It depends on how detailed / high level modelling you need. For basic stuff, if you are willing to put in some work in designing the geometry of your optical elements, the free and open source ‘Optics Workbench’ for FreeCAD is quite good I think. Here is the GitHub link: GitHub - chbergmann/OpticsWorkbench
I found it very useful for making teaching demos such as shown in my latest YouTube video on beam splitters and the compound microscope here: Beam Splitters and the Advanced Filter Block (plus Microscope Length and Distance RMS/DIN Standards) - YouTube
but it is capable of a lot more.