595 results about "Polarization splitter" patented technology

By using low-frequency signals, an optical transmitting unit modulates one of a wavelength, a transmission timing, and an intensity of light as a carrier wave. A polarization multiplexer synthesizes the output light signals, modulated by the optical transmitting unit, in polarization states orthogonal to each other and generates polarization-multiplexing signals. A polarization splitter splits by extracting two orthogonal polarization components from the polarization-multiplexing signals. The polarization states of the polarization-multiplexing signals are controlled by a polarization controller in an optical receiving unit. A band-pass filter extracts components transmitting through passbands from output signals of the optical receiving unit and outputs an intensity of the components. Based on the intensity output from the filter, a controlling circuit generates feedback control signals for maximizing a ratio of the components of the low-frequency signals and by using the feedback control signals, the polarization controller controls the polarization states of the optical multiplexing signals.

An illumination system for a projection exposure machine, operating with ultraviolet light, for microlithography has an angle-conserving light mixing device with at least one integrator rod that has an entrance surface for receiving light from a light source, and an exit surface for outputting exit light mixed by the integrator rod. At least one prism arrangement for receiving exit light and for varying the state of polarization of the exit light is placed downstream of the integrator rod. A preferred prism arrangement has a polarization splitter surface, aligned transversely to the direction of propagation of the exit light, which passes light fractions with p-polarization without hindrance, and reflects fractions with s-polarization. The separated beams with orthogonal polarization are parallelized by means of a reflecting surface aligned parallel to the polarization splitter surface, and the same state of polarization is set for both partial beams by means of a suitable retarder.

The invention discloses a double-frequency grating interferometer displacement measurement system. The system comprises a double-frequency laser device, an interferometer, a measuring grating and an electrical signal processing portion. The measurement system achieves displacement measurement based on optical grating diffraction, the optical doppler principle and an optical beat frequency principle. The double-frequency laser device transmits double-frequency laser, the laser is divided into reference light and measuring light through a polarizing beam splitter, the measuring light transmits into a position of the measuring grating, positive and negative first-order diffraction occurs, diffraction light and the reference light form a beat frequency signal which contains displacement information in two directions at the position of a light detection unit, and linear displacement output is achieved through signal processing. According to the system, the sub-nanometer-grade or even higher grade of resolution ratio and accuracy can be achieved, and horizontal large-stroke displacement and horizontal displacement can be measured at the same time. The system has the advantages of being insensitive to the environment, high in measuring accuracy, small in volume and light in weight. The system serves as a lithography machine ultraprecise workpiece platform position measurement system, the comprehensive performance of the workpiece platform can be improved.

The invention discloses a two-dimensional photoelectric auto-collimation method and device for polarized light pyramid target common-path compensation, belonging to the technical field of precision instrument manufacture and precision measurement. According to the invention, high-precision photoelectric autocollimation angle measurement is realized for solving the defects in the existing method and device. The method comprises: a common-path shift quantity monitoring separating device based on a pyramid combined target can be used for curing a polarizing light splitter, a pyramid reflector and a measurement reflector to form the pyramid combined target, and separating a reference light beam which has a feature identical to that of a measurement light beam and is in common-path transmission with the measurement light beam while obtaining a two-dimensional angle variation by using the linear polarization feature of the laser; a controller is used for controlling a two-dimensional light beam deflection device in real time according to the shift quantity reflected by the reference light beam so as to inhibit the shift quantity coupled in the measurement light beam, thus the precision measurement on the two-dimensional angle variation is realized. The device for realizing the method comprises a two-dimensional photoelectric auto-collimation tube, the common-path shift quantity monitoring separating device based on the pyramid combined target, the controller and the two-dimensional light beam deflection device.

An apparatus, a polarization diversity receiver and a method of receiving a received optical signal. In one embodiment, the apparatus includes: (1) an optical device configured to separate in-phase and quadrature components of a received optical signal, to transmit the in-phase components to a first optical output thereof and to transmit the quadrature components to a second optical output thereof, (2) a first polarization splitter coupled to receive light at the first optical output and (3) a second polarization splitter coupled to receive light at the second optical output.

A dual-frequency laser ranging method and a device based on polarization state regulation and wavelength synthesis belong to the technical field of laser application. In absolute distance measurement and relative displacement measurement, the method adopts the same frequency stabilized laser as a measuring light source, realizes organic integration of absolute distance measurement and relative displacement dynamic measurement through the control of a polarization rotator and wavelength tuning of acoustooptic frequency shifters and simultaneously meets the requirements on extra long distance precise measurement and fast local displacement ultraprecise monitoring. The device comprises an acoustooptic frequency shifter A and an acoustooptic frequency shifter B, a reflecting mirror A and a reflecting mirror B, a frequency control unit A and a frequency control unit B, a polarization rotator, a polarization splitter B and a laser wavelength split and synthesis unit formed by partial optical splitters. The invention has the advantages of both extra long distance ultraprecise measurement capability and integral formation, etc.

It is an optics array co-focus ultra-resolution micro three-dimension detection device, which comprises spot light source, calibration lens, microscope array and pinhole array, beam expansion lens, polarization light-splitting lens, a quarter of wavelet, binary iris filter, lens, carrier bench, collection lens, detection probes array and surface array CCD. The spot source forms parallel light through calibration lens into the micro lens array and then forms spot light array onto the beam expansion lens focus plane through pinhole array and forms polarization light through polarization light-splitting lens and a quarter of wavelet and emits onto the object surface to be measured through binary iris filter and lens.

The invention discloses a laser heterodyne interference linearity measuring device and a laser heterodyne interference linearity measuring method with six-degree-of-freedom detection. The laser heterodyne interference linearity measuring device comprises a laser heterodyne interference linearity and position detection part and an error detection and compensation part; a four-degree-of-freedom error detection light path consisting of three ordinary beam splitters, a polarizing beam splitter, a plane reflecting mirror, a convex lens, a position sensitive detector and two four-quadrant detectors is additionally arranged in a light path structure of the laser heterodyne interference linearity and position detection part. By utilizing a method for integrating the laser heterodyne interferometry and a laser spot detection method, the simultaneous six-degree-of-freedom detection of a deflection angle, a pitch angle, a rolling angle, horizontal linearity, vertical linearity and linearity position of a measured object can be realized, the error compensation is carried out for the vertical linearity and the vertical linearity position, the influence of rotation error of the measured object on a measurement result in the linearity measuring process can be eliminated, and the measurement precision of the laser heterodyne interference linearity and the position of the laser heterodyne interference linearity can be improved.

The invention relates to a method of reducing the heterodyne interference non-linear error first harmonic component and its equipment, the existing kinds of system and the method are all very complex. The invention includes: the light beams which contains two frequencies, two polarization directions and sends out by the double frequency laser; this light beam divides into two bunches of light after the spectroscope, the reflected light forms the reference signal after the analyzer by the photo detector receive; the transmitted light enters the polarization spectroscope to divide into two bunches of light which includes the reflected light of polarization direction vertical paper surface and parallel paper surface transmitted light, the reflected light reflects to the polarization spectroscope after the reference pyramid prism, the transmitted light after survey pyramid prism installed on the swivel table also reflects the polarization spectroscope; above two bunches of light converge in the polarization spectroscope place, and formed the survey signal by the reflector reflection after the analyzer by the photo detector; swivel table axial revolves the survey pyramid prism along the survey pyramid prism heading, swivel table anti-clockwise or clockwise axial revolves 97 degree. The invention uses to increase the heterodyne interference measuring accuracy.

An optical transmission system includes a polarization multiplexing optical transmitter for transmitting an optical signal, where an X-polarized signal and a Y-polarized signal each having a having predetermined frame structure are polarization-multiplexed, to an optical fiber transmission path, and a polarization multiplexing receiver for receiving the optical signal that has propagated through the optical transmission path. The polarization multiplexing optical transmitter delays a frame assignment signal (FAS) in the Y-polarized signal, by a predetermined delay time τ, relative to FAS in the X-polarized signal. The polarization multiplexing optical receiver includes a polarization splitter for splitting the received optical signal into two branches of polarized signals which are orthogonal to each other, a time difference detector for detecting a time difference of FASs between the two polarized signals, and a polarization identifying unit for identifying which of the two polarized signals is the X-polarized signal or Y-polarized signal.

The invention relates to a method for transmitting at least one first and second data signal in polarization multiplex. To this end, the invention provides that, in a first step, the first data signal is, on the transmit side, modulated to a sideband of a first carrier signal for generating a first sideband-modulated signal, and the second data signal is modulated to a sideband of a second carrier signal in order to generate a second sideband-modulated signal. In a second step, the first and second sideband-modulated signal are subsequently polarized orthogonal to one another, combined to form an optical multiplex signal and transmitted. In a third step, the optical multiplex signal is, on the receive side, guided via a polarization control element to a polarization splitter that separates the transmitted optical multiplex signal into the first and second sideband-modulated signal. In a fourth step, the first sideband-modulated signal is converted into a first electrical signal and / or the second sideband-modulated signals are / is converted into a second electrical signal. In a fifth step, the first and / or second electrical signal are / is evaluated and at least one control signal for controlling the polarization control element is derived on the basis of this evaluation.

A speckle reducing device includes: a polarization splitter element with a polarization splitter portion that splits incident light into first and second light containing a first and a second component respectively, which outputs the first and the second light along different directions; a first reflecting member that reflects the first light to reenter the polarization splitter element; a first conversion member disposed between the first reflecting member and the polarization splitter element, which converts the first light to third light containing the second component; a second reflecting member that reflects the third light to reenter the polarization splitter element; and a second conversion member disposed between the second reflecting member and the polarization splitter element, which converts the third light to fourth light containing the first component, wherein: the polarization splitter element outputs the second and the fourth light along one direction.

The invention belongs to the technical field of optical microscopic imaging and optical precision measurement and relates to a super-resolution differential con-focal microscope with both macro field coverage observation and micro field coverage observation. The invention mainly comprises a laser (1), a beam expander (2), a spectroscope (4), a polarization spectroscope (5), a range extension tracking and measuring system (6), a measuring objective lens (7), two optical collectors (16) and (19), pinholes (17) and (20), detectors (18) and (21), an LED light emitting diode (12) which is arranged in a direction opposite to the reflection direction of the spectroscope and a CCD detector (11) which is arranged in a direction opposite to the reflection direction of a spectroscope (9). The LED light emitting diode and the CCD detector are used for realizing macro-field coverage observation of a con-focal microscope through imaging the surface type of the detected samples, and the axial resolution power of the con-focal microscope can be raised through deploying the optical path of the differential con-focal microscope.

A polarization-insensitive optical receiver for demodulating a phase-modulated input optical signal is provided. The optical receiver includes successively a polarization splitter, a first and second interferometric modules including respective delay lines, and a plurality of detectors. The input optical signal is split into two substantially orthogonally-polarized components, which are launched along respective optical paths into the corresponding interferometric modules where they demodulated and subsequently recombined prior to being detected by the plurality of detectors. Advantageously, the optical receiver allows mitigating undesired discrepancies between the optical paths traveled by the two polarization components by arranging the respective delay lines of the interferometric modules into intertwined spiraling structures. A waveguide assembly including a substrate and a pair of waveguides on the substrate and defining intertwined spiraling structures is also provided, as well as a waveguide coupling assembly for coupling, onto a same detector, two optical signals travelling along two parallel coplanar waveguides.

The automobile collision-proof one-dimensional scanning lidar system includes casing, laser, polarizing spectroscope, optical beam expander, quarter wave plate, reflector, one-dimensional scanning vibration mirror, light detector, amplifier, signal processing system, display and warning system and brake system. The present invention has low cost, small size, easy installation, high scanning frequency, precise detection of obstacle direction and long detection distance, and possesses functions of target distinction, ranging, measuring speed, intelligently keeping away from obstacle, etc. to prevent collision to various kinds of obstacle.

The invention belongs to the technical field of biomedical engineering, and relates to an integration imaging system used for early stage cervical carcinoma detection and integrating fluorescent mesoscope imaging and optical coherence tomography (OCT). The integration imaging system comprises a fluorescent mesoscope imaging system and a spectrum OCT system. The fluorescent mesoscope imaging system comprises a laser light source, a polarizer, a polarized light spectroscope, a first dichroscope, a second dichroscope, an X-Y scanning galvanometer, an objective lens, a fluorescent detection part, a diffused light detection part and a computer, wherein the X-Y scanning galvanometer and the objective lens are shared by the spectrum OCT system. The spectrum OCT system comprises a low-coherent light source, a fiber polarization splitter, a focusing lens, the X-Y scanning galvanometer, the objective lens and a spectrograph. Ultraviolet light beams generated by the laser light source pass through the polarizer, the polarized light spectroscope and the first dichroscope and then are reflected through the second dichroscope, and samples generated by the low-coherent light source are collimated through the focusing lens and are combined with the ultraviolet light beams. The system improves diagnostic specificity through mutual evidence of organization function information and histomorphology information.

An illumination system for a projection exposure machine, operating with ultraviolet light, for microlithography has an angle-conserving light mixing device with at least one integrator rod that has an entrance surface for receiving light from a light source, and an exit surface for outputting exit light mixed by the integrator rod. At least one prism arrangement for receiving exit light and for varying the state of polarization of the exit light is placed downstream of the integrator rod. A preferred prism arrangement has a polarization splitter surface, aligned transversely to the direction of propagation of the exit light, which passes light fractions with p-polarization without hindrance, and reflects fractions with s-polarization. The separated beams with orthogonal polarization are parallelized by means of a reflecting surface aligned parallel to the polarization splitter surface, and the same state of polarization is set for both partial beams by means of a suitable retarder.

An apparatus comprising a planar optical structure that includes an input coupler, first and second planar waveguides and an output coupler, all on a planar substrate. The input coupler is configured to divide an incoming light into two input light beams. Each of the first and second waveguides is configured to receive one of the two input light beams. The first waveguide has a first core with a width that is greater than a width of a second core of the second waveguide. At least one of the first or second planar waveguides is birefringent. The output coupler is configured to receive the light beams after passage through the first and second waveguides. A first output light beam from the output coupler is substantially TE polarized light and a second output light beam from the output coupler is substantially TM polarized light.

The invention discloses a method and device for high-accuracy and small-angle measurement, wherein the method comprises the following steps: polarizing and splitting the reference light beam which is obtained after the collimation processing to obtain the first linearly polarized light; converting into the circularly polarized light and radiating to a measuring target mirror after the beam expansion; detecting the reverse return of the light beam which is reflected by the target mirror; carrying out the beam contraction and the secondary conversion to obtain the second linearly polarized light; polarizing and splitting the second linearly polarized light again and dividing the second linearly polarized light into the reflected light and the transmission light which have the light intensity ratio of 1 to 1; respectively radiating the two beams of light to two prisms to be reflected; and respectively receiving and processing the reflected light signals through two detectors. The device disclosed by the invention comprises a laser emitting unit, a beam expansion lens unit, a measuring target mirror unit and a differential detection unit, wherein the laser emitting unit comprises a light source, a single mode fiber, a collimation lens, a polarization splitter and a lambda / 4 wave plate; and the differential detection unit comprises the splitter, the two prisms and the two detectors. The method and device disclosed by the invention have the advantages of ultrahigh accuracy and large measuring range.

A two-DOF (degree of freedom) heterodyne grating interferometer displacement measurement system comprises a two-frequency laser, a grating interferometer, a measuring grating, a receiver, and an electronic signal processing part. The grating interferometer comprises a polarizing beam splitter, a reference grating and a refraction element. The measurement system measures displacement according to optical grating diffraction, optical Doppler Effect and optical beat frequency principle. A two-frequency laser beam emitted by the two-frequency laser enter the grating interferometer and the measuring grating before two light signals are output to the receiver, and the signals are sent to the electronic signal processing part. When the grating interferometer is in two-DOF linear relative motion with the measuring grating, the system can output two linear displacements. The measurement system allows for sub-nano or higher resolution and precision, and can measure two linear displacements simultaneously. The measurement system has the advantages of insensitivity to environment, high measurement precision, small size, light weight and the like, and after the measurement system is used as a lithography machine ultra-precision workpiece bench position measurement system, comprehensive performances of a workpiece bench can be improved.

Disclosed are an optical transceiver and an passive optical network using the same. The optical transceiver includes a polarization splitter for splitting injected light input from an outside of the optical transceiver into a first polarization component and a second polarization component, a light injected transmitter for receiving the first polarization component and outputting an optical signal generated based on the first polarization component, and an optical receiver for detecting an electrical signal based on the second polarization component.

The invention discloses a two-dimensional photoelectric auto-collimation method and device of polarized light plane mirror reference common-path compensation, and the method and device provided by the invention belong to the technical field of precision instrument manufacture and precision measurement. According to the invention, high-precision photoelectric autocollimation angle measurement is realized for solving the defects in the existing method and device. The method comprises: a plane mirror reference common-path shift quantity monitoring separating device can be used for separating a reference light beam with the feature identical to the that of a measurement light beam, especially the reference light beam which is in the common-path transmission with the measurement light beam, while obtaining measurement light beam in a two-dimensional angle variation by using the polarization feature of the laser and using a polarizing beam splitter and a reference plane reflector; and a controller can be used for controlling a two-dimensional light beam deflection device in real time according to the shift quantity reflected by the reference light beam so as to inhibit the shift quantity coupled in the measurement light beam, thus the precision measurement on the two-dimensional angle variation is realized. The device for realizing the method comprises a two-dimensional photoelectric auto-collimation tube, the plane mirror reference common-path shift quantity monitoring separating device, the controller and the two-dimensional light beam deflection device.

Disclosed are an optical transceiver and an passive optical network using the same. The optical transceiver includes a polarization splitter for splitting injected light input from an outside of the optical transceiver into a first polarization component and a second polarization component, a light injected transmitter for receiving the first polarization component and outputting an optical signal generated based on the first polarization component, and an optical receiver for detecting an electrical signal based on the second polarization component.

The invention discloses a secondary confocal measuring method and device based on phase-shifting interference, in the device, the laser emits polarizing light beam, the light beam is converted into approximate ideal plane wave after passing through a collimation beam expending lens; the light beam is converted into round polarizing light beam after passing through a polarizing spectroscope and a one-quarter glass; then the light beam is divided into two light beams, wherein the first light beam is focused on a point detector composed by a second pinhole and a detector after being transmitted by a spectroscope, reflected by a reflection lens, reflected by a spectroscope, and focused by a collecting objective lens; the second light is focused on the measuring surface via a detecting focusing objective lens and a spectroscope after being reflected by the spectroscope, and then focused on a point detector via a detecting focusing objective lens and a collecting objective lens after being reflected by the measuring surface; a first micro driver is used for driving the reflecting lens to change phase difference between the reference light and the measuring light in order to realize phase-shifting interference; the initial position of detecting point is the first confocal state. The invention also discloses a secondary confocal measuring method based on phase-shifting interference.

An integrated optic polarization splitter, includes a pair of waveguide elements with a first waveguide element having horizontal orientation and a second waveguide element having a vertical orientation formed from a plurality of waveguide core layers. The first and second waveguide elements are intersected or nearly intersected at one end of the structure and separated at the other end of the structure and the transition there between is made to be adiabatic. The waveguide elements receive an optical signal having both a TE component and a TM component. The TE component propagates along the horizontally oriented waveguide element and the TM component propagates along the vertically oriented waveguide element.

An interferometric optical analyzer apparatus comprises a light source, an interferometer and a detection system for determining the linear response, and subsequently any optical parameter, of one or more optical elements using substantially unpolarized light. In one embodiment, the light source supplies substantially unpolarized coherent light over a predetermined range of optical frequencies. The optical element is coupled in one arm of the interferometer and the other arm of the interferometer is used as a reference. The unpolarized light is first passed through the interferometer then through a three-way polarization splitter unit to split the light into at least three light beams according to preselected polarization axes corresponding to three linearly independent states of polarization. The three light beams are coupled to individual detectors and a controller computes Jones matrix elements from the resulting electrical signals. The total polarization independent power may also be determined by an additional detector.

The invention provides a confocal microscopy measuring device based on measured surface fluorescence excitation, and belongs to the technical field of surface topography measurement. The confocal microscopy measuring device comprises a laser device, a collimation beam expander, a polarizing beam splitter, a quarter-wave plate, a detection objective lens, a tested part, a collection objective lens, a pinhole and a detector, wherein the collimation beam expander and the polarizing beam splitter are configured on a collineation light path of the laser device along the light propagation direction; the quarter-wave plate, the detection objective lens and the tested part are configured on the reflection light path of the polarizing beam splitter; the collection objective lens, the pinhole and the detector are configured on the transmission light path of the polarizing beam splitter; a narrow band filter is contained inside the detector; and the tested part is borne by a micrometric displacement objective table, and the surface of the tested part is coated with a film in a vacuum evaporating coating method. By means of the design that surface characteristics of the tested surface are changed through film coating, the fact that measurement light can return back to a detection system after being reflected by the tested surface is guaranteed, the difficult problems of detection of a large numerical aperture (NA) and high gradient surface are resolved, and the confocal microscopy measuring device is suitable for ultra precise measurement of three-dimensional shapes with large NA and high gradient spherical surfaces, aspheric surfaces and free-form surfaces.

The invention discloses a double frequency laser grating interference two-dimensional measurement method and system with optical aliasing resistance, and belongs to a grating measurement technology. The system comprises a laser device, a grating interference mirror set and a photoelectric detection and signal processing unit. Two laser beams which are simultaneously output by the laser device, different in frequency and separated in space enter a polarizing beam splitter in parallel and in an incident mode. The first laser beam enters a reference grating in an incident mode after being reflected by the polarizing beam splitter to form multiple reference diffraction laser beams with multiple levels, the second laser beam enters a measurement grating in an incident mode after being transmitted by the polarizing beam splitter to form multiple measurement diffraction laser beams, three of the reference diffraction laser beams are sequentially and correspondingly joint with the 0 laser beam, the +1 laser beam and the -1 laser beam in the measurement diffraction laser beams respectively to form an optical beat frequency, and two-dimensional relative motion information of the measurement grating is acquired through photoelectric detection and signal processing. By the adoption of the method and system, optical frequency aliasing, polarization state aliasing and corresponding periodic non-linear errors caused by traditional incomplete polarizing beam splitting are eliminated, and combination properties of a photoetching machine ultra-precise workpiece table position measurement system can be improved when the double frequency laser grating interference two-dimensional measurement system is used for the photoetching machine ultra-precise workpiece table position measurement system.

The invention is a kind of sizing ring light beam differential confocal sensor with high spatial resolution. It includes laser device, beam expanding device, pin hole, ring light sizing device, adjustable light conjunction, polarized beam splitter, 1 / 4 wave piece, tracing inductance sensor, measuring lens, the beam splitter, collecting mirror, pin hole and two photoelectric detector behind the two holes. The invention combines the optical hyper resolution and differential confocal micro trancing technology, in order to enhance the resolution and the range of the sensor; it caters the demands of high spatial resolution, high accuracy, and large measuring range. Especially applies to the measurement of tiny structure, micro stage, tiny grooves, line width and the surface shape.

An optical system of an atomic oscillator includes: a coherent light source emitting two resonant light components each having a p-polarized light component and an s-polarized light component, the tow resonant light components being coherent light and having a different frequency each other; a polarization splitter arranged at an output side of the coherent light source, the polarization splitter transmitting one of the p-polarized light component and the s-polarized light component and changes an optical path of the other of the p-polarized light component and the s-polarized light component to be outputted; a quarter-wave plate arranged at an output side of the polarization splitter so as to convert one of circularly polarized light and linearly polarized light to the other of circularly polarized light and linearly polarized light; a gas cell in which metal atom vapor is enclosed; a light guide that guides light after passing through the gas cell back to the gas cell as a turned-back light; and a photodetector that detects the turned-back light, the turned-back light having been passed through the gas cell and changed the optical path by the polarization splitter. The atomic oscillator controls an oscillation frequency by using a light absorption characteristic caused by a quantum-interference effect when the two resonant light components are incident on the optical system.