Preionizationd device, in particular for x-ray preionization in discharge-pumped gas lasers, in particular excimer lasers

US5138627A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Dirk Friede · Goldbach, DE
• Willi Bette · Erlangen, DE

Key dates

• Filing date: Oct 22, 1990
• Grant date: Aug 11, 1992
• Expiry date: Oct 22, 2010

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/09713
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A preinoization device, in particular for X-ray preionization in discharge-pumped gas lasers, especially excimer lasers, is connected to a pulse generating network of an excitation circuit for gas lasers. A high voltage pulse transformer has a primary winding connected between a storage capacitor and a high-voltage switch in the pulse generating network. The pulse transformer emits preionizing pulses on the secondary side that lead to the firing of the laser glow discharge for a preionizing device, in particular an X-ray tube. The pulse transformer is constructed for this purpose as a saturable magnetic inductor with at least one secondary winding. If the high voltage switch is closed, when the pulse transformer is unsaturated its primary winding has its maximum inductance, so that there will be a secondary side voltage pulse at this time because of the law of induction. After a pre-set delay or retardation time of 50-100 ns, for example, the core will be saturated, the inductance of the primary winding will drop rapidly, and the full current will flow within the inversion circuit, so that the full high voltage builds up on the laser electrodes in order to fire the glow discharge.