SOLAR TRANSMITTANCE MEASUREMENTS USING AN INTEGRATING SPHERE WITH BROAD AREA IRRADIATION

This paper examines the broad area irradiation method for measuring so lar transmittance of advanced glazing materials. It shows that the app arent transmittance measured by this method is the product of the true transmittance, and two other factors related to the reflectance of th e sample. Not accounting for these other factors may lead to errors. M ethods for reducing and correcting these errors are discussed and meas urements are presented that illustrate these errors. It is shown that the broad area irradiation technique can be used with appropriate corr ections to accurately measure transmittance.