TY - CPAPER KW - BSDF KW - buildings KW - energy efficiency KW - goniophotometry KW - reflection KW - scattering KW - transmittance AU - Lars Grobe AU - Stephen Wittkopf AU - Peter Apian-Bennewitz AU - Jacob Jonsson AU - Mike Rubin AB - The development of advanced materials for facades aims to achieve higher energy efficiency of buildings. Successful application of these materials depends on the availability of reliable characterization data. While data derived from integrated measurements of transmission and reflection is widely available, it does not allow to characterize the angular dependence of the performance of such materials. The Bidirectional Reflection-Transmission Distribution (BRTD) can be measured by commercially available Gonio-Photometers and, complimenting integrated transmittance and reflectance, allows the assessment of facade materials and thus supports both their development and application. Validation of the obtained data is crucial to back these measurements. Integration of validation procedures into the operation of a characterization laboratory allowing a well-defined approach to quality control is presented for a range of typical material and sample types: - consistency checks of measurement data - cross-checking of integrated material properties derived from BRTD data with integrating sphere measurements - round-robin comparison between laboratories using comparable devices The results of of these first measurements are discussed. Potential to further improve the availability of reliable angular resolved characterization data for the building sector is identified. BT - Proceedings SPIE 7725, Photonics for Solar Energy Systems III, 772510 CY - Brussels DA - 05/2010 DO - 10.1117/12.854011 N2 - The development of advanced materials for facades aims to achieve higher energy efficiency of buildings. Successful application of these materials depends on the availability of reliable characterization data. While data derived from integrated measurements of transmission and reflection is widely available, it does not allow to characterize the angular dependence of the performance of such materials. The Bidirectional Reflection-Transmission Distribution (BRTD) can be measured by commercially available Gonio-Photometers and, complimenting integrated transmittance and reflectance, allows the assessment of facade materials and thus supports both their development and application. Validation of the obtained data is crucial to back these measurements. Integration of validation procedures into the operation of a characterization laboratory allowing a well-defined approach to quality control is presented for a range of typical material and sample types: - consistency checks of measurement data - cross-checking of integrated material properties derived from BRTD data with integrating sphere measurements - round-robin comparison between laboratories using comparable devices The results of of these first measurements are discussed. Potential to further improve the availability of reliable angular resolved characterization data for the building sector is identified. PB - The International Society for Optical Engineering PP - Brussels PY - 2010 T2 - Proceedings SPIE 7725, Photonics for Solar Energy Systems III, 772510 TI - Experimental validation of bidirectional reflection and transmission distribution measurements of specular and scattering materials ER -