Abstract: Generation of impurity ions is prevented or reduced in a carbon ion generating device in which a laser-driven ion acceleration system is employed. A carbon ion generating device generates a carbonized region by irradiating a film made of an organic compound with a first laser beam, and generates carbon ions by irradiating at least a part of the carbonized region with a second laser beam.

Abstract: A plasma shutter forming apparatus for forming a plasma shutter used in a system configured to generate and accelerate radiations by irradiating a target with a laser pulse and generating a high-density plasma for blocking the laser pulse which is returned as a feedback light to upstream of the system without being absorbed by the high-density plasma, including a plasma shutter generating target, and a plasma shutter triggering laser irradiator, wherein the laser pulse from the plasma shutter triggering laser irradiator is directed to the plasma shutter generating target to generate the high-density plasma and form the plasma shutter, thereby blocking the laser pulse which is returned as the feedback light. Optics are prevented from becoming damaged by feedback light reflecting when generating the high-density plasma in a laser-driven radiation generating system and returning back to the upstream of the laser system.

Abstract: A high pressure discharge lamp has a sealing portion that is made of glass and a sealing metal piece. In a method of manufacturing the high pressure discharge lamp, the sealing metal piece is irradiated with laser beam whose pulse width is 1×10?9 seconds or less, so as to carry out a surface treatment of the sealing metal piece. The sealing metal piece may have a groove that is 120 to 600 nm in depth and 450 to 1,200 nm in width.

Abstract: A plasma shutter forming apparatus for forming a plasma shutter used in a system configured to generate and accelerate radiations by irradiating a target with a laser pulse and generating a high-density plasma for blocking the laser pulse which is returned as a feedback light to upstream of the system without being absorbed by the high-density plasma, including a plasma shutter generating target, and a plasma shutter triggering laser irradiator, wherein the laser pulse from the plasma shutter triggering laser irradiator is directed to the plasma shutter generating target to generate the high-density plasma and form the plasma shutter, thereby blocking the laser pulse which is returned as the feedback light. Optics are prevented from becoming damaged by feedback light reflecting when generating the high-density plasma in a laser-driven radiation generating system and returning back to the upstream of the laser system.

Abstract: A high pressure discharge lamp has a sealing portion that is made of glass and a sealing metal piece. In a method of manufacturing the high pressure discharge lamp, the sealing metal piece is irradiated with laser beam whose pulse width is 1×10?9 seconds or less, so as to carry out a surface treatment of the sealing metal piece. The sealing metal piece may have a groove that is 120 to 600 nm in depth and 450 to 1,200 nm in width.

Abstract: In the improved method for increasing the contrast of a high-intensity laser, signal light outputted from a laser oscillator, a preamplifier or the like is amplified by OPCPA which is excited by pump light having a short pulse width comparable to that of the signal light, thereby producing an extremely high contrast.

Abstract: In the improved method for increasing the contrast of a high-intensity laser, signal light outputted from a laser oscillator, a preamplifier or the like is amplified by OPCPA which is excited by pump light having a short pulse width comparable to that of the signal light, thereby producing an extremely high contrast.

Abstract: Conventionally, a laser beam is amplified by making a single pass through an amplifier but the laser beam emitted from the oscillator generally has low energy, so the energy stored in the amplifier cannot be fully extracted and only low laser output power and overall efficiency result. According to the method of the invention for amplifying a solid-state laser, the laser beam is passed through the amplifier multiple times and with spatial uniformity so as to achieve efficient extraction of the energy stored in the amplifier and the thermally induced distortion of the laser beam can be compensated by the single amplifier.

Abstract: Conventionally, a laser beam is amplified by making a single pass through an amplifier but the laser beam emitted from the oscillator generally has low energy, so the energy stored in the amplifier cannot be fully extracted and only low laser output power and overall efficiency result. According to the method of the invention for amplifying a solid-state laser, the laser beam is passed through the amplifier multiple times and with spatial uniformity so as to achieve efficient extraction of the energy stored in the amplifier and the thermally induced distortion of the laser beam can be compensated by the single amplifier.

Abstract: The efficiency of wavelength conversion of laser light can be improved by allowing incident laser light to pass through nonlinear optical crystals a multiple of times. In converting the wavelength of laser light to generate second- and higher harmonic waves, a returning mirror, a polarizer and nonlinear optical crystals are combined and the rotation of polarized light is utilized to allow the incident laser light to undergo multiple passes through the nonlinear optical crystals so that it can be converted in wavelength with higher efficiency.

Abstract: A passive eight-pass solid-state laser amplifier is constructed using a quarter-wave plate (11), a total reflection mirror (12), a polarization beam splitter (5), and a total reflection mirror (6) while input/output faces of a hexagonal zigzag slab solid-state laser medium (15) optically pumped are kept nearly perpendicular to pulsed laser light. Thermal birefringence takes place in the laser medium (15) optically pumped with good symmetry by flash lamps or LDs (9) and is compensated for by a quartz 90.degree. rotator (10). Linearly s-polarized laser light reflected by a polarization beam splitter (3) is output as pulsed laser output light (13) to the outside. Owing to this, saturation laser amplification can be achieved using output laser light from a pulsed laser oscillator of relatively low output, as source light.