195 results about "Coherent imaging" patented technology

Apparatus and method are provided for transmitting at least one electromagnetic radiation is provided. In particular, at least one optical fiber having at least one end extending along a first axis may be provided. Further, a light transmissive optical arrangement may be provided in optical cooperation with the optical fiber. The optical arrangement may have a first surface having a portion that is perpendicular to a second axis, and a second surface which includes a curved portion. The first axis can be provided at a particular angle that is more than 0° and less than 90° with respect to the second axis.

Frequency domain optical coherence imaging systems have an optical source, an optical detector and an optical transmission path between the optical source and the optical detector. The optical transmission path between the optical source and the optical detector reduces an effective linewidth of the imaging system. The optical source may be a broadband source and the optical transmission path may include a periodic optical filter.

Methods and systems are provided for using optical interferometry in the context of material modification processes such as surgical laser or welding applications. An imaging optical source that produces imaging light. A feedback controller controls at least one processing parameter of the material modification process based on an interferometry output generated using the imaging light. A method of processing interferograms is provided based on homodyne filtering. A method of generating a record of a material modification process using an interferometry output is provided.

After the modulation of reference grating, the light intemsity variation of diffracted light coherent imaging in +-1 stage of the alignment mark is detected at image surface; meanwhile at the pupil surface, the variation of interference signal intensity in each stage being coherent and stacking with the positive, negative diffracted light spot in same stage with the high stage diffracted light of the alignment light is detected. The generated signals have high process versatility, high sensitivity and high S / N ratio.

Frequency domain optical coherence imaging systems have an optical source, an optical detector and an optical transmission path between the optical source and the optical detector. The optical transmission path between the optical source and the optical detector reduces an effective linewidth of the imaging system. The optical source may be a broadband source and the optical transmission path may include a periodic optical filter.

A LADAR system for coherently imaging a target within a volume has a modulated laser transmitter at a frequency and a receiver. The receiver has a plurality of lenses, each with its own detector. Each detector is supplied by a centrally located local oscillator tuned to the frequency. The paths from the local oscillator to each detector, as well as the delay within each lens / detector combination are measured during a calibration. A calibrating reflector reflects a test signal during the calibration at many frequencies, temperatures and accelerations. Measurements of paths and delays obtained during the calibration are stored, and used to phase compensate subsequent target reflections for coherent processing.

The present invention relates to a dual focusing optical coherence imaging system. The dual focusing optical coherence imaging system includes: a light source unit for generating broadband light; a main optical distributor for distributing the light generated from the light source to allow the light to be propagated; an interference unit including first and second interference parts for forming interference signals with respect to different focused areas of an object to be detected using the light distributed from the optical distributor, and a common sample arm commonly connected to the first and second interference parts; an optical switch connected to the first and second interference parts to select at least one of the interference signals transmitted from the first and second interference parts; and a detection unit for converting the interference signal selected by the optical switch according to a preset mode into an electrical signal.

The present invention relates to a functional optical coherent imaging (fOCI) platform comprising at least one active camera unit (ACU) comprising a coherent and / or a partially coherent light source, and means for spectral filtering and imaging a selected body area of interest; an image processing unit (IPU) for pre-processing data received from an ACU; at least one stimulation unit (STU) transmitting a stimulation to a subject; at least one body function reference measurement unit (BFMU); a central clock and processing unit (CCU), with interconnections to the ACU, the IPU, the STU, for collecting pre-processed data from the IPU, stimuli from the STU body function reference data from the BFMU in a synchronized manner; a post-processing unit (statistical analysis unit, SAU); and an operator interface (HOD. Further the invention relates to a process for acquiring stimuli activated subject data comprising the steps of aligning a body function unit at a subject and monitoring pre-selected body function; selecting a stimulus or stimuli; imaging a body area of interest; exerting one or a series of stimuli on the subject; imaging the body area of interest synchronous with said stimuli and the preselected body functions; and transferring said synchronized image, stimuli and body function data to a statistical analysis unit (SAU) and performing calculations to generate results pertaining to body functions.

A coherent light source system is presented. The system comprises at least one coherent light emitter producing a coherent light beam, a focusing lens unit, and a beam shaper unit, the beam shaper unit being accommodated between the coherent light emitter and the collimating lens unit being in a front focal plane of the focusing lens unit, thereby providing a substantially uniform profile and high-degree collimation at a desired plane in an optical path of light propagation.

The present invention provides an alignment system, alignment method and alignment mark. The alignment mark comprises a long cycle fiber grating branch and a short cycle fiber grating branch. The present invention adopts an optical-path-splitting detection system, simultaneously has signal acquisition, treatment and fitting for plus or minus 1 grade diffraction light coherent imaging of the long cycle fiber grating branch and the plus or minus 1 grade diffraction light coherent imaging of the short cycle fiber grating branch which constitute a fiber grating mark, and further combines phase information of two combinations of the signals to determine the accurate alignment position. Due to only adopting the plus or minus 1 grade diffraction light coherent imaging, the present invention avoids the adoption of a space separation device with a wedge plate regulating device required by high-grade diffraction light. By adopting the short cycle fiber grating branch, the obtainment of the higher alignment accuracy can be guaranteed. The present invention avoids crosstalk phenomenon between coarse alignment signals and fine alignment signals by adopting the optical-path-splitting detection system.

Retrospective dynamic transmit beamformation is provided in medical ultrasound imaging. Using parallel receive beamformation, sets of data representing locations in at least a common field of view are obtained, each set in response to a transmit with a spatially distinct phase front. The common field of view receive data are time aligned and amplitude weighted for retrospective transmit focusing and retrospective transmit apodization, respectively. A time offset, such as of a cycle or more in some cases, is applied to the receive data for retrospective transmit focusing. The offset is selected to emulate shifting the transmit delay profile to be tangentially intersecting with the dynamic receive delay profile for each location which is the desired transmit delay profile. A weight is applied to the receive data for retrospective transmit apodization. The weight is selected based on the desired transmit apodization profile. The offset and weighted data representing a same location from different transmit events is coherently combined. The number of sets of data offset, weighted and combined may vary as a function of depth for dynamic transmit beamformation.

The invention belongs to the technical field of radar imaging, and particularly discloses a method for realizing three-dimensional coherent imaging by a ground penetrating radar under near field condition. The method is characterized by comprising the following steps of: 1) transmitting radar waves to a target at transmission frequency f, and performing difference frequency processing on a target echo signal received by the radar and a reference signal to obtain a difference frequency processed echo signal; 2) interpolating the difference frequency processed echo signal, and performing range direction compression; 3) dividing an imaging area into grids, and calculating delays of each grid point or pixel point, delayed by the radar, in the imaging area at each azimuthal position; 4) performing phase compensation on echoes of corresponding points according to the calculated delays; 5) performing coherence addition on each pixel point to obtain an addition result which is a value of the pixel point; and 6) traversing the whole imaging area by adopting the steps 4) and 5) to obtain an imaging function, and finishing the reconstruction of an image. In the method for realizing the three-dimensional coherent imaging by the ground penetrating radar under the near field condition, the three-dimensional imaging is performed on a near field target area, and relatively higher resolution is ensured.

The invention discloses a pump detection method based on 4f phase coherence images. Wherein, the laser output by a laser is divided into a pumping light and detecting light; the pumping light is focused after a time-delay platform on a non-linear sample to generate non linearity; the detecting light detects the change in the pumping-light induced non-linear sample, and is recorded by a CCD. By different time delays in the pumping light, the change in the phase and strength of the detecting light emitted from the sample reflects the distribution of particles in the sample at different time periods, so that the absorption sections and service lives and refractivity volume of each energy level are determined. The invention is of simple optic path, the theoretic processing is simple, the single-phase measurement reduces the optic accumulation; the absorption and refracting pumping are completed at the same time without individual measurements, and the size and symbol of non-linear absorption and refraction can be measured concurrently, the sensitivity on the random fluctuation of the laser beam is low, and the measurement results are accurate.

The invention discloses real-time imaging skin diagnosis equipment by optical coherence tomography, and belongs to the field of optical imaging equipment. The equipment comprises a power supply, a light source control circuit, a light source, an indicating light source, a first optical fiber coupler, a second optical fiber coupler, an OCT probe, an optical delay line, a photo detector, a signal processing and control circuit, and a computation processing and display device. The imaging equipment takes the optical coherence tomography (OCT probe) as a core, processes signals rapidly by the signal processing and control circuit, and improves the imaging speed and image resolution by cooperating with the computation processing and display device; designs of a wideband light source and a duckbill-shaped probe applicable to skin scanning cause the equipment to be applicable to scanning human skin, and real-time and rapid imaging can be realized by cooperation of the signal processing and control circuit with the computation processing and display device.

Systems and methods are provided for multi-function coherent imaging comprising directing a first coherent radiation beam and a second coherent radiation beam towards a detector, where the second coherent radiation beam is spatially offset, angularly offset, or spatially and angularly offset from the first coherent radiation beam. A portion of the first coherent radiation beam and a portion of the second coherent radiation beam may be combined to form a composite beam. An object may be radiated with the composite beam. A first intensity pattern may be formed by interfering with return radiation from the radiated object with the first coherent radiation beam and a second intensity pattern is formed with the return radiation from the radiated object and the second coherent radiation beam. A detector may simultaneously record a superposition of the first intensity pattern and the second intensity pattern.

The invention discloses a method which can measure the optical nonlinearity of a medium interface and apply the reflected light to measure the film optical nonlinearity, which belongs to the nonlinear photonics material and nonlinear optical information processing fields. An incident laser light is divided into two ways through a beam splitting prism, one way is a probe light which enters a measure optical path and is collected by a CCD camera after passing through a 4f phase coherent imaging system; and the other way is a reference light; and the method is characterized in that: the sample is placed on a focal plane of a first convex lens of the measure optical path in a reflection mode, a second convex lens having the same focal length with the first convex lens is positioned at the one-time focal length part along the transmission direction of the reflected light, thereby forming the reflection 4f phase coherent imaging system; and the measurements include two parts of energy calibration and optical nonlinearity measurement. The method has the advantages of convenient measurement, simple optical path, non movement of sample, single pulse measurement, being not easy to damage medium surfaces, and having low requirements to stability of light source energy and space.

The invention provides a device and a method for measuring the optical position. The method comprises the following steps: adopting a grating diffraction order enhancing method, namely regularly changing the breadth of a grating bar and the depth of a grating slot to obtain a corresponding diffraction order enhanced grating so as to enhance a position measurement signal. The measuring device adopts the grating with two types of cycles as reference marks, namely a first grating and a second grating, uses the light intensity changes modulated by the reference marks after the + / -1 order diffraction light coherent imaging of the first grating and the second grating to obtain large-scale position capture through phase information of a transmitted light signal, simultaneously uses one of the grating to perform enhancement of a corresponding diffraction order, and uses coherent image scanning of the enhanced high diffraction order to perform precise position measurement. Compared with the prior art, the reference marks adopt a grating diffraction order enhancing technique to achieve the position alignment precision, thus the method can support two-dimensional marks and one-dimensional marks.

The present invention provides a novel optical synthesis aperture imaging system based on the optical fiber array. The high-resolution image can be obtained by the imaging technique of synthesizing a plurality of small apertures to a synthesis aperture. The acquired accomplishment of optical synthesis aperture imaging in the high resolution imaging displays that the technique has a wide developing prospect. The invention receives the optical wave radiated from the target by a Cassegrain telescope array. The optical fiber is coupled in a single-mode polarization-preserving fiber for transmitting. An optical fiber collimator array is used for leading to coherent imaging of the light beam. The phase error compensation is executed through a piezoelectric ceramic phase modulator and an optical fiber delay line. The whole set of equipment goes for miniaturization and lightening, and can be applied in the fields of astronomical measurement, remote sensing the plant cover, monitoring the environment and disaster and the like.

This invention relates to a sort of alignment mark, and this alignment mark is the multiply periodic grating configuration. It consists of several group of the different periodic grating. This invention also offers a sort of imaging optical system of this alignment mark, and the alignment mark from the picture by this optical system, and it consists of this cohere imaging system at least. The first imaging system consists of frontal group lens, the first space wave filter, and the first back group lens. The second consists of the frontal group lens, the second space wave filter, and the second back group lens. This invention also offers a sort of the method which adopts this optical system to produce the picture to the alignment mark. This method consists of this approach: Offer and transfer the laser illuminating beam of light, and irradiate it to the alignment mark. Adopt the diffraction light and the reflex of the alignment mark. The diffraction light produces the picture by the first coheres imaging system and the second cohere imaging system of the optical system. This invention advances the detecting precision of the alignment mark availably.

An OCI medical device includes a coherent light source, a light sensor, a first processing unit adapted to calculate OCI Data from the light sensor, a control unit which allows taking or loading of at least one Reference OCI Value, a second processing unit adapted to calculate the Intra-Individual Relative Assessment of the OCI Data of an Imaging Zone and the at least one OCI Reference Value, and display means adapted to show at least one Relative OCI Value. Uses and a method for assessing the blood flow of a body region use OCI imaging and include an Intra-Individual Relative Assessment between OCI Data of the Imaging Zone and at least one Reference OCI Value.

The present invention relates to a real-time imaged optical coherence endoscopic system. Said invention includes broad-band light source, optical fibre coupler, sample arm and reference arm, position detector and computer collecting and processing system, and said system structure is based on Michelson interferometer, the described reference arm adopts the scanning disk connected with motor, and said scanning disk is formed from central shaft and flabellum which is placed on the central shaft and whose at least one surface form is equidistant spiral surface. The sample arm adopts micro-type optical transmission and scanning device based on ultrasonic motor. Said invention is simple in structure and can provide scanning range greater than 3 mm.

The invention relates to a sweep frequency optical coherent imaging system based on optical calculation. The system is characterized by comprising a sweep frequency interference system and an optical calculation system; the sweep frequency interference system comprises a pulse laser, a sweep frequency optical device, an OCT interferometer and a photoelectric detector; the optical calculation system comprises a radio frequency amplifier, an optical intensity modulator, a broadband light source, a dispersion device, a Mach-Zehnder interferometer, a balance detector, an envelope detector, a data acquisition card and a computer. Real-time Fourier transformation of optical frequency domain signals is achieved, due to the fact that Fourier transformation can process image data of the sweep frequency optical coherent imaging system in time, the imaging speed of the system is extremely high, and the system can be widely applied to sweep frequency optical coherent imaging.

A photoepilation device including a compact hand piece applicator and a portable electronics module for use in a non-medical setting. The hand piece, which contains no electrical signals, allows the user to focus on individual hair follicles by observing a magnified image provided on a semiconductor display. The image from the hand piece is transported to a remote CCD through a coherent imaging fiber, which also delivers the therapeutic energy pulse from a remotely located source to the localized target. Destruction of pluripotential follicular stems cells found in the hair bulb and bulge regions is possible via a single low power laser diode. Control of pulse width and spot size attains a range of fluence levels up to 85 J·cm−2.

The invention relates to a complex amplitude object reconstruction device based on the optical scanning holographic technique. The complex amplitude object reconstruction device comprises a difference frequency laser coherent unit, a two-dimensional scanning unit, a photoelectric information receiving and processing unit and a computer reconstruction complex amplitude unit; the reconstruction of the complex amplitude object is realized based on the difference frequency scanning technology which is simpler and easy to realize when being compared with the conventional coherent optical scanning holographic technique. The complex amplitude object reconstruction device can be applied to the field of biology microscope, particularly to the field of transparent or weak-absorption biological sample detection, has the advantage of being superior to other biological imaging techniques, can realize coherent-imaging on the premise of ensuring the imaging resolution, can further obtain more information of the sample related to the refractive index, thereby being quite good in the application prospect in biomedicine.

The invention discloses an imaging method of a super-speed coaxial framing coherent imaging light path. According to the method, an object to be shot is lighted by coaxial train pulse laser light, a coherent shutter is achieved by means of the interference between a beam of reference light and the coaxial train pulse laser light so as to control the showing of image information, contained in a specific pulse of the train pulse laser light, of the object to be shot, image information contained in each pulse of the train pulse laser light can be shown respectively by means of multiple beams of reference light with different delays, and then framing imaging is achieved. According to the imaging method of the super-speed coaxial framing coherent imaging light path, mechanical or electronic shutter devices are not needed, super-speed and coaxial framing imaging of an transient physical process can be achieved by means of an all-optical light path, image resolution is high, imaging frequency is high, each image has a spatial bandwidth the same as that in the case of single imaging, the situation that the more the frames are, the smaller the bandwidth is does not exist, spatial discrimination sacrifice is avoided, and the imaging frequency is determined by train pulse separation.

The invention relates to a frequency domain imaging method of a ground penetrating radar, which is a frequency domain imaging algorithm based on linear frequency modulation waves. The method comprises the steps of performing difference frequency treatment on a target echo signal received by the radar and a reference signal, obtaining an echo wave after the difference frequency; performing Fourier transform on a two-dimensional scanning direction of the echo wave; and then performing phase compensation on data by taking an imaging central point as a reference point; then, performing secondary slot interpolation operation; decoupling three-dimensional imaging data by the slot interpolation; and finally, performing three-dimensional Fourier transform on data after slot interpolation, thereby accomplishing reconstruction of images. According to the frequency domain imaging method of the ground penetrating radar, the problem in three-dimensional coherent imaging under near field condition is solved, and compared with a conventional pulsed incoherent imaging technology, and images with better resolution ratio can be obtained.

The invention relates to a passive millimeter wave focal plane image formation device, belonging to the field of passive millimeter wave image formation device and aiming to solve the problem of limited pixel and low image formation resolution faced by the existing image formation device. The device comprises N-numbered feed sources and N-numbered millimeter wave radiometer channels; the N-numbered feed sources are arranged on the focal plane of focusing antenna in the form of linear array; each millimeter wave radiometer channel is composed of a radio-frequency amplifier, a radio-frequency filter, a frequency mixer and an A / D converter which are connected in series in sequence; N-numbered intermediate frequency digital signals are transmitted to a computer for carrying out self-correlation and mutual correlation processing, the computer obtains antenna temperature Tai and interferometry temperature Tcij, the computer then processes the antenna temperature Tai to obtain pixel value Ti and inserts the interferometry temperature Tcij between pixel value Ti and Tj to mutually form an focal plane image. In the invention, coherent image formation and incoherent image formation are effectively combined, so that the number of pixels of the image is increased and spatial resolution of image formation is improved.