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Working Distance

Definition: the distance between an objective and the object

German: Arbeitsabstand

Category: general optics

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The working distance of an objective is the distance between the objective and the object. That quantity is relevant in various situations; some examples:

In some cases, it may not be clear how exactly the mentioned distance is measured – for example, if some mechanical parts protude beyond the final lens. It should then be made clear what exactly is meant with the working distance.

Note that the working distance is not necessarily the same as the front focal distance. Even if the object is placed in a beam focus, that focus does not need to lie in the focal plane if the input light of the objective is not collimated.

See also: objectives
and other articles in the category general optics


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