- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Pixelated-polarization-camera-based polarimetry system for wide real-time optical rotation measurement
摘要： Chirality is an essential consideration in the field of life sciences and pharmaceutical industry because most biomolecules and pharmaceuticals are chiral, and optical rotation measurement is a simple and efficient means for identification, purity test and content detection of chiral materials. However, there are some drawbacks in existing methods, such as small measurement range, non-real-time performance, low measurement accuracy and resolution. This paper presents a novel system to implement optical rotation measurement, and pixelated polarization cameras and Stokes parameters are employed in the system. The polarization information of linearly polarized incident light can be recorded and extracted by a pixelated polarization camera and Stokes parameters respectively. Experiments demonstrate that the proposed system has the necessary advantages for optical rotation measurement, such as real time, wide range ( ?90 ° ～ +90 °), high accuracy ( ±4 ×10?6 °) and high resolution ( 6 ×10?11 °). Thus, this measurement system has great practical prospects in the hospital clinical diagnosis, chemical research, sugar production and pharmaceutical industry.
关键词： pixelated micropolarizer array,optical rotation,chiral drug,polarimetry,Stokes parameters
更新于2025-11-25 10:30:42
-
Intensity modulation-based spectral polarization measurement method of coded aperture
摘要： This paper presents a spectral polarization measurement method for single-frame imaging. The method is based on intensity-modulated, coded aperture measurement, comprising a spectral polarization intensity modulation and a compressive sensing spectral imaging system. The incident light is modulated by two multistage phase retarders and a polarizer, and the spectrum's Stokes parameters are shifted to different frequency channels. The spectrum of the modulated light is obtained by a spectral imaging system composed of a coded aperture and a dispersive prism. The modulated spectral information is reconstructed using the TwIST algorithm, and the Stokes elements can be demodulated from it. Taking a pixel as an example, numerical simulations of the modulation of incident light intensity modulation, spectral reconstruction, and demodulation of Stokes parameters show that the method can acquire spectral polarization information of sparse images. This process needs only one measurement of the object and is therefore capable of high-speed acquisition.
关键词： Intensity modulation,Stokes parameters,Coded aperture
更新于2025-09-23 15:23:52
-
Modified Sagnac imaging spectropolarimeter for full linear Stokes parameters
摘要： A modified Sagnac imaging spectropolarimeter is conceptually described. It consists of a spectral-polarimetric modulator, a modified Sagnac interferometer with large optical path difference, and a CCD camera. This design modulates the Stokes components of the input light into different wave numbers and obtains the modulated interferogram in snapshot mode, and the spectra of the Stokes components can be separated and demodulated from the interferogram. The performance of the system is demonstrated through a numerical simulation, and a novel method is proposed to detect the polarization parameters including the degree of polarization and polarization direction for eliminating the aliasing effects between linear Stokes parameters. Compared with the existing imaging spectrometers, the modified Sagnac imaging spectropolarimeter can acquire one-dimensional spatial information and its full linear spectropolarimetric information in one exposure, and some other spatial information can be obtained by push-broom mode.
关键词： imaging spectropolarimeter,snapshot mode,Stokes parameters,polarization,Sagnac interferometer
更新于2025-09-23 15:23:52
-
Arbitrary Polarization Conversion with a Photonic Crystal Slab
摘要： It is shown that a simple photonic crystal slab structure provides a powerful mechanism for the control of the polarization properties of light. For a lossless system, for a given incident light with any fixed polarization, one can generate arbitrary polarization in the reflected light, as one varies the direction of the incident light. In the lossy system, the capability for arbitrary polarization generation is still preserved for s- or p-polarized incident light. This capability for arbitrary polarization generation closely relates to the nontrivial topological properties of the reflection matrix of the structure and exists over a wide range of frequencies.
关键词： photonic crystals,polarization conversion,Poincaré sphere,Stokes parameters
更新于2025-09-23 15:22:29
-
[IEEE 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Odessa, Ukraine (2018.9.4-2018.9.7)] 2018 9th International Conference on Ultrawideband and Ultrashort Impulse Signals (UWBUSIS) - Polarization Properties of the Fabry-Perot Resonator with Coaxial-Sector Apertures in Mirrors
摘要： Numerical electrodynamic properties of the Fabry-Perot resonator with coaxial-sector apertures and waveguide loads have been performed. The possibility of obtaining the circular polarization of the electric field in the volume of the resonator is revealed. It is shown that the polarization of the electric field in the resonator volume can be controlled by changing the distance between the mirrors or the length of the shorted waveguides of one of the mirrors.
关键词： the Stokes parameters,Fabry-Perot resonator,coaxial-sector waveguide
更新于2025-09-23 15:21:21
-
Wave Polarization Analyzed by Singular Value Decomposition of the Spectral Matrix in the Presence of Noise
摘要： Analysis of wave polarization provides wave propagation parameters and enables an identification of modes in space plasmas. It is based on measurements of several components of fluctuating electromagnetic fields. This technique has become a conventional part of modern instrumentation onboard scientific spacecraft. A definition of the degree of polarization can be reduced to a very basic form, i.e., the ratio of a signal’s polarized power to its total power. However, this simple definition can have several different realizations which depend mainly on the underlying assumptions about separating the polarized (coherent) part from the unpolarized part (noise). After reviewing polarization of a plane wave in two and three dimensions, we examine the singular value decomposition technique for a complex spectral matrix as well as for a real spectral matrix. The meaning of singular values is explained, and we show to what extent the singular values are able to contribute to a separation between polarized signal and noise. Finally, our theoretical findings are verified with synthetic data as well as with whistler-mode chorus wave observations from the THEMIS spacecraft.
关键词： Singular value decomposition,Wave normal vector,Hermitian spectral matrix,Spectral averaging,Stokes parameters,Degree of polarization,Planarity,Singular values,Ellipticity,Plane wave,Eigenvalues,Polarization analysis
更新于2025-09-19 17:15:36
-
Ellipsometry - Principles and Techniques for Materials Characterization || Achromatic Ellipsometry: Theory and Applications
摘要： In the present chapter, the theory and some applications of Achromatic Ellipsometry, including transmittance, absorbance, and emission, are presented. The new methodology introduced here comprises the calculation of Stokes parameters using Fourier series analysis. Light polarization was determined by calculating the polarization degree, anisotropy, asymmetry parameters, and rotational and ellipsometry angles. The nematic liquid crystal E7? doped with 4,7-bis{2-[4-(4-decylpiperazin-1-yl)phenyl]ethynyl}-[2,1,3]-benzothiadiazole (5A) within twisted and parallel structures, was used to illustrate the applications for this technique, that has been shown to be an innovative and versatile tool to correlate the photophysics with materials structure.
关键词： ellipsometry,Stokes parameters,optical spectroscopy
更新于2025-09-09 09:28:46
-
Imaging and visualization of the polarization state of the probing beam in polarization-sensitive optical coherence tomography
摘要： We propose a simple and ef?cient method of color-encoded Stokes parameters to visualize the polarization states for polarization-sensitive optical coherence tomography (PS-OCT) of biological tissue. In this method, polarization states of the probing light are detected and described in the Stokes domain. Three primary colors of red, green, and blue are used to code Stokes parameters of Q, U, and V, respectively, which can be used to represent and visualize each unique polarization state. A strategy that uses the polarization state as the PS-OCT imaging parameter is ?rst introduced to obtain high contrast images of the birefringent samples. Then, color-based automatic segmentation of birefringent components from 3D scanned tissue volume is proposed to isolate the network of the 3D nerve bundles in a mouse brain without cutting the brain into slices. Experimental validation and demonstrations are given by imaging ex vivo mouse tail and brain tissues to show the usefulness of proposed polarization state imaging and segmentation methods.
关键词： automatic segmentation,Stokes parameters,birefringent tissue,polarization-sensitive optical coherence tomography,polarization state imaging
更新于2025-09-04 15:30:14
-
Input-to-Output Instantaneous Polarization Characterization
摘要： This paper proposes a method to represent and predict received signal instantaneous polarization states as a function of arbitrary transmit polarization states for time-dispersive channels. The model incorporates frequency-dependent characterizations to represent the polarization dispersion behavior of a received signal across its bandwidth in a multipath channel. The representation takes advantage of signal dispersion features typical of depolarized signals, and employs subbanded characterizations to achieve polarization representations exhibiting high degrees of polarization in each subband. Experiments are conducted that demonstrate the utility of the modeling approach to predict polarization dispersion responses for arbitrary transmit polarizations based on measurements from two orthogonal transmit polarizations.
关键词： radiowave propagation,Stokes parameters,polarization estimation,dispersion
更新于2025-09-04 15:30:14