Showing papers on "Waveplate published in 2013"
TL;DR: Here it is able to theoretically and experimentally demonstrate that broadband, strong polarization conversion and quarter-wave plate functionality may be achieved using a single, ultrathin planar metasurface in the visible regime.
Abstract: The response of optical metasurfaces is usually narrowband, and mechanisms to increase their bandwidth often clash with causality and passivity constraints of materials. Here we are able to theoretically and experimentally demonstrate that broadband, strong polarization conversion and quarter-wave plate functionality may be achieved using a single, ultrathin planar metasurface in the visible regime. Our realized sample is based on interleaved silver nanorods with properly tailored frequency dispersion that introduce an abrupt flat 90° phase shift for orthogonal polarizations over a thickness of few tens of nanometers, achieving achromatic quarter-wave plate behavior covering a good portion of the visible spectrum. Analogous design principles are extended to cover the entire visible spectrum and beyond.
302 citations
TL;DR: In this article, an anisotropic meta-mirror for achromatic polarization tuning was proposed and experimental results showed that linear polarized wave can be achromatically transformed to its cross-polarization state or to arbitrary circular polarization after its reflection from the mirror.
Abstract: Polarization states are of particular importance for the manipulation of electromagnetic waves. Here, we proposed the design and experimental demonstration of anisotropic meta-mirror for achromatic polarization tuning. It is demonstrated that linear polarized wave can be achromatically transformed to its cross-polarization state or to arbitrary circular polarization after its reflection from the mirror. Microwave experiments verified that the fraction bandwidth for 90% transformation efficiency can be larger than 3:1. Furthermore, by utilizing photoinduced carrier generation in silicon, a broadband tunable circular polarizer is demonstrated in the terahertz regime.
155 citations
TL;DR: In this article, a dual-wavelength wave plate between the non-linear optical crystal and the plasma was used to enhance the terahertz field in an air plasma produced by two-color laser pulses.
Abstract: We introduce a simple and efficient method of enhancing the terahertz field in an air plasma produced by two-color laser pulses, by inserting a specially designed dual-wavelength wave plate between the non-linear optical crystal and the plasma. Adjusting the polarization of the two laser pulses yielded an electric field of 1.4 MV/cm, which was 1.7 times as intense as that obtained from the unmodified system. Additionally, taking a dispersion of the group velocities of the two-color laser pulses into account, we discussed the validity of the enhancement factor.
64 citations
TL;DR: Numerical simulation results show that an Au quarter-wave plate designed in this Letter can efficiently convert a linearly polarized light at normal incidence into circularly polarized light, whose ellipticity is 0.994 at an operating wavelength of 1550 nm.
Abstract: Based on an analysis of the surface admittance of a plasmonic film with a substrate, we propose an ultrathin quarter-wave plate consisting of a periodic plane array of symmetrical L-shaped plasmonic antennas. The period, which determines the coupling among L-shaped antennas, is an important parameter for optimizing the performance of the structure. Numerical simulation results show that an Au quarter-wave plate designed in this Letter can efficiently convert a linearly polarized light at normal incidence into circularly polarized light, whose ellipticity is 0.994 at an operating wavelength of 1550 nm. The thickness is only 30 nm, which is nearly 1/50 of the wavelength of incident light.
54 citations
TL;DR: The results of calculation and experimental testing of an achromatic polarization converter and a composite terahertz waveplate, which are represented by sets of plane-parallel birefringent plates with in-plane bireFringence axis, are presented.
Abstract: We present the results of calculation and experimental testing of an achromatic polarization converter and a composite terahertz waveplate (WP), which are represented by sets of plane-parallel birefringent plates with in-plane birefringence axis. The calculations took into account the effect of interference, which was especially prominent when plates were separated by an air gap. The possibility of development of a spectrum analyzer design based on a set of WPs is also discussed.
37 citations
Patent•
21 Aug 2013TL;DR: A flexible organic light emitting display device includes: a display panel configured to output an image; a retardation film formed on an upper portion of the display panel to cover the display panels and formed by laminating a half wave plate and a quarter wave plate; and a polarizing plate attached to the film as discussed by the authors.
Abstract: A flexible organic light emitting display device includes: a display panel configured to output an image; a retardation film formed on an upper portion of the display panel to cover the display panel and formed by laminating a half wave plate and a quarter wave plate; and a polarizing plate attached to the retardation film. A color shift in a black screen can be improved by replacing a barrier film used for face seal with a retardation film including a half wave plate and a quarter wave plate combined at a predetermined angle.
33 citations
TL;DR: In this article, the terahertz achromatic quarter wave plate is realized for the first time in the frequency band of 1.3-1.8 GHz via design, fabrication, and characterization.
32 citations
TL;DR: It is shown that MgF2 can be applied practically as a half-waveplate for the chromospheric Lyman-alpha spectro-polarimeter (CLASP) sounding rocket experiment and that the developed measurement method can be easily applied to other VUV birefringent materials at other wavelengths.
Abstract: Spectro-polarimeteric observations in the vacuum-ultraviolet (VUV) region are expected to be developed as a new astrophysics diagnostic tool for investigating space plasmas with temperatures of >10(4) K. Precise measurements of the difference in the extraordinary and ordinary refractive indices are required for developing accurate polarimeters, but reliable information on the birefringence in the VUV range is difficult to obtain. We have measured the birefringence of magnesium fluoride (MgF2) with an accuracy of better than ±4×10(-5) around the hydrogen Lyman-α line (121.57 nm). We show that MgF2 can be applied practically as a half-waveplate for the chromospheric Lyman-alpha spectro-polarimeter (CLASP) sounding rocket experiment and that the developed measurement method can be easily applied to other VUV birefringent materials at other wavelengths.
28 citations
TL;DR: The design of Stokes and Mueller polarimeters based on ferroelectric liquid crystal (FLC) panels are presented, and some experimental measurements of different Stokes vectors and Mueller matrices are provided, validating the proposed prototypes.
Abstract: We present the design of Stokes and Mueller polarimeters based on ferroelectric liquid crystal (FLC) panels. The instrument is complete and takes time-sequential measurements. A FLC device is modeled as a uniaxial birefringent waveplate with two stable optical axis orientations switchable by a squared electrical signal. The optical parameters of the LC device (retardance and the two stable orientations of the fast axis) are calibrated. Then the orientations of the optical elements of the setup are optimized in order to minimize the propagation of the noise. We also provide a tolerance study to achieve 2% accuracy for the Stokes vector and Mueller matrix metrology. These analyses are conducted as a function of the incident state of polarization and of the Mueller matrix to be measured, respectively. The optimized system is implemented and calibrated in the laboratory. We evaluate its repeatability over 24 h of operation, and the dependence with the temperature is discussed. In addition, we include a study related to the speed of taking the measurements. Finally, we provide some experimental measurements of different Stokes vectors and Mueller matrices, validating the proposed prototypes.
27 citations
TL;DR: A device that can convert linearly polarized light to light with an overall degree of polarization of 88% and a degree of circular polarization of 86% at a particular wavelength of 702 nm is demonstrated.
Abstract: Here we demonstrate the fabrication and characterization of a plasmonic wave plate. The device uses detuned, orthogonal nanometric apertures that support localized surface plasmon resonances on their interior walls. A device was fabricated in a thin silver film using focused ion beam milling and standard polarization tomography used to determine its Mueller matrix. We demonstrate a device that can convert linearly polarized light to light with an overall degree of polarization of 88% and a degree of circular polarization of 86% at a particular wavelength of 702 nm.
25 citations
TL;DR: A parallel two-step polarizing phase shifting interferometer based on a Double Cyclic Shear Interferometer (DCSI) is proposed in this paper for quantitative phase imaging and presents better stability against external configurations than other types of interferometers.
Abstract: A parallel two-step polarizing phase shifting interferometer based on a Double Cyclic Shear Interferometer (DCSI) is proposed in this paper for quantitative phase imaging. The system has the advantage of retrieving the derivative phase data map directly. Due to its configuration, it presents better stability against external configurations than other types of interferometers. The DCSI generates two π-shifted interferograms, which are recorded by the CCD camera in a single-shot. The separation between parallel interferograms can be varied in the two axes for convenience. To obtain the optical phase data map, a parallel phase shift between interferograms is obtained by rotating a half wave plate retarder. We analyzed the cases of four patterns with shifts of π/2 captured in two shots; the optical phase was processed by a four-step algorithm. Related experimental results obtained for microscopic transparent samples are presented.
Patent•
08 Aug 2013
TL;DR: In this paper, a sub-wavelength grating is placed inside a liquid crystal variable optical retarder to reduce polarization dependence of the optical retardation generated by the variable optical retraction.
Abstract: A sub-wavelength grating is placed inside a liquid crystal variable optical retarder to reduce polarization dependence of the optical retardation generated by the variable optical retarder. A small thickness of the sub-wavelength grating, as compared to a conventional waveplate, reduces the driving voltage penalty due to the in-cell placement of the sub-wavelength grating.
Patent•
08 May 2013
TL;DR: A quantum rod light emitting display device according to an aspect of the present invention includes a display panel including a quantum rod layer on which a plurality of quantum rods formed between a first substrate and a second substrate are arranged and a polarizing plate placed on the display panel and composed of a quarter wave plate (QWP) layer and a PVA layer displayed as the following chemical formula as discussed by the authors.
Abstract: A quantum rod light emitting display device according to an aspect of the present invention includes a display panel including a quantum rod layer on which a plurality of quantum rods formed between a first substrate and a second substrate are arranged and a polarizing plate placed on the display panel and composed of a quarter wave plate (QWP) layer and a PVA layer displayed as the following chemical formula1 The PVA layer transmits only light linearly polarized in a first direction and the QWP layer is placed on the bottom of the PVA layer and circularly polarizes the linearly polarized light or linearly polarizes light reflected by the display panel in a second direction According to this, as a polarizing plate including the PVA layer formed of hydrophobicity is applied, the transmittance of the plate can be improved and night visibility can be improved so that the efficiency of light from a backlight can be maximized
Patent•
14 Mar 2013TL;DR: In this article, a focus-invariant point spread function in one focal region and point spread functions that vary as a function of range within the imaged object in a different focal region are presented.
Abstract: Optical systems utilize waveplates to simultaneously encode information for increasing image depth of field and for providing a depth map of the imaged object or sample. These waveplates are configured to result in a focus-invariant point spread function in one focal region, and to result in point spread functions that vary as a function of range within the imaged object in a different focal region. For example, a basic compound microscope might have a specially shaped waveplate inserted at the back aperture plane of the microscope objective to manipulate the phase of the wavefront. An image formed on one side of the plane of best focus is focus invariant, and is brought into focus by a restoring algorithm. An image formed on the other side of the plane of best focus captures point spread functions comprising rings that vary with depth within the imaged object.
TL;DR: In this article, a plasmonic patch antenna was used to convert linear polarized light into circular polarized light in the visible range (633nm) by further exploiting the dimer patch antenna structure composed of different metals.
Abstract: A quarter-wave plate using plasmonic patch antennas has been investigated. The nanostructures can convert linear polarized light into circular polarized light in the visible range (633 nm). By further exploiting the dimer patch antenna structure composed of different metals, directional emission (with a directivity of 4.8) of circular polarized light (with a conversion efficiency of 27.8%) in an oblique direction with respect to the incident light is enabled. Compared with previous designs, the proposed structures are ultra-thin, and are more suitable for integration applications.
TL;DR: In this article, the authors proposed a technique for performing quantum state tomography of photonic polarization-encoded multiqubit states using a single rotating wave plate, a polarizing beam splitter, and two photon counting detectors per photon mode.
Abstract: We propose a technique for performing quantum state tomography of photonic polarization-encoded multiqubit states. Our method uses a single rotating wave plate, a polarizing beam splitter, and two photon-counting detectors per photon mode. As the wave plate rotates, the photon counters measure a pseudocontinuous signal which is then Fourier transformed. The density matrix of the state is reconstructed using the relationship between the Fourier coefficients of the signal and the Stokes' parameters that represent the state. The experimental complexity, i.e., different wave plate rotation frequencies, scales linearly with the number of qubits.
TL;DR: In this paper, a figure-of-eight fiber laser including a polarization-imbalanced nonlinear optical loop mirror and a Mach-Zehnder optical filter formed by two fibre tapers placed in series is studied.
Abstract: We study experimentally a figure-of-eight fibre laser including a polarization-imbalanced nonlinear optical loop mirror and a Mach–Zehnder optical filter formed by two fibre tapers placed in series. Depending on the adjustments of two wave retarders included in the setup, different modes of operation of the laser are found. In continuous-wave mode, tunable single-wavelength operation as well as multiwavelength lasing are observed. For some adjustments, self-pulsing also takes place, although the pulses are very unstable. Finally, for some adjustments a mechanical stimulation (a kick) leads to the onset of passive mode locking. Measurements reveal that the mode-locked pulses actually are noise-like pulses. Both stable fundamental mode locking and second-harmonic mode locking with particular dynamics were obtained. In this work, we analyse how simple wave plate adjustments can lead to such a variety of operational modes of the fibre laser.
Patent•
25 Dec 2013
TL;DR: In this paper, a common-path interference measurement device for the generated optical aberration of a liquid-crystal spatial light modulator is described, which is based on the utility model.
Abstract: The utility model relates to a common-path interference measurement device for generated optical aberration of a liquid-crystal spatial light modulator. The device includes a laser, a beam expander, a polarizer, a beam-splitter prism, a liquid-crystal spatial light modulator, a quarter wave plate, a polarization analyzer, an imaging lens, a CCD detector and a computer. The liquid-crystal spatial light modulator divides a beam of incident-ray polarization laser into a beam of orthogonal linear polarization test light and a beam of orthogonal linear polarization reference light, which are equal in energy. A polarization direction of the test light is parallel to a crystal-liquid optical axis of the liquid-crystal spatial light modulator and the test light includes information of the generated optical aberration of the liquid-crystal spatial light modulator. The reference light is not affected by a drive signal. The test light and the reference light pass through the beam-splitter prism, the quarter wave plate and the polarization analyzer along the same optical path and then interferences are generated. The rotary polarization analyzer acquires a four-frame phase-shifting interference figure and the optical-aberration information is restored accurately through a phase-shifting algorithm. The common-path interference measurement device for the generated optical aberration of the liquid-crystal spatial light modulator adopts a common-path self-interference structure and the device has the characteristics of being great in stability, low in cost, simple in structure and high in measurement efficiency.
TL;DR: Compared with lithium niobate crystal used as an electric-field sensor, main advantages of the BBO crystal include higher measurement sensitivity, compact configuration, and no ferroelectric ringing effect.
Abstract: A novel optical electric-field sensor is proposed and demonstrated in experiment by use of a single beta barium borate (β-BaB2O4, BBO) crystal. The optical sensing unit is only composed of one BBO crystal and two polarizers. An optical phase bias of 0.5π is provided by using natural birefringence in the BBO crystal itself. A small angle (e.g., 0.6°) between the sensing light beam and principal axis of the crystal is required in order to produce the above optical bias. Thus the BBO crystal is used as the electric-field-sensing element and quarter waveplate. The ac electric field in the range of (1.4–703.2) kV/m has been measured with measurement sensitivity of 1.39 mV/(kV/m) and nonlinear error of 0.6%. Compared with lithium niobate crystal used as an electric-field sensor, main advantages of the BBO crystal include higher measurement sensitivity, compact configuration, and no ferroelectric ringing effect.
Patent•
06 Dec 2013
TL;DR: In this article, a low-cost, high-precision three-dimensional shape measuring device using vibration-resistant phase shift digital holography was proposed, in which an object-light optical system allows object light to be incident on a polarization element for detecting relative phase differences in a first circularly polarized light state, and a reference-light light optical system allowed a reference light was used on a polarizing element to detect relative phase difference in a second circularly polarised light state in the direction opposite from the first.
Abstract: [Problem] To provide a low-cost, high-precision three-dimensional shape measuring device using vibration-resistant phase shift digital holography. [Solution] A three-dimensional shape measuring device, wherein an object-light optical system allows object light to be incident on a polarization element for detecting relative phase differences in a first circularly polarized light state, a reference-light optical system allows a reference light to be incident on a polarization element for detecting relative phase differences in a second circularly polarized light state in the direction opposite from the first circularly polarized light, and the polarization element for detecting relative phase differences transmits a component of the object light, which is the first circularly polarized light, in the polarization direction of the polarization element for detecting relative phase differences, and a component of the reference light, which is the second circularly polarized light, in the polarization direction of the polarization element for detecting relative phase differences. The polarization direction of the polarization element for detecting relative phase differences is rotated to thereby vary the relative phase difference between the object light and the reference light transmitted through the polarization element for detecting relative phase differences and to acquire a plurality of hologram images having different relative phase differences.
Patent•
22 May 2013
TL;DR: In this article, a liquid medium empty spot electric field distribution measuring device based on the Kerr effect was proposed to solve the problem that the prior liquid medium APEDD has large restrictions on the scope of externally applied voltage even dynamic measuring and real-time acquisition can be realized when liquid medium with small Kerr constant is measured.
Abstract: The present utility model relates to a liquid medium empty spot electric field distribution measuring device, especially to a liquid medium empty spot electric field distribution measuring device based on Kerr effect. The device is provided to solve a problem that the prior Liquid medium empty spot electric field distribution measuring device has large restrictions on the scope of externally applied voltage even dynamic measuring and real-time acquisition can be realized when liquid medium with small Kerr constant is measured. A laser beam emitted by a laser enters into a light incident end of a beam expanding lens, the laser beam enters into a light incident end of a collimator through a light exit end of the beam expanding lens; the laser beam passing the collimator enters into a light incident end of a Lambda/4 wave plate through a polarizer; the laser beam passing the Lambda/4 wave plate enters into a light incident end of a Kerr effect box, the laser beam transmitted through the Kerr effect box enters into a light receiving end of a CCD image sensor through a polarization analyzer and a filter; and the CCD image sensor is connected with a upper control computer. The device is suitable for measuring field distribution of liquid medium with small constant.
TL;DR: Theoretical analysis and real experiments show that the optical system can be used for a radially symmetric Hilbert transform that permits two-dimensional edge enhancement as the spiral phase plate in image processing.
Abstract: We analyzed the point spread function (PSF) of the typical 4f optical image processing system by use of a spatially variable half-wave plate as the spatial filter and found that the PSF is an elementary vector beam. Theoretical analysis and real experiments show that the optical system can be used for a radially symmetric Hilbert transform that permits two-dimensional edge enhancement as the spiral phase plate. This kind of radial Hilbert transform is useful for image processing because it can enhance the edges of an input image selectively by exerting a polarization analyzer before the output plane. The optical system also can be used for generation of vector beams with arbitrary array and shape in real time conveniently.
Patent•
11 Sep 2013
TL;DR: In this paper, a Mach-Zehnder interferometer was used to generate arbitrary vector beams based on a linear polarization laser source, a half-wave plate, two polarization splitting prisms, two totally reflecting mirrors, two discontinuous wave plates and an electro-optic phase modulator.
Abstract: The invention relates to a device for generating arbitrary vector beams based on a Mach-Zehnder interferometer. The device comprises a fundamental-mode linear polarization laser source, a half-wave plate, two polarization splitting prisms, two totally reflecting mirrors, two discontinuous wave plates and an electro-optic phase modulator, and the fundamental-mode linear polarization laser source generates a fundamental-mode Gaussian beam which is divided into two paths of orthogonal linearly-polarized light via the half-wave plate and the first polarization splitting prism. The vertically polarized light is converted into TEM01 vertically polarized light via the first 45-degree totally reflecting mirror and the first discontinuous wave plate; the horizontally polarized light is converted into TEM10 horizontally polarized light via the second discontinuous wave plate, and the TEM10 horizontally polarized light is reflected by the electro-optic phase modulator and the second 45-degree totally reflecting mirror and then is coaxially and coherently superposed with the TEM01 vertically polarized light at the position of the second polarization splitting prism to generate to vector polarized light. By the device, arbitrary phi0 and delta combined vector beams can be generated, and continuous and quick switching between different vector beams can be realized.
Patent•
11 Sep 2013
TL;DR: In this paper, a method for generating random column vector polarized beams by a single liquid crystal spatial light modulator is described, which is a low-cost, high-purity, multiple in variety of generated light beams, simple in structure, easy to operate and control and wide in applied range.
Abstract: Disclosed is a method for generating random column vector polarized beams by a single liquid crystal spatial light modulator A light beam generating system is composed of a laser device, a liquid crystal spatial light modulator, a battery of lenses, a lambada/2 wave plate, lambada/4 wave plates, a horizontal polarizing film, a triple prism, a reflector, a beam zooming device and the like Linearly polarized light in a random polarization direction is incident, light beam amplification is achieved after the battery of lenses, the lambada/2 wave plate can be used for adjusting the polarization direction of the linearly polarized light, horizontal line polarized beams are guaranteed to be obtained through the polarizing film transmitted in a horizontal direction, and beam intensity can also be adjusted by combining the lambada/2 wave plate and the polarizing film The horizontal line polarized beams pass through the liquid crystal spatial light modulator, then achieve space phase modulation, finally pass through a first lambada/4 wave plate, the liquid crystal spatial light modulator and a second lambada/4 wave plate in sequence by being reflected by the triple prism and the reflector, controls the polarization state of space light beams and generates the random column vector polarized beams When the two lambada/4 wave plates are removed, vortex beams can be generated The method for generating the random column vector polarized beams by the single liquid crystal spatial light modulator is low in cost, high in purity, multiple in variety of generated light beams, simple in structure, easy to operate and control and wide in applied range
Patent•
18 Dec 2013
TL;DR: In this article, a wave plate array based on pixels is proposed, which is composed of a plurality of wave plate units (11) which are vertically and horizontally arranged every two adjacent 2*2 wave plate unit units form a unit group.
Abstract: The invention discloses a wave plate array based on pixels The wave plate array is composed of a plurality of wave plate units (11) which are vertically and horizontally arranged Every two adjacent 2*2 wave plate units form a unit group (12) The thicknesses of the four wave plate units (11) in each unit group (12) are different, so that when light passes through different wave plates, the phase delay amounts of components, relative to components in the fast-axis direction, of a light vector in the slow-axis direction are not equal, and the phase delay amounts are 0, pi/2, pi and 3pi/2 respectively The wave plate array (1), a polarizing film (2) and an image sensor (3) can be sequentially overlaid to form an optical element The invention further discloses a plurality of preparation methods for preparing the wave plate array, and a method with the wave plate array The light intensity of object light, the phase distribution and four stoke parameters of light can be obtained only by collecting one frame image
TL;DR: Better, more accurate calibration of standard step height has been achieved by the developed interferometer, which also can measure solder bumps that traditional Mirau interferometers usually cannot measure.
Abstract: This work proposes an orthogonal polarization Mirau interferometry using a reflective-type waveplate to generate different polarization orientations for broadband white light interferometry. The reflective-type half-waveplate is employed as the reference arm of the Mirau interferometer to convert polarization and it generates a reference light with an orientation orthogonal to the object light. An advantage of the proposed interferometer is its ability to control the ratio of light intensity between the object and reference arms to maximize the interferometric fringe contrast. Better, more accurate calibration of standard step height has been achieved by the developed interferometer, which also can measure solder bumps that traditional Mirau interferometers usually cannot measure.
TL;DR: In this paper, a pair of polarizer and quarter waveplate is used to illuminate the transmissive twisted nematic liquid crystal spatial light modulator (TN-LCSLM) with elliptically polarized optical wave front and transmitted optical wavefront is analyzed with a rotating analyzer.
Abstract: The study of phase modulation from the transmissive twisted nematic liquid crystal spatial light modulator (TN-LCSLM) with different incident states of polarization on its active area using Digital Holography method is presented. A pair of polarizer and quarter waveplate is used to illuminate the TN-LCSLM with elliptically polarized optical wavefront and transmitted optical wavefront is analyzed with a rotating analyzer. A single digital hologram is recorded from a complex optical wavefront passing through active display area of the TN-LCSLM at particular setting of different optical elements and quantitative phase is evaluated. We demonstrated that elliptically polarized light with certain ellipticity produces maximum phase modulation through the TN-LCSLM and the results are in good agreement with the eigenvectors suggested by Mueller matrix polarimetric characterization. This experimental setup can also be used as Grey-field Polariscope (GFP) in order to characterize important physical parameters such as the orientation of LC director molecules at input face and phase retardation with respect to addressed gray scale value on the TN-LCSLM active area. The TN-LCSLM is illuminated with circularly polarized light and change in this incident polarization after passing through the TN-LCSLM is recorded by four phase shifted digital holograms at four different analyzer orientations to measure these physical parameters.
Patent•
27 Feb 2013
TL;DR: In this paper, the authors proposed a simultaneous polarization phase-shifting interferometer for field inspection of optical systems and optical inspection in complicated and severe environments, and continuous dynamic measurement can be achieved.
Abstract: The invention relates to a simultaneous polarization phase-shifting interferometer The interferometer uses a HeNe laser as a linear polarization coherent light source and comprises reference light and measurement light carrying phase information of a standard lens and a lens to be measured The reference light and the measurement light are reflected and transmitted by a polarization splitting prism respectively to be combined into one light beam in a same light path respectively, and a 1/4 wave plate and a beam splitter prism are arranged successively on the light path respectively; the light beam can be split into two portions with equal amplitudes by a depolarization splitting prism, and polarization splitting prisms are arranged on two split light paths; and image acquisition devices are arranged on the light paths after the light beams pass through the polarization splitting prisms respectively According to the simultaneous polarization phase-shifting interferometer, the wave plate and polarization prism structures are used, and polarized light interference is used, so that four interference images with a phase difference of pi/2 successively can be obtained at a same moment, effects of airflows and ambient vibration on measurement can be eliminated, the interferometer can be applied to field inspection of optical systems and optical inspection in complicated and severe environments, and continuous dynamic measurement can be achieved
Patent•
06 Feb 2013
TL;DR: In this paper, a light splitting synchronous phase shifting interference microscopy device and a detection method belonging to the field of optical interference detection was presented, where a light beam emitted from a light source is divided into an object light beam and a reference light beam, of which the polarization directions are mutually vertical.
Abstract: The invention discloses a light-splitting synchronous phase shifting interference microscopy device and a detection method, belonging to the field of the optical interference detection. The invention aims to solve the problems of difficulty and complexity in operation and low measurement precision of the traditional optical phase shifting interference detection method. The scheme is that a light beam emitted from a light source is divided into an object light beam and a reference light beam, of which the polarization directions are mutually vertical, after passing through a polarizing film and a first polarization light splitting prism; after gathered by a second polarization light splitting prism, the object light beam and the reference light beam successively pass through a lambda/4 wave plate, a rectangular window, a first Fourier lens, a one-dimensional period grating, a second Fourier lens, a depolarization light splitting prism and a four-quadrant polarizing film group; a polarization light beam emitted from the four-quadrant polarizing film group generates an interference pattern on the plane of an image sensor; the collected interference pattern is processed by a computer; and the phase distribution of an object to be detected is obtained.
Patent•
31 Jul 2013
TL;DR: In this paper, an optical waveguide voltage sensor based on double light path compensation was proposed. But the optical waveguide voltage sensor is not suitable for the use of optical fibers, since the inherent phase difference of the straight waveguide is pi 2 or odd times of pi 2, so that 1 4 lambda wave plate is omitted.
Abstract: The invention discloses an optical waveguide voltage sensor based on double light path compensation and belongs to the field of a photoelectric technology. The optical waveguide voltage sensor comprises a light source, a polarizer, a straight waveguide and a polarization beam splitter which are connected sequentially by all polarization maintaining optical fibers, and further comprises a photoelectric detector and a signal processing unit. The inherent phase difference of the straight waveguide is pi/2 or odd times of pi/2, so that 1/4lambda wave plate is omitted. A sensing part of the optical waveguide voltage sensor is made of the straight waveguide, and the straight waveguide can be directly coupled into the optical fibers, so that the defects of a blocky crystal type optical voltage sensor are overcome, and the optical waveguide voltage sensor has the advantages of small size, light weight, simple structure, convenience for manufacturing and the like. All the devices are connected through the optical fibers, so that inconvenience in adjusting complex discrete optical devices is avoided, the light path is simple and easy to realize, the light path space is greatly reduced, transportation and mounting are facilitated, and large-scale production is easy.