Microscope Working Distance

Microscope working distance is the amount of distance required between the objective lens and the top of the object in order for the sample to appear in focus. This rule applies to both biological microscopes and stereo microscopes.

Typically the larger the magnification of a high power objective lens, or stereo microscope auxiliary objective lens, the shorter the working distance. As magnification increases, working distance decreases. This sometimes necessitates the use of a long working distance objective lens. Long working distance (LWD) objective lenses were created to allow greater working distance while using higher magnification.

High power objective lenses often have the working distance noted on the microscope objective, as shown above.