German to English Tech/Engineering

EStreu – in Rollladen contexts

The abbreviation is used in a table of product features for a rolling shutter.

Here they are referring to the blackout effectiveness of the shutter and the context is very short:

"Verdunklung: Verdunklungswirkung mittlere Innenbeleuchtungsstärke: EStreu, 1 Lx."

It apparently has something to do with Streuung – ? dispersion ? or ? scatter ? – and perhaps Entfernung – ? distance ? – but I cannot find the English equivalent abbreviation, partly because there are not many Internet references to the German abbreviation.

The term is discussed at this site, but only in German:

http://www.mh-hannover.de/einrichtungen/bpc/lehre/skript/pdf...

It also seems to make a difference whether the "Streu" part of the abbreviation part is superscript or a subscript. In my context, it appears to be a subscript.

At the above site, there is a somewhat complex formula for EStreu that doesn't help me much and cannot be reproduced here.


I tried searches for "Ddisp" and "Dscat" with no apparent success.

Any suggestions?

Thank you,

Dan