Spectral calibration of atmosphere hyper-spectral resolution infrared sounder

The field-imaging far-infrared line spectrometer (FIFI-LS) is a science instrument for the Stratospheric Observatory for Infrared Astronomy (SOFIA). FIFI-LS allows simultaneous observations in two spectral channels. The “blue” channel is sensitive from 51[Formula: see text][Formula: see text]m to 125[Formula: see text][Formula: see text]m and the “red” channel from 115[Formula: see text][Formula: see text]m to 203[Formula: see text][Formula: see text]m. The instantaneous spectral coverage is 1000–3000[Formula: see text]km/s in the blue and 800–2500[Formula: see text]km/s in the red channel with a spectral resolution between 150[Formula: see text]km/s and 600[Formula: see text]km/s. Each spectral channel observes a field of five by five spatial pixels on the sky. The pixel size in the blue channel is 6.14 by 6.25 square arc seconds and it is 12.2 by 12.5 square arc seconds in the red channel. FIFI-LS has been operating on SOFIA since 2014. It is available to the astronomical community as a facility science instrument. We present the results of the spectral and spatial characterization of the instrument based on laboratory measurements. This includes the measured spectral resolution and examples of the line spread function in the spectral domain. In the spatial domain, a model of the instrument’s point spread function (PSF) and the description of a second pass ghost are presented. We also provide an overview of the procedures used to measure the instrument’s field of view geometry and spectral calibration. The spectral calibration yields an accuracy of 15–60[Formula: see text]km/s depending on wavelength.

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Laboratory spectral calibration of the TanSat atmospheric carbon dioxide grating spectrometer

Geoscientific Instrumentation Methods and Data Systems ◽

10.5194/gi-7-245-2018 ◽

2018 ◽

Vol 7 (3) ◽

pp. 245-252 ◽

Cited By ~ 5

Author(s):

Zhongdong Yang ◽

Yuquan Zhen ◽

Zenshan Yin ◽

Chao Lin ◽

Yanmeng Bi ◽

...

Keyword(s):

Carbon Dioxide ◽

Spectral Resolution ◽

Line Shape ◽

Atmospheric Carbon Dioxide ◽

Near Infrared ◽

Shape Function ◽

Grating Spectrometer ◽

Spectral Calibration ◽

Atmospheric Carbon ◽

Line Shape Function

Abstract. TanSat is a key satellite mission in the Chinese Earth Observation program and is designed to measure the global atmospheric column-averaged dry-air CO2 mole fraction by measuring the visible and near-infrared solar-reflected spectra. The first Chinese super-high-resolution grating spectrometer for measuring atmospheric CO2 is aboard TanSat. This spectrometer is a suite incorporating three grating spectrometers that make coincident measurements of reflected sunlight in the near-infrared CO2 band near 1.61 and 2.06 µm and in the molecular oxygen (O2) A-band at 0.76 µm. The spectral resolving power (λ∕Δλ) values are ∼19 000, ∼12 800, and ∼12 250 in the O2 A-band, and the weak and strong absorption bands of CO2, respectively. This paper describes the prelaunch spectral calibration of the atmospheric carbon dioxide grating spectrometer aboard TanSat. Several critical aspects of the spectrometer, including the spectral resolution, spectral dispersion, and the instrument line shape function of each channel, which are directly related to producing the Level 1 products are evaluated in this paper. The instrument line shape function of the spectrometer is notably symmetrical and perfectly consistent across all channels in the three bands. The symmetry is better then 99.99 %, and the consistency in the worst case is better then 99.97 %, 99.98 %, and 99.98 % in the O2 A, WCO2, and SCO2 bands, respectively. The resulting variations in the spectral calibrations and the radiometric response errors are negligible. The spectral resolution characterizations meet the mission requirements. The spectral dispersions have excellent consistency in the spatial dimension of each band, and there is good linearity in the spectral dimension of each band. The RMS errors of the fitting residuals are 0.9, 1, and 0.7 pm in the O2 A-band, the WCO2 band, and the SCO2 band, respectively. Taken together, these results suggest that the spectral characterizations of the spectrometer aboard TanSat meet the mission requirements.

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The Application of Hyper-Spectral Remote Sensing in Cultural Relic Conservation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.446-449.3798 ◽

2012 ◽

Vol 446-449 ◽

pp. 3798-3802

Author(s):

Xin Lu ◽

Miao Le Hou ◽

Yun Gang Hu

Keyword(s):

Remote Sensing ◽

Spectral Resolution ◽

High Spectral Resolution ◽

Basic Principles ◽

New Science ◽

Hyper Spectral ◽

Potential Applications ◽

Cultural Relic ◽

New Perspective ◽

Non Destructive

Hyper-spectral remote sensing as new science and technology, is gradually applied to various fields. The technology has the technical advantages which are the high spectral resolution and non-destructive detection. These provide a new perspective for the research and protection of cultural relics. This paper firstly described the basic principles of hyper-spectral technology and its advantages, then stated the main applications of the technology in the conservation work, and at last, briefly summarized its limitations and potential applications.

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Scene-based spectral calibration assessment of high spectral resolution imaging spectrometers

Optics Express ◽

10.1364/oe.17.011594 ◽

2009 ◽

Vol 17 (14) ◽

pp. 11594 ◽

Cited By ~ 35

Author(s):

Luis Guanter ◽

Karl Segl ◽

Bernhard Sang ◽

Luis Alonso ◽

Hermann Kaufmann ◽

...

Keyword(s):

Spectral Resolution ◽

High Spectral Resolution ◽

Spectral Calibration ◽

Resolution Imaging

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Research on spectral calibration for hyper-spectral imager

10.1117/12.966415 ◽

2012 ◽

Author(s):

Yong-xiang Guo ◽

Yong-qiang Li ◽

Xiao-ying Zong

Keyword(s):

Spectral Calibration ◽

Hyper Spectral ◽

Spectral Imager

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Stress Mapping in Silicon: Advantages of Using a Raman Spectrometer with a Single Dispersive Stage

Applied Spectroscopy ◽

10.1366/0003702021955312 ◽

2002 ◽

Vol 56 (5) ◽

pp. 560-563 ◽

Cited By ~ 17

Author(s):

E. Bonera ◽

M. Fanciulli ◽

D. N. Batchelder

Keyword(s):

Raman Spectroscopy ◽

Spectral Resolution ◽

Laser Plasma ◽

High Stability ◽

Collection Efficiency ◽

Raman Spectrometer ◽

Fast Acquisition ◽

Spectral Calibration ◽

Stress Mapping ◽

Anti Stokes

Stress is a major concern in microelectronic circuit production and Raman spectroscopy has proved to be an outstanding method for mapping it in silicon. In the literature, a configuration with two or three spectral dispersive stages is usually employed. By using a Raman spectrometer with a single dispersive stage, however, it is possible to have higher collection efficiency, resulting in fast acquisition and high stability of the system. Although the nominal spectral resolution of such a system is approximately 2 cm−1, we have found that the sensitivity to stress is less than 50 MPa, comparable to other systems with more dispersive stages. For low stress values, less than 100 MPa, the Raman measurements can be affected by the patterning of the sample itself, especially if laser plasma lines are used for spectral calibration. It will be shown that the use of a Raman microscope with a single dispersive stage, enabling simultaneous collection of Stokes and anti-Stokes components, provides a feedback for the reliability of the experiment.

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