Field emission gun

A Field Emission Gun (FEG) is a specialized type of electron source used in electron microscopy and other applications that require high-resolution imaging or precise electron beams. It operates on the principle of field emission, which is the emission of electrons from a sharp tip (the emitter) when subjected to a strong electric field. ### Key Features of Field Emission Guns: 1. **Emitter Structure**: The emitter typically consists of a sharp metal tip made from materials like tungsten or carbon.