Objectives are the lenses that magnify the specimen being viewed under the microscope. Each objective has a different magnification, and the nosepiece allows the user to quickly switch between different objectives without having to manually adjust the focus.

The other function of the revolving nose piece is to center the objectives over the optical axis of the microscope.

This is important because it ensures that the light from the illuminator is focused properly on the specimen and that the image is sharp. The nosepiece is typically aligned with the optical axis of the microscope during the manufacturing process, but it can also be adjusted by the user if necessary.

Additional functions:

* The revolving nose piece can also be used to change the magnification of the microscope. By rotating the nose piece, the user can select the desired objective and then use the focusing knobs to adjust the focus of the image.

* The revolving nose piece can also be used to change the working distance of the microscope. The working distance is the distance between the front lens of the objective and the surface of the specimen. By rotating the nose piece, the user can select the objective with the desired working distance.