Monolithic Fourier-transform imaging spectrometer

Abstract

The design of a monolithic imaging Fourier-transform spectrometer based on a Sagnac interferometer is discussed.

Stationary spatially modulated fourier transform spectro-radiometer

“…Improvements can be made in the spectral resolution of the sensor by increasing the number of elements in the detector array and also by increasing the spacing between the virtual sources. This system can be made extremely stable, compact and immune to damage and misalignment by combining the beam splitter and the two path folding mirrors into a monolithic, solid block interferometer (Rafert et al, 1995). This type system, being an interferometer, has high signal to noise ratio and has no moving parts makes it most suitable candidate for making field measurements and is amenable for conversion into an Hyper spectral push-broom imaging sensor (Rafert et al, , 1995 for airborne and spaceborne measurements, by using 2-D detector array in the place of linear CCD array and a vertical slit aperture.…”

“…A cylindrical lens is placed between the Fourier lens and the detector such that it has zero power in the direction parallel to the line joining the virtual sources. It is used to image the source aperture in the perpendicular direction and allows the spatially resolved observation of target along the slit direction, when used with two-dimensional array detector (Rafert et al, 1995). The detector array samples the interferogram and generates the electrical signal.…”

“…They have recorded the pattern on a photographic plate and reconstructed the spectrum in a coherent optical Fourier processor. With the availability of self-scanning photo-diode array, a number of systems were developed (Takayuki et al, 1984;Rafert et al, , 1995Padgett et al, 1994) in which the interferogram is measured with detector array and the spectrum is obtained bY digital Fourier transformation of the detector signal.…”

Polarization detection with polarization interference imaging spectrometer

“…At present, only the interferential characteristics of light are taken good used to detect the object in the polarization interference imaging spectrometer (PIIS) system [5], but the polarized characteristics are usually ignored which means much valuable information may be lost. With the recent development of polarization interference imaging spectroscopy [6][7][8][9], the subject of polarization detection using these spectrometers has become more important which means more information could be got by one PIIS. Although a lot of different technological approaches of imaging polarimeters have been studied [10][11][12], the Fourier spectroscopy method is well known to possess the multiplex advantage [5].…”

Demonstration of a Corner-cube-interferometer LWIR Hyperspectral Imager

“…The scene moves relative to the static interferogram and successive interferograms represent sequential pixels of a given row. Given the advantage of a mechanically robust optical train, the Sagnac interferometer is an often-used configuration, with a number of successfully fielded instruments [3][4][5][6].…”