Hi Joerg

The apparence of the beam won't change with a coordinate break as the POP beam is defined on an array that is centered and perpendicular to the chief ray. The coordinate break has no effect on that. However you will see the effect in the POP ribbon in the coupling as the receiving fiber is positioned differently:

- Coordinate break 6: Decenter Y = 0

- Coordinate break 6: Decenter Y = 0.005

Let us know if it helps.

You can also use the Decenter X and Y of the Fiber Data tab in POP.

Sandrine

Hello, 

I was dealing with the same issue as the OP in this topic. Nevertheless, in the latest Zemax version POP seems to also ignore coordinate breaks w.r.t. the coupling efficiency change.. 

For example, I am modeling fiber coupling from an imported source. I clearly see changes in the coupling efficiency if I set the “Decenter” parameter in the POP window. However, if I place the a coordinate break with the same decenter before the image, the efficiency value doesn’t change at all. So basically what @Sandrine Auriol showed above is not happening to me. I guess this could be a bug in the latest version or am I missing something?

I do not necessarily need to use the coordinate break but I would like to set the position of the fiber as variable w.r.t. the optimization. Coordinate breaks seemed like an easy way to do so but since this does not seem to work, is there any alternative option?

Thank you in advance.

Marek