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Re: Diffusing Teflon Layer

Forum: Processes Involving Optical Photons
Re: Diffusing Teflon Layer (Joost Veenkamp)
Re: Re: Diffusing Teflon Layer (Gumplinger Peter)
Date: 17 Apr, 2015
From: Joost Veenkamp <Joost Veenkamp>

 Dear Peter, Thank you for your reply. We've been trying to edit the G4OpBoundaryProcess.cc as you suggested. This does indeed introduce a diffusive property to the transmission, but with a relatively small probability. In order to acquire the diffuse transmittance resembling teflon, we obviously need to edit a bit more. However, we run into some problems trying to understand the code. ```A major point we have not managed to get our head around is the following: lines 489 to 501 seem to calculate whether a photon will be absorbed, reflected or transmitted. In the case of transmission, nothing happens to the photon i.e. the properties are unchanged. In the case of reflection, we enter the DielectricDielectric part of the code (line 926 onwards), where it is again calculated whether the photon will be reflected or transmitted with refraction based on the defined refraction indices. ``` Could you explain this structure, i.e. for what purpose is the first transmission defined? (lines 489-508) 489 G4double rand = G4UniformRand(); 490 if ( rand > theReflectivity ) { 491 if (rand > theReflectivity + theTransmittance) { 492 DoAbsorption(); 493 } else { 494 theStatus = Transmission; 495 NewMomentum = OldMomentum; 496 NewPolarization = OldPolarization; 497 } 498 } 499 else { 500 if ( theFinish == polishedfrontpainted ) { 501 DoReflection(); 502 } 503 else if ( theFinish == groundfrontpainted ) { 504 theStatus = LambertianReflection; 505 DoReflection(); 506 } 507 else { 508 DielectricDielectric(); 509 }

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