Calculating spectral irradiance indoors

The spectral composition of the light that reaches any indoor work plane depends on the characteristics of the light sources and the spectral reflectances of the surrounding surfaces due to the multiple reflections experienced by the light rays along their paths from the source to the observation po...

Descripción completa

Detalles Bibliográficos
Autores: Bará Viñas, Salvador, Escofet Soteras, Jaume|||0000-0002-1775-4779
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/90107
Acceso en línea:https://hdl.handle.net/2117/90107
https://dx.doi.org/10.1177/1477153516667643
Access Level:acceso abierto
Palabra clave:Spectral irradiance
Light
Reflection (Optics)
Spectral Irradiance
Spectral Radiance
Effective Inverse Surface Function
Irradiació
Llum
Reflexió (Òptica)
Àrees temàtiques de la UPC::Ciències de la visió::Òptica física::Llum
Descripción
Sumario:The spectral composition of the light that reaches any indoor work plane depends on the characteristics of the light sources and the spectral reflectances of the surrounding surfaces due to the multiple reflections experienced by the light rays along their paths from the source to the observation point. We show that in indoor spaces, the source and surface radiances must obey a definite self-consistent relationship derived from the fact that each illuminated surface point acts as a secondary source of light. It is then established that the spectral irradiance on any plane is linearly dependent on the spectral radiance of the light source. The explicit integral form of this relationship provides a theoretical framework for a quantitative description of the surface effects. Additionally, under very general assump-tions, we show that the spectral irradiance can be computed from the spectral flux of the source through a simple multiplication by a wavelength-dependent function. This function, with units of inverse surface (1/m2), provides a convenient way for evaluating the effects that arbitrary changes in the source spectrum will produce on the spectral irradiance at the indoor point under study.