System and method for beam shaping laser coupled to optical cavity

Abstract

In one example, in accordance with the present invention, techniques are provided that generally relate to fusion energy generation. In particular, the present invention provides a system and method for generating fusion energy using a high intensity pulse or CW laser generation system, and related methods. More specifically, the present invention provides dynamic beam shaping of light sources for laser fusion.

Description

Technical Field

[0001] The present invention relates to a system and method for a beam shaping laser coupled to an optical cavity. Background Art

[0002] The present invention relates generally to fusion energy generation technology. In particular, the present invention provides a system and method for fusion energy using a high intensity pulsed laser generation system, and related methods. More specifically, the present invention provides dynamic beam shaping of light sources for laser fusion. By way of example only, the present invention can be applied to a variety of applications, including energy generation for power, spacecraft, travel, other vehicles for air, land and water, defense applications (e.g., satellites, aerospace, land and missile defense, submarines, ships), biotechnology, chemical, mechanical, electrical, and communications and / or data applications.

[0003] Since ancient times, humans have developed energy from natural materials such as wood, coal, oil and gas products. Unfortunately, burning wood and coal can lead to serious pollution problems, including the addition of unwanted carbon particles to the atmosphere. Oil and gas products have similar limitations and are the main cause of "global warming." Renewable energy sources such as nuclear power, wind power, hydroelectric power, and solar power hold great promise. However, these renewable energy sources also have other disadvantages. Wind power can only be generated when the wind blows. Solar power cannot be used when the sun goes down. Hydroelectric power is limited to areas with water. Nuclear power, while promising, has major problems with waste generation and unreliable and dangerous reactors. Another promising energy source is fusion energy.

[0004] Fusion energy is a way of generating energy when two atomic nuclei fuse, releasing a large amount of energy in the process. The fuel for fusion reactions (mainly hydrogen) is very abundant on Earth, and fusion reactions do not produce greenhouse gases or other harmful pollutants, so they are considered a potential clean and abundant energy source.

[0005] There are two main approaches to achieve fusion reactions: inertial confinement fusion (ICF) and magnetic confinement fusion (MCF).

[0006] Inertial confinement fusion (ICF) involves using high-energy lasers or particle beams to compress and heat a small mass of hydrogen fuel, causing it to fuse. The fuel is usually a mixture of two isotopes of hydrogen, deuterium and tritium. The fuel is contained in a small spherical capsule called a hohlraum, which is placed in the center of a chamber filled with a high-energy laser or particle beam. When the laser or particle beam is directed at the hohlraum, they create a uniform layer of X-rays that evenly heat and compress the fuel inside the hohlraum. This brings the fuel to the temperature and pressure conditions required for fusion to occur.

[0007] The main advantage of ICF is that it can produce fusion reactions with relatively small amounts of fuel and at relatively low cost. However, the process is still in the experimental stage and there are significant technical challenges to overcome before it can be considered a practical energy source.

[0008] Magnetic confinement fusion (MCF) involves the use of strong magnetic fields to contain and heat a plasma (a hot ionized gas) of hydrogen fuel, causing it to fuse. The most common form of MCF is called tokamak fusion, which uses a toroidal (donut-shaped) chamber to contain the plasma. The plasma is held in place in the center of the chamber by a strong magnetic field, which is created by passing an electric current through a set of coil windings surrounding the chamber. The plasma is heated by injecting energy into it with particle beams or electromagnetic waves.

[0009] The main advantage of MCF is that it has the potential to produce fusion reactions on a larger scale, making it more suitable for generating electricity. However, it is a more complex and expensive process than ICF, and there are still significant technical challenges to overcome before it can be considered a practical energy source.

[0010] Both ICF and MCF have made significant progress in recent years, with several experimental facilities around the world studying these technologies. However, achieving sustained fusion reactions with net energy production (meaning that the energy produced by the fusion reaction is greater than the energy required to initiate and sustain the reaction) remains a major technical challenge.

[0011] There are other approaches to explore fusion energy, such as magnetized target fusion and muon-catalyzed fusion. However, these approaches are still in the early stages of development. It is not yet clear whether fusion energy is viable as an energy source.

[0012] In summary, fusion energy has the potential to be a clean and abundant energy source, but significant technological challenges must be overcome before it can be considered a practical energy source. Summary of the invention

[0013] In one example, according to the present invention, techniques generally related to fusion energy generation are provided. In particular, the present invention provides a system and method for generating fusion energy using a high intensity pulsed or CW (continuous wave) laser generation system, and related methods. More specifically, the present invention provides dynamic beam shaping of light sources for laser fusion. By way of example only, the present invention can be applied to a variety of applications, including energy generation for electricity, spacecraft, travel, other vehicles for air, land and water, defense applications (e.g., satellites, aerospace, land and missile defense, submarines, ships), biotechnology, chemical, mechanical, electrical, and communications and / or data applications.

[0014] In one example, the present application provides a laser system, including a pulsed laser device (or laser device) configured to emit a laser beam. The system has a beam splitter device coupled to the pulsed laser device. The beam splitter is configured to receive the laser beam and divide the laser beam into N paths, where N is an integer from 2 to 1000. Each laser beam in each path is amplified from a first energy level to a second energy level, and each laser beam in each path matches a predetermined polarization phase. In one example, the system has a combiner device configured to receive the N laser beams and configured to spatially or temporarily combine the N laser beams into an amplified pulse. The system optionally has an auxiliary device (e.g., a filter device) coupled to the combiner device, and is configured to shape the amplified pulse from a first Gaussian profile to a second Gaussian profile. Alternatively, the combiner device can be configured as a filter device. The system has a Fabry-Perot cavity configured to receive the amplified pulse. The cavity has a first mirror device and a second mirror device, and a free space defined between the first mirror device and the second mirror device to form a pair of mirror devices, so that for M cycles of the amplified pulse propagating between the pair of mirror devices, the amplified pulse propagating from the pulse laser device increases in energy intensity from a first intensity to a second intensity to an Mth intensity, where M is greater than 1000 or 10000 cycles. In one example, the laser beam is a continuous wave, rather than a pulse.

[0015] In another example, the present application provides a laser system. The system has a pulsed laser device configured to emit a laser beam. The system has a beam splitter device coupled to the pulsed laser device, and is configured to receive the laser beam and split the laser beam into N paths, where N is an integer from 2 to 1000, etc. Each laser beam in each path is amplified from a first energy level to a second energy level, and each laser beam in each path is matched with a predetermined polarization phase. In one example, the system has a combiner device, which is configured to receive the N laser beams and is configured to spatially combine the N laser beams into an amplified pulse. The system has an auxiliary device coupled to the combiner device, and is configured to shape the amplified pulse from a first Gaussian profile to a second Gaussian profile. In one example, the system has a Fabry-Perot cavity configured to receive the amplified pulse. The cavity has a first mirror device and a second mirror device, and a free space defined between the first mirror device and the second mirror device to form a pair of mirror devices, so that for M cycles of the amplified pulse propagating between the pair of mirror devices, the amplified pulse propagating from the pulsed laser device increases in energy intensity from a first intensity to a second intensity, and then to an Mth intensity, where M is greater than 1000 or 10000 cycles, etc. In one example, the system has an optical mode filter that is spatially disposed within the region of the Fabry-Perot cavity and is configured to reflect parasitic optical modes from the Fabry-Perot cavity to maintain a fundamental latest mode or a lower harmonic optical mode. The first and second mirror devices are attached to a heat sink (e.g., a heat dissipation system) to maintain its temperature within a desired predetermined range.

[0016] According to the above embodiments, the present invention can achieve one or more of these benefits and / or advantages. In one example, the present invention provides a fusion energy system including a high-intensity pulse or CW laser system configured with a reactor in a compact manner and a space-efficient system, and related methods. In one example, the high-intensity pulse or CW laser system provides sufficient energy to ignite and maintain fusion energy within the reactor. In one example, the present invention provides the advantages of using the present high-intensity laser to generate fusion energy through effective size, weight and cost. These and other benefits and / or advantages can be achieved using the present device and related methods. More details of these benefits and / or advantages can be found in this specification, especially below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a simplified schematic diagram of a laser system coupled to a Fabry-Perot cavity according to an example of the present invention;

[0018] Figure 2A simplified schematic diagram of a fusion reactor equipped with a laser system and a Fabry-Perot cavity;

[0019] Figure 3 A more detailed schematic diagram of a laser system according to an example of the present invention;

[0020] Figure 4 A more detailed schematic diagram of a Fabry-Perot cavity with an optical mode filter according to an example of the present invention;

[0021] Figure 5 For an example according to the present invention Figure 3 A simplified schematic diagram of the error control process of the laser system;

[0022] Figure 6 For an example according to the present invention Figure 3 A simplified schematic diagram of the electro-optic modulator of the laser system;

[0023] Figure 7 A simplified schematic diagram showing dynamic laser beam control for mirror deformation according to an example of the present invention;

[0024] Figure 8 A simplified schematic diagram showing mode removal of parasitic optical modes using optical mode filters by reflection. DETAILED DESCRIPTION

[0025] By way of background, ever since laser-based fusion reactors for energy generation were conceived, there have been many challenges in designing lasers that can deliver sufficiently high power and uniform pulse profiles to effectively ignite the target fuel. 1 For example, the National Ignition Facility at Lawrence Livermore National Laboratory in Livermore, California, circumvents the problem of poor beam uniformity in laser systems by performing indirect fusion, aiming the laser at the walls of the reactor cavity, producing incoherent high-energy X-rays that more evenly irradiate the spherical fuel particles, but the system suffers from significant energy losses. 2 Direct inertial confinement laser fusion is more energy efficient but requires tighter tolerances on laser beam characteristics such as beam shape and uniformity of power, intensity, and phase matching when reaching the target fuel. 3 Therefore, it is desirable to manufacture TEM 00 A seed laser with a Gaussian profile and high emission power stability, and efficiently amplifies the beam to megawatt (MW) power while maintaining a uniform shape.

[0026] One approach that can amplify lasers to high average powers is to use a high-finesse external Fabry-Perot cavity, also known as an optically enhanced cavity (OEC), which is described in "Boron fuel configured in a cavity with a laser source for a fusion system" listed in U.S. Patent Application No. 18 / 172,885 filed on February 22, 2023, which is jointly owned and incorporated herein by reference in its entirety. The OEC injects CW or pulsed laser light into a high reflectivity laser cavity, typically in a 2 or 4 mirror bowtie orientation, where the laser light in the cavity temporally and spatially intersects with the next injected laser pulse, coherently combining and amplifying the pulses in the cavity at each round trip. When the seed pulse is successfully mode- and phase-matched with the pulse train in the cavity, the laser pulses from a single-watt seed laser source are amplified to megawatts of power, typically using the Pound-Drever-Hall method, with combined efficiencies as high as 85% reported to date. 5 Although the mirrors used are ideally highly reflective to produce 1x10 5 The high-finesse cavity has a finesse of orders of magnitude, but a small fraction of the power absorbed by the cavity mirrors can cause significant thermoelastic deformations of the mirrors. These deformations lead to scattering into degenerate higher-order TEM (transverse electromagnetic) modes, which greatly reduce the system's amplification efficiency and beam shape, and can lead to further deformation and wavefront distortion if not controlled. 11-15

[0027] Various solutions have been applied to high-finesse cavities to counteract mirror expansion and reduce the generation of these higher-order modes. Spatial filtering using masks and collimated laser pulses produces a uniform profile but results in large power losses. 16 Gravitational wave detector facilities such as the Laser Interferometer Gravitational-wave Observatory (LIGO), which produces up to 750kW of continuous-wave laser light in the arms of its Fabry-Perot Michelson interferometers, utilize ring heaters to extend the backside of their optics to compensate for thermal deformation of the cavity facets. 17 While heating is effective for maintaining high intracavity laser powers for long periods of time (on the order of hours for LIGO), this approach provides poor dynamic control over the optical shape and heating position, especially on small mirrors with diameters less than 1", due to the slow heat dissipation in ultrahigh vacuum systems. 17-20

[0028] We propose to use dynamic beam shaping to adjust the beam shape of the seed laser, rather than modifying the geometry of the mirrors. Dynamic beam shaping lasers take advantage of coherent beam combining, a technique that combines two N A technique in which individual laser pulses are amplified and then combined to produce a single high-power laser pulse.21-23 By coupling acousto-optic and electro-optic modulators (such as the AOM (acousto-optic modulator) and EOM (electro-optic modulator) used in this paper, respectively) into the beam path, the phase and amplitude of each individual pulse can be adjusted. The combination of these phase-controlled pulses can form various interference patterns and finely control the laser shape and focus. By coupling a dynamic beam-shaping seed laser to a high-fineness external cavity, it will be possible to: (1) adjust the beam shape and focus at MHz frequencies to match the changes in mirror shape after thermoelastic deformation in real time, and (2) finely control the phase and focus of the injected laser after each round trip to facilitate higher efficiency combination.

[0029] In one example, the system includes a dynamic beam shaping injection laser and a high finesse external Fabry-Perot cavity for amplification. For the dynamic beam shaping laser, a TEM 00 Nanosecond pulse width laser and master oscillator power amplifier (MOPA) with up to 1J per pulse. Coherent beam combining requires 2 N The researchers used a method called multi-pulse multiplication to correctly combine multiple laser pulses into a single amplified pulse. Furthermore, the combination efficiency barely changed when extended to up to 64 pulses. 22 The laser entering the OEC must be seeded at a 1MHz repetition rate to match the round trip distance of the cavity (300m). Therefore, the dynamic beam shaping laser must be seeded at 2 N The laser pulses are directed to the EOM to adjust the phase of each pulse. After amplification through the fiber, the pulses are interferometrically combined to produce a specific shape for coupling to the OEC.

[0030] For the high-finesse cavity, two-mirror and four-mirror butterfly designs will be explored, but only the two-mirror design will be discussed below. Each mirror in the cavity has a diameter of 40 cm, a thickness of 40 mm, and a radius of curvature of 150 m. The reflectivities of the concave and flat surfaces are 99.99999% and 0.1%, respectively, to achieve efficient injection of laser pulses while maintaining high finesse. The coating on the concave surface is manufactured using proprietary technology. The entire beamline will be placed in a high vacuum (approximately 1×10 -6 -1×10 -8 The concave mirror will be placed under a support to prevent absorption and scattering by molecules in the atmosphere. The initial injection laser will consist of Gaussian pulses because no deformation occurs on the mirror surface. As higher energy pulses pass through the cavity after each round trip, the concave mirror will deform in a parabolic shape starting from the center of the mirror, causing phase mismatch, laser defocusing, and the formation of degenerate higher-order TEM modes. An error feedback loop using the Pound-Drever-Hall method will be installed to adjust the mirror mounting position to maintain stable mode locking. 24，25The seed laser will be interferometrically modified to adjust the shape of the laser pulse to match the shape of the deformable mirror after each round trip to account for the mirror extension. This will prevent scattering into higher order modes and more efficient amplification. While the shape and focus of the seed laser will be adjusted to account for the mirror deformation, the intracavity pulse cannot be modified, resulting in some but significantly fewer higher order modes. To suppress this propagation, two D-shaped mirrors placed along the two transverse axes will be installed to reflect these higher order modes into the walls of the reactor. 4，6 Each mirror will be placed on a motorized mount so that only higher order modes intersect the knife-edge plane.

[0031] Through the combination of a dynamically pulse-shaped seed laser and an OEC amplifying cavity, it will be possible to tune the shape, focus, and phase of the injection laser at MHz frequencies. This dynamic shape control will lead to higher amplification efficiency and less losses from scattering effects, allowing us to achieve the MW laser power required to compress fusion fuel with higher wall plug efficiency.

[0032] Further details of the present systems and related methods can be found throughout this specification, and particularly below.

[0033] Figure 1 1 is a simplified schematic diagram of a laser system coupled to a Fabry-Perot cavity according to an example of the present invention. As shown in the figure, a laser system is provided. The laser system has a pulsed laser device configured to emit a laser beam. The pulsed laser device has a master oscillator configured with a power amplifier. The pulsed laser device emits a laser with a pulse width of nanoseconds, a frequency of MHz and a wavelength close to IR, such as those of IPG Optoelectronics, but may also be other wavelengths.

[0034] The system has a beam splitter device coupled to a pulsed laser device. The beam splitter is configured to receive a laser beam and split the laser beam into N independent paths. N is an integer from 2 to 1000, but can be larger in other applications. In one example, the beam splitter is a polarization beam splitter, such as a polarization beam splitter from Thorlabs, but other polarization beam splitters can also be used.

[0035] Each laser beam in each path is amplified from a first energy level to a second energy level. Each beam is amplified using an Ytterbium-doped fiber amplifier device, such as a Thorlabs Ytterbium-doped fiber amplifier device, although other Ytterbium-doped fiber amplifier devices may also be used.

[0036] Each laser beam in each path is phase matched to a predetermined polarization so that each amplitude is aligned with a reference point. Phase matching is performed using an electro-optic modulator, such as a fiber-coupled electro-optic modulator from Thorlabs, but other modulators can also be used.

[0037] As shown, the device has a combiner device configured to receive N laser beams and to spatially combine the N laser beams into an amplified pulse. The combiner device is also a polarization beam splitter, such as a Thorlabs polarization beam splitter, but other polarization beam splitters may also be used.

[0038] As shown, the device has a filter device coupled to a combiner device and is configured to shape the amplified pulse from a first Gaussian profile to a second Gaussian profile. The second Gaussian profile is substantially error-free. In one example, the filter device can be an auxiliary device, etc. In addition, the first Gaussian profile and the second Gaussian profile can be any similar or quasi-Gaussian profile, i.e., a slight variation of a Gaussian.

[0039] The pulse laser device is coupled to a Fabry-Perot cavity configured to receive an amplified pulse. The Fabry-Perot cavity has a first reflector device and a second reflector device, and a free space defined between the first reflector device and the second reflector device to form a pair of reflector devices. The pair of reflector devices are configured so that for M cycles of the amplified pulse propagating between the pair of reflector devices, the amplified pulse propagated from the pulse laser device increases in energy intensity from a first intensity to a second intensity and then to an Mth intensity. M is greater than 10,000 cycles, but can be less. The first reflector device and the second reflector device substrate are composed of silicon carbide.

[0040] Further details of optical enhancement cavities using Fabry-Perot cavities can be found in a patent application titled “Fast Ignition Fusion Systems and Methods,” listed in the names of Shuji Nakamura and Hiroaki Ohta under U.S. Serial No. 18 / 319,368, filed on May 17, 2023, commonly assigned, the entire contents of which are incorporated herein by reference.

[0041] As shown in the figure, the device also has a detection device coupled to a portion of one of the reflector devices, and the detection device is configured to measure the signal from the amplified pulse to detect the phase and shape of the amplified pulse. The detection device is a charge coupled device (CCD) camera coupled to a portion of one of the reflector devices. The detection device is configured to measure the signal from the amplified pulse to detect the phase and shape of the amplified pulse. The CCD camera includes a plurality of detectors configured to detect electromagnetic radiation signals from about 400nm to 2000nm. For example, a CCD camera of Princeton Instruments, but other CCD cameras may also be used.

[0042] The system also has a controller system coupled to the pulsed laser device and coupled to the detection device. The controller system is coupled to the pulsed laser device and the detection device so that a feedback signal is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device. In addition, the controller device adjusts the phase, shape and focus of the laser beam from the pulsed laser device to adjust the deformation of any pair of reflectors. In an alternative example, the system has a controller system coupled to the pulsed laser device and the detection device so that a feedback signal from the amplified pulse is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device to adjust the deformation of any pair of reflectors caused by the increase in energy intensity.

[0043] In one example, the controller system can be of any suitable type that can control the beam shape, phase, and other parameters of the laser, thereby being able to manipulate and optimize the output of the laser. In one example, the controller is equipped with specially customized control logic and algorithms for adjusting the beam shape, phase, and other parameters of the laser. These algorithms can be customized to meet specific requirements. In one example, the controller is connected to a set of beam shaping optical devices, which may include lenses, optical elements, spatial light modulators (SLMs), or other optical components designed to modify the profile and shape of the laser beam. In one example, for phase control, the controller is connected to a phase modulator that allows precise phase adjustment of the laser beam, such as a liquid crystal device or an electro-optical modulator. In one example, the controller receives feedback from various sensors and detectors, which may include photodiodes, wavefront sensors, interferometers, or cameras. These sensors provide information about the parameters of the laser, including intensity, polarization, phase, and beam profile. In one example, the controller operates in a closed-loop control system, constantly comparing the detected data with the desired parameters or set points. In one example, based on the feedback, the controller calculates and implements adjustments to the beam shaping optics and phase modulator to achieve desired beam characteristics including beam profile, divergence, focus, and phase distribution.

[0044] In one example, the controller includes a graphical user interface (GUI) or software application. The interface allows the user to input desired laser parameters and monitor the performance of the system. Of course, there may be other variations, modifications, and alternatives.

[0045] Figure 2The figure is a simplified schematic diagram of a fusion reactor equipped with a laser system and a Fabry-Perot cavity. As shown in the figure, the Fabry-Perot cavity is configured as a reactor device for a fusion reaction. The system has a distributor device, which is configured to inject a target into the reactor device so that the target device interacts with the amplified pulse to induce a fusion reaction.

[0046] Figure 3 A more detailed schematic diagram of a laser system according to an example of the present invention. As shown in the figure, the pulse laser device includes an oscillator device coupled to an electro-optic modulator configured to adjust the phase of the laser beam and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by the beam splitter device.

[0047] Figure 4 A more detailed schematic diagram of a Fabry-Perot cavity with an optical mode filter according to an example of the present invention. As shown in the figure, the Fabry-Perot cavity is configured to receive an amplified pulse and includes a first reflector device and a second reflector device, and a free space defined between the first reflector device and the second reflector device to form a pair of reflector devices, so that for M cycles of an amplified light beam propagating between the pair of reflector devices, the amplified pulse propagated from the pulse laser device increases in energy intensity from a first intensity to a second intensity, and then to an Mth intensity, where M is greater than 10,000 cycles. The first reflector device and the second reflector device are made of silicon carbide.

[0048] In addition, the cavity is configured with an optical mode filter, which is spatially arranged within the region of the Fabry-Perot cavity. In one example, the optical mode filter is configured to reflect the parasitic optical mode to the surface area of ​​the Fabry-Perot cavity to maintain the temperature of each reflector within a predetermined temperature range. In one example, the predetermined range can maintain the shape of each reflector device. In one example, the optical mode filter transfers energy from the parasitic optical mode to the wall of the Fabry-Perot cavity. In addition, the optical mode filter includes a knife-edge reflector configured to reflect electromagnetic radiation from the parasitic optical mode. Of course, there may be other variations, modifications and alternatives.

[0049] Figure 5 For an example according to the present invention Figure 3 A simplified schematic diagram of the error control process for a laser system. As shown in the figure, the master oscillator system is configured to generate nanosecond pulsed lasers. Figure 4The Fabry-Perot cavity described in is configured to receive and amplify laser pulses. The mirrors of the Fabry-Perot cavity are configured to allow a small portion of the amplified laser pulse to escape the cavity, where the laser pulse is detected by a CCD camera device configured to measure the phase and amplitude of the pulse. The signal generated from the CCD camera device is sent to a signal mixer that is designed to send electronic signals to two destinations: a master oscillator system and an electro-optic modulator for adjusting the phase of the amplified laser pulse. Along the path to the master oscillator system, the electronic signal passes through a low-pass filter device and is then sent to an oscilloscope to measure the signal. The measured signal is forwarded to the electro-optic modulator to adjust the phase of the amplified laser pulse to be injected into the Fabry-Perot cavity.

[0050] Figure 6 For an example according to the present invention Figure 3 A simplified schematic diagram of an electro-optic modulator of a laser system. As shown, the electro-optic modulator receives a laser beam and passes through an electro-optic modulator material, which is coupled to a voltage source. The voltage adjusts the phase of the laser beam to a desired phase relative to the other split beams. An example of this material can include potassium dideuterium phosphate crystals, etc.

[0051] Figure 7 A simplified schematic diagram of dynamic laser beam control for deformation of a reflector according to an example of the present invention is shown. An initial reflector shape having a predetermined curve is shown. A deformed reflector is also shown. The deformed reflector is subjected to an amplified laser pulse which causes thermal expansion of the reflector, resulting in deformation. The deformation is corrected in whole or in part by adjusting the phase, shape and / or focus of the laser beam. Thus, the feedback and correction techniques of the present invention are used to correct the deformation.

[0052] Figure 8 A simplified schematic diagram of multimode laser pulses generated by deformation of a reflector in a Fabry-Perot cavity and optical mode filtering according to an example of the present invention is shown. As shown in the figure, a parasitic optical mode is generated when a deformed mirror is reflected. The deformed reflector is subjected to an amplified laser pulse, which causes thermal expansion of the reflector, resulting in deformation. The parasitic optical mode intersects with an optical mode filter and is directed to the wall of the Fabry-Perot cavity. The optical mode filter includes a knife-edge mirror configured to reflect electromagnetic radiation from the parasitic optical mode.

[0053] Further embodiments of the invention can be found throughout the description, particularly in the following.

[0054] In one example, the present invention provides a laser system including a pulsed laser device configured to emit a laser beam. The system has a beam splitter device coupled to the pulsed laser device. The beam splitter is configured to receive the laser beam and split the laser beam into N paths, where N is an integer from 2 to 1000, etc. Each laser beam in each path is amplified from a first energy level to a second energy level, and each laser beam in each path is matched with a predetermined polarization phase. In one example, the system has a combiner device configured to receive N laser beams and configured to spatially combine the N laser beams into an amplified pulse. The system has an auxiliary device profile coupled to the combiner device and configured to shape the amplified pulse from a first Gaussian profile to a second Gaussian profile. The system has a Fabry-Perot cavity configured to receive the amplified pulse. The cavity has a first reflector device and a second reflector device, and a free space defined between the first reflector device and the second reflector device to form a pair of reflector devices, so that within M cycles of an amplified pulse propagating between the pair of reflector devices, the amplified pulse propagating from the pulse laser device increases in energy intensity from a first intensity to a second intensity and then to an Mth intensity, where M is greater than 10,000 cycles.

[0055] In one example, the system further has a detection device coupled to a portion of one of the mirror devices. The detection device is configured to measure a signal from the amplified pulse to detect a phase and a shape of the amplified pulse.

[0056] In one example, the system further has a charge coupled device (CCD) camera coupled to a portion of one of the mirror devices, the CCD camera being configured to measure a signal from the amplified pulse to detect a phase and shape of the amplified pulse. The CCD camera includes a plurality of detectors configured to detect electromagnetic radiation signals from approximately 400 nanometers to 2000 nanometers.

[0057] In one example, the system has a controller system coupled to the pulsed laser device and to the detection device. In one example, the system has a controller system coupled to the pulsed laser device and the detection device such that a feedback signal is detected from the detection device and sent to the controller device to adjust the phase, shape, and focus of the laser beam from the pulsed laser device.

[0058] In one example, the system has a controller system coupled to a pulsed laser device and a detection device, such that a feedback signal from the amplified pulse is detected by the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device, thereby adjusting the deformation of any pair of mirrors. The system has a controller system coupled to a pulsed laser device and a detection device, such that a feedback signal from the amplified pulse is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device, thereby adjusting the deformation of any pair of mirrors caused by an increase in energy intensity in an alternative example.

[0059] In one example, the Fabry-Perot cavity is configured as a reactor device for a fusion reaction. In one example, the system also has a reactor device coupled to the Fabry-Perot cavity; and a distributor device configured to inject a target into the reactor device so that the target device interacts with the amplified pulse to induce a fusion reaction. In one example, the pulsed laser device includes an oscillator device coupled to an electro-optic modulator configured to adjust the phase of the laser beam, and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by the beam splitter device.

[0060] In one example, the present invention provides a laser system. The system has a pulsed laser device configured to emit a laser beam. The system has a beam splitter device coupled to the pulsed laser device, and is configured to receive the laser beam and split the laser beam into N paths, where N is an integer from 2 to 1000, etc. Each laser beam in each path is amplified from a first energy level to a second energy level, and each laser beam in each path is matched with a predetermined polarization phase. In one example, the system has a combiner device, which is configured to receive N laser beams and is configured to spatially combine the N laser beams into an amplified pulse. The system has an auxiliary device coupled to the combiner device, and is configured to shape the amplified pulse from a first Gaussian profile to a second Gaussian profile. In one example, the system has a Fabry-Perot cavity configured to receive the amplified pulse. The cavity has a first mirror device and a second mirror device, and a free space defined between the first mirror device and the second mirror device to form a pair of mirror devices, so that for M cycles of the amplified pulse propagating between the pair of mirror devices, the amplified pulse propagating from the pulsed laser device increases in energy intensity from a first intensity to a second intensity and then to an Mth intensity, where M is greater than 10,000 cycles. In one example, the system has an optical mode filter that is spatially disposed within a region of the Fabry-Perot cavity and is configured to reflect the parasitic optical mode to a surface region of the Fabry-Perot cavity to maintain the temperature of each mirror within a predetermined temperature range.

[0061] In one example, the predetermined range maintains a shape of each mirror device. In one example, the shape is maintained to prevent any adverse effect on the pulsed laser beam. In one example, the optical mode filter transfers energy from the parasitic optical mode to the wall of the Fabry-Perot cavity. In one example, the optical mode filter includes a knife-edge mirror configured to reflect electromagnetic radiation from the parasitic optical mode.

[0062] In one example, each of the first reflector device and the second reflector device includes sapphire, quartz or silicon carbide or a combination thereof. In one example, each of the first reflector device and the second reflector device is directly or indirectly attached to a heat sink, which includes a heat dissipation and cooling system with a coolant including water, other liquid circulation systems or cooling gas cooling systems to maintain the temperature of each first reflector device and the second reflector device within a predetermined temperature range. In one example, the auxiliary device includes an electro-optic modulator configured to adjust the phase of the laser beam, and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by the beam splitter. In one example, the Fabry-Perot cavity is characterized by an average laser power greater than 1 megawatt.

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[0089] Although the above is a complete description of specific examples, various modifications, alternative structures, and equivalent methods may still be used. For example, a packaged device may include any combination of the above elements, as well as elements outside of this specification. In one example, a high-intensity laser forms a resonator between a pair of mirror devices using constructive interference of each laser beam. In one example, a first path with a high-intensity pulsed laser is provided in a resonator device. In one example, the present invention provides a system and method for generating concentric or spherical resonators within a reaction region to focus the laser at the center of the reactor. In addition, the terms first, second, third, and finally do not imply an order in one or more of the current embodiments.

Claims

1. A laser system comprising: a pulsed laser device configured to emit a laser beam; a beam splitter device coupled to the pulsed laser device and configured to receive the laser beam and split the laser beam into N paths, wherein N is an integer from 2 to 1000, each laser beam in each path is amplified from a first energy level to a second energy level, and each laser beam in each path is matched to a predetermined polarization phase; a combiner device configured to receive the N laser beams and configured to spatially or temporally combine the N laser beams into an amplified pulse; A Fabry-Perot cavity is configured to receive the amplified pulse and includes a first mirror device and a second mirror device and a free space defined between the first mirror device and the second mirror device to form a pair of mirror devices, so that for M cycles of the amplified pulse propagating between the pair of mirror devices, the amplified pulse propagated from the pulse laser device increases in energy intensity from a first intensity to a second intensity and then to an Mth intensity, wherein M is greater than 1000 cycles.

2. The system of claim 1 , further comprising a detection device coupled to a portion of one of the reflector devices, the detection device being configured to measure a signal from the amplified pulse to detect a phase and a shape of the amplified pulse; an auxiliary device coupled to the combiner device and configured to reshape the amplified pulse from a first Gaussian profile to a second Gaussian profile; wherein the first Gaussian profile comprises a quasi-Gaussian profile and the second Gaussian profile comprises a quasi-Gaussian profile; wherein M is greater than 10,000 cycles.

3. The system according to claim 1 further includes a charge coupled device camera coupled to a portion of one of the mirror devices, the charge coupled device camera being configured to measure an attenuation signal from the amplified pulse to detect a phase and a shape of the amplified pulse, the charge coupled device camera comprising a plurality of detectors configured to detect electromagnetic radiation signals from 400 nm to 2000 nm.

4. The system of claim 1, further comprising a controller system coupled to the pulsed laser device and to a detection device.

5. The system of claim 1 , further comprising a controller system coupled to the pulsed laser device and the detection device such that a feedback signal is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device.

6. The system of claim 1 further comprising a controller system coupled to the pulsed laser device and the detection device such that a feedback signal from the amplified pulse is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device, thereby adjusting the deformation of any pair of mirrors.

7. The system of claim 1 , further comprising a controller system coupled to the pulsed laser device and the detection device such that a feedback signal from the amplified pulse is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the pulsed laser device, thereby adjusting the deformation of any pair of mirrors caused by an increase in energy intensity.

8. The system according to claim 1, characterized in that The Fabry-Perot cavity is configured as a reactor device for fusion reaction.

9. The system of claim 1, further comprising a reactor device coupled to the Fabry-Perot cavity; and, A dispenser device is configured to inject a target into the reactor device so that the target device interacts with the amplified pulse to initiate a fusion reaction.

10. The system according to claim 1, characterized in that The pulsed laser device includes an oscillator device coupled to an electro-optic modulator configured to adjust the phase of the laser beam and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by the beam splitter device.

11. The system according to claim 1, characterized in that Each of the first reflector device and the second reflector device includes sapphire, quartz, or silicon carbide, or a combination thereof.

12. The system according to claim 1, characterized in that Each of the first reflector device and the second reflector device is directly or indirectly attached to a heat sink, which includes a heat dissipation and cooling system having a coolant including water, other liquid circulation systems or a cooling gas cooling system to maintain the temperature of each of the first reflector device and the second reflector device within a predetermined temperature range.

13. The system according to claim 1, characterized in that The auxiliary device includes an electro-optic modulator configured to adjust the phase of the laser beam, and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by the beam splitter.

14. The system according to claim 1, characterized in that The Fabry-Perot cavity is characterized by an average laser power greater than 1 mW.

15. A laser system comprising: a laser device configured to emit a laser beam; a beam splitter device coupled to the laser device and configured to receive the laser beam and split the laser beam into N paths, wherein N is an integer from 2 to 1000, each laser beam in each path is amplified from a first energy level to a second energy level, and each laser beam in each path is phase matched to a predetermined characteristic; a combiner device configured to receive the N laser beams and configured to spatially combine the N laser beams into an amplified beam; an auxiliary device coupled to the combiner device and configured to shape the amplified pulse from a first Gaussian profile to a second Gaussian profile; A Fabry-Perot cavity is configured to receive the amplified pulse and includes a first mirror device and a second mirror device and a free space defined between the first mirror device and the second mirror device to form a pair of mirror devices, so that within M cycles of the amplified light beam propagating between the pair of mirror devices, the amplified pulse propagated from the pulse laser device increases in energy intensity from a first intensity to a second intensity and then to an Mth intensity, wherein M is greater than 10,000 cycles.

16. The system of claim 15 , further comprising a detection device coupled to a portion of one of the mirror devices, the detection device configured to measure a signal from the amplified pulse to detect a phase and shape of the amplified light beam; and an optical mode filter spatially disposed within a region of the Fabry-Perot cavity and configured to reflect parasitic optical modes from the Fabry-Perot cavity to maintain a fundamental or lower harmonic optical mode in the Fabry-Perot cavity; wherein the predetermined characteristic is selected from polarization, spatial orientation, phase, or frequency.

17. The system of claim 15, further comprising a charge coupled device camera coupled to a portion of one of the mirror devices, the charge coupled device camera configured to measure a signal from the light beam; wherein the light beam is a continuous or pulsed laser.

18. The system of claim 15, further comprising a controller system coupled to the pulsed laser device and to a detection device.

19. The system of claim 15, further comprising a controller system coupled to the laser device and the detection device such that a feedback signal is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the laser device.

20. The system of claim 15, further comprising a controller system coupled to the laser device and the detection device such that a feedback signal from the amplified light beam is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the laser device, thereby adjusting the deformation of any pair of mirrors.

21. The system of claim 15, further comprising a controller system coupled to the laser device and the detection device such that a feedback signal from the amplified light beam is detected from the detection device and sent to the controller device to adjust the phase, shape and focus of the laser beam from the laser device, thereby adjusting the deformation of any pair of mirrors caused by an increase in energy intensity.

22. The system of claim 15, further comprising a reactor device coupled to the Fabry-Perot cavity; and, A dispenser device is configured to inject a target into the reactor device so that the target device interacts with the amplified pulse to initiate a fusion reaction.

23. The system according to claim 15, characterized in that The pulsed laser device includes an oscillator device coupled to an electro-optic modulator configured to adjust the phase of the laser beam, and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by a beam splitter device.

24. The system according to claim 15, characterized in that The optical mode filter includes a knife-edge mirror configured to reflect electromagnetic radiation from the parasitic optical mode.

25. The system according to claim 15, characterized in that The auxiliary devices are an electro-optic modulator configured to adjust the phase of the laser beam and an acousto-optic modulator configured to adjust the amplitude of the laser beam before the laser beam is received by the beam splitter.

26. The system according to claim 15, characterized in that Each of the first reflector device or the second reflector device is made of sapphire, quartz or silicon carbide or a combination thereof.

27. The system according to claim 15, characterized in that Each of the first reflector device or the second reflector device is directly or indirectly coupled to a heat sink, which includes a heat dissipation and cooling system with water or a coolant circulation system or a cooling gas cooling system to maintain the temperature within a predetermined temperature range.

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