The EMS Dimpler D500i is a precision electro-mechanical metallographic lapping instrument specifically designed for the mechanical pre-thinning of TEM (Transmission Electron Microscopy) specimens. It automates the dimpling technique, allowing 3 mm discs to be routinely and repeatably dimpled to thicknesses less than 10 microns. This process significantly reduces the subsequent ion milling time required to achieve electron transparency in TEM/STEM samples. The D500i features a non-contact Z sensor that continuously monitors dimpling levels and precisely halts the process at preset specimen thicknesses, offering an accuracy of ±1µm. It can process a wide array of materials, including germanium, carbides, silicon, gallium arsenide, carbon, aluminum alloys, sapphire, glasses, oxides, borides, silicides, and multi-phase materials. The automated features and precise control make it an indispensable tool for preparing high-quality specimens with a broader, near electron-transparent area.