement operation on the second sample surface area.

Abstract: An image data set acquired by an optical coherence tomography (OCT) system is corrected for effects due to motion of the sample. A first set of A-scans is acquired within a time short enough to avoid any significant motion of the sample. A second more extensive set of A-scans is acquired over an overlapping region on the sample. Significant sample motion may occur during acquisition of the second set. A-scans from the first set are matched with A-scans from the second set, based on similarity between the longitudinal optical scattering profiles they contain. Such matched pairs of A-scans are likely to correspond to the same region in the sample. Comparison of the OCT scanner coordinates that produced each A-scan in a matching pair, in conjunction with any shift in the longitudinal scattering profiles between the pair of A-scans, reveals the displacement of the sample between acquisition of the first and second A-scans in the pair.

Abstract: Described is a multiple channel interferometric surface contour measurement system. The measurement system includes a multiple channel interferometer projector, a digital camera and a processor. The projector includes two or more interferometer channels. Each channel has an optical axis spatially separate from the optical axes of the other channels. Each channel projects a fringe pattern onto the surface of an object to be measured. Image data for the fringe patterns projected on the object surface are acquired by the digital camera. The processor controls the projection of the fringe patterns of different spatial frequencies, adjusts the phase of each fringe pattern and generates surface contour data in response to the camera image data. The multiple channel interferometric surface contour measurement system provides numerous advantages over conventional single channel interferometric systems, including reduced sensitivity to optical noise, improved stability and increased measurement accuracy.

Abstract: A spectral-domain magnetomotive optical coherence tomography apparatus, includes (a) a spectral-domain optical coherence tomography device, and (b) a magnet. The magnet is coupled with the optical coherence tomography device so that changes in the magnetic field are coordinated with collection of data by the optical coherence tomography device. This device may be used to examine a sample by spectral-domain magnetomotive optical coherence tomography, which includes examining the sample with a spectral-domain optical coherence tomography device, to collect optical coherence tomography data. The sample contains magnetic particles, and the magnetic particles are subjected to a changing magnetic field during the examining.

Abstract: The present invention is a tunable semiconductor laser for swept source optical coherence tomography, comprising a semiconductor substrate; a waveguide on top of said substrate with multiple sections of different band gap engineered multiple quantum wells (MQWs); a multiple of distributed feedback (DFB) gratings corresponding to each said band gap engineered MWQs, each DFB having a different Bragg grating period; and anti-reflection (AR) coating deposited on at least the laser emission facet of the laser to suppress the resonance of Fabry-Perot cavity modes. Each DFB MQWs section can be activated and tuned to lase across a fraction of the overall bandwidth as is achievable for a single DFB laser and all sections can be sequentially activated and tuned so as to collectively cover a broad bandwidth, or simultaneously activated and tuned to enable a tunable multi-wavelength laser.