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Spectroradiometer

NATURASPEC ULTRA (Manufacturer) · TUHH Open Research · 2026

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Spectroradiometer

Metal Finishing · 1998

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Spectroradiometer.

Changseok Lee (6832547), Liam Redden (20659213), Vivian Eng (22278939) et al. · Figshare · 2025

<div> Purpose To investigate the luminance capacity and achievable threshold levels of commercially employed virtual reality (VR) devices for visual field testing. Methods This two-part study included (1) a literature review of VR headsets used for perimetry with luminance data extracted from technical specifications in publications and manufacturers; and (2) empirical evaluation of three most employed VR headsets in the literature using a custom virtual testing environment. Results Three most employed VR devices for visual field testing were Pico Neo, Oculus Quest, and HTC Vive. The maximum reported luminance was 250 cd/m² for the HTC Vive Pro. Information on luminance measurement was not consistently available, reporting only handheld luminance meters. Empirical measurements show that handheld luminance meters significantly overestimate luminance compared to standard spectroradiometers. Measured luminance varies significantly across aperture size and decreases for peripheral stimuli up to 30 degrees peripherally. Assuming conventional background of 10 cd/m², the best performance with lowest possible thresholding was with HTC Vive at 16dB, corresponding to luminance of 80 cd/m² centrally. Oculus Quest 2 and Pico Neo 3 had minimum threshold of 20dB. Conclusion Commercially available VR devices do not meet luminance requirements or threshold sensitivities for visual field testing. Current VR technology is not designed—nor has the capacity—to threshold at mid-to-low dB ranges, which limits accuracy in diagnosing and monitoring defects seen in glaucoma. Translational Relevance: This study highlights the technical limitations of current commercially available VR devices for visual field testing and significant variables in evaluating luminance performance in these devices. </div>

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resolution imaging spectroradiometer

Xianjun Hao, John J. Qu · 2015

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Process spectroradiometer data.

Changseok Lee (6832547), Liam Redden (20659213), Vivian Eng (22278939) et al. · Figshare · 2025

<div> Purpose To investigate the luminance capacity and achievable threshold levels of commercially employed virtual reality (VR) devices for visual field testing. Methods This two-part study included (1) a literature review of VR headsets used for perimetry with luminance data extracted from technical specifications in publications and manufacturers; and (2) empirical evaluation of three most employed VR headsets in the literature using a custom virtual testing environment. Results Three most employed VR devices for visual field testing were Pico Neo, Oculus Quest, and HTC Vive. The maximum reported luminance was 250 cd/m² for the HTC Vive Pro. Information on luminance measurement was not consistently available, reporting only handheld luminance meters. Empirical measurements show that handheld luminance meters significantly overestimate luminance compared to standard spectroradiometers. Measured luminance varies significantly across aperture size and decreases for peripheral stimuli up to 30 degrees peripherally. Assuming conventional background of 10 cd/m², the best performance with lowest possible thresholding was with HTC Vive at 16dB, corresponding to luminance of 80 cd/m² centrally. Oculus Quest 2 and Pico Neo 3 had minimum threshold of 20dB. Conclusion Commercially available VR devices do not meet luminance requirements or threshold sensitivities for visual field testing. Current VR technology is not designed—nor has the capacity—to threshold at mid-to-low dB ranges, which limits accuracy in diagnosing and monitoring defects seen in glaucoma. Translational Relevance: This study highlights the technical limitations of current commercially available VR devices for visual field testing and significant variables in evaluating luminance performance in these devices. </div>

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Continuously Recording Spectroradiometer*

David L. MacAdam · Journal of the Optical Society of America · 1958

A spectroradiometer is described for recording the spectral distribution of daylight or of any artificial light source that radiates steadily for 3.5 min. Beams from the external source and from an internal standard lamp are deviated alternately through a monochromator to a multiplier phototube. The collimator consists of parallel baffles instead of a mirror or lenses. The amplified signal activates a motor which moves a mirror to attenuate the energy from the internal standard until the beams are equal. The necessary degree of attenuation is then recorded while the wavelength is being changed. The logarithm of the spectral distribution of the internal standard may be added electrically to the logarithm of the measured attenuation to record directly the logarithm of the absolute energy radiated by the sample. The spectral distribution of sources with luminances as low as 1 ft-L have been measured with a half-maximum band width of 10 mμ. The spectral emittance of a variety of phases of daylight and sunlight, at different times of the year and under various weather conditions, as well as of fluorescent lamps, electroluminescent panels, and ultraviolet-excited fluorescent coatings, have been recorded and are summarized here.

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An Airborne Spectroradiometer*

L. G. Mundie, David E. Brown, P. G. Hasell et al. · Journal of the Optical Society of America · 1960

A system is described for acquiring spectroradiometric data concerning objects in space from an airborne platform. The system operates in the 0.25 to 15-μ spectral region; large collecting optics, precise optical tracking, and background discrimination in the entrance optics permit the acquisition of high resolution and sensitivity. Through the use of reflective choppers, dichroic filters, and multiple exit slits, five types of data are acquired simultaneously; these include spectral data in the regions 0.25–0.6 μ, 0.6 to 5 μ, and 5 to 15 μ, and radiometric data in the regions 0.25 to 0.6 μ and 0.6 to 15 μ. Calibration techniques are described.

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Ratio-recording spectroradiometer

Hammond III, H.K., Holford, W.L., Kuder, M.L. · National Institute of Standards and Technology (NIST)

A ratio-recording spectroradiometer has been constructed primarily for determining the relative spectral irradiance from fluorescent lamps in the visible spectrum. Radiant flux from a test source and a comparison source is transmitted or reflected by separate diffusers. Their radiance from each diffuser is sampled alternately of the order of 100 times a second by a double prism monochromator with cam-linearized wavelength drive from 360 to 760 mµ. A 14-stage multiplier phototube with S- 20 response is used with an electronic gate and integrator circuits to compare the spectral irradiances from the two sources. When the phototube outputs are unequal, a servo unit adjusts apertures in each beam to equalize them. The measured parameter is the amount of adjustment required for equalization at each wavelength. The apertures are adjusted by a cam coupled to a pen which records the ratio on a three-cycle logarithmic strip chart. The instrument requires about 8 minutes to record the spectrum at 10 mµ per inch. An expanded scale of 1 mµ per inch is used for evaluating the energy in the spectral lines. The speed of wavelength scan may be made inversely proportional to the unbalance signal, if desired, to provide ample time to record spectral lines accurately. Symmetry of beam treatment is demonstrated by interchanging test and comparison sources and recording the inverse ratio.

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Wide angle spectroradiometer

R S Adhav · Journal of Scientific Instruments · 1963

A spectroradiometer for the measurement of spectral irradiance (in μw cm-2 (3 nm)-1) in the wavelength range 420 nm to 1100 nm is described. It has an entrant system, consisting of an integrating sphere with a conical baffle inside, for obtaining good cosine response. A 250 mm Bausch and Lomb grating monochromator is used as a dispersing unit and narrow band energies are detected by an R.C.A. photomultiplier having S-1 type spectral response. The output is fed to a differential amplifier and the unbalanced anode current is calibrated for different wavelengths. The sensitivity at the wavelength of maximum response (740 nm) is 17.7 μw cm-2 (3 nm)-1 μA-1.

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ARM: Rotating Shadowband Spectroradiometer

Scott Stierle, Joseph Michalsky · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 2003

Rotating Shadowband Spectroradiometer

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Balloonborne Far-Ir Spectroradiometer

G. Serra, G. Bellaiche, P. Encrenaz et al. · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1987

Pronaos, a two metre balloonborne submillimetre telescope, supported by CNES and designed by a French collaboration between CNRS institutes and CNES-CST is presented. This project is now approved and in a preliminary definition phase B. It is intended to provide a facility for long duration flights (more than 20 hours) for photometry and spectroscopy in the spectral range 80 micrometres to 1.5 millimetre. Two focal plane instrumentations are considered : 1) a multiband photometre device using He3 cooled bolometres and He4 cooled filters. 2) a submillimetre heterodyne spectrometre. The two-metre Cassegrain telescope, with a lightweight primary mirror has an equivalent focal ratio F/10. The telescope is pointed (accuracy of 5&quot;rms) with a two stages stabilisation having a two axis sys-tem : 1) the azimuth orientation of the gondola provides from the decoupling with the balloon (ac-curacy of a few arc-minutes) and 2) an elevation/ cross-elevation gimbal.

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Moderate Resolution Imaging Spectroradiometer

St. Brusch, S. Lehner, J. Schulz-stellenfleth · 2013

The aim is to use Synthetic Aperture Radar (SAR) in synergy with optical data to analyse severe weather systems, e.g., Tropical Cyclones, North Atlantic Storms and Polar Lows. Radar reflectivity over the ocean depends on the roughness of the sea surface and thus mainly on the wind field. Additionally the backscatter of the radar signal is influenced by the size of hydrometeors, e.g. rain drops or snow in the atmosphere and their precipitation rate. The Medium Resolution Imaging Spectrometer (MERIS) instrument that is flying on board the ENVISAT satellite or the

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Resolution Imaging Spectroradiometer MODIS;

2015

September 2000–present have provided an unprec-This is an issue of fundamental importance to the study of global change. In response, the National Oceanic and Atmo-spheric Administration NOAA and NASA estab-lished an effort to reanalyze the CZCS record by utilizing advances in algorithms that are shared by modern remote sensing missions. In this paper we describe the methods and results of this effort, called the NOAA–NASA CZCS Reanalysis Effort NCR. Our methods involve the application of 1 recent al-gorithms to CZCS data to enhance quality and pro-vide consistency with the modern sensors OCTS, SeaWiFS, and MODIS and 2 blending techniques1 combining satellite data and the extensive in situ

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International Spectroradiometer Intercomparison 2026

Dp, Diego Pavanello · 2026

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Moderate-Resolution Imaging Spectroradiometer

Craig Daughtry B, Jeff Morisette C, Crystal Schaaf D et al. · 2002

www.elsevier.com/locate/rse Validating MODIS land surface reflectance and albedo products: methods and preliminary results

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Staring infrared imaging spectroradiometer

James B. McGlynn, Garth L. Gerber, David Perry et al. · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1995

A design approach for developing a staring-dispersive infrared imaging spectroradiometer utilizing a fiber-optic image formatter to simultaneously capture, at rates greater then 100 Hz, 256 high-resolution spectral images of a 2D scene is described. Detailed performance analyses confirm that the spectral radiance within the image scene can be measured to high absolute accuracy. The proposed low-risk prototype, based on commercial off-the-shelf components to minimize the development risk, can be cost-effectively upgraded to a final field instrument through replaceable optical, calibration, and detector modules. Producibility of the design, as described by mechanical layouts and manufacturing drawings of the optical, fiber-optic, and dispersive elements, has been confirmed by independent component manufacturers. The rugged design is sufficiently compact for use in high-performance military aircraft, and can be applied to numerous civilian applications such as environmental cleanup, mineral surveys, vegetation monitoring, and combustion analysis.

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Autonomous three channel spectroradiometer

Carolyn W. Chang, L. Char, Joseph Wong et al. · 2012

Above water reflectance measurements are usually made laboriously with handheld sensors. In recent years, autonomous robotic systems or fixed spectro-radiometers are used. In this work, we used off-the shelf optical systems with standard netbooks to make autonomous measurements of water reflectance. The optical systems are calibrated radiometrically and spectrally.

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Advanced Solidstate Array Spectroradiometer

Irons, J., Huegel, F. G. · NASA STI Repository (National Aeronautics and Space Administration)

During the Summer of 1987, the Advanced Solidstate Array Spectroradiometer (ASAS) was installed and flown on the NASA Ames C-130 in support of the First International Field Experiment (FIFE) missions. The study site was over the grassland areas of the Konza Prairie in Kansas. The data collected with ASAS during these flights has been used to produce the first nearly simultaneous multiangular/multispectral images of selected terrestrial study sites. This data will be valuable in the study of surface bidirectional reflectance and albedo. The data will also be useful for the development of data analysis algorithms for future spaceborne instruments such as the Goddard MODIS-T and JPL's HIRIS. The flight data acquired is further analyzed.

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Shortwave Spectroradiometer (SWS) Handbook

Peter Pilewskie, J. Pommier · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 2006

The Shortwave Spectroradiometer (SWS), measures the absolute visible and near infrared spectralradiance (units of watts per meter square per nanometer per steradian) of the zenith directly above the instrument. The SWS is a moderate resolution sensor comprised of two Zeiss spectrometers (MMS 1 NIR enhanced and NIR-PGS 2.2) for visible and near-infrared detection in the wavelength range 350 – 2170 nm. The sampling frequency is 1 Hz. The spectral resolution is 8 nm for the MMS 1 NIR and 12 nm for the NIR-PGS 2.2. The light collector is a narrow field of view (1.4°) collimator at the front end of a high-grade custom-made fiber optic bundle. The SWS does daily daytime measurements. The SWS is located in a darkroom, constructed by Southern Great Plains (SGP) site personnel within the optical trailer, to permit calibrations to be conducted without the necessity of moving the instrument to a different location. Calibrations are performed at regularly scheduled times using the ARM 12” integrating sphere.

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LOW COST DIGITAL SPECTRORADIOMETER*

Wolfgang F. Kaufmann, K. Hartmann · Photochemistry and Photobiology · 1989

Abstract— A self‐made low cost digitized single beam spectroradiometer is described. It is designed and calibrated to measure spectral radiant intensities in one nanometer steps for bandwidths between 1 and 20 nm within the wavelength range 200–1100 nm. The voltage output of the photoelectric detector‐system is proportional to the logarithm of the received irradiance and so constant signal resolution is gained over more than three orders of radiant intensities. Raw data recording and processing is done by a common 8 bit microcomputer, programmed in Microsoft Basic. Scanned emission spectra of a far‐red fluorescent lamp and a long arc xenon discharge lamp are presented and compared to manufacturer's data. In addition, the emission spectrum of a blue fluorescent tube has been determined to test for photometric aptitude. In this context the integral irradiances have been both measured and calculated for three radiometric sensors of defined spectral responsivities, indicating reliability of the instrumentation.

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