Hello,

I’m currently dealing with a partially afocal system in Non-Sequential mode, where a pair of rod lenses focus light from a gaussian source onto a detector. I’ve been observing a series of lines that I cant explain. They appear after passing through a cylinder lens, and are not present in if I put a detector next to the source

I initially thought it was a sampling issue, but more rays simply made these structures more apparent. I’ve tested two ways of making the cylinder lenses (toroidal lens & cylinder object), no difference. I’ve tested a second source type (two-angle) and got the same result. I’ve also tested removing all elements, and the structure only appears with the cylindrical lenses.

Any idea what could be causing this?