long working distance objective (LWD)

An objective designed with a long focal distance to enable deep imaging or to allow for more space around the sample.

Related MicroscopyU Article

Objective Working Distance

Microscope objectives are generally designed with a short free working distance, which is defined as the distance from the front lens element of the objective to the closest surface of the coverslip when the specimen is in sharp focus. In the case of objectives designed to be used without coverslips, the working distance is determined by the linear measurement of the objective front lens to the specimen surface.