Abstract:
A method for the non-destructive inspection of a part made from an organic-matrix composite material (CMO) includes the steps of: a) carrying out a surface inspection of the part by Fourier transform infrared spectroscopy (FTIS), b) if step a) reveals a defect, carrying out in-depth inspections of the organic-matrix composite material according to two complementary ultrasound techniques.
Abstract:
Described are a method and apparatus for high-speed phase shifting of an optical beam. A transparent plate having regions of different optical thickness is illuminated by an optical beam along a path of incidence that extends through the regions. The transparent plate can be moved or the optical beam can be steered to generate the path of incidence. The optical beam exiting the transparent plate has an instantaneous phase value according to the region in which the optical beam is incident. Advantageously, the phase values are repeatable and stable regardless of the location of incidence of the optical beam within the respective regions, and phase changes at high modulation rates are possible. The method and apparatus can be used to modulate a phase difference of a pair of coherent optical beams such as in an interferometric fringe projection system.
Abstract:
An imaging spectrometer includes a Fabry-Perot interferometer and an image sensor having color-sensitive pixels. The interferometer has a first transmission peak and a second transmission peak (PEAK2). A method calibrating the spectrometer includes providing first calibration light, which has a narrow spectral peak, obtaining first detector signal values from the image sensor by coupling the first calibration light into the spectrometer when the reference spectral peak is near a first spectral position, obtaining second detector signal values from the image sensor by coupling the first calibration light into the spectrometer when the reference spectral peak is near a second spectral position, providing second calibration light, which has a broad bandwidth, and obtaining third detector signal values from the image sensor by coupling the second calibration light into the spectrometer.
Abstract:
An optical path of measurement light emitted from a measurement light source is overlaid by a beam combiner on an optical path of reference light emitted from a reference light source. The measurement light emitted from the measurement light source includes light in the sensitivity wavelength range (S1) of a measurement light detector and light in the sensitivity wavelength range (S2) of a reference light detector. An interferometer includes a wavelength separation filter that cuts light in at least a part of the sensitivity wavelength range (S2) of the reference light detector, of light included in the wavelength range of the measurement light.
Abstract:
Method of characterizing a light beam (FL) comprising the steps consisting in: a) disposing the input ends (EE1-EE11) of N>3 optical fibres (F01-F011) on the path of said light beam, in such a way that a respective portion of said beam is coupled and propagates in each optical fibre and is emitted from its output end (ES1-ES11) so as to form a respective secondary beam; b) introducing an angular spectral dispersion into said secondary beams by means of at least one dispersive element (RD); c) propagating the dispersed secondary beams in such a way that they overlap to form an interferogram; d) acquiring an image of said interferogram; and e) extracting from said image of said interferogram an item of information relating to the spatial variation of the phase of said light beam at a plurality of wavelengths. Device for the implementation of such a method.
Abstract:
A microelectromechanical system (MEMS) (10), and a microelectromechanical (MEM) optical interferometer (18), for hyper-spectral imaging and analysis. System (10) includes matrix configured collimating micro lens (16), for receiving and collimating electromagnetic radiation (60) emitted by objects (12) in a scene or sample (14); microelectromechanical optical interferometer (18), for forming divided collimated object emission beam (72) having an optical path difference, and for generating an interference image exiting optical interferometer (18); matrix configured focusing micro lens (20); micro detector (22), for detecting and recording generated interference images; and micro central programming and signal processing unit (24). Applicable for on-line (e.g., real time or near-real time) or off-line hyper-spectral imaging and analyzing, on a miniaturized or ‘micro’ (sub-centimeter [1 cm (10 mm) or less], or sub-millimeter) scale, essentially any types or kinds of biological, physical, or/and chemical, (i.e., biophysicochemical) objects.
Abstract:
A system for measuring the absorption spectrum of a sample is provided that includes a broadband light source that produces broadband light defined within a range of an absorptance spectrum. An interferometer modulates the intensity of the broadband light source for a range of modulation frequencies. A bi-layer cantilever probe arm is thermally connected to a sample arm having at most two layers of materials. The broadband light modulated by the interferometer is directed towards the sample and absorbed by the sample and converted into heat, which causes a temperature rise and bending of the bi-layer cantilever probe arm. A detector mechanism measures and records the deflection of the probe arm so as to obtain the absorptance spectrum of the sample.
Abstract:
A Fourier Transform Infrared (FTIR) Spectrometer integrated in a CMOS technology on a Silicon-on-Insulator (SOI) wafer is disclosed. The present invention is fully integrated into a compact, miniaturized, low cost, CMOS fabrication compatible chip. The present invention may be operated in various infrared regions ranging from 1.1 μm to 15 μm or it can cover the full spectrum from 1.1 μm to 15 μm all at once.The CMOS-FTIR spectrometer disclosed herein has high spectral resolution, no movable parts, no lenses, is compact, not prone to damage in harsh external conditions and can be fabricated with a standard CMOS technology, allowing the mass production of FTIR spectrometers. The fully integrated CMOS-FTIR spectrometer is suitable for battery operation; any and all functionality can be integrated on a chip with standard CMOS technology. The disclosed invention for the FTIR spectrometer may also be adapted for a CMOS-Raman spectrometer.
Abstract:
A optical module includes, a wavelength variable interference filter which include reflection films opposite to each other and an electrostatic actuator portion including a first electrostatic actuator and a second electrostatic actuator and changing a gap between the reflection films, and a voltage control portion which controls voltage which is applied to the electrostatic actuator portion, the voltage control portion includes, a bias driving portion which applies bias voltage to the first electrostatic actuator, a gap detector, and a feedback control portion which applies feedback voltage corresponding to a detected gap amount to the second electrostatic actuator.