Abstract: A pulsed laser system for generating light pulses or variable duration which includes a elongated member defining a laser discharge chamber having first and second ends, a gain medium disposed within the discharge chamber and means for stimulating pulse laser emission of the gain medium within the discharge chamber. A first reflector is positioned adjacent the first end of the discharge chamber, and a second reflector is positioned at a variable distance from the second end of the discharge chamber. By varying the distance of the second reflector from the second end of the discharge chamber, the duration of pulses emitting from the discharge chamber is varied.

Abstract: A resonant power circuit which supplies pulsed power to a load, such as a pulsed laser, from a d.c. supply by cyclically charging a capacitor. The capacitor is discharged through the load on closure of a switch which should then open to allow the capacitor to re-charge. Occasionally the switch fails to open and the circuit of the invention then develops and applies a reverse voltage to the switch to force it to become an open circuit.

Abstract: A metal vapor laser which can produce two or more discrete outputs from a single vacuum chamber. This is achieved by using two or more different materials and by confining each material to its own area so that the materials do not mix one with the other and optimum lasing performance can be obtained from each material. All the lasing areas have a common optical axis. The lasing outputs can be produced separately or mixed together as required.

Abstract: A lasing device which uses as a lasing media a material which lases in the gas or vapor phase, and in which the discharge chamber includes a porous element which absorbs the lasing material when it condenses into the liquid or solid phase. The porous element, which can be a porous ceramic material, retains the liquid media and does not allow it to run along the discharge tube if this tube is moved or tilted. The laser is thus able to operate when being moved or tilted.

Abstract: A condenser including a condenser chamber having an extension portion extending through the base of a refrigerant storage vessel. The length of the conduction path along this portion is variable. This may be performed by partial retraction of the extension from the vessel, or by inclusion of one or more insulating shields. Both extension and shield may be threaded. The vessel may be of thin stainless steel or compliant solid insulating material, allowing fine adjustment of the conductive path length by tightening of the shield against the base of the vessel. The internal surface of the chamber may be undulated, in particular by threading, to promote turbulent flow and mixing within the chamber. The extension may be recessed and joined to a filling tube, to facilitate initial cool down. The complete condenser is encased by expanded polyurethane foam inside a box.