485 results about "Corner reflector" patented technology

A parameter measurement device of optical system comprises a short coherent light module, a focusing lens, a collimation lens, a filtering pinhole, a splitter, a corner reflector, an one-dimension accurate mobile station, an adjustable focus telescope, a micro swivel, a focusing lens and an imaging CCD. And a relative measurement method uses optical interferometry to accurately measure the eccentricity, inclination, lens thickness and lens distances of an object optical system. The invention can improve the eccentricity measurement accuracy of lens to match higher eccentricity demand, realize the final measurement of internal distances in optical system and realize the distance of assembled optical system.

The invention discloses a rotary Fourier transform interference imaging spectrometer, which includes a front collimation objective, a cube corner reflector, a beamsplitter, a rear imaging objective, a detector and a control and processing module, aims to reduce the light energy loss of a target, and has the characteristics of high luminous flux and detection sensitivity. The traditional rectilinear motion scanning manner of a moving mirror is substituted by the rotary scanning manner of the beamsplitter or the cube corner reflector, so as to avoid series of technical difficulties brought by precise rectilinear scanning of the moving mirror; a lateral shear interferometer based on the Michelson interference principle is adopted, and the characteristic of common path is obtained, so that the interference effect cannot be influenced even if the beamsplitter slightly shakes during the rotation; a planemirror in the traditional Fourier transform imaging spectrometer is substituted by the cube corner reflector, so that the problem brought by the inclined planemirror is avoided; therefore, the stability, reliability and vibration and impact resistance of the instrument are improved, and the structure of the spectrometer is more compact.

The invention relates to a double-femtosecond laser frequency comb ranging system. The double-femtosecond laser frequency comb ranging system is characterized in that a first femtosecond laser frequency comb transmits light pulses to a first frequency doubling crystal, the first frequency doubling crystal performs frequency doubling and transmits the two light pulses to a first light splitter, and the light pulses reflected by the first light splitter are transmitted to a light splitter through a first corner reflector and the first light splitter; the light pulses transmitted by the first light splitter are reflected to the light splitter through a second corner reflector and the first light splitter; a second femtosecond laser frequency comb transmits light pulses to a second frequency doubling crystal, and the second frequency doubling crystal performs frequency doubling and transmits the two light pulses to the light splitter simultaneously; the light pulses transmitted by the light splitter are mixed with light pulses emitted by a Michelson interference system, fundamental frequency light pulses of the mixed light pulses are transmitted to a first photoelectric detector through a color selective mirror, frequency doubling light pulses are reflected to a second photoelectric detector, the first photoelectric detector and the second photoelectric detector are connected to a central processing unit through an analog to digital (A/D) acquisition card, and the central processing unit processes signals to obtain a distance measuring value. The double-femtosecond laser frequency comb ranging system is widely applied to laser absolute distance measurement.

The invention discloses mid-infrared spectroscopy-based trace gas detection method and device combining a long-optical-path open light path with a wavelength modulation technique. The detection device mainly consists of a continuous wave quantum cascade laser (CW-QCL), a laser driving and controlling unit, a plane mirror, a beam splitter, a visible laser, a reference gas pool, mercury, tellurium and cadmium (MCT) detector, an off-axis parabolic mirror, a corner reflector, a digital lock-in-amplifier and a computer. By using the CW-QCL as a light source, long-optical-path open light path is combined with the wavelength modulation technique to detect multi-component trace gas with high sensitivity.

A survey apparatus includes a guide light emitting optical system emitting a fan-like visible laser light elongated in upward and downward directions as a guide light, a cylindrical part having a scanning optical system searching a corner reflector provided on a survey pole and a ranging optical system measuring a distance to the corner reflector, a driving part rotating the cylindrical part about a vertical axis in a horizontal direction and rotating the cylindrical part about a horizontal axis, and an angle measurement part measuring a direction of the cylindrical part. The guide light emitting optical system is rotated about the vertical axis in a horizontal direction integrally with the cylindrical part.

The invention relates to an airborne SAR radiation external calibration processing method based on weak arrangement of corner reflectors. The method comprises the following steps: obtaining original SAR image data of a calibration field; on the basis of a point target radar equation, reconstructing an radiation external calibration equation; performing stable estimation on calibrator image energy and geometric optical solution on a calibration RCS; carrying out fitting and correcting on a radar system transfer function to obtain preliminary radiation calibration SAR image data; carrying out the stable estimation on the calibrator image energy and the geometric optical solution on the calibration RCS; and estimating a system constant item so as to generate calibration data and obtain final radiation calibration SAR image data. According to the invention, on the basis of the point target radar equation, according to the characteristic of parameters of a radar system, the SAR radiation external calibration equation comprising a change system transfer function and a constant system constant item is reconstructed, the application process of radiation external calibration is simplified, and the problem is avoided that it is quite difficult for airborne SAR flight to obtain a large-scope homogeneous stable tropical rainforest area frequently used by similar spaceborne SAR radiation calibration.

The invention provides a simplified multiplexing white light interference fiber sensing demodulating device, which comprises a single-fiber two-way optical transmitting/receiving module, an optical fiber resonant cavity, a single-mode transmission fiber, and an optical fiber sensing array, wherein the single-fiber two-way optical transmitting/receiving module is composed of a semiconductor light source as the transmitting terminal, a semiconductor photodetector as the receiving terminal and related devices packaged together; and an optical fiber annular cavity is composed of an optical fiber coupler, an optical fiber self-focusing lens and a movable corner reflector. The device can achieve enquiry and measurement of a plurality of optical fiber sensors by embedding the single-fiber two-way optical transmitting/receiving module and the optical fiber resonant cavity in the single-mode optical fiber, and has the advantages of simple structure, easy implementation, no length restriction of the transmission cable, no influence caused by the external environment, and good stability and reliability. The device can be used for the measurement of physical quantities such as distributed deformation, strain and temperature, and can be used for multi-task sensing, multi-element sensing, local strain sensing, large-scale deformation sensing, etc.

The invention relates to a composite wave interferometry ranging distance system with two femtosecond laser frequency combs. The composite wave interferometry ranging distance system is characterized in that a first femtosecond laser frequency comb emits an optical pulse to a first spectroscope, the optical pulse reflected by the first spectroscope is transmitted to a first corner reflector, and the optical pulse reflected by the first corner reflector is transmitted to a second spectroscope through the first spectroscope. The optical pulse transmitted by the first spectroscope is transmitted to a second corner reflector, and the optical pulse reflected by the second corner reflector is reflected to the second spectroscope through the first spectroscope. A second femtosecond laser frequency comb emits an optical pulse to the second spectroscope, the optical pulse transmitted by the second spectroscope and an optical pulse emitted by a Michelson interference system are mixed and transmitted to a third spectroscope, the optical pulse transmitted by the third spectroscope is received by a first photoelectric detector in a detection mode through a first narrow-band band-pass filter, and the optical pulse reflected by the third spectroscope is received by a second photoelectric detector in a detection mode through a second narrow-band band-pass filter. The first photoelectric detector and the second photoelectric detector are connected with an A/ D converter connected with a signal processing unit through a corresponding data interface to process the received signal to obtain the required distance measuring value.

The invention provides an optical remote sensing satellite rigorous imaging geometrical model building method. The optical remote sensing satellite rigorous imaging geometrical model building method comprises the following steps that the geometrical relationship between the image point coordinates of an optical remote sensing satellite and the satellite is determined according to design parameters and on-orbit calibration parameters of an optical remote sensing satellite camera and the installation relation of the camera and the satellite; the shooting position of a satellite image is determined according to the GPS carried by the optical remote sensing satellite, the observation data of a laser corner reflector and the installation relation of the laser corner reflector and the satellite; the shooting angle of the satellite image is determined according to a star sensor carried by the optical remote sensing satellite and the observation data of a gyroscope and the installation relation of the gyroscope and the optical remote sensing satellite, a collinearity equation of all image points of the optical remote sensing satellite is built, and a rigorous imaging geometrical model of optical remote sensing satellite images is formed. The optical remote sensing satellite rigorous imaging geometrical model building method is the basis of optical remote sensing satellite follow-up geometrical imaging processing and application.

The invention discloses a parallel adjustment system of emission and receiving light paths of laser radar and a method. The system comprises a laser fixedly arranged on the tube of a receiving telescope and having the direction of the emission light parallel to the optical axis direction of the telescope, and a connection mirror, a total reflection mirror and an angle reflector consisting of a pair of right-angle prisms arranged in front of the tube of the receiving telescope, which are arranged in the optical path in front of the laser. The laser beam emitted from the angle reflector enters the tube of the receiving telescope and focuses on a combined focal plane of the primary mirror and the secondary mirror of receiving telescope. The focusi laser spot forms an image on a CCD after turning the direction through a 90-DEG turning mirror, and the clear laser spot image can be viewed on a monitor. The parallelism of the optical paths can be determined and adjusted according to the shape of the laser spot. The invention has the advantages of simple structure and higher accuracy, and has been successfully applied in developed laser radar system.

The invention provides a multi-polarization SAR compact polarimetry calibration method which comprises a calibration field compact polarimetry SAR data preprocessing process and a polarization distortion parameter calibration process. In the calibration field compact polarimetry SAR data preprocessing process, compact polarimetry SAR data radiation correction and Faraday rotation correction are mainly completed. In the polarization distortion parameter calibration process, four different types of common corner reflectors are used as reference calibrators, and a compact polarimetry calibration method (namely, a compact polarimetry polarization distortion parameter calibration method) is deduced based on a calibration model. Through the method, a polarization distortion parameter can be calibrated precisely. The calibration algorithm does not depend on the absolute RCS values of the corner reflectors, and calibration error caused by RCS inconsistency of different corner reflectors can be avoided effectively. The algorithm is of high robustness and practicability.

A tracking system uses a road mounted microwave reflector as an alignment tool. The system can be used to provide primary or supplemental guidance and alignment for an self-driving vehicle, or it can be used to provide warning signals for a manually controlled vehicle. The disclosed reflector is economical and easily installed. A preferred corner reflector contains both a microwave retro reflector and an embedded tuned circuit. The system is optimized to operate reliability and accurately in conditions of inclement weather and poor visibility, particularly where GPS signals, conventional road markers and visual aids fail.

The present invention relates to a method for correcting environmental influences at slope deformation monitoring on the basis of a corner reflector belonging to the technical field of ground-based radar monitoring. The method includes the steps as follows: performing calibrating, focusing, interfering and difference handling for radar monitoring data of the corner reflector and a target point so as to acquire displacement values of the corner reflector and the target point; acquiring a Voronoi diagram according to a Thiessen polygon rule; acquiring a geometric position relationship of the target point and the corner reflector point closest the target point; subtracting the acquired displacement of the corner reflector closest the target point according to the acquired displacement of the target point; performing environmental influence correction for the target point by utilizing single corner reflector so as to acquire the effective displacement of the target point; performing weight configuration according to the geometric position relationship of the corner reflector point and the target point when a great error exists after the correction of the single corner reflector; and performing environmental influence correction by utilizing a manner of weighted average of the corner reflectors. The method can efficiently correct environmental influences by combining the ground-based radar interferometry principle with the Thiessen polygon rule.

The present invention relates to a polarimetric calibration technique based on natural distribution scenes and a rare calibrator, which is used for the calibration and correction of distorted polarimetric synthetic aperture radar (SAR) data. The present invention breaks the calibration bottleneck of domestic machine-borne polarimetric SAR data, and develops a technique which utilizes widely distributed natural ground objects for the crosstalk calibration of polarimetric data without the help of an artificial corner reflector and needs only one or a small amount of triple-sided corner reflectors for the calibration of the imbalance of polarimetric receiving channels. In addition, the technique uses the strength change of natural ground object scenes with wide similar radar backward scattering properties in the distance direction to fit out an antenna directional pattern, and fully utilizes polarimetric ground object information to correct all the polarimetric SAR channel data with the same antenna directional pattern, thereby retaining the polarimetric scattering characteristics of ground object targets before and after correction.

The invention relates to the field of mounting calibration of vehicle-mounted millimeter-wave radars, in particular to a calibration device for mounting positions of vehicle-mounted millimeter-wave radars and a calibration method thereof. The calibration device comprises a radar which is arranged on a vehicle and a calibration target group which is arranged in front of the radar and is used for determining a mounting position of the radar, wherein the calibration target group comprises a base and multiple groups of support rods which are arranged on the base; and a corner reflector capable ofreflecting millimeter waves is arranged on each group of support rods. The calibration method specifically comprises the following steps of: S1, positioning, S2, calibration, S3, information transmission, S4, comparison, S5, correction, and S6, calibration. The calibration device and the calibration method can be widely applied to the offline mounting calibration of vehicles equipped with vehicle-mounted millimeter-wave radars so as to improve the radar mounting precision, ensure the radar detection performance and ensure the vehicle running safety.

The invention discloses a laser radar coaxial detection system and an automatic calibration method therefor, and the system comprises an industrial control computer, a laser, a beam expanding lens (1), a double-optical-wedge adjuster (2), a 45-degree plane reflector (3), a 45-degree plane reflecting prism (4), a corner reflector (5), a receiving telescope (6), an aperture diaphragm (7), a collimating mirror (8), and a CCD camera. The laser is controlled by the industrial control computer to emit a laser beam with certain energy, and the laser beam sequentially passes through the beam expanding lens (1), the double-optical-wedge adjuster (2), the 45-degree plane reflector (3) and the 45-degree plane reflecting prism (4). A light beam signal reflected by the corner reflector (5) passes through the receiving telescope (6) to be focused on the aperture diaphragm (7), and then passes through the collimating mirror (8) to be received by the CCD camera. The system employs target calibration, and the signal is received by the CCD camera. A deflection angle value is calculated through a formula, and is fed back to a computer for controlling the double-optical-wedge adjuster (2) to carry out angle adjustment. The system is convenient, is not affected by an external environment, shields human errors through employing the digitalization technology, and can obtain higher precision.

The invention provides a corner reflector which comprises a triangular supporting pedestal, a corner reflector body, and a pitching adjustment mechanism. The triangular supporting pedestal comprises three supporting foundations, a first support, a second support, a third support and a rotating shaft, wherein either two of the three supporting foundations are fixed via angle iron, the first, second and third supports are respectively fixed on the corresponding supporting foundations, and extend upwards along the horizontal plane, and the two ends of the rotating shaft are respectively pivoted to the upper ends of the first and second supports. The corner reflector body is of a triangular cone structure, the bottom surface of the corner reflector body is fixed on a rotating shaft of the pedestal via a welding clamping block, the two side surfaces of the corner reflector body are arranged symmetrically, and multiple pitching adjustment support lugs in different heights are arranged at a connecting position, at the back of the corner reflector body, of the two side surfaces. One end of the pitching adjustment mechanism is hinged to the third support of the triangular supporting pedestal, and the other end of the pitching adjustment mechanism is hinged to one of the multiple pitching adjustment support lugs at the back of the corner reflector body. In the corner reflector, the pitching adjustment support lugs in different heights are used to realize flexible pitching adjustment of the corner reflector body.

The invention discloses a portable differential spectrum absorbing method and device, where to-be-tested gas is charged in a multiple reflecting tank, the light emitted from a light source is gathered by lens to enter the multiple reflecting bank to be reflected many times in the multiple reflecting bank and then be led through optical fiber into a spectrum meter by the actions of lens and optical fiber coupler, and then the spectrum meter makes spectrum signal conversion, and finally transmits the converted signal to a computer. And the invention replaces open light path with multiple reflecting bank to complete monitoring polluted gas in atmosphere without telescope and angle reflector.

For a method fabricating a dihedral corner reflector array optical element, a molding die having a reversal shape of the prism bodies is used. Each prism body has a frustum shape having an end plane whose area is smaller than that of the base plane side of the substrate. Each prism body is composed of a rectangular parallelepiped portion including the orthogonal plane sides to be a dihedral corner reflector and a taper portion integrated therewith having sides being non-parallel to the orthogonal plane sides. The method includes clamping the molding die to define a cavity therein; forming the optical element made from molten resin in the cavity; and parting the optical element from the molding die. The molding dies are relatively moved in a parting direction that the molding die leaves the orthogonal plane sides before anything else to part the optical element.

Radar reflective rescue and safety devices comprise radar permeable coverings around a plurality of reflectors. The radar reflective material may be incorporated into inflatable life vests or foam filled life vests. Additionally, inflatable life rafts with radar reflective cells are able to help personnel lost at sea to be found by radar. The radar reflective cells may also be incorporated into an inflatable cylindrical tube as radar cross-section enhancer separate from other flotation devices. The reflectors are flexible metallic material that forms reflective cavities once the shell is inflated. The reflective cavities may appear as flat surfaces, tilted surfaces, corner reflectors or some combination thereof depending upon the orientation of the cavities to an incident radar wave.

The invention discloses an automatic light beam capturing device, which comprises an optical antenna connected with an automatic tracking system. A Brewster window and a corner reflector are arranged on the emergent light side of the optical antenna. A focusing lens and a signal detector are arranged on the reflected light side of the Brewster window. A position-sensitive detector is arranged on the emergent light side of the Brewster window and is communicated with the automatic tracking system through a feedback channel. The light beam capturing method comprises that the optical antenna injects light signals to the corner reflector through the Brewster window after the optical antenna focuses the light signals; the corner reflector reflects the received light signals to the Brewster window, the reflected light is downward projected onto the position-sensitive detector, the Brewster window reflects partial light to the focusing lens and the light signals are received through the detector; and the position-sensitive detector calculates to obtain the position information of light, the position information is fed back to the automatic tracking system, and the automatic tracking system adjusts the transmitting direction and the pitch angle of the optical antenna. Since the invention combines an ATP with a signal laser, the invention has the advantages of simple structure, high economy and high feasibility and the device is suitable for ground atmosphere laser communication systems.

The invention relates to angle-limiting optical reflectors and optical dispersive devices such as optical spectrum analyzers using the same. The reflector has two reflective surfaces arranged in a two-dimensional corner reflector configuration for reflecting incident light back with a shift, and includes two prisms having a gap therebetween that is tilted to reflect unwanted light and transmit wanted light. A two-pass optical spectrum analyzer utilizes the reflector to block unwanted multi-pass modes that may otherwise exist and degrade the wavelength selectivity of the device.