I am modeling an infinite conjugate microscope system using off-the-shelf designs from Thorlabs.

1. Microscope objective: TL2X-SAP - 2X Super Apochromatic Microscope Objective, 0.1 NA
2. Tube Lens 200mm: TTL200-A - Tube Lens, f = 200 mm, ARC: 350 - 700 nm

Individually the objective lens and tube lens designs works as expected. However, when they are put together, the image quality is far from nominal (1000 waves OPD).

I am unsure if it has got to do something with using multiple black box design files in a single zemax file or if there’s something fundamentally wrong with the combined design itself.

I have attached the zemax file with the combined microscope objective + tube lens and also the individual zemax BB files.

Any insight into what is causing the image quality to degrade by ≥ 1000 waves from nominal OPD is appreciated.

Thanks.