The large optical surfaces of their eyes were divided into hundreds of small facets.

The entrance pupil is usually a virtual image: it lies behind the first optical surface of the system.

Lenses are classified by the curvature of the two optical surfaces.

Warm cabin air was diverted to prevent condensation on optical surfaces.

These segments will then be arranged to form a single optical surface.

Transition from the optical surface to the lens outside diameter requires a minimum radius value of 0.3 mm.

For example, an important characteristic of a lens is the form of the optical surface.

Additionally, when working with tactile measurement systems there is always a risk that the optical surface might be scratched.

In this case, only the cleanliness of the optical surface has to be monitored.

They are used with a monochromatic light to determine the flatness of other optical surfaces by interference.