Abstract:
A spectroscopic system for the analysis of small and very small quantities of substances makes use for the purposes of energy transfer of cone-shaped aperture changers (14, 15) which are arranged in the object zone (8) between the light source (L) and the sample (9) and, during absorption measurements, also between the sample (9) and the inlet slot (3) of a spectrometer (1). If the form used is a double cone, the aperture changers (14, 15) facilitate an oblique coupling in a capillary tube accepting the sample (9) which acts as a step-waveguide for the coupled radiation.
Abstract:
A method of, and system for, applying light beam producing systems such as ellipsometers, polarimeters, polarized light reflectance and functionally similar systems, such that a beam of light produced thereby is caused to be incident upon a process element at an angle in excess of an associated Brewster angle while enabling the production of a signal sufficiently sensitive to changes in process element parameters, for use in "real-time" process element process monitoring and control, is disclosed. In addition a process element processing system and electron beam producing system and light beam producing system combination system is taught, wherein the electron beam producing and light beam producing systems are mounted to the process element processing system, (typically a (MBE) system), by input and output interface systems present at a location appropriate for conventional Reflection High Energy Electron Diffraction (RHEED) systems.
Abstract:
In FT-DIRLD (Dynamic Infra Red Linear Dichroism) apparatus partly represented in FIG. 1, units 100-105, responding to interferometer output IB (indicated elsewhere), cause unit 106 to yield an interferogram combining static and dynamic dichroism interferograms. Reference signals respectively in phase and quadrature with cyclic sample strain are derived from rheometer 102. At each OPD point of predetermined uninterrupted scans, controller 108 routes simultaneously a data point of the combined interferogram and the reference signals to respective channels of multiplexer 107. A microprocessor (shown elsewhere) subsequently performs a best-fit-to-an ellipse sorting of the data and for each OPD derives: A) the value of the interferogram unaffected by sample modulation; B) the corresponding in phase term; and C) the corresponding in quadrature term; furthermore, from the A, B,C data-point series it generates the interferogram of each series and transforms it into a spectrum. DIRLD analysis is achieved asynchronously and in continuous fast scanning.
Abstract:
The polarization interferometer comprises a source of light (1), a collimator (2), a first polarizing means (3), a double-refractive means (4,5,6) and a second polarizing means (7) which polarizes the light emerging from the double-refractive means (4,5,6) and directs it to a photon detector (8). The double-refractive means (4,5,6) consists of two optical wedges (5,6) displaceable along those lateral surfaces which face each other, said wedges complementing each other to a right parallelepiped, and of a double-refractive, plane-parallel plate (4) serving as a compensator. The optical axis of the compensator (4) is twisted in a plane perpendicular to the light beam by a finite angle relative to that of the two wedges (5,6), the optical axes of the two wedges (5,6) coinciding with each other. The optical axes of the two polarizing means (3,7) are arranged perpendicularly or parallely to each other and are aligned non-parallely to the axes of the two wedges (5,6) of the double-refractive means (4,5,6).
Abstract:
An acousto-optic spectrometer/polarimeter for analyzing an incident broad-band beam including an acousto-optic tunable filter (AOTF) for separating the incident broad-band beam into a diffracted extraordinary narrow-band beam, a diffracted ordinary narrow-band beam, and at least one undiffracted broad-band beam; first, second and third detectors respectively positioned to respectfully receive at least a portion of the diffracted extraordinary narrow-band beam, the diffracted ordinary narrow broad-band beam and the at least one undiffracted broad-band beam, and to respectively provide first, second and third signals based thereon; a subtracter for providing a polarimeter output by taking the difference between the first and the second signals; and an adder for providing a spectrometer output by adding the first and the second signals. The acousto-optic spectrometer/polarimeter according to the present invention allows broad-band imaging, spectroscopy and polarimetry to be performed simultaneously and through the same optical aperture.
Abstract:
A method and device for detecting dichroic and/or birefringent narrow spectral features in a sample is described. The method includes the steps of providing a beam of light having an optical frequency bandwidth which is narrow compared to the width of the narrow spectral feature and having a center frequency .omega..sub.c which lies near the narrow spectral feature, polarization phase modulating a beam of light with a single RF frequency to provide a pure FM spectrum having upper and lower sidebands in which either the carrier and sidebands have been polarized with respect to one another, exposing the sample containing the narrow spectral feature to the polarized modulated light so that the FM sidebands probe the narrow spectral feature, polarization analyzing and then photodetecting the light emerging from the sample to detect a RF beat at the specific RF frequency used for the polarization phase modulation, and electronically monitoring the amplitude of the RF beat signal to indicate the strength of the narrow spectral feature. The device includes a polarization phase modulator and a polarization analyzer positioned on opposite sides of the sample. In a preferred embodiment the polarization phase modulator produces a frequency modulated optical spectrum with the sidebands polarized precisely orthogonal to the carrier.
Abstract:
Disclosed herein an apparatus and method for estimating a phase retarder and method of manufacturing the phase retarder using the same. The apparatus includes: a polarization element configured to output an incident light as a linear polarization and to make the linear polarization incident onto a phase retarder to be tested; a polarization image acquisition module equipped with a plurality of polarized pixels receiving an emitting light that is output from the phase retarder, on which the linear polarization is incident, and configured to obtain a polarization image based on the emitting light that is modulated in the polarized pixels; and a processor configured to evaluate quality of the phase retarder based on uniformity of a brightness value between polarized pixels of the polarization image. The polarized pixels modulate the emitting light based on a plurality of transmission angles and detects the modulated emitting light.
Abstract:
A polarization intelligent sensing system and a polarization intelligent sensing method are provided. The polarization intelligent sensing method includes performing the polarization imaging on the target scene to obtain the polarization image, performing the calculation on the polarization image to obtain the polarization information of the target scene, generating the image information to be restored of the target scene according to the polarization information of the target scene, and constructing the multi-dimensional target detection neural network based on the DETR, and obtaining the interpretation information of the target scene based on the image information to be restored of the target scene, the spectral information, or the intensity information through the neural networks. The system and the method are widely applied to environments of various carrying platforms, has strong environmental adaptability, and is capable of obtaining target scene information that cannot be sensed by a conventional optical sensor.
Abstract:
This relates to systems and methods for measuring a concentration and type of substance in a sample at a sampling interface. The systems can include a light source, optics, one or more modulators, a reference, a detector, and a controller. The systems and methods disclosed can be capable of accounting for drift originating from the light source, one or more optics, and the detector by sharing one or more components between different measurement light paths. Additionally, the systems can be capable of differentiating between different types of drift and eliminating erroneous measurements due to stray light with the placement of one or more modulators between the light source and the sample or reference. Furthermore, the systems can be capable of detecting the substance along various locations and depths within the sample by mapping a detector pixel and a microoptics to the location and depth in the sample.
Abstract:
A chiral molecule can be defined as a molecule that has a non-superimposable mirror image. These mirror images can be referred to as enantiomers. The enantiomers generally have the same set of bond lengths and bond angles in their three-dimensional geometry. Apparatus and techniques described herein can be used to perform analysis of chiral molecules using cavity-enhanced molecular rotational spectroscopy. A sample cell can define a resonant cavity, and a sample introduction port can provide pulse-jet injection of an analyte molecule and a chiral tag to allow analysis of a complex comprising the analyte and chiral tag.