A preferred embodiment is a system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 to 10 mJ or greater for integrated outputs...http://www.google.com/patents/US7852899?utm_source=gb-gplus-sharePatent US7852899 - Timing control for two-chamber gas discharge laser systemAdvanced Patent SearchPublication numberUS7852899