Abstract: A spark gap switch having a mid-plane or triggering electrode is brought o a conductive state using a photoconductive switch or other suitable switch, closed by a laser pulse on other pulsed light source. The photoconductive switch is connected between one of the primary electrodes and the mid-plane electrode and brings the potential of the mid-plane electrode to the same potential as the primary electrode when the photoconductive switch is closed. The use of the photoconductive switch permits shorter closing times and eliminates the need for high voltage auxiliary triggering circuits. Plural photoconductive switches, which are triggered in a precise predetermined sequence, improve the operation of Marx generators and other multi-spark gap switch applications.

Abstract: High power optically activated switches of the semiconductor type utilizing broadbanded flashlamp as the source of light for rendering the semiconductor conductive and thus close the switch. In order that the conductivity of the semiconductor when in the "on" state be uniform over the load current carrying cross-section thereof, the semiconductor is treated to produce a tapered density of trapping or re-combination centers therein, with the density being a maximum at the semiconductor surface which faces the flashlamp. Several novel configurations of these switches are shown, including reflectors for concentrating the flashlamp output on the semiconductor, and a plurality of semiconductor switches all activated by a single light source, as well as liquid cooled semiconductors.

Abstract: The invention concerns an EM Launcher wherein each projectile has an insuor which, when subjected to a breakdown voltage, allows current conduction through the EM rails and the projectile for acceleration thereof. The insulator thus provides a disposable switch for a rapid fire EM launcher, negating the necessity of electrical (inductor circuit) charging or mechanical (breech) recycling.A key element in the invention is the replacing of a repetitively operated external switch with a plurality of single-shot, disposable switches. Better performance can be obtained from a single-shot switch (i.e., lower inductance, lower on-state voltage drop) because the compromises required of a repetitive switch to enable it to recover its voltage holdoff are not necessary.