the .pob document used.

Hello,

I loaded your zmx file and the pob. The zmx file has only a Source Diode and a Detector Rectangle -- no pob.  I suggest you post the current design with the problem, but save it first as a zar file and attach that. With a zar, the pob will be included and also the window setup in the design file so we can reproduce exactly what you see.

Kind regards,

David

One thing I might note without looking: If the Detector Rectangle is placed such that rays hit it from both front and back on their way to and fro the corner reflector, then you could double count. You can avoid that by placing the detector so it is struck by the refected rays only, or you can set FrontOnly = 1 in the detector parameters and use tilts to orient the detector to face the rays you wish to count.

I note also that in your zmx file the wavelength is set to 1550 um. I think you mean to use 1.55 um. The wavelength is in um, not nm.

Thank you very much，David. As you said, set FrontOnly=1 and use tilts, the problem was solved immediately.

By the way, I uploaded the wrong file yesterday, because of too many versions :(. Anyway, thank you for the tipps of .zar.

All the best,

yingjie