Abstract:
Dispositivo óptico integrado (1) en miniatura compuesto por un Interferometro Mach- Zehnder (2) que comprende un acoplador óptico multimodo (6), una primera guía de onda (10) de longitud Ι_+ΔΙ_ y una segunda guía de onda (11) de longitud L, estando la primera guía de onda (10) y la segunda guía de onda (11) acopladas a la salida del acoplador óptico multimodo (6), y donde el Interferometro Mach-Zehnder (2) está conectado a su salida a un bloque seleccionado entre: un "Arrayed Waveguide Grating", AWG (3) con una separación determinada entre las guías de onda (10, 11) y un "Interleave-Chirped AWG", IC-AWG (4, 5) con una separación determinada entre las guías de ondas (10, 11). Lo que se consigue con este dispositivo (1 ) es que en cada salida se tenga una pequeña banda del espectro, es decir se tiene un dispositivo (1) de múltiples canales.
Abstract:
A system is described that combines spectropolarimetry with scatterometry. The system uses an annular mirror and liquid crystal devices to control the angle of the incident light cone, the polarization and wavelength, an imaging setup and one or more video cameras so that spectroseopic- polarimetric-scatterometric images can be grabbed rapidly. The system is also designed to incorporate additional imaging modes such as interference, phase contrast, fluorescence and Raman spectropolarimetric imaging.
Abstract:
An interferometer comprising a planar substrate is provided. The interferometer has a splitter formed on the planar substrate to split a received optical signal, a sample arm formed on the planar substrate to receive a first portion of the split optical signal and direct the first portion toward a sample, a reference arm formed on the planar substrate to receive a second portion of the split optical signal, and a detector element to receive an interferogram generated by interfering the second portion of the split optical signal with a received sample signal generated by the first portion of the split signal interacting with the sample.
Abstract:
Heterodyne interferometry is combined with spectrally-controlled interferometry (SCI) to achieve the advantages of both. Phase shifts produced by SCI produce phase-shifted correlograms suitable for heterodyne interferometric analysis, thereby enabling interferometric measurements with conventional common-path apparatus free of coherence noise and scanning-related errors, and with the precision of conventional heterodyne interferometry. A spectrum-modulating light source (10) suitable for the invention is obtained by combining a rotating spiral grating (30) with a multi-slit grating (12) placed in the front focal plane of a collimating lens (14) that propagates the light toward a blazed diffraction grating (18). Another exemplary spectrum-modulating light source (50) is obtained by combining a slit spectrometer with an acousto-optic modulator (40).
Abstract:
Verfahren und Vorrichtung zur optischen Überprüfung einer Probe mittels spektraler Interferometrie, wobei ein von einer Strahlungsquelle (1) abgegebener Strahl (2'') auf die Probe (5) sowie ein Referenzstrahl (2') auf eine Referenzprobe (4) gerichtet werden und die spektrale Interferenz der beiden Strahlen nach Reflexion an den Proben oder Passieren der Proben mittels eines Spektrographen (6) aufgenommen wird; das so erhaltene Interferogramm I (ω) wird numerisch nach der Kreisfrequenz ω abgeleitet, wonach für die so erhaltene Funktion I `(ω) die Nullstellen ω i numerisch als Lösungen der Gleichung I `(ω) = 0 berechnet werden und danach aus den Nullstellen ω i die frequenzabhängige Gruppenverzögerung τ (ω) entsprechend der Gleichung τ (ω n ) = π/ (ω i+1 -ω i ), mit i = 1,2... und ω n = (ω i+1 + ω i ) /2, berechnet wird.
Abstract:
A spatial heterodyne spectrometer has a two beam dispersive interferometer (25) which includes a diffraction grating (45) as a beam splitter/combiner. An incoming beam is collimated and passed to the grating (45) in the interferometer (25) where it is split into two beams (47, 50) which are recombined such that the angle between the wavefronts in the recombined beam at a particular wavelength is directly related to the deviation of that wavelength from a null wavelength at which the wavefronts are parallel. The recombined output beam is focused and imaged to produce Fizeau fringes across the output aperture (31), with these fringes being recorded on an imaging detector (34). The spatially varying intensity output of the imaging detector (34) is Fourier transformed to yield an output indicative of the spectral frequency content of the image which is related to the wavelength content of the incoming beam from the source.