Proceedings, XXth congress: Proceedings, XXth congress

Altan, M. Orhan

Bibliographic data

Multivolume work

Persistent identifier:: 1663674213

Title:: Proceedings, XXth congress

Sub title:: Istanbul, 12 - 23 July 2004

Year of publication:: 2004

Place of publication:: Istanbul

Publisher of the original:: [Verlag nicht ermittelbar]

Identifier (digital):: 1663674213

Language:: English

Additional Notes:: Erscheinungsdatum des Originals ist aus dem Copyrightjahr ermittelt.; Auch bezeichnet als XXth International Congress for Photogrammetry and Remote Sensing

Editor:: Altan, M. Orhan

Corporations:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing, Commission Primary Data Acquisition

Adapter:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing, Commission Primary Data Acquisition

Founder of work:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing, Commission Primary Data Acquisition

Other corporate:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing, Commission Primary Data Acquisition

Document type:: Multivolume work

Volume

Persistent identifier:: 166368779X

Title:: Proceedings, XXth congress

Scope:: IV, 226 Seiten

Year of publication:: 2004

Place of publication:: Istanbul

Publisher of the original:: [Verlag nicht ermittelbar]

Identifier (digital):: 166368779X

Illustration:: Illustrationen, Diagramme

Signature of the source:: ZS 312(35,B8)

Language:: English

Additional Notes:: Erscheinungsdatum des Originals ist aus dem Copyrightjahr ermittelt.

Usage licence:: Attribution 4.0 International (CC BY 4.0)

Editor:: Altan, M. Orhan

Corporations:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing

Adapter:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing

Founder of work:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing

Other corporate:: International Society for Photogrammetry and Remote Sensing, Congress, 20., 2004, Istanbul; International Society for Photogrammetry and Remote Sensing

Publisher of the digital copy:: Technische Informationsbibliothek Hannover

Place of publication of the digital copy:: Hannover

Year of publication of the original:: 2019

Document type:: Volume

Collection:: Earth sciences

Chapter

Title:: EARLY RESULTS FROM AN IMAGING INTERFEROMETER PROTOTYPE OPERATING IN THE SAGNAC CONFIGURATION Paolo Marcoionni

Document type:: Multivolume work

Structure type:: Chapter

spectral ationary nt does dulated ntensity . present esponse red He- halogen dure of esponse ints are maging 996). ng high nd the solution and the nttila et vides a (SNR). am it is icy. of ata-rate coming 'trieved ition, a in the Section 1 of the alibrate Section | and in Sagnac International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B-YF. Istanbul 2004 P Figure 1. Conceptual layout of the stationary interferometer arranged in the Sagnac (triangular or cyclic path) geometry The light from the object is first collimated by the objective L, and, by means of a beam-splitter BS and two folding mirrors M1 and M2, is focused onto a CCD plane by the lens P. Like the Michelson device, this Sagnac interferometer also uses a beam-splitter (as source-doubling technique) but inside of a common (triangular) path with a tilt introduced between the two interfering image wavefronts to form a fixed (stationary) pattern of interference fringes of “equal thickness”. The BS is the fundamental component, which provides phase- delay between the two coherent interfering rays so that the OPD changes linearly with varying the angle of the entering ray with respect to the instrument optical axis. Therefore, the device acquires the image of an object superimposed to a fixed pattern of across-track interference fringes. Then, introducing a relative motion between the sensor and the object, each scene pitch experiences the same interference pattern and an entire image- frame is recorded for each autocorrelation phase offset. The 3-D array of these frames has to be “realigned” in order to extract the complete autocorrelation function (interferogram) of each scene pixel, then this record is inverse cosine transformed to yield a wavenumber hyperspectral data cube. Differently from the FTHSI optical configuration, our prototype interferometer doesn't employ the slit nor the cylindrical lens in front of the detector array. In fact, in the developed version a complete 2-D image of the observed scene is acquired with superimposed the autocorrelation modulation pattern. The main feature is that we need acquire as many frames as the number of photosensitive elements. For example, if we utilize a detector array with 512 pixels, it is necessary to acquire a set of 512 records to reconstruct the complete autocorrelation function of each scene pixel. It is clear that the requested data-rate is very high. Figuré 2 shows a picture of the developed instrument. Figure 2. Picture of the developed instrument The characteristics of the CCD camera used to spatially resolve the interferogram are listed in Table 3. Type: CCD frame-transfer with anti-blooming, TH7888A 1024 x 1024 Number of pixel: Pixel size 14 um x 14 um 430 nm-1000 nm @QE>3% Spectral range: Responsivity: 23DN/(nJ em^) @450 nm 18% @680 nm Dynamic range: 3200:1 Maximum frame/rate: | 60 fps Digitalization: 12 bit Table 3. Characteristics of the frame grabber used to spatially resolve the interferogram record In our case, the data cube of a typical measurement contains more than 1 million data points for a total size of 2 MB before cosine transform. 3. PHYSICAL BACKGORUND In a Fourier Transform Spectrometer (FTS) the acquired. physical information is the interferogram /(OPD), which depends on OPD values according to the following fundamental law (Barnes, 1985; Okamoto et al, 1984): 19 (k I(OPD) = | ) [1+ cos(2nkOPD dk (1) 2 where [1 (k) interferometer, OPD is the optical path difference introduced by the BS in the considered propagation direction, k =14A is the wavenumber and the integration takes into account for a non-monochromatic light spectrum. is the intensity of the ray entering the

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