Light Transmission Calculation of Soda-Lime Glass

Russell Blume, Charles Drummond III


"Modeling and optimization of solar-control glasses"


J. Am. Ceram. Soc., vol 85, no. 5, May 2002, p 1070-1076


Abstract: Computer-assisted design of experiments based on the D-optimal design methodology and multiple linear regression analysis has been applied to the control and optimization of solar-control properties of a sulfate-fined soda-lime-silicate glass (72.7% SiO2, 14.2% Na2O, 10.0% CaO, 2.5% MgO, 0.6% Al2O3) which has been modified with Fe2O3 (0.0 to 0.8 wt%), NiO (0.0 to 0.15 wt%), CoO (0.0 to 0.15 wt%), V2O5 (0.0 to 0.225 wt%), TiO2 (0.0 to 1.5 wt%), SnO (0.0 to 3.0 wt%), ZnS (0.0 to 0.09 wt%), ZnO (0.0 to 2.0 wt.), CaF2 (0.0 to 2.0 wt%), and P2O5 (0.0 to 2.0 wt%) additions. The experimental design consisted of 64 initial glass compositions which were fired as 500 g batches under ambient conditions in platinum crucibles at 1500°C for 3 h. The samples were then measured for total solar transmittance in accordance with the specifications of ASTM E903-96 (weighted ordinate method) using a Cary-500 UV/vis/near-IR spectrophotometer equipped with an integrating sphere. CIE-LAB color and visible transmittance (illuminant-A) was measured in accordance with the specification of ASTM E308. The total metal content, calculated as of V2O5, CoO, NiO, Fe2O3, FeO, P2O5, TiO2, SnO, ZnO, F, and SO3, was measured for each glass sample. A modified Lambert-Beer absorption law was utilized to correlate the apparent optical density at 210 discrete wavelengths necessary for the calculation of solar and visible transmittances to the glass batch composition. The developed model was then validated and was shown to exhibit excellent agreement with the measured optical transmission data. Innovative solar-control glasses with exceptional performance characteristics have been realized in the current investigation by application of novel computer-assisted design and multiple correlation methodologies.

The publication contains all analyzed glass compositions and parts of the transmission data: the total solar transmission, the total visible transmission, and color coordinates a* and b*. However, the regression coefficients are not included in the paper. It is possible to create models from the published data.