Abstract:
The invention relates to a spectrograph (11) comprising a waveguide (10) provided with accesses (10; 10b, 12), a means for injecting two guided contra-propagative waves by each accesses in such a way that a spatial interference is formed in the waveguide, means (19, 20, 14, 16) for detecting the energy of the evanescent wave of the guided field produced by the interference of said contra-propagative waves.
Abstract:
The field of the invention is that of spectroscopic analysis devices allowing the spectral analysis of radiation. The device according to the invention is of the interference type, it comprises at least a first reflecting layer onto which is deposited a multilayer of alternately transparent and photo-absorbing thin films, each photo-absorbing layer being connected to electronic detection means supplying a primary electronic signal and the device also comprising means for analyzing the primary signals and configured in such a manner as to determine the spectral distribution of the original radiation.
Abstract:
The present invention provides an economically feasible robust spatial heterodyne spectroscopy (SHS) interferometer. A first type prior art monolithic SHS interferometer is exceedingly expensive, whereas a second type of prior art SHS interferometer is extremely large and has many components, which need to be tuned. The present invention is much less expensive than the first type of prior art SHS interferometer and is much smaller that the second type of prior art SHS interferometer.
Abstract:
Novel spectrometer arrangements are described. They may employ a resin-based preconcentration system to sample chemical vapors. A field-widened interferometer modulates radiant energy. The signal generated by the interaction of the radiant energy with the sample is detected and processed by a computer. A variety of enhancements to the basic design are described, providing a family of related spectrometer designs. These spectrometers have applications in spectrometry, spectral imaging and metrology.
Abstract:
Real time high speed high resolution hyper-spectral imaging. (a) electromagnetic radiation collimating element (16), collimating electromagnetic radiation (44) emitted by objects (12) in a scene or a sample (14); (b) optical interferometer (18), receiving and dividing collimated object emission beam, generating interference images, and determining and piezoelectrically changing magnitude of optical path difference of divided collimated object emission beam; optical interferometer (18) includes: beam splitter (20′), fixed mirror (22), movable mirror (24), piezoelectric motor (26), displacing movable mirror (24) along axis (60), distance change feedback sensor (28), sensing and measuring change in distance of movable mirror (24) along axis (60), piezoelectric motor controller (30), actuating and controlling piezoelectric motor (26); and thermo-mechanically stable optical interferometer mount (32A); (c) camera optics (34), focusing interference images of each optical path difference; (d) detector (36), recording interference images; (e) central programming and signal processing unit (38), and (f) display (40).
Abstract:
The invention relates to an interferometer, comprising at least a beam splitter (10), an end mirror (11) for returning beams (S2, S3), and a set of mirrors (12, 13, 14, 15) for reflecting the beams (S2, S3) between the beam splitter (10) and the end mirror (11), at least some of said mirrors (12, 13, 14, 15) being mounted on a rigid structure (17) which is arranged to be rotatable around an axis (A). Said set of mirrors comprises at least one pair of planar mirrors, constituted by two plane mirrors (12, 13), and two angular mirrors (14, 15), constituted by plane mirrors and arranged to deflect a course of the beam (S2, S3) hitting the angular mirror (14, 15) and to direct the beams (S2, S3), guided from the beam splitter (10) by way of at least one pair of plane mirrors (12, 13) to the angular mirrors (14, 15), to the end mirror (11) and back to the beam splitter (10).
Abstract:
In accordance with the principles of the invention, a lamellar grating interferometer breaks the radiation down into its wavelength components. The two sets of teeth of the grating are moved relative to each other. The spectral output of the interferometer is focused on an array of detectors and data is stored for a large number of positions of the grating teeth. The collected data is then Fourier transformed to recover the spectrum of the radiation.
Abstract:
The Miniature Fourier Transform Spectrophotometer provides the capability, in a miniaturized device, of determining the light absorption/transmission spectra of a collected sample of gas or liquid though Fourier Transform spectroscopy techniques. The device takes an optical input from an optical fiber, manipulates that light through miniature optical components, and launches it into a miniaturized Michelson interferometer with a scanning mirror that acquires the interferogram of the optical input. The interferogram can be processed to retrieve the spectrum of the input light. A novel multi-stepped micro-mirror operates as the optical path length modulator in the miniaturized interferometer. A unique monolithic beamsplitter/mirror combination provides for accurate alignment of the components and greatly simplifies product integration. The device is designed to cover various optical spectra of interest. During operation, the precision and accuracy of the microfabricated components in the device allow operation and resolution even at extremely low wavelengths. In addition, the miniaturized nature of the device allows it to be used in new and extremely space-constrained applications.
Abstract:
A sensor having an input to an interferometer. The input may receive emissions from a detected fluid. The output of the interferometer may be focused on an array of light detectors. Electrical signals from the detectors may go to a processor. The output of the processor may include a spectrum of the detected fluid. Also, the identity of the fluid may be determined.
Abstract:
A spectroscopic method and system for the spectral analysis of an optical signal directed to a wavelength dispersive component having two interleaved dispersive devices. For a single wavelength, the optical signal exiting the interleaved dispersive devices includes two wavefronts generally disposed at an angle to one another and producing an interference pattern. The interference pattern is detected and subsequently analyzed via a Fourier transform to produce the optical spectrum of the input beam. The method and system are applicable in a planar waveguide environment, in reflection and transmission geometries.