The dimple grinder is used in the mechanical thinning of TEM-samples. This method reduces the needed time of following preparation methods greatly.

The dimpler creates a grinding recess in the central part of the sample, which has a remaining adjustable thickness of up to a few µm. The dimple wheels are made of copper, bronze or stainless stell and they are used with a diamond or boron nitride paste.

A polishing step afterwards yields an extremely smooth and specular surfaces.

The accuracy of the recess is about 1-2µm. A stereomicroscope allows for accurate alignment of the sample in the grinder.