Gun laws in the Czech Republic in their war for religious freedom against professional well armed and trained Catholic Crusader invaders. The word used for one type of hand held firearm used by the Hussites, , later found its way through German and French into English as the term pistol. Name of a cannon used by the Hussites, the , gave rise to the English term, "howitzer". Under common law tradition, civilians could possess firearms except artillery and insidious weapons (e.g. firearms that had appearance of other objects, etc.). First gun control laws were enacted during the early 18th century and dealt with illegal use of
Field emission gun Field emission gun A field emission gun is a type of electron gun in which a sharply pointed Müller-type emitter is held at several kilovolts negative potential relative to a nearby electrode, so that there is sufficient potential gradient at the emitter surface to cause field electron emission. Emitters are either of cold-cathode type, usually made of single crystal tungsten sharpened to a tip radius of about 100 nm, or of the Schottky type, in which thermionic emission is enhanced by barrier lowering in the presence of a high electric field. Schottky emitters are made by coating a tungsten tip