The present architecture utilizes a Nonlinear Scattering Aperture Combiner that does not need to be optically multiplexed and then drives a Direct Compressor stage that produces a large temporal compression ratio to pump a Fast Compressor. This eliminates the need for a separate array of ATDMs, multiplexing optical elements, and, at the approximate 10.sup.7 joule energy output required for ICF, reduces the number of mechanical elements and gas interfaces from the order of 10.sup.3 to about 10. In addition, this provides a large reduction of the volume of the gas containment region. In order to accomplish this, a technique for transversely segmenting by color and/or polarization of the optical extraction beams of the Direct Compressor has been invented. In particular, it is directed towards the integration of the Direct Compressor with the Primary Laser Source and Fast Compressor. The embodiments describe how the high operating fluence are addressed in terms of avoiding optical damage and how to integrate the stages in fluid mechanical and optical aspects.

An apparatus and process for pumping laser media by an optical pump over a 10 nanosecond period and thereafter time compressing the energy into an extraction pulse and focusing onto a target with a final 1 nanosecond irradiation time are disclosed. The exciting pump pulses are directed into a lookthrough compression arrangement wherein they energize a stimulated scattering process in low pressure (about 1 atmosphere) gaseous media and impinge in an off axis backward geometry. The extraction pulse is formed and directed towards the target with the appropriate information (color, phase, desired irradiance pattern) impressed on it at relatively low energy by manipulation with conventional, solid material optical elements. Once formed, it traverses the gaseous media, is amplified, and proceeds through a vacuum transition section and onto the target. After the injection of the extraction pulse into the lookthrough compression arrangement, it is amplified in the gaseous media by conversion of the pump energy, coupled through the scattering process. The media and the pump and extraction pulses are tailored to give high energy gain to the input optical pulse, high output fluence, good beam quality (high fidelity amplification to the desired temporal and spatial shape), and time compression. Once injected into the entrance to the first section by the material elements, the extraction pulse proceeds through shutter areas that separate different media regions and encounter no further solid material optical elements as it travels to the target. The focus on the target is impressed before amplification and time compression from the pump pulses and results in a very high brightness irradiance of the target. The desired spatial pattern of irradiance on the target is likewise formed with material elements and then imaged onto the target. Fluences some 2-3 orders of magnitude above those available under the conventional art may be thus obtained with an output brightness better by some six orders of magnitude.

In an inertial containment fusion (ICF) system which uses a KrF laser, it is beneficial to perform pulse compression of the laser output to produce a higher-power, higher-intensity laser pulse at the target. Such pulse compression involves counter-propagating laser pump and seed beams. A short-pulse seed beam is amplified as energy is extracted from a long-pulse pump beam. Because such energy extraction is invariably incomplete, a fraction of the pump energy will exit the compression cell in the same direction as the optics used to create the seed beam. The invention involves a gas consisting of a noble gas such as neon or argon which may be excited by an electron beam to enhance absorption. By proper choice of gas, cell length, electron-beam excitation, and time delay, the residual pump beam may be absorbed almost entirely with less than 0.01% transmitted laser energy through the invention.

A single-photon Raman optical frequency comb source is provided, including: a light source assembly, a filtering mechanism, at least three electro-optical modulators, a wavelength division multiplexer and a single photon generating mechanism. The light source assembly is configured to generate a Raman scattering light. The filtering mechanism is configured to pass a light having a specific wavelength, to filter the Raman scattering light and obtain at least three Raman scattering spectral lines. Each electro-optical modulator is configured to modulate a frequency of one of the Raman scattering spectrum lines in one-to-one correspondence, so as to cause a frequency shift of the Raman scattering spectrum line. The wavelength division multiplexer is configured to multiplex all modulated Raman scattering spectral lines and output a Raman optical frequency comb. The single photon generating mechanism is configured to adjust the Raman optical frequency comb to obtain a single-photon Raman optical frequency comb.

A single-photon Raman optical frequency comb source is provided, including: a light source assembly, a filtering mechanism, at least three electro-optical modulators, a wavelength division multiplexer and a single photon generating mechanism. The light source assembly is configured to generate a Raman scattering light. The filtering mechanism is configured to pass a light having a specific wavelength, to filter the Raman scattering light and obtain at least three Raman scattering spectral lines. Each electro-optical modulator is configured to modulate a frequency of one of the Raman scattering spectrum lines in one-to-one correspondence, so as to cause a frequency shift of the Raman scattering spectrum line. The wavelength division multiplexer is configured to multiplex all modulated Raman scattering spectral lines and output a Raman optical frequency comb. The single photon generating mechanism is configured to adjust the Raman optical frequency comb to obtain a single-photon Raman optical frequency comb.