Dr. James J. Butler Profile

Dr. James J. Butler

EOS Calibration Scientist at NASA Goddard Space Flight Ctr

SPIE Involvement:

Conference Chair | Conference Co-Chair | Conference Program Committee | Author | Editor

Publications (69)

PROCEEDINGS ARTICLE | September 7, 2018

Characterizations of a KHz pulsed laser detection system

Proc. SPIE. 10764, Earth Observing Systems XXIII

KEYWORDS: Light sources, Tunable lasers, Light emitting diodes, Calibration, Pulsed laser operation

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PROCEEDINGS ARTICLE | September 7, 2018

MODIS and VIIRS on-orbit calibration and characterization using observations from spacecraft pitch maneuvers

Proc. SPIE. 10764, Earth Observing Systems XXIII

KEYWORDS: Mirrors, MODIS, Sensors, Calibration, Spatial resolution, Space operations, Sensor calibration

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PROCEEDINGS ARTICLE | September 7, 2018

JPSS-1 VIIRS solar diffuser witness sample BRF calibration using a table-top goniometer at NASA GSFC

Proc. SPIE. 10764, Earth Observing Systems XXIII

KEYWORDS: Light sources, Indium gallium arsenide, Sensors, Calibration, Silicon, Lamps, Reflectivity, Semiconductor lasers, Bidirectional reflectance transmission function, Diffusers

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SPIE Conference Volume | November 21, 2017

Earth Observing Systems XXII

PROCEEDINGS ARTICLE | September 5, 2017

JPSS-1 VIIRS RSB sensor spectral response calibration and its applications

Proc. SPIE. 10402, Earth Observing Systems XXII

KEYWORDS: Near infrared, Visible radiation, Radio optics, Sensors, Calibration, Reflectivity, Spectral calibration, Transmittance, Sensor calibration, Bandpass filters

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PROCEEDINGS ARTICLE | September 5, 2017

Establishing BRDF calibration capabilities through shortwave infrared

Proc. SPIE. 10402, Earth Observing Systems XXII

KEYWORDS: Short wave infrared radiation, Data modeling, Calibration, Satellites, Remote sensing, Reflectivity, Bidirectional reflectance transmission function, Diffusers, Infrared radiation, Shortwaves

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SPIE Conference Volume | October 18, 2016

Earth Observing Systems XXI

PROCEEDINGS ARTICLE | September 19, 2016

Preliminary results of BTDF calibration of transmissive solar diffusers for remote sensing

Proc. SPIE. 9972, Earth Observing Systems XXI

KEYWORDS: Near infrared, Sensors, Calibration, Satellites, Ultraviolet radiation, Remote sensing, Reflectivity, Bidirectional reflectance transmission function, Diffusers, Transmittance

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SPIE Conference Volume | August 5, 2016

Earth Observing Missions and Sensors: Development, Implementation, and Characterization IV

PROCEEDINGS ARTICLE | May 2, 2016

Global space-based inter-calibration system reflective solar calibration reference: from Aqua MODIS to S-NPP VIIRS

Proc. SPIE. 9881, Earth Observing Missions and Sensors: Development, Implementation, and Characterization IV

KEYWORDS: MODIS, Sensors, Calibration, Satellites, Reflectivity, Sensor performance, Bidirectional reflectance transmission function, Domes, Diffusers, Sensor calibration

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PROCEEDINGS ARTICLE | May 2, 2016

JPSS-1 VIIRS pre-launch radiometric performance

Proc. SPIE. 9881, Earth Observing Missions and Sensors: Development, Implementation, and Characterization IV

KEYWORDS: Long wavelength infrared, Signal to noise ratio, Electronics, Seaborgium, Polarization, Sensors, Calibration, Reflectivity, Attenuators, Stray light

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SPIE Conference Volume | October 5, 2015

Earth Observing Systems XX

PROCEEDINGS ARTICLE | September 11, 2015

Characterization and application of a LED-driven integrating sphere source

Proc. SPIE. 9607, Earth Observing Systems XX

KEYWORDS: Light sources, Tunable lasers, Light emitting diodes, Optical spheres, Polarization, Sensors, Silicon, Interference (communication), Amplifiers, Integrating spheres

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PROCEEDINGS ARTICLE | September 11, 2015

Assessment of MODIS and VIIRS solar diffuser on-orbit degradation

Proc. SPIE. 9607, Earth Observing Systems XX

KEYWORDS: Near infrared, MODIS, Sun, Sensors, Signal attenuation, Calibration, Reflectivity, Diffusers, Radiometry, Space operations

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PROCEEDINGS ARTICLE | September 8, 2015

VIIRS/J1 polarization narrative

Proc. SPIE. 9607, Earth Observing Systems XX

KEYWORDS: Optical filters, Mirrors, Polarization, Sensors, Calibration, Polarizers, Integrating spheres, Radiometry, Stray light, Bandpass filters

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PROCEEDINGS ARTICLE | September 8, 2015

JPSS-1 VIIRS pre-launch radiometric performance

Proc. SPIE. 9607, Earth Observing Systems XX

KEYWORDS: Long wavelength infrared, Signal to noise ratio, Infrared sensors, Seaborgium, Polarization, Sensors, Calibration, Reflectivity, Attenuators, Stray light

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SPIE Conference Volume | October 13, 2014

Earth Observing Systems XIX

PROCEEDINGS ARTICLE | September 26, 2014

CLARREO calibration uncertainty assessment tool: status and path forward

Proc. SPIE. 9218, Earth Observing Systems XIX

KEYWORDS: Sun, Sensors, Calibration, Remote sensing, Reflectivity, Climate change, Attenuators, Stray light, Climatology, Environmental sensing

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SPIE Conference Volume | October 18, 2013

Earth Observing Systems XVIII

PROCEEDINGS ARTICLE | October 16, 2013

MODIS and VIIRS lunar observations and applications

Proc. SPIE. 8889, Sensors, Systems, and Next-Generation Satellites XVII

KEYWORDS: Mirrors, MODIS, Sensors, Calibration, Reflectivity, Modulation transfer functions, Spatial resolution, Space operations, Sensor calibration, Earth observing sensors

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PROCEEDINGS ARTICLE | September 23, 2013

Characterization of a radiometric monitoring system for NASA code 618's SIRCUS-G

Proc. SPIE. 8866, Earth Observing Systems XVIII

KEYWORDS: Indium gallium arsenide, Optical spheres, Phase modulation, Sensors, Calibration, Silicon, Integrating spheres, Radiometry, Laser systems engineering, Amplitude modulation

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PROCEEDINGS ARTICLE | September 23, 2013

Improvements of VIIRS and MODIS solar diffuser and lunar calibration

Proc. SPIE. 8866, Earth Observing Systems XVIII

KEYWORDS: Near infrared, Mirrors, MODIS, Sun, Modulation, Sensors, Signal attenuation, Calibration, Reflectivity, Diffusers

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PROCEEDINGS ARTICLE | November 19, 2012

Comparison of MODIS and VIIRS On-board blackbody Performance

Proc. SPIE. 8533, Sensors, Systems, and Next-Generation Satellites XVI

KEYWORDS: Staring arrays, Mirrors, MODIS, Sensors, Calibration, Black bodies, Radiometry, Space operations, Temperature metrology

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PROCEEDINGS ARTICLE | October 15, 2012

NPP VIIRS on-orbit calibration and characterization using the moon

Proc. SPIE. 8510, Earth Observing Systems XVII

KEYWORDS: Staring arrays, Near infrared, Mirrors, Visible radiation, Safety, MODIS, Sensors, Calibration, Reflectivity, Space operations

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PROCEEDINGS ARTICLE | October 15, 2012

VIIRS on-orbit optical anomaly: investigation, analysis, root cause determination and lessons learned

Proc. SPIE. 8510, Earth Observing Systems XVII

KEYWORDS: Near infrared, Mirrors, Contamination, MODIS, Sensors, Satellites, Ultraviolet radiation, Tungsten, Coating, Reflectivity

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PROCEEDINGS ARTICLE | October 15, 2012

An overview of Suomi NPP VIIRS calibration maneuvers

Proc. SPIE. 8510, Earth Observing Systems XVII

KEYWORDS: Infrared imaging, Mirrors, Visible radiation, MODIS, Sensors, Calibration, Reflectivity, Diffusers, Infrared radiation, Space operations

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The first Visible Infrared Imager Radiometer Suite (VIIRS) instrument was successfully launched on-board the Suomi National Polar-orbiting Partnership (SNPP) spacecraft on October 28, 2011. Suomi NPP VIIRS observations are made in 22 spectral bands, from the visible (VIS) to the long-wave infrared (LWIR), and are used to produce 22 Environmental Data Records (EDRs) with a broad range of scientific applications. The quality of these VIIRS EDRs strongly depends on the quality of its calibrated and geo-located Sensor Date Records (SDRs). Built with a strong heritage to the NASA’s EOS MODerate resolution Imaging Spectroradiometer (MODIS) instrument, the VIIRS is calibrated on-orbit using a similar set of on-board calibrators (OBC), including a solar diffuser (SD) and solar diffuser stability monitor (SDSM) system for the reflective solar bands (RSB) and a blackbody (BB) for the thermal emissive bands (TEB). Onorbit maneuvers of the SNPP spacecraft provide additional calibration and characterization data from the VIIRS instrument which cannot be obtained pre-launch and are required to produce the highest quality SDRs. These include multiorbit yaw maneuvers for the characterization of SD and SDSM screen transmission, quasi-monthly roll maneuvers to acquire lunar observations to track sensor degradation in the visible through shortwave infrared, and a driven pitch-over maneuver to acquire multiple scans of deep space to determine TEB response versus scan angle (RVS). This paper provides an overview of these three SNPP calibration maneuvers. Discussions are focused on their potential calibration and science benefits, pre-launch planning activities, and on-orbit scheduling and implementation strategies. Results from calibration maneuvers performed during the Intensive Calibration and Validation (ICV) period for the VIIRS sensor are illustrated. Also presented in this paper are lessons learned regarding the implementation of calibration spacecraft maneuvers on follow-on missions.

PROCEEDINGS ARTICLE | October 15, 2012

Preliminary assessment of Suomi-NPP VIIRS on-orbit radiometric performance

Proc. SPIE. 8510, Earth Observing Systems XVII

KEYWORDS: Signal to noise ratio, Mirrors, MODIS, Data modeling, Sensors, Calibration, Ultraviolet radiation, Reflectivity, Bidirectional reflectance transmission function, Space operations

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SPIE Conference Volume | September 27, 2012

Earth Observing Systems XVII

SPIE Journal Paper | November 1, 2011

Development and performance of a filter radiometer monitor system for integrating sphere sources

Ding, Leibo , Cooper, John , Smith, Gilbert , Kowalewski, Matthew , Barnes, Robert , Waluschka, Eugene , Butler, James

OE Vol. 50 Issue 11

KEYWORDS: Sensors, Optical spheres, Phase modulation, Integrating spheres, Radiometry, Lamps, Calibration, Indium gallium arsenide, Optical filters, Silicon

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PROCEEDINGS ARTICLE | October 3, 2011

SWIR calibration of Spectralon reflectance factor

Proc. SPIE. 8176, Sensors, Systems, and Next-Generation Satellites XV

KEYWORDS: Short wave infrared radiation, Indium gallium arsenide, Sensors, Calibration, Ultraviolet radiation, Reflectivity, Photodiodes, Receivers, Bidirectional reflectance transmission function, Diffusers

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PROCEEDINGS ARTICLE | September 14, 2011

Results from solar reflective band end-to-end testing for VIIRS F1 sensor using T-SIRCUS

Proc. SPIE. 8153, Earth Observing Systems XVI

KEYWORDS: Infrared sensors, MODIS, Aerospace engineering, Sensors, Calibration, Reflectivity, Collimators, Diffusers, Integrating spheres, Radiometry

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SPIE Conference Volume | September 13, 2011

Earth Observing Systems XVI

PROCEEDINGS ARTICLE | November 4, 2010

Initial studies of the bidirectional reflectance distribution function of carbon nanotube structures for stray light control applications

Proc. SPIE. 7862, Earth Observing Missions and Sensors: Development, Implementation, and Characterization

KEYWORDS: Titanium, Silicon, Light scattering, Reflectivity, Optical testing, Bidirectional reflectance transmission function, Diffusers, Stray light, Stray light control, Carbon nanotubes

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PROCEEDINGS ARTICLE | October 29, 2010

Comparison of two methodologies for calibrating satellite instruments in the visible and near infrared

Proc. SPIE. 7862, Earth Observing Missions and Sensors: Development, Implementation, and Characterization

KEYWORDS: Near infrared, Visible radiation, Optical spheres, Sensors, Calibration, Satellites, Manufacturing, Lamps, Diffusers, Integrating spheres

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PROCEEDINGS ARTICLE | October 14, 2010

Characterization of a double monochromator

Proc. SPIE. 7826, Sensors, Systems, and Next-Generation Satellites XIV

KEYWORDS: Optical spheres, Sensors, Calibration, Ultraviolet radiation, Mercury, Lamps, Integrating spheres, Radiometry, Monochromators, Stray light

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PROCEEDINGS ARTICLE | August 31, 2010

Multiwalled carbon nanotubes for stray light suppression in space flight instruments

Proc. SPIE. 7761, Carbon Nanotubes, Graphene, and Associated Devices III

KEYWORDS: Mirrors, Aerospace engineering, Silicon, Light scattering, Reflectivity, Bidirectional reflectance transmission function, Nanoimprint lithography, Stray light, Stray light control, Carbon nanotubes

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Observations of the Earth are extremely challenging; its large angular extent floods scientific instruments with high flux within and adjacent to the desired field of view. This bright light diffracts from instrument structures, rattles around and invariably contaminates measurements. Astrophysical observations also are impacted by stray light that obscures very dim objects and degrades signal to noise in spectroscopic measurements. Stray light is controlled by utilizing low reflectance structural surface treatments and by using baffles and stops to limit this background noise. In 2007 GSFC researchers discovered that Multiwalled Carbon Nanotubes (MWCNTs) are exceptionally good absorbers, with potential to provide order-of-magnitude improvement over current surface treatments and a resulting factor of 10,000 reduction in stray light when applied to an entire optical train. Development of this technology will provide numerous benefits including: a.) simplification of instrument stray light controls to achieve equivalent performance, b.) increasing observational efficiencies by recovering currently unusable scenes in high contrast regions, and c.) enabling low-noise observations that are beyond current capabilities. Our objective was to develop and apply MWCNTs to instrument components to realize these benefits. We have addressed the technical challenges to advance the technology by tuning the MWCNT geometry using a variety of methods to provide a factor of 10 improvement over current surface treatments used in space flight hardware. Techniques are being developed to apply the optimized geometry to typical instrument components such as spiders, baffles and tubes. Application of the nanostructures to alternate materials (or by contact transfer) is also being investigated. In addition, candidate geometries have been tested and optimized for robustness to survive integration, testing, launch and operations associated with space flight hardware. The benefits of this technology extend to space science where observations of extremely dim objects require suppression of stray light.

SPIE Conference Volume | August 25, 2010

Earth Observing Systems XV

PROCEEDINGS ARTICLE | August 21, 2009

Progress in BRDF calibration measurements in the SWIR

Proc. SPIE. 7452, Earth Observing Systems XIV

KEYWORDS: Short wave infrared radiation, Light sources, Data modeling, Sensors, Calibration, Reflectivity, Photodiodes, Receivers, Bidirectional reflectance transmission function, Diffusers

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PROCEEDINGS ARTICLE | August 21, 2009

MODIS solar reflective calibration traceability

Proc. SPIE. 7452, Earth Observing Systems XIV

KEYWORDS: Near infrared, Mirrors, MODIS, Sensors, Calibration, Reflectivity, Diffusers, Sensor calibration, Climatology, Environmental sensing

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PROCEEDINGS ARTICLE | August 21, 2009

Development of a filter radiometer monitor system for integrating sphere sources

Proc. SPIE. 7452, Earth Observing Systems XIV

KEYWORDS: Indium gallium arsenide, Optical spheres, Phase modulation, Sensors, Calibration, Silicon, Lamps, Integrating spheres, Radiometry, Amplitude modulation

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SPIE Conference Volume | August 21, 2009

Earth Observing Systems XIV

PROCEEDINGS ARTICLE | October 9, 2008

Calibration of a radiance standard for the NPP/OMPS instrument

Proc. SPIE. 7106, Sensors, Systems, and Next-Generation Satellites XII

KEYWORDS: Optical spheres, Aerospace engineering, Calibration, Spectroscopy, Remote sensing, Lamps, Diffusers, Integrating spheres, Radiometry, Standards development

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SPIE Conference Volume | August 20, 2008

Earth Observing Systems XIII

PROCEEDINGS ARTICLE | August 20, 2008

BRDF study of gray-scale Spectralon

Proc. SPIE. 7081, Earth Observing Systems XIII

KEYWORDS: Sensors, Calibration, Satellites, Remote sensing, Light scattering, Reflectivity, Vegetation, Bidirectional reflectance transmission function, Diffusers, Systems modeling

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PROCEEDINGS ARTICLE | October 17, 2007

Modeling spectral effects in Earth-observing satellite instruments

Proc. SPIE. 6744, Sensors, Systems, and Next-Generation Satellites XI

KEYWORDS: Sensors, Calibration, Satellites, Spectroscopy, Transmittance, Atmospheric modeling, Lawrencium, Spectral models, Instrument modeling, Absorption

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We present a simple, spreadsheet-based model to examine the effects of the spectral response functions of individual instrument bands on their measurements of top-of-the-atmosphere radiances. The model uses spectral radiances at 1 nm resolution from the near ultraviolet to the shortwave infrared at wavelengths from 300 nm to 2500 nm, convolving them with the spectral responses of the bands to calculate band-average spectral radiances. For on-orbit calibration purposes, the model uses nominal solar irradiance and lunar albedo spectra to provide saturation, diffuser, and lunar radiances for the bands. For prelaunch calibration purposes, the model uses a 2850K Planck function, normalized to a maximum value of unity, to approximate the spectral shape from a laboratory integrating sphere source. For Earth-exiting radiances, the model uses nominal radiance spectra over a blue ocean, a desert, and a grassland. These spectra are provided with the effects of atmospheric trace gas absorption removed. In addition, the model includes a trace gas transmittance spectrum that can be modified as a function of airmass. Currently, a spectrum with an airmass of 2.4 is used. In the model, this transmittance spectrum is combined with the three Earth-exiting radiance spectra to provide top-of-the-atmosphere radiance spectra both with and without trace gas absorption features. Here we use the model to investigate three types of spectral response features. The first study involves the out-of-band response from one of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) bands. Using the model, we demonstrate a technique to correct for the effect of that response on measurements of Earth-exiting radiances. The second study shows the effect of in-band spectral differences in an instrument band with multiple detectors. In this example, the effects are small, but differ with the type of Earth scene and with the amount of atmospheric trace gas absorption. On-orbit corrections for portions these detector-to-detector spectral differences are possible. However, at some level these differences will cause a residual striping in the band's measurements that cannot be removed. The final study examines measurements by a proposed multispectral grating-based spectrometer of the wavelength region near 760 nm, where there is a substantial absorption feature from atmospheric oxygen. Based on the bandwidth and wavelength spacing of the instrument's bands, we investigate the use of the absorption feature to provide a wavelength calibration for the instrument. This model provides a tool for use in the design of new satellite instruments. In addition, it is possible to use the model to help mitigate the effects of actual spectral response features in instrument bands after those features are revealed during prelaunch characterization.

PROCEEDINGS ARTICLE | September 26, 2007

Validation of radiometric standards for the laboratory calibration of reflected-solar Earth-observing satellite instruments

Proc. SPIE. 6677, Earth Observing Systems XII

KEYWORDS: Short wave infrared radiation, Sensors, Calibration, Satellites, Reflectivity, Bidirectional reflectance transmission function, Infrared radiation, Integrating spheres, Radiometry, Shortwaves

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PROCEEDINGS ARTICLE | September 26, 2007

System-level pre-launch calibration of onboard solar diffusers

Proc. SPIE. 6677, Earth Observing Systems XII

KEYWORDS: Telescopes, Optical spheres, Sensors, Calibration, Satellites, Reflectivity, Collimators, Diffusers, Integrating spheres, Alternate lighting of surfaces

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SPIE Conference Volume | September 19, 2007

Earth Observing Systems XII

PROCEEDINGS ARTICLE | September 7, 2006

Bandwidth and spectral stray light effects in the NASA GSFC Radiometric Calibration Facility primary transfer radiometer

Proc. SPIE. 6296, Earth Observing Systems XI

KEYWORDS: Optical spheres, Scattering, Sensors, Calibration, Lamps, Integrating spheres, Radiometry, Stray light, Signal detection, Free electron lasers

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PROCEEDINGS ARTICLE | September 7, 2006

Comparison between laboratory and airborne BRDF measurements for remote sensing

Proc. SPIE. 6296, Earth Observing Systems XI

KEYWORDS: Solar radiation models, Backscatter, Scattering, Sensors, Calibration, Remote sensing, Light scattering, Reflectivity, Vegetation, Bidirectional reflectance transmission function

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SPIE Conference Volume | September 5, 2006

Earth Observing Systems XI

PROCEEDINGS ARTICLE | August 22, 2005

Use of the moon as a calibration reference for NPP VIIRS

Proc. SPIE. 5882, Earth Observing Systems X

KEYWORDS: MODIS, Sensors, Calibration, Satellites, Reflectivity, Diffusers, Space operations, Instrument modeling, Alternate lighting of surfaces, Reverse modeling

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PROCEEDINGS ARTICLE | August 22, 2005

The effect of speckle on BRDF measurements

Proc. SPIE. 5882, Earth Observing Systems X

KEYWORDS: Laser sources, Telescopes, Light sources, Speckle, Sensors, Calibration, Reflectivity, Speckle pattern, Bidirectional reflectance transmission function, Diffusers

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SPIE Conference Volume | August 22, 2005

Earth Observing Systems X

SPIE Journal Paper | March 1, 2005

Bidirectional reflectance distribution function and directional-hemispherical reflectance of a martian regolith simulant

Georgiev, Georgi , Butler, James

OE Vol. 44 Issue 03

KEYWORDS: Bidirectional reflectance transmission function, Scattering, Reflectivity, Light scattering, Sensors, Optical engineering, Optical spheres, Calibration, Mars, Receivers

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PROCEEDINGS ARTICLE | November 4, 2004

Radiometric characterization of the NASA GSFC radiometric calibration facility primary transfer radiometer

Proc. SPIE. 5570, Sensors, Systems, and Next-Generation Satellites VIII

KEYWORDS: Optical spheres, Radio optics, Sensors, Calibration, Luminescence, Silicon, Lamps, Integrating spheres, Radiometry, Stray light

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PROCEEDINGS ARTICLE | November 4, 2004

Use of the Moon as a reference for satellite-based climate change measurements

Proc. SPIE. 5570, Sensors, Systems, and Next-Generation Satellites VIII

KEYWORDS: MODIS, Data modeling, Calibration, Satellites, Reflectivity, Climate change, Phase measurement, Space operations, Instrument modeling, Reverse modeling

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The United States Geologic Survey (USGS) has developed a lunar irradiance model for comparison with on-orbit sattelite instruments. The comparisons are given as the percent difference of the satellite measurements from the model-generated lunar irradiances. For users of the USGS lunar model, details of the inner operation of the model are unknown. That operation is not examined here. Rather, we examine the outputs of the model. We treat the model-generated lunar irradiances as independent data sets, with each covering only a limited range of phase angles in the comparison with an individual satellite instrument. We correct the model irradiances to standard Sun-Moon and Moon-instrument distances and to fixed values for the phase and libration angles. These same corrections can be applied to the measuements by the comparison satellite instrument. For the model outputs examined here, the time trends in the corrected irradiances differ from zero change by less that 0.0014% per thousand days, and the residual scatter in the results is 0.013% (1σ). There are no apparent oscillations in the time series. At this level, the lunar model should provide an adequate reference for instruments that measure long-term climate change. The model outputs here correspond to the bands from the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) instrument and to the phase angle range for the SeaWiFS lunar measurements, which is from 5° to 10°, both before and after full phase. Similar results have been obtained for model outputs corresponding to lunar measurements from the Moderate Resolution Imaging Sectroradiometer (MODIS) instruments onboard the Terra and Aqua spacecraft. This technique is applicable to other instruments that measure at wavelengths from 400 nm to 2500 nm since, in addition to the relative spectral responses of the instrument's bands, the only requirements for the model are the time and location of the instrument's lunar measurements.

PROCEEDINGS ARTICLE | November 4, 2004

The effect of incident light polarization on spectralon BRDF measurements

Proc. SPIE. 5570, Sensors, Systems, and Next-Generation Satellites VIII

KEYWORDS: Polarization, Scattering, Sensors, Calibration, Satellites, Ultraviolet radiation, Light scattering, Reflectivity, Bidirectional reflectance transmission function, Diffusers

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PROCEEDINGS ARTICLE | October 26, 2004

Long-term comparison of spectralon BRDF measurements in the ultraviolet

Proc. SPIE. 5542, Earth Observing Systems IX

KEYWORDS: Aerospace engineering, Sensors, Calibration, Satellites, Ultraviolet radiation, Remote sensing, Bidirectional reflectance transmission function, Diffusers, Target acquisition, Ozone

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SPIE Conference Volume | October 26, 2004

Earth Observing Systems IX

PROCEEDINGS ARTICLE | November 10, 2003

Preliminary results of aperture-area comparison for exo-atmospheric solar irradiance

Proc. SPIE. 5151, Earth Observing Systems VIII

KEYWORDS: Microscopes, Metrology, Solar energy, Satellites, Climate change, Radiometry, Earth's atmosphere, Solar radiation, Environmental sensing, Standards development

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PROCEEDINGS ARTICLE | October 16, 2003

The effect of weave orientation on the BRDF of tarp samples

Proc. SPIE. 5189, Surface Scattering and Diffraction III

KEYWORDS: Near infrared, Light sources, Optical spheres, Sensors, Calibration, Ultraviolet radiation, Error analysis, Reflectivity, Receivers, Bidirectional reflectance transmission function

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PROCEEDINGS ARTICLE | April 8, 2003

Comparison of ultraviolet bidirectional reflectance distribution function (BRDF) measurements of diffusers used in the calibration of the Total Ozone Mapping Spectrometer (TOMS)

Proc. SPIE. 4881, Sensors, Systems, and Next-Generation Satellites VI

KEYWORDS: Sensors, Calibration, Spectroscopy, Ultraviolet radiation, Receivers, Bidirectional reflectance transmission function, Diffusers, Ozone, Scatter measurement, Telescopic pixel displays

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PROCEEDINGS ARTICLE | April 8, 2003

Integrating sphere source monitoring and stability data

Proc. SPIE. 4881, Sensors, Systems, and Next-Generation Satellites VI

KEYWORDS: Optical spheres, Sensors, Calibration, Coating, Lamps, Aluminum, Integrating spheres, Radiometry, Signal detection, Temperature metrology

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PROCEEDINGS ARTICLE | October 22, 2002

Bidirectional reflectance distribution function and hemispherical reflectance of JSC MARS-1

Proc. SPIE. 4780, Surface Scattering and Diffraction for Advanced Metrology II

KEYWORDS: Near infrared, Optical spheres, Sensors, Calibration, Ultraviolet radiation, Error analysis, Reflectivity, Receivers, Bidirectional reflectance transmission function, Scatter measurement

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PROCEEDINGS ARTICLE | December 28, 1999

Radiometric measurement comparisons using transfer radiometers in support of the calibration of NASA's Earth Observing System (EOS) sensors

Proc. SPIE. 3870, Sensors, Systems, and Next-Generation Satellites III

KEYWORDS: Short wave infrared radiation, Optical spheres, Sensors, Calibration, Satellites, Remote sensing, Lamps, Infrared radiation, Integrating spheres, Radiometry

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EOS satellite instruments operating in the visible through the shortwave infrared wavelength regions (from 0.4 micrometer to 2.5 micrometer) are calibrated prior to flight for radiance response using integrating spheres at a number of instrument builder facilities. The traceability of the radiance produced by these spheres with respect to international standards is the responsibility of the instrument builder, and different calibration techniques are employed by those builders. The National Aeronautics and Space Administration's (NASA's) Earth Observing System (EOS) Project Science Office, realizing the importance of preflight calibration and cross-calibration, has sponsored a number of radiometric measurement comparisons, the main purpose of which is to validate the radiometric scale assigned to the integrating spheres by the instrument builders. This paper describes the radiometric measurement comparisons, the use of stable transfer radiometers to perform the measurements, and the measurement approaches and protocols used to validate integrating sphere radiances. Stable transfer radiometers from the National Institute of Standards and Technology, the University of Arizona Optical Sciences Center Remote Sensing Group, NASA's Goddard Space Flight Center, and the National Research Laboratory of Metrology in Japan, have participated in these comparisons. The approaches used in the comparisons include the measurement of multiple integrating sphere lamp levels, repeat measurements of select lamp levels, the use of the stable radiometers as external sphere monitors, and the rapid reporting of measurement results. Results from several comparisons are presented. The absolute radiometric calibration standard uncertainties required by the EOS satellite instruments are typically in the plus or minus 3% to plus or minus 5% range. Preliminary results reported during eleven radiometric measurement comparisons held between February 1995 and May 1998 have shown the radiance of integrating spheres agreed to within plus or minus 2.5% from the average at blue wavelengths and to within plus or minus 1.7% from the average at red and near infrared wavelengths. This level of agreement lends confidence in the use of the transfer radiometers in validating the radiance scales assigned by EOS instrument calibration facilities to their integrating sphere sources.

PROCEEDINGS ARTICLE | October 8, 1998

Intercomparisons of reflectance measurements

Proc. SPIE. 3425, Optical Diagnostic Methods for Inorganic Transmissive Materials

KEYWORDS: Statistical analysis, Radio optics, Diffuse reflectance spectroscopy, Sensors, Remote sensing, Reflectivity, Optical testing, Bidirectional reflectance transmission function, Aluminum, Standards development

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PROCEEDINGS ARTICLE | November 11, 1996

EOS AM-1 preflight radiometric measurement comparison using the Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) visible/near-infrared integrating sphere

Proc. SPIE. 2820, Earth Observing System

KEYWORDS: Optical filters, Optical spheres, Sensors, Calibration, Satellites, Silicon, Lamps, Black bodies, Integrating spheres, Radiometry

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PROCEEDINGS ARTICLE | September 14, 1994

Comparisons of UV spectral radiance calibrations of SBUV/2 type ozone monitoring instruments and traceability to NIST

Proc. SPIE. 2282, Ultraviolet Technology V

KEYWORDS: Optical spheres, Calibration, Ultraviolet radiation, Lamps, Spectral calibration, Bidirectional reflectance transmission function, Black bodies, Diffusers, Spherical lenses, Free electron lasers

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