1938 results about "Linear polarization" patented technology

Systems for THz transmission using new types of THz waveguides with low loss, negligible group velocity dispersion and structural simplicity are described herein. The THz system incorporates the use of a waveguide with two or more substantially parallel conductive elements which may enable many new THz sensing applications. It is now possible to direct the THz pulse inside of containers or around corners, where line-of-sight optics are not practical. Moreover, the systems allow use of either radially polarized or linearly polarized THz antennas. The disclosed systems are compatible with existing terahertz generation and detection techniques.

There is provided a device capable of switching between a state that displays a high-quality image and a mirror status in which is obtained an easy-to-view reflection image suitable for a person to view his / her own face or figure. An image display portion 1000 that emits image light 3001, reflective polarization selection means 300 that transmits a first linear polarization component emitted from the image display portion 1000 and reflects a second linear polarization component, whose polarization axis is orthogonal to that of the first linear polarization component, a transmission polarization axis variable portion 400 capable of selecting between one of a state that changes the polarization axis of incident linearly polarized light and a state that does not change the polarization axis of incident linearly polarized light, and a polarization selection member 500 which, of the incident light, absorbs the first linear polarization component and transmits the second linear polarization component, whose polarization axis is orthogonal to that of the first linear polarization component, are disposed in this order. In this case, absorbing polarization selection means 208 is disposed at the image display portion 1000, and the first linear polarization is emitted as the image light.

A compact, agile polarization diversity, multiple frequency band antenna with integrated electronics for terrestrial terminal use in satellite communications systems is disclosed. The antenna includes an antenna feed having highly integrated microwave electronics that are mechanically and electromagnetically coupled thereto in a distributed arrangement so that diverse polarization senses having a low axial ratio and electronic switching control of the polarization senses is provided. The arrangement of the integrated distributed transceiver configuration enables the mechanical rotation of the orientation of a first transceiver for skew alignment while a second transceiver remains stationary relative to the antenna feed assembly. The first transceiver can be a high-band transmitter and receiver pair that supports linear polarization senses and the second transceiver can be a low-band transmitter and receiver pair that supports circular polarization senses. The antenna system presented is highly compact and offers improved polarization performance previously achievable by only larger devices.

An apparatus and method to determine the surface orientation of objects in a field of view is provided by utilizing an array of polarizers and a means for microscanning an image of the objects over the polarizer array. In the preferred embodiment, a sequence of three image frames is captured using a focal plane array of photodetectors. Between frames the image is displaced by a distance equal to a polarizer array element. By combining the signals recorded in the three image frames, the intensity, percent of linear polarization, and angle of the polarization plane can be determined for radiation from each point on the object. The intensity can be used to determine the temperature at a corresponding point on the object. The percent of linear polarization and angle of the polarization plane can be used to determine the surface orientation at a corresponding point on the object. Surface orientation data from different points on the object can be combined to determine the object's shape and pose. Images of the Stokes parameters can be captured and viewed at video frequency. In an alternative embodiment, multi-spectral images can be captured for objects with point source resolution. Potential applications are in robotic vision, machine vision, computer vision, remote sensing, and infrared missile seekers. Other applications are detection and recognition of objects, automatic object recognition, and surveillance. This method of sensing is potentially useful in autonomous navigation and obstacle avoidance systems in automobiles and automated manufacturing and quality control systems.

A plant for generation of information indicative of the depth and the orientation of an object positioned below the surface of the ground is adapted to use electromagnetic radiation emitted from and received by an antenna system associated with the plant. The plant has a transmitter and a receiver for generation of the electromagnetic radiation in cooperation with the antenna system mentioned and for reception of the electromagnetic radiation reflected by the object in cooperation with the antenna system, respectively. The antenna system includes a plurality of individual antenna elements such as dipole antennas, having substantially linear polarization. The antenna elements are positioned in relation to the geometric center of the antenna system, with the various centers of the antenna element displaced in relation to the geometric center of the antenna system. The plant has a mechanism for rotating the antenna system and thus polarizing the electromagnetic field around or in relation to the geometric center of the antenna system.

A half-wave printed “patch” antenna includes, symmetrically with respect to a plane of symmetry of the antenna perpendicular to faces of the antenna, a dielectric substrate and two conductive layers on respective faces of the substrate. One face of the substrate includes a raised portion extending lengthwise of the plane of symmetry and one of the conductive layers extends over and along said raised portion. Consequently, the antenna has a small size, combined with a more open radiation diagram. The antenna includes only one raised portion for linear polarization, or two raised portions or a raised portion with axial symmetry for crossed polarizations.

A sensor chip has a metal layer formed on a surface of a substrate, where a plurality of microscopic concave part is formed in a measurement region of the surface of the metal layer. When light of linear polarization is irradiated onto the measurement region, local resonance electric field generates at opposing metal layer surfaces in the concave part. The reflected light thereof is received to measure reflectance. The light of linear polarization is irradiated so that the polarizing surface becomes orthogonal to the longitudinal direction of the concave part.

A device (100, 140, 150) for differentially absorbing light, depending on the state of linear polarization of the light, is disclosed. This polarizing effect is induced and controllable by the level of ambient light impinging on the device. The device (100, 140) may be used as an anti-glare vision protection device which selectively absorbs specularly reflected sunlight in brightly lit environments while permitting all light to pass in dimly lit environments. The device (100) includes a carrying medium which may be a film (142) or opposed substrates (112) that are sealed. A film or the opposed substrates carry a mixture (120) of fluid material (124) and photochromic dyestuffs (122), wherein the photochromic material is activated upon the detection of ultraviolet light so as to absorb some of the light and wherein the energization of the photochromic material effects the material so as to simultaneously selectively absorb the specularly reflected sunlight. The material (124) may be any fluid that dissolves the photochromic dyestuff material (122). The fluid is preferably a liquid crystal material such as nematic or chiral nematic. Alternatively, the material (124) may be a polymer liquid crystal. The device (150) may allow for electrical control of the absorptive properties.

Provided are a view angle control element, which limits a view angle without deteriorating image qualities (front qualities) when viewed from the front, and a display device provided with such view angle control element. A liquid crystal display device (1) is provided with a liquid crystal panel (10), and a view angle control film (20) for controlling the view angle of the liquid crystal panel (10). The view angle control film (20) is a laminated film having at least a liquid crystal film (21) and a linear polarization plate (22). In the liquid crystal film (21), liquid crystal molecules are solidified by being arranged with the long axis inclined in a prescribed azimuth direction from the normal line direction of the film surface. The linear polarization plate (22) of the view angle control film (20) and the linear polarization plate (14) of the liquid crystal panel (10) are arranged so that the polarization transmission axis is arranged to cross the long axis direction of the liquidcrystal molecule when viewed from the normal line direction.

Radio Frequency Identification (RFID) antennas systems and methods that are less sensitive to orientation. One example includes an interrogator having a radio frequency transceiver, a first linearly polarized antenna in electrical communication with the transceiver, and a second linearly polarized antenna in electrical communication with the transceiver, the second antenna having a polarization in a direction substantially perpendicular to the first antenna; a control circuit is in electrical communication with the transceiver and with the first and second antennas, the control circuit operable to switch between interrogating with the first antenna and interrogating with the second antenna, and an RFID decoder is coupled to an output of the transceiver to decode an interrogated electromagnetic signal from a tag.

A method and system for communicating state information from a transponder to a reader. The transponder outputs linearly polarized RF signals having either a first polarization, such as horizontal, or a second polarization, such as vertical. The polarization is selected so as to indicate a first state or a second state. The reader detects whether received RF signals have the first polarization or the second polarization, and thereby determines the state of the transponder. In some embodiments, the reader may include two linearly polarized antennas, one with the first polarization and one with the second polarization, for receiving the RF signals from the transponder and determining the polarization of the received RF signals. The system may be implemented within an electronic toll collection system, wherein the transponders are affixed to the interior of vehicle windshields using a rotatable mounting mechanism having two selectable positions.

An antenna device with an adaptive polarization switching function, the antenna device including an antenna array comprising a first linear polarization antenna and a second linear polarization antenna, the first linear polarization antenna and the second linear polarization antenna having polarization directions orthogonal to each other, and a feeding unit comprising an input terminal for receiving a transmission signal, a first output terminal coupled to the first linear polarization antenna, and a second output terminal coupled to the second linear polarization antenna, wherein the feeding unit distributes energy of the transmission signal to the first output terminal and the second output terminal according to a control signal so as to generate feeding signals of the first linear polarization antenna and the second linear polarization antenna and to make the feeding signals have a phase difference.

Systems and methods are disclosed for providing a linear polar transmitter. The systems and methods may include generating an input amplitude signal and an input phase signal, where the input amplitude signal and the input phase signal are orthogonal components of an input signal, and where the input amplitude signal and the input phase signal are generated on respective first and second signal paths. The systems and methods may also include processing the input amplitude signal along the first signal path using an amplitude error signal to generate a predistorted amplitude signal, and processing the input phase signal along the second signal path using an phase error signal to generate a predistorted phase signal. The systems and methods may also include providing the predistorted amplitude signal along the first signal path and the predistorted phase signal along the second signal path to a power amplifier to generate an output signal, where the amplitude error signal is generated from a comparison of at least an amplitude portion of the output signal with the predistorted amplitude signal and where the phase error signal is generated from a comparison of at least a phase portion of the output signal with the predistorted phase signal.

The invention provides a large diameter aspheric measuring device based on ultra-precision rotary scan and a method, belongs to the macroscopic measuring technology. The device comprises an ultra-precision air flotation turntable, a precision angle and angle measuring system, an ultra-precision linear air flotation guide, a length-measuring device and a gradient measurement system. The gradient measurement system comprises a linear polarization He-Ne laser or a semiconductor laser, a diffraction element, a scanning head and an image receiving unit. The linear polarization He-Ne laser or the semiconductor laser and the image receiving unit are separately fixed on the two sides of the base beam. The scanning head is fixed on the ultra-precision linear air flotation guide. The scanning head comprises a radial gradient measurement sub-scanning head and a tangential gradient measurement sub-scanning head, both of which comprise an error compensation light path. The working platforms of the two sub-scanning heads are orthogonal to each other. The invention discloses a large diameter aspheric measuring method based on ultra-precision rotary scan.

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.

The invention provides a low-profile circular-polarization antenna that can be implemented at a reduced mounting cost of components. Two linear-polarization surface-mount antennas are mounted on a mounting substrate such that their planes of polarization are perpendicular to each other in the direction normal to the mounting surface, and an amplification circuit, a shield case for covering the circuit, and a phase circuit for sending signals having the same amplitude and a phase difference of 90 degrees to the two surface-mount antennas are provided on the same mounting surface.

A new VCSEL design is presented to achieve high output power and high brightness with a strong selection of a linear polarization state in high speed pulsing operation. Higher output power is achieved by including multiple gain segments in tandem, in the gain region. To achieve single mode operation with high output power, an extended cavity three reflector design is presented. High degree of polarization selectivity is achieved by a linear grating deployed with the third reflector, such that lasing is allowed only in a preferred linear polarization state. A polarization selective reflector including a linear grating is designed to impart strong polarization selectivity for a preferred linear polarization state. The polarization selective reflector used as the third reflector in an extended cavity VCSEL device, exhibits strong polarization selection for a preferred linear polarization state during high speed pulsing including in the gain switching resonance regime.

The invention relates to a polarization conversion method based on artificial electromagnetic materials. Electromagnetic waves are controlled to be spread in the artificial electromagnetic materials which constitute a polarization converter by designing the structure of the artificial electromagnetic materials, thereby leading the relation of the transmission coefficients of an electric field in the different directions to achieve the conversion from one incident wave polarization state to another emergent wave polarization state in a plane which is perpendicular to the wave spread direction, the relation of the transmission coefficients needs to be met is as follows: if the spread direction of the electromagnetic waves is defined as an X axis of a three-dimensional rectangular coordinate, the electric field E is decomposed to two electric field components of Ey and Ez which are mutually perpendicular, E is equal to yEy plus zEz, the transmission coefficients of T<y> and T<z> of the electric field in the two directions which pass the materials that constitute the polarization converter meet the following conditions: 1) for the situation of converting the incident waves with any polarization state to the emergent waves with the linear polarization, the absolute value of T<y>\the absolute value of T<z> is equal to p multiplied by the absolute value of Ez\the absolute value of Ey; ang(T<y>) minus ang(T<z>) is equal to plus or minus n pai minus (ang(Ey) minus ang(Ez)); wherein, n is equal to 0, 1, 2,..., p is the tangent value of an included angle theta between the linear polarization direction of the emergent waves and a z axis, p is not less than 0 and not more than 1, ang(T<y>) and ang(T<z>) represent the relative phases of T<y> and T<z>, ang(Ey) and ang(Ez) represent the relative phases of Ey and Ez. The polarization conversion method has the advantages of low cost, low energy consumption, high efficiency and compact structure.

An optically pumped magnetometer having a single optical axis using atomic electron spin or nuclear spin includes a detection unit configured to detect an angle of a polarization plane of probe light having components of linear polarization and a modulation unit configured to apply a modulation to the angle of the polarization plane of the probe light having the components of linear polarization. The modulation unit is configured to control an offset in applying the modulation to the angle of the polarization plane of the probe light having the components of linear polarization according to the angle of the polarization plane of the probe light detected by the detection unit.

Quantum resonance fluorescent microscope systems for detecting component substances in a specimen are described. The systems are based on exciting the sample containing the material with a femtosecond to nanosecond probe pulse of collimated light, which is tailored to optimize detection of a given material by separating the probe pulse into component features of frequency, polarization, phase and / or amplitude. The component features are independently shaped and formed into a composite pulse selected to optimize a signature response pulse received from the material. In some cases, two independently re-shaped pulses are combined, where one re-shaped pulse has two mixed polarization states and the other re-shaped pulse is linearly polarized. These two pulses are made to intersect at an angle of 90 degrees so that the combined pulse has electric field in each of the XYZ axes. Selection of the appropriate shapes for the component features of the pulses for a given material is accomplished by testing variations in the features on the material, assigning a fitness value to variants that tend to optimize a distinctive spectral response from the material, and using a genetic algorithm to select the combination of component features that enhances the distinctiveness of the response received over a typical background.

A system for duplex transmission and reception utilizing circular polarization wherein a pair of linear polarized orthogonal antennas is coupled to a transmitter through a hybrid coupler and a receiver is coupled to the antennas via the same hybrid coupler by using the port isolated from the transmitter. The hybrid may be a quadrature hybrid coupler or may comprise a 180 degree hybrid combined with a 90 degree phase shift network. Embodiments are shown for receiving a first reflection (opposite handed sense) circular polarized wave and alternatively, for receiving a second reflection (same handed sense) (multi-path) circular polarized wave.

A liquid crystal display apparatus, provided with liquid crystal compensation plates and λ / 4 plates on both sides of a liquid crystal cell, in a sequence that the liquid crystal compensation plates, then the λ / 4 plates. Further provided is Rth compensation film between the λ / 4 plate and linear polarization film. Set substantially at zero is a retardation Rth1 in a perpendicular direction in a range from the linear polarization films to the λ / 4 plates, excluding the λ / 4 plates. This gives a retardation (in a perpendicular direction) for optically compensating the liquid crystal cell a closer position to the liquid crystal cell. As a result, a broad angle of visibility can be maintained, without losing a balance between viewing angle characteristics from the above position (or the bottom position) and those from the right position (or the left position), while it is possible to prevent contrast ratio in a front direction from being lowered. Therefore, an LCD having good display quality can be realized.

An FM-NMOR magnetometer and concomitant magnetometry method comprising providing a linearly-polarized pump beam generator, employing a center wavelength approximately equal to a center wavelength of hyperfine peaks, and employing a modulation amplitude in the range HFS-3×LW to HFS.

An antenna switching arrangement with a quadrature arrangement of transmission lines through which a desired signal path may be configured via switches selectively grounding junctions of the switching arrangement. The desired path routing a signal from an input port to one or both of first and second output ports to generate a signal with vertical linear polarization, horizontal linear polarization or circular polarization. The selected polarization may be changed as desired and / or multiple antenna switching arrangements applied to enable simultaneous signals with different polarizations.

A direction of a power feed patch relative to a rod-shaped antenna is set so that a short axis thereof substantially orthogonally crosses a plane containing an intersection between the short axis and a long axis of the power feed patch of a patch antenna and an axis of the rod-shaped antenna. As a plane of polarization of a linearly polarized electromagnetic wave radiated from the rod-shaped antenna is thereby caused to substantially coincide with a direction of the long axis of the power feed patch and to substantially orthogonally cross a direction of the short axis, even if a powerful wave of a higher frequency than a desired frequency to be received by the patch antenna and difficult to be removed by a band pass filter of a low-noise amplifier circuit is radiated from the rod-shaped antenna, field components of the high frequency electromagnetic wave in the direction of the short axis will become virtually zero.

A concealing structure to at least partially conceal a sensor, light emitter or other component by at least partially preventing reflection of external light by an underlying structure. In some examples, this function is performed by a two-component masking assembly, the masking assembly including a linear polarizer to cause linear polarization of light which passes from the exterior of the device to an underlying component, and a wave plate to shift the axis of any reflected polarized light. In many cases, a high density optical fluid will further be included within the masking assembly to minimize reflections from the other components of the assembly.

A multi-energy polarization imaging method consisting of a multi-fusion, dual-rotating retarder / multiple-energy complete Mueller matrix-based polarimeter and dual-energy capabilities, has been invented. The term multifusion describes the use of several imaging functions altogether such as polarimetric imaging, dual-energy subtraction, multifocal imaging and other. By substracting polarimetric parameters such as degree of polarization, degree of linear polarization, degree of circular polarization, respectively, obtained with interrogation light beams of wavelengths λ1 and λ2, he system, enhanced imaging is obtained. The system includes a light source for illuminating a target with a first quantity of light having a first wavelength and a second quantity of light having a second wavelength, the first and second wavelengths being different. A polarization-state generator generates a polarization state for each of the first and second quantities of light, and includes a first polarizer through which the first and second quantities of light are transmitted before entering a first waveplate. A polarization-state receiver evaluates a resulting polarization state of the first and second quantities of light following illumination of the target, the polarization-state receiver including a second waveplate through which the first and second quantittes of light are transmitted before entering a second polarizer. An optical image-capture device captures a first image of the target illuminated by the first quantity of light and a second image of the target illuminated by the second quantity of light. A processing unit assigns a weighting factor to at least one of the first and second images and evaluates a weighted difference between the first and second images to generate a multi-energy image of the target.

A simple RF system tracks a missile, bullet or artillery round and determines the instantaneous attitude of the spinning projectile while in flight. The system is particularly useful in command-guided weapons systems where line-of-sight is maintained from the launch platform to the target. The system includes a first pair of linearly polarized transmit antennas spaced apart on the projectile for transmitting a signal and a harmonic of that signal. A receiver on the launch platform determines the roll angle and either the yaw or pitch angle from the received signals. To determine the remaining angle, either the receiver samples the received signals ninety degrees out of phase or a second pair of transmit antennas are mounted on the projectile, preferably ninety degrees from the first pair, for transmitting another pair of harmonic signals.