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Author Bará, S.; Escofet, J.
Title On lamps, walls, and eyes: The spectral radiance field and the evaluation of light pollution indoors Type Journal Article
Year 2018 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal (up) J of Quant Spect and Rad Trans
Volume 205 Issue Pages 267-277
Keywords Instrumentation; Light pollution; Artificial light at night; Light field; Radiance field; Radiometry; Photometry
Abstract Light plays a key role in the regulation of different physiological processes, through several visual and non-visual retinal phototransduction channels whose basic features are being unveiled by recent research. The growing body of evidence on the significance of these effects has sparked a renewed interest in the determination of the light field at the entrance pupil of the eye in indoor spaces. Since photic interactions are strongly wavelength-dependent, a significant effort is being devoted to assess the relative merits of the spectra of the different types of light sources available for use at home and in the workplace. The spectral content of the light reaching the observer eyes in indoor spaces, however, does not depend exclusively on the sources: it is partially modulated by the spectral reflectance of the walls and surrounding surfaces, through the multiple reflections of the light beams along all possible paths from the source to the observer. This modulation can modify significantly the non-visual photic inputs that would be produced by the lamps alone, and opens the way for controlling—to a certain extent—the subject's exposure to different regions of the optical spectrum. In this work we evaluate the expected magnitude of this effect and we show that, for factorizable sources, the spectral modulation can be conveniently described in terms of a set of effective filter-like functions that provide useful insights for lighting design and light pollution assessment. The radiance field also provides a suitable bridge between indoor and outdoor light pollution studies.
Address Área de Óptica, Departamento de Física Aplicada, Universidade de Santiago de Compostela, Santiago de Compostela, Galicia, Spain; salva.bara(at)usc.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language English Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 2163
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Author Horvath, H.
Title Basic optics, aerosol optics, and the role of scattering for sky radiance Type Journal Article
Year 2014 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal (up) Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 139 Issue Pages 3-12
Keywords Light extinction; Scattering function; Atmospheric radiance; Ground reflectivity; Color effects
Abstract The radiance of the night sky is determined by the available light and the scattering properties of the atmosphere (particles and gases). The scattering phase function of the aerosol has a strong dependence on the scattering angle, and depending on the viewing direction different parts of the atmosphere and the ground reflectivity give the most important contribution. The atmospheric radiance cannot be altered by optical instruments. On the other hand the light flux of a distant star increases with the size of the telescope, thus fainter stars become visible. Light extinction, scattering function, atmospheric radiance, ground reflectivity, color effects and others are discussed in detail and a simple theoretical treatment is given.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 176
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Author Cinzano, P.; Falchi, F.
Title Quantifying light pollution Type Journal Article
Year 2014 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal (up) Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 139 Issue Pages 13-20
Keywords Atmospheric effects; Astronomical site testing; Scattering; Light pollution; Radiative transfer; Night sky brightness; Environmental pollution; Atmospheric pollution Corresponding author contact information
Abstract In this paper we review new available indicators useful to quantify and monitor light pollution, defined as the alteration of the natural quantity of light in the night environment due to introduction of manmade light. With the introduction of recent radiative transfer methods for the computation of light pollution propagation, several new indicators become available. These indicators represent a primary step in light pollution quantification, beyond the bare evaluation of the night sky brightness, which is an observational effect integrated along the line of sight and thus lacking the three-dimensional information.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 177
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Author Luginbuhl, C.B.; Boley, P.A.; Davis, D.R.
Title The impact of light source spectral power distribution on sky glow Type Journal Article
Year 2014 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal (up) Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 139 Issue Pages 21-26
Keywords Light pollution; Sky glow; Blue-rich light sources; LED; light emitting diode; lighting
Abstract The effect of light source spectral power distribution on the visual brightness of anthropogenic sky glow is described. Under visual adaptation levels relevant to observing the night sky, namely with dark-adapted (scotopic) vision, blue-rich (“white”) sources produce a dramatically greater sky brightness than yellow-rich sources. High correlated color temperature LEDs and metal halide sources produce a visual brightness up to 8× brighter than low-pressure sodium and 3× brighter than high-pressure sodium when matched lumen-for-lumen and observed nearby. Though the sky brightness arising from blue-rich sources decreases more strongly with distance, the visual sky glow resulting from such sources remains significantly brighter than from yellow sources out to the limits of this study at 300 km.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 178
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Author Kolláth, Z.; Kránicz, B.
Title On the feasibility of inversion methods based on models of urban sky glow Type Journal Article
Year 2014 Publication Journal of Quantitative Spectroscopy and Radiative Transfer Abbreviated Journal (up) Journal of Quantitative Spectroscopy and Radiative Transfer
Volume 139 Issue Pages 27-34
Keywords Light pollution; Radiative transfer; Light scattering
Abstract Multi-wavelength imaging luminance photometry of sky glow provides a huge amount of information on light pollution. However, the understanding of the measured data involves the combination of different processes and data of radiation transfer, atmospheric physics and atmospheric constitution. State-of-the-art numerical radiation transfer models provide the possibility to define an inverse problem to obtain information on the emission intensity distribution of a city and perhaps the physical properties of the atmosphere. We provide numerical tests on the solvability and feasibility of such procedures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4073 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number IDA @ john @ Serial 179
Permanent link to this record