A device for forming an immersion film between a front lens of a microscope objective and a preparation on an inverted microscope. The device includes a protection device for preventing fluid leakage from the immersion film region, and an apparatus for supplying the immersion fluid (auto-immersion) to the immersion film region. The protection device is arranged statically in the main part of the microscope stand and the means for supplying immersion fluid to the immersion film region is connected to the protection device by means of an Aquastop system.