Abstract: This detonator includes a cylindrical anvil of dielectric material bearing on one face an area of electrical contact and on the other a fusible bridge of which one end is connected to the area of electrical contact via a plugged conducting hole and of which the other end is connected to an annular conducting area around the edge of the anvil. A cylindrical hollow plug is connected to the anvil by a flanged ring soldered to the plug and to the annular conducting area of the anvil. Around this plug is fitted a cylindrical flexible contact part. A closing cylinder is soldered to the plug. Inside the plug are fitted a disk of plastic material, a barrel, and an explosive charge in a case. The assembly is closed by a cap laser welded to the closing cylinder. The invention is applicable to hermetic detonator structures for initiation in particular of warheads, propellors of rockets, missiles or other guided projectiles, or of gas generators.