Abstract: An EUV radiation source that employs a low energy laser pre-pulse and a high energy laser main pulse. The pre-pulse generates a weak plasma in the target area that improves laser absorption of the main laser pulse to improve EUV radiation emissions. High energy ion flux is reduced by collisions in the localized target vapor cloud generated by the pre-pulse. Also, the low energy pre-pulse arrives at the target area 20–200 ns before the main pulse for maximum output intensity. The timing between the pre-pulse and the main pulse can be reduced below 160 ns to provide a lower intensity of the EUV radiation. In one embodiment, the pre-pulse is split from the main pulse by a suitable beam splitter having the proper beam intensity ratio, and the main pulse is delayed to arrive at the target area after the pre-pulse.

Abstract: An EUV radiation source (40) that includes a nozzle (42) positioned a far enough distance away from a target region (50) so that EUV radiation (56) generated at the target region (50) by a laser beam (54) impinging a target stream (46) emitted from the nozzle (42) is not significantly absorbed by target vapor proximate the nozzle (42). Also, the EUV radiation (56) does not significantly erode the nozzle (42) and contaminate source optics (34). In one embodiment, the nozzle (42) is more than 10 cm away from the target region (50).

Abstract: An EUV radiation source (40) that includes a nozzle (42) positioned a far enough distance away from a target region (50) so that EUV radiation (56) generated at the target region (50) by a laser beam (54) impinging a target stream (46) emitted from the nozzle (42) is not significantly absorbed by target vapor proximate the nozzle (42). Also, the EUV radiation (56) does not significantly erode the nozzle (42) and contaminate source optics (34). In one embodiment, the nozzle (42) is more than 10 cm away from the target region (50).

Abstract: A singlet-delta oxygen generator 10 comprises a chamber 14 in which a gas stream 22 of singlet-delta oxygen, O.sub.2 (.sup.1 .DELTA.), is generated; a water vapor trap 40 to remove water vapor from the gas stream, and a liquid separator 60 downstream of the water vapor trap to separate liquid from the gas stream subsequent to removal of the water vapor. The water vapor trap comprises a liquid droplet dispersing device 42 which forms a droplet field 44 of cold liquid droplets in the chamber. The cold liquid droplets interact with and condense water vapor in the gas stream. The cold liquid is preferably hydrogen peroxide. The liquid separator comprises a baffle 62 arrangement which forms a tortuous flow path for the gas stream. Liquid in the gas stream is unable to traverse the baffles and is separated from the liquid, to produce an essentially dry gas stream for introduction into a gain generator 34 downstream of the singlet-delta oxygen generator.

Abstract: A singlet-delta oxygen generator suitable for use in a COIL-type chemical laser system is provided wherein the generator has a gaseous reactant distributor which includes (a) side, top and bottom walls to form a distribution chamber; (b) a thin distribution plate disposed vertically within one of the side walls adjacent to the falling droplet zone, the distribution plate having a plurality of holes to allow the passage of gaseous first reactant therethrough; (c) a plurality of gaseous first reactant inlet openings for allowing the influx of gaseous first reactant into the distribution chamber; and (d) a liquid drain disposed in the bottom wall. In a preferred embodiment of the invention, the gaseous reactant inlet openings are conduits which direct the influx of gaseous first reactant away from the distribution plate.

Abstract: A high energy chemical laser capable of being operated in an aircraft to interdict and destroy theater ballistic missiles is provided. A key to the chemical laser of the invention is the use of individual chemical lasers whose individual photon energy outputs can be combined into a single high-energy laser beam.

Abstract: A gain generator 10 for use in high-energy flowing gas lasers such as COIL devices comprises a chemical reactant mixing nozzle 12 disposed in a gain medium 16. The nozzle includes a plurality of blades 22 formed of a plastic material resistant to chemical attack at the operating temperature of the gain medium and non-catalytic to O.sub.2 (.sup.1 .DELTA.). A preferred material is polyetherimide. The gain medium includes octagonal shaped openings 50 for the optical mode of the laser beam.