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<TITLE>Re: [Radiance-general] Re: translucent panel ( trans material )</TITLE>
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<FONT SIZE="4"><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>Hi Coralie,<BR>
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I’m not familiar with Spectralon or if there are different varieties of spectralon, but all the hits of my quick search reveals a substance with high diffuse reflectance. And your measurements suggest high diffuse transmission. Is it possible that you are confusing Td with Rd? That would explain concerns regarding inconsistent transmission values for front and back.<BR>
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After talking with a materials guy, I now know that it is possible for a composite material to have different absorbance depending on direction of travel (ie if you have a silver coating on one side of glass, light from one side will pass through the glass twice while light from the other side may not pass through the material at all). So for me that is no longer a puzzle. <BR>
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Andy<BR>
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On 12/18/09 9:45 AM, "Coralie Cauwerts" <coralie.cauwerts@uclouvain.be> wrote:<BR>
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</SPAN></FONT></FONT><BLOCKQUOTE><FONT SIZE="4"><SPAN STYLE='font-size:11pt'><FONT FACE="Arial Narrow">Hi all, <BR>
<BR>
Thanks for your responses.<BR>
Values were measured with a spectrophotometer UV-VIS-NIR. The reference is a spectralon. I know that measurements are only indicative because some errors can occur when diffuse material is measured with this kind of method but I have no other source of information about the material.<BR>
In my model, only the “interior side” of the glass is visible.<BR>
Andrew, I agree with your correction, I saw my mistake yesterday …<BR>
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Coralie<BR>
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Coralie Cauwerts<BR>
Researcher<BR>
Université catholique de Louvain<BR>
Belgium<BR>
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