Systems and methods for coherent beam combining

Abstract

To provide multi-channel coherent beam combining (CBC).SOLUTION: Multi-Channel coherent beam combining using a reference optical beam and an array of optical detectors employs a mechanism for phase and / or polarization locking. Each detector is configured and located to detect overall intensity of an optical interference signal caused by interference of the reference beam and a beam of each channel, where the fast intensity per-channel detection allows simultaneous and quick phase / polarization locking of all channels for improving beam combining system performance.SELECTED DRAWING: Figure 5A

Description

[Technical field]

[0001] The present disclosure generally relates to systems and methods for coherent beam combining incorporating phase and / or polarization locking mechanisms. [Background technology]

[0002] High power lasers near the diffraction limit, such as amplified fiber lasers (fiber amplifiers), have a variety of scientific and industrial implementations and allow the achievement of high power output optical signals with excellent beam quality. However, maintaining that near diffraction limit beam quality in a single fiber laser can be limited primarily by three physical phenomena: stimulated Brillouin scattering, stimulated Raman scattering, and modal thermal instability. To overcome these limitations, techniques for combining multiple optical beams are used, which combine multiple optical beams emanating from multiple fiber lasers into a single combined optical beam.

[0003] The technique and system layout used to combine multiple optical beams depends, among other things, on the spectral coherence of these optical beams; combining spectrally coherent optical beams, known as coherent beam combining (CBC), can be performed by using a phased array (also known as "side-by-side CBC"), such as an array of collimators that each collimate separate optical beams. Other techniques for CBC involve the use of one or more diffraction grating elements (also known as "field aperture technology").

[0004] The figures illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0005] For simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, dimensions of some of the elements may be exaggerated relative to other elements for clarity of presentation. Additionally, reference numerals may be repeated among the figures to indicate corresponding or similar elements. Reference to previously presented elements is implied without necessarily further reference to the drawing or description in which they appear. The figures are as follows: [Brief description of the drawings]

[0006] [Figure 1A] The far-field (FF) beam distribution of a CBC for multiple input optical beams with asynchronous phase and randomly oriented polarization is shown. [Figure 1B] FF beam distribution of a CBC for multiple input optical beams with synchronized phase and regularly oriented polarization is shown. [Diagram 2] A CBC system 1000 for combining M×N temporally coherent input optical beams using a high-speed phase and polarization locking mechanism is shown in accordance with some embodiments. [Figure 3A] FF beam distribution of a CBC for multiple input optical beams with asynchronous phase and randomly oriented polarization is shown. [Figure 3B] 1 illustrates the FF beam distribution of a CBC of multiple input optical beams with synchronized phases and locked regularly oriented polarizations using a CBC system with phase and polarization locking mechanisms according to some embodiments. [Figure 4A] 1 illustrates composite output optical beam steering, according to some embodiments, based on reference optical beam steering using a CBC system with phase and / or polarization locking, where the reference optical beam has a plane wavefront and is propagated such that the composite output optical beam is steered to a zero steering angle. [Figure 4B]1 illustrates composite output optical beam steering, according to some embodiments, based on reference optical beam steering using a CBC system with phase and / or polarization locking, where the reference optical beam has a plane wavefront and is propagated such that the composite output optical beam is steered to a non-zero steering angle. [Figure 4C] 1 illustrates composite output optical beam steering, according to some embodiments, based on reference optical beam steering using a CBC system with phase and / or polarization locking, where the reference optical beam has a parabolic wavefront and is propagated such that the composite output optical beam is steered to a zero steering angle. [Figure 4D] 1 illustrates composite output optical beam steering, according to some embodiments, based on reference optical beam steering using a CBC system with phase and / or polarization locking, where the reference optical beam has a parabolic wavefront and is propagated such that the composite output optical beam is steered to a non-zero steering angle. [Figure 5A] 1 illustrates a CBC system configured to enable phase and / or polarization locking having a controllable phased array wavefront control mechanism including multiple phase control modules, according to some embodiments. [Figure 5B] 5B illustrates the CBC system of FIG. 5A used for wavefront steering control, according to some embodiments. [Figure 5C] 5B illustrates the CBC system of FIG. 5A used for wavefront collimation control, according to some embodiments. [Figure 6] 1 illustrates a process for CBC phase locking, according to some embodiments. [Figure 7] 1 illustrates a process for CBC polarization locking, according to some embodiments. [Figure 8] 1 illustrates a combined output optical beam wavefront control process using a CBC system with wavefront control according to some embodiments. [Figure 9] 1 illustrates the process of CBC system phase locking and composite output optical beam wavefront control based on received target data. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Coherent beam combining (CBC) aims to combine several temporally coherent input optical beams with the same optical wavelength or overlapping wavelength bands into a single coherent combined optical beam of a single wavelength or narrow wavelength band. The implementation of CBC often requires the maintenance of high beam quality, e.g., enabling high, far-field (FF) spatial and / or spectral beam coherence.

[0008] In some cases, multiple optical amplifiers, such as fiber lasers (e.g., doped fibers), may be used to provide the input optical beam, allowing for the steering of light emitted from one or more light sources and power scaling of the light guided therethrough.

[0009] The terms "doped optical fiber" or "doped fiber" refer to any type of optical fiber that is doped with one or more elements, such as, but not limited to, erbium, dysprosium, ytterbium, neodymium, thulium, praseodymium, and / or holmium.

[0010] The terms "optical beam," "light beam," and / or "beam" as used (interchangeably) herein may refer to any propagating electromagnetic signal, field, and / or wave in the optical wavelength range.

[0011] The term "beam quality" may refer to any one or more beam characteristics, such as, but not limited to, wavefront (profile) quality, beam waist, beam radius, beam divergence, beam intensity / amplitude, beam brightness level (radiance), phase shift (phase coherence), etc., and / or the maintenance of these beam characteristics over time and / or distance.

[0012] As used herein, the term "temporally coherent optical beam" or "temporally coherent input optical beam" may refer to multiple optical beams having correlated electromagnetic fields, for example, where the frequency bandwidth Δf of the optical beams is inversely proportional to the temporal coherence time. For example, coherent optical beams may be temporally coherent by having the same signal modulation, the same or overlapping frequency / wavelengths, and / or the same or overlapping frequency / wavelength bandwidths.

[0013] To achieve a CBC with FF high beam quality, the phase and polarization of the input optical beams to be combined should be controlled so that the phase / polarization is identical for all input optical beams, or so that the phases of the input optical beams are at a desired specific difference from each other (e.g., in the case of FF beam steering).

[0014] In many cases, the input optical beams have unknown phase and / or polarization, and the phase and / or polarization of each input optical beam can be unstable, i.e., change rapidly over time, causing phase asynchrony between the input optical beams, which dramatically affects the FF beam quality of their combined optical beam.

[0015] The light source(s) and optical waveguides, such as fiber lasers, used as the source of the input optical beam can be very sensitive to environmental conditions and / or changes in those conditions, such as vibration, shaking, temperature, etc., such that under some environmental conditions, the phase of the input optical beam can change significantly, ranging from every few milliseconds to every few microseconds. Typically, the polarization changes under unstable conditions, ranging from every few seconds to every tenth of a second. The phase of the input optical beam typically changes several times faster than the rate of change in polarization when under unstable conditions.

[0016] Figure 1A shows the FF beam distribution of a CBC for multiple input optical beams with asynchronous phase and randomly oriented polarizations. It is clear that in this case, the FF wavefront of the combined beam will show a distribution of scattered light with no central lobe.

[0017] Figure 1B shows the FF beam distribution of the CBC of multiple input optical beams with synchronized phase and regularly oriented polarization. In this case, it is clear that the FF wavefront of the combined beam shows a central lobe that concentrates most of the FF power of the combined optical beam into a much smaller angular spot size, resulting in a high-quality wavefront spatial distribution.

[0018] Aspects of the disclosed embodiments relate to systems and methods for CBC incorporating closed-loop parallel phase and / or polarization locking mechanisms that provide high speed phase and / or polarization locking to provide high quality and high power CBC that can withstand a variety of environmental and other conditions that cause rapid phase and / or polarization changes and changes in such conditions.

[0019] According to some embodiments, the CBC systems and methods allow for the combination of multiple input optical beams (defining multiple channels) with automatic multi-channel closed-loop phase and / or polarization locking, e.g., by using one or more reference optical beams and multiple optical detectors, where the phase and / or polarization locking is based entirely on intensity readings from the optical detectors and does not require calculation of optimal phase and / or polarization for each channel, thereby allowing for rapid phase and / or polarization locking.

[0020] According to some embodiments, the system is configured for CBC of an M×N array of multiple temporally coherent input optical beams defining M×N channels, where each channel may be defined as all transformations of a respective single input optical beam, where M and / or N are non-zero integers, M indicating the number of rows in the array and N indicating the number of columns in the array.

[0021] Phase / polarization locking may be performed in a continuous parallel closed-loop manner, for example, for all channels simultaneously and separately.

[0022] According to some embodiments, the CBC system and method include: providing an M×N array of temporally coherent input optical beams and a reference optical beam; generating M×N output optical beams corresponding to the M×N input optical beams (e.g., by using an M×N array of collimating elements), such that the output optical beams propagate parallel along a first propagation direction; splitting each of the output optical beams such that a first portion of each of the output optical beams is directed toward a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam and a second portion of each of the output optical beams is directed toward a second propagation direction and is used as a sample optical beam; directing a reference optical beam such that the reference optical beam interferes with the sample optical beam to generate a plurality of corresponding optical interference signals; providing a plurality of M×N optical detectors, each arranged and configured to measure the overall intensity of a respective one of the optical interference signals and to simultaneously and sequentially generate power output values ​​indicative of the detected intensity of its respective optical interference signal; automatically and separately varying the phase of each of the input optical beams while comparing the measured power output value of its corresponding optical interference signal to at least one previously measured power output value produced by a respective optical detector; Locking the phase of the input optical beam when the extreme (maximum or minimum) power output value of its respective optical interference signal is reached It can be configured as follows.

[0023] The above process may be performed such that the system separately phase locks each channel when a maximum intensity of the respective interference optical signal is reached, which occurs in the case of constructive interference between the reference optical beam and each sample optical beam, or a minimum intensity of the respective interference optical signal is reached, which occurs in the case of destructive interference between the reference optical beam and each sample optical beam.

[0024] An aspect of the disclosed embodiment is a system for coherent beam combining (CBC), comprising: a light source generating a source optical beam; a beam splitting mechanism configured to split a source optical beam into an array of M×N temporally coherent input optical beams and a reference optical beam; an array of M×N collimating elements configured to direct each of the input optical beams through a separate collimating element to generate M×N output optical beams corresponding to the input optical beams passed through the collimating elements, the output optical beams being parallel to one another and defining a first propagation direction; a beam splitting element configured to split each of the output optical beams such that a first portion of each of the output optical beams is directed towards a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam, and a second portion of each of the output optical beams is directed towards a second propagation direction and is used as a sample optical beam; a plurality of optical detectors, each arranged and configured to measure the overall intensity of a respective optical interference signal and to output a corresponding power output value; a control subsystem configured to continuously receive the measured power output values ​​from each of the optical detectors, vary the phase of each of the input optical beams while comparing the measured power output value of the respective optical interference signal to at least one previously measured power output value from a respective optical detector, and lock the phase of the input optical beam when an extreme power output value of the respective optical interference signal is reached; The present invention provides a system that may include:

[0025] According to some embodiments, varying the phase of each input optical beam may be performed directly based on the measured power output value of its respective optical interference signal, without calculating or estimating the exact phase and / or without generating any other signal associated therewith.

[0026] According to some embodiments, the system may be configured to lock the phase and / or polarization of each respective channel to only a single extremum type for all channels, i.e., lock all channels when their respective maximum intensity is reached or when their respective minimum intensity is reached.

[0027] According to some embodiments, varying the phase and / or polarization of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal, without calculation, estimation, or prior knowledge of the exact phase / polarization and / or without generating any other signal associated therewith. This means that only the identification (e.g., by comparison) of the maximum / minimum intensity of each channel is used to automatically lock the phase / polarization of each channel. For example, the phase of each input optical signal can be shifted up or down in equal phase steps that differ from each other by a phase shift span Δφ, and for each phase shift, the intensity of each interference optical signal of the channel is measured to find the extremum of the intensity of the respective channel within the time span. According to some embodiments, the phase shift span Δφ can be selectively controllable and / or adjustable.

[0028] According to some embodiments, the phase / polarization locking mechanism may be configured such that an updated intensity reading (i.e. the last power output value of each detector) is compared only with one consecutive previously measured intensity reading of each optical detector of each channel. In other embodiments, the previously measured intensity readings of each channel within a given detection time span may be used to identify extreme intensity values.

[0029] The terms "reading", "detector reading(s)", "intensity reading(s)", "intensity value" and the like may refer to and be used interchangeably with the term "power output value(s)" of the optical detector(s).

[0030] According to some embodiments, the extremum can be identified only after the phase has been shifted several times within a certain (short) time span (e.g., microseconds) and the extremum is selected from those several measured intensities.

[0031] According to some embodiments, to lock the phase of a particular input optical beam, the system may be configured to shift the phase upwards or downwards from its last state, for example by increasing or decreasing the phase over a phase shift span Δφ to reach a phase location that provides a detector reading of maximum intensity (herein the “extreme phase”) while checking whether the intensity has increased (where a desired maximum extremum is achieved).

[0032] According to some embodiments, the polarization of the input optical beam may be linear or elliptical, and the polarization control mechanism (ie, the "polarization locking mechanism") may be configured for linear or elliptical polarization control.

[0033] According to some embodiments, the CBC process may further include controlling one or more characteristics of the wavefront of the combined output optical beam, such as the far-field (FF) distribution of the wavefront, the FF location of a central lobe that can be formed by the combined output optical beam, focusing characteristics of the central lobe, spatial configuration of the wavefront, and environmental optical aberration correction.

[0034] In some embodiments, controlling one or more wavefront characteristics may be performed by controlling the direction of the wavefront of the reference optical beam (beam steering), for example by mechanically moving an output end of an optical waveguide from which the reference optical beam is output, and / or by mechanically varying the relative positioning between the output end of the optical waveguide and a focusing lens located in the path of the reference optical beam.

[0035] According to some embodiments, control of one or more wavefront characteristics may be performed using an M×N array of phase control modules (PCMs), each arranged and configured to control the phase of a different portion of the reference optical beam that interferes with a respective sample optical beam.

[0036] According to some embodiments, the PCM used may be electronically and / or digitally controllable. For example, a liquid crystal spatial light modulator (SLM) may be used as a PCM for phased array wavefront control to provide a low power electronically controllable PCM. In other cases, an array of electronically and / or mechanically controllable steering mirrors may be used.

[0037] According to some embodiments, control of one or more characteristics of the wavefront of the combined output optical beam may be performed according to the FF position of the target to which the combined optical beam is to be directed.

[0038] According to some embodiments, the position (e.g., distance and angular position) of the target relative to the composite output beam position may be detectable, for example, by using a target detection device or system configured to detect at least the position of the target (e.g., a 3D detector), and optionally other characteristic values ​​of the target, such as target type, speed, material composition, etc., and transmit target-related data (also "target data" herein) indicative of the target characteristic values ​​to the CBC system for wavefront control based on at least the received target-related data.

[0039] According to some embodiments, the phase and / or polarization of the reference optical beam (φref and Pref, respectively) may be constant, i.e., have a rate of change substantially slower than the rate of change of the phase and / or polarization of the input optical beam, or exhibit no change in phase and / or polarization over time.

[0040] According to some embodiments, phase locking can be performed by synchronizing the phase of all input optical beams with that of a reference optical beam, e.g. equal to the phase φ of the reference optical beam, or, in the case of wavefront steering, by shifting each phase of each channel by a desired shift ratio Δφ with respect to one or more adjacent channels.

[0041] For example, if a beam angle θbeam,x is desired (assuming only the x direction is processed and the distance between adjacent segments is equal across the M×N array along the x and y directions), the following phase distribution is required:

number

[0042] where Δxseg is the size of the segment at the array system output and λlaser is the wavelength of the laser (light source). The same holds for the case where a tilted beam θbeam,y is desired in the y direction:

number

[0043] Here, the value of the maximum phase difference between adjacent segments should be less than 2π.

[0044] According to some embodiments, the input optical beam and the reference optical beam may originate from the same single light source or from different light sources.

[0045] According to some embodiments, the input optical beam may originate from a single light source or from multiple light sources.

[0046] Referring now to FIG. 2, a CBC system 1000 for combining M×N temporally coherent input optical beams (IOBs) using a high-speed phase and polarization locking mechanism is shown generally in accordance with some embodiments.

[0047] The CBC System 1000 is A single light source 1100 configured to output light at a single wavelength λ or a narrow wavelength band Λλ; a beam splitting mechanism for splitting the output light from the light source 1100 into a reference optical beam (ROB) 1210 and M×N IOBs 1110; an array of M×N phase shifters (PS) 1800, each PSij configured to control the phase of a respective (different) IOBij of a respective ij channel; an array of M×N polarization controllers (PC) 1850, each PCij configured to control the polarization of a respective (different) IOBij of a respective ij channel; an M×N array of collimating elements (CE) 1300, each CE arranged and configured to collimate a respective IOBij of a different respective ij channel; a beam splitter 1400 constructed and arranged to simultaneously split incoming M×N IOBs 1110 into M×N sample optical beams (SOBs) 1221 and combined output optical beams (COOBs) 1900, where the COOBs 1900 are oriented toward a first propagation direction defining an axis x, the SOBs 1221 are oriented toward a second propagation direction defining an axis y that is angled relative to the axis x (where x may be perpendicular to y), and the ROB 1210 may be oriented along a y-axis defined by the propagation direction of the SOB 1221 to enable the SOB 1221 to optically interfere with the ROB 1210; an M×N array of optical detectors such as point detectors (PD) 1600, where each PDij is constructed and arranged to detect the intensity of a respective Optical Interference Signal (OIS), i.e. OISij, which is a signal formed by optical interference between a respective SOBij and the ROB 1210, and where each PDij may be configured to output a power output value indicative of the measured intensity of a respective channel ij at a respective time; a control subsystem 1700 associated with the M×N array of PDs 1600, PSs 1800, and PCs 1850 to enable continuous and parallel reception of power output values ​​from each PD 1600 and to control the phase and / or polarization of each channel based on its respective received power output value; may include.

[0048] According to some embodiments, the control subsystem 1700 may include an array of M×N processing modules (PM), each PMij configured to receive a power output value of a respective PDij and to control the phase and polarization of a respective IOBij via a respective PCij and PSij based on the power output value received from the respective PDij.

[0049] According to some embodiments, the control of the phase and / or polarization of each IOBij may be performed by gradually increasing or decreasing the phase and / or gradually changing the polarization state, for example to provide an increase in intensity (power output value) in the PDij readings, in order to lock the phase and / or polarization when a maximum interference light signal value is reached. This may be done by comparing the current PDij readings with one or more previously measured intensities of the respective ij channel. According to some embodiments, this may require stepping back from the current phase and / or polarization values ​​when passing through an intensity extreme.

[0050] According to some embodiments, the control subsystem 1700 may include one or more processing, control, and / or memory modules for enabling (temporary and / or long-term) storage of current and previously measured power output values ​​of each PD, processing the received power output values ​​for identifying the extreme phase and / or polarization of each channel, and / or for controlling at least the PC 1850 and / or the PS 1800 for identifying the optimal (locked) phase / polarization and phase / polarization locking of each channel, e.g., by sending control commands instructing only the direction of increase / decrease of the phase / polarization shift.

[0051] According to some embodiments, the phase and / or polarization control may also include controlling the phase and / or polarization shift span, for example, the phase shift span may be reduced once regions of extreme intensity are identified in order to fine-tune the phase lock.

[0052] According to some embodiments, as shown in FIG. 2, a CBC system 1000 includes: a first optical waveguide 1101, which may be an optical fiber, configured to connect to one output node of the light source 1100 and guide light from the light source 1100 to a beam splitting device 1102 configured to split the light guided by the first optical waveguide 1101 into M×N IOBs 1110, for example by having M×N optical fibers guiding the M×N IOBs 1110; a second optical waveguide 1201, such as a second optical fiber, configured to connect to a second output node of the light source 1100 and direct light to a distal fiber end thereof, which may be held by a ferrule holder element 1203 for outputting the ROB 1210; a reference beam collimator 1205, such as one or more collimating lenses, mirrors, and / or diffractive optical elements (DOEs), positioned relative to the output end of the second optical waveguide, e.g., the positioning of an edge of the holder element 1203, such that the ROB 1210 is collimated (e.g., by placing the reference beam collimator 1205 at a focal plane and / or focus of the reference beam collimator 1205); It may further include.

[0053] According to some embodiments, as shown in FIG. 2, the CBC system 1000 may further include an M×N array of sampling collimating elements (SCEs) 1500, each SCE arranged and configured to enhance (e.g., by focusing) the optical signal received on a respective PD resulting from interference between SOB and ROB 1210 for the respective ij channel.

[0054] According to some embodiments, the light source 1100 may include any type of light source capable of outputting light at a single wavelength and / or a single narrow wavelength band, such as a light emitting diode (LED), a monochromatic and / or tunable laser device, etc.

[0055] According to some embodiments, each PSij may be configured to control the phase of each IOBij by being electronically and / or computer controlled, for example by its respective PMij being configured to vary the phase based on received signal power values, input voltage or current values ​​applied to each PSij, etc. The received signal power values ​​may only indicate the direction of the phase shift (increase or decrease).

[0056] According to some embodiments, each PMij may be configured to control the polarization of each IOBij by being electronically and / or computer controlled, e.g., by each PMij being configured to vary the polarization based on received signal power values, input voltage or current values ​​applied to each PMij, etc. The received signal power values ​​may only indicate the polarization shift state (e.g., in the case of elliptical polarization, the change in ellipticity and / or the angle of the polarization vector(s)).

[0057] According to some embodiments, each PSij may include any type of phase shifting device and / or element configured to receive a control command (e.g., input power / voltage change) and in response shift the phase of the respective IOBij, preferably within a time span faster than the time rate of change of the natural IOB phase. PS 1800 may include, for example, a spatial light modulator (SLM), a device including an electrically / electronically controllable deformable mirror, a microelectromechanical system (MEMS) such as a microelectromechanical optical system (e.g., a mirror), etc.

[0058] According to some embodiments, each PCij may include any type of polarization control device and / or element configured to receive control commands (e.g., input power / voltage changes) and in response change the polarization state of the respective IOBij, preferably within a time span faster than the time rate of change of the IOB's natural polarization. PC 1850 may include, for example, a piezoelectric element(s) based controller, a LiNO2 (LN) controller, etc.

[0059] Figures 3A and 3B show the effect that results from using a fast CBC system with a phase-locking mechanism as shown above: Figure 3A shows the FF beam distribution that results from CBC of multiple input optical beams with asynchronous phases and polarizations, and Figure 3B shows the result of using a fast CBC system with a phase-locking mechanism.

[0060] 4A, 4B, 4C, and 4D, there is shown a wavefront control mechanism of the COOB 1900 that enables beam steering of the COOB 1900 by controlling the relative positioning between the reference beam collimator 1205 and a holder element 1203 that holds the output node of the second optical waveguide 1201 that directs the reference optical beam (ROB), in some embodiments.

[0061] 4A shows a ROB with a plane wavefront propagating along the y-axis. In this case, the holder element 1203 and the reference beam collimator 1205 are both positioned such that the planar ROB propagates along the y-axis, where the focal point of the reference beam collimator 1205 is also located. In this configuration, all SOBs travel through the same optical path length (OPL) and are oriented parallel to the propagation direction of the ROB, and upon operation of the CBC system 1000, the phase and / or polarization of all channels will automatically lock to the same phase and / or polarization, resulting in a COOB 1900 with a plane wavefront steered (oriented) parallel to the x-axis (perpendicular to the direction of the ROB).

[0062] 4B shows an ROB with a plane wavefront propagated at an angle to the y-axis, e.g., at a non-zero angle β relative to the y-axis, in which case the resulting COOB will be tilted at the angle β.

[0063] In this case, the holder element 1203 is positioned shifted a distance from the axis defined by the focal point of the reference beam collimator 1205, for example, by shifting the holder element 1203 and / or the reference beam collimator 1205 along the x-axis. In this configuration, each SOB in each jth row of M×N channels is directed through a different optical path length (OPL) and interferes with an angularly shifted ROB. In this case, during operation of the CBC system 1000, the phase and / or polarization of adjacent channels in each row j is Δxsteering=Fl β where Fl is the focal length of the beam collimator 1205. The automatic phase difference between adjacent channels (segments) is

number

[0064] 4C shows a ROB with a parabolic wavefront that is propagated parabolically symmetrically about the y-axis. In this case, the holder element 1203 and the reference beam collimator 1205 are both positioned such that the parabolic ROB is propagated symmetrically about the axis y, where the focal point of the reference beam collimator 1205 is also located. In this configuration, during operation of the CBC system 1000, the phase and / or polarization of all channels will automatically lock to the optimal phase and / or polarization, resulting in a COOB 1900 with a parabolic wavefront that is steered (oriented) parallel to the x-axis (perpendicular to the direction of the ROB).

[0065] 4D shows a ROB with a parabolic wavefront propagated symmetrically about axis w that forms a non-zero angle β with the y-axis. In this case, the focal points of the holder element 1203 and the reference beam collimator 1205 can be shifted from each other by sh1 along axis x and sh2 along axis y. This can be achieved by shifting (moving) the holder element 1203 and / or the reference beam collimator 1205 along the x-axis and y-axis.

[0066] In this configuration, during operation of the CBC system 1000, the phase and / or polarization of the channels of each row j will automatically lock to the optimal phase and / or polarization, resulting in a COOB 1900 having a parabolic wavefront that is steered (oriented) at an angle relative to the x-axis and / or y-axis.

[0067] According to some implementations, to enable wavefront control manipulation, the CBC system 1000 may further include a steering mechanism that enables control (e.g., electronic and / or computer-based control) of one or more mechanical elements and / or devices to physically change the relative alignment between the focal axis of the reference beam collimator 1205 and the initial output direction of the ROB when exiting the reference beam optical waveguide output node.

[0068] 5A, 5B, and 5C, a CBC system 2000 is shown configured to enable phase and / or polarization locking and control the wavefront of a combined output optical beam by using an electronically controllable phased array wavefront control mechanism including multiple PCMs 2850 in accordance with some embodiments.

[0069] The CBC system 2000 may include any mechanism for providing and controlling the M×N array of IOBs 2110 and directing them towards a beam splitter 2400 (e.g., by using an M×N array of collimating elements 2300) to split the IOBs 2110 into a COOB 2900 propagating in a first propagation direction along the x' axis, and an array of M×N SOBs propagating along a second propagation direction (e.g., perpendicular to the first propagation direction and parallel to the axis y'), while controlling the respective phase and / or polarization of each separate IOB via the M×N arrays of PSs 2800 and PCs 2850, respectively, e.g., by using a control subsystem 2700 operatively associated therewith.

[0070] The CBC system 2000 may further include an M×N array of electronically and / or computer controlled PCMs 2001, an M×N array of PDs 2600, a reference optical beam source 2201, a reference beam collimator 2205, and an output collimator 2002 configured to focus the COOB 2900.

[0071] The PCM 2001 may be located between the beam splitter 2400 and the reference beam source 2201 (e.g., after the reference beam collimator 2205) to phase shift each portion of the reference optical beam (here, the reference optical beam (ROB) for each ij channel (i.e., ROBij)) in a separately controllable manner, for example, to enable beam steering of the COOB 2900.

[0072] The PCM 2001 may include, for example, liquid crystal SLMs, each separately electronically controllable, allowing a different phase to be set for each ROB in each channel, for example to enable beam steering of the COOB 2900.

[0073] Phase and / or polarization locking may be performed by closed-loop iterative modification of the phase and / or polarization of each IOBij based on the intensity readings from its associated PDij such that the phase and / or polarization of each channel ij is locked when the intensity readings of the respective PDij of the channel are at their maximum / minimum intensity values. For example, the maximum intensity value of each channel ij may be achieved when the interference between the respective IOBij and ROBij is fully constructive, producing a respective maximum intensity of OISij.

[0074] For example, if the target 20 is located on the x'z' plane (as shown in FIG. 5B) at the FF from the CBC system 2000 and the target is at the 0,0,0 position of the x'y'z' axes (where x', for example, is defined by the propagation direction of the COOB 2900), then the phases of all the IOBs should be equal to each other. In this case, the PCM can be set to have all the phases of all the ROBs be equal to each other to enable the CBC system 2000 to automatically lock onto each of the IOBs 2110 when they reach the extreme intensity values ​​of their respective OIS. When the target is at a shifted position, for example, a position shifted by d from the 0,0,0 position on the x'y'z' axes (for example, a position 0,d,0 as shown in FIG. 5B ), the phases of the ROBs of each row N can each be set to different values ​​to steer the wavefront of the COOB 2900 to the position 0,d,0 of the target 20 by automatically locking each of the IOBs 2110 to an optimal (different) phase value when the maximum / minimum intensity value of their corresponding OIS is reached.

[0075] According to some embodiments, an output beam collimating device 2002, such as one or more focusing lenses, may be used to allow control of the focusing positioning, such as the focal length, of the COOB 2900.

[0076] If wavefront control of the COOB 2900 additionally or alternatively requires focusing control of the COOB wavefront, for example by controlling the focus or focal plane of the COOB 2900, the output beam collimating device 2002 may enable the relative positioning of one or more of its collimating elements (e.g., lenses) to be mechanically shifted in an electronically and / or computer-controllable manner.

[0077] FIG. 5C shows an exemplary case in which the target 20 may be positioned at a focal length D1 of the output beam collimating device 2002 along the x' axis or may be shifted a distance D2 along the x' axis, in which case the output beam collimating device 2002 may be adjusted (e.g., by electronically controlling the relative positioning of several lenses) to focus the COOB 2900 at focal length D2.

[0078] According to some embodiments, the CBC system 2000 may further include an M×N array of sampling collimating elements (SCEs) 2500, each SCE arranged and configured to focus light resulting from interference between SOBij and ROBij 1210 for a respective ij channel onto a respective PDij.

[0079] According to some embodiments, the IOB 2110 and the ROB may all originate from a single monochromatic light source, such as light source 2100.

[0080] 6, a process for CBC phase locking is shown, according to some embodiments. The process includes: providing an M×N array of temporally coherent input optical beams and a reference optical beam (61); generating (62) M×N output optical beams corresponding to the M×N input optical beams, the output optical beams propagating along a first propagation direction; splitting (63) each of the output optical beams such that a first portion of each of the output optical beams is directed toward a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam and a second portion of each of the output optical beams is directed toward a second propagation direction and is used as a sample optical beam; directing (64) a reference optical beam such that the reference optical beam interferes with the sample optical beam to generate a plurality of optical interference signals; providing a plurality of M×N optical detectors (65), each arranged and configured to measure a respective intensity of each optical interference signal of the plurality of optical interference signals to simultaneously and sequentially generate corresponding power output values; automatically and separately varying a phase of each of the input optical beams while comparing the measured power output value of the respective optical interference signal to at least one previously measured power output value produced by a respective optical detector, where varying the phase of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal (66); locking (67) the phase of each respective input optical beam when the extremum power output value of its respective optical interference signal is reached; may include.

[0081] 7, a process for CBC polarization locking is shown, according to some embodiments. The process includes: providing an M×N array of temporally coherent input optical beams and a reference optical beam (71); generating (72) M×N output optical beams corresponding to the M×N input optical beams, the output optical beams propagating along a first propagation direction; splitting (73) each of the output optical beams such that a first portion of each of the output optical beams is directed toward a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam and a second portion of each of the output optical beams is directed toward a second propagation direction and is used as a sample optical beam; directing (74) a reference optical beam such that the reference optical beam interferes with the sample optical beam to generate a plurality of optical interference signals; providing a plurality of M×N optical detectors (75), each arranged and configured to measure a respective intensity of each optical interference signal of the plurality of optical interference signals to simultaneously and sequentially generate corresponding power output values; automatically and separately varying the polarization of each of the input optical beams while comparing the measured power output value of each optical interference signal to at least one previously measured power output value generated by a respective optical detector, where varying the polarization of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal (76); locking (77) the polarization of each respective input optical beam when an extremum power output value of its respective optical interference signal is reached; may include.

[0082] Referring to Figure 8, a wavefront control process is shown using a CBC system with wavefront control according to some embodiments. The process includes: Receiving target data (81), e.g., indicative of one or more target characteristic values, such as target location, motion characteristic values ​​(e.g., velocity), etc.; Determining value(s) of control parameter(s) for COOB wavefront control (e.g., determining focusing and / or steering related parameter values ​​for focusing and / or steering the COOB towards the target based on the target placement target data) (82); Controlling (83) the wavefront of the COOB based on the value(s) of the determined control parameter(s), for example by generating and transmitting control commands and / or control signals for electronic / computer control of focusing devices and / or steering mechanisms capable of controllably varying the phase of each portion of the reference optical beam or each reference optical beam; automatically and separately varying the phase and / or polarization of each of the input optical beams while comparing the measured power output value of each optical interference signal to at least one previously measured power output value generated by a respective optical detector (84), wherein varying the phase / polarization of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal; locking (85) the phase and / or polarization of each respective input optical beam when an extremum power output value of its respective optical interference signal is reached; may include.

[0083] Referring to Figure 9, an embodiment of a process for CBC system phase locking and COOB wavefront control based on received target data using MxN channels and MxN PCM is shown. This process includes: receiving target data and setting a phase of each of the reference optical beams based on the received target data (91), e.g., using an M×N array of PCMs; For each ij channel, receiving (92) a current intensity reading of PDij (at time tc); storing (93) the current reading of the received PDij; If the intensity reading of the respective channel ij is not the first (94), comparing (95) the received intensity reading PDij with one or more previously received intensity readings PDij (e.g., a limited number of previous intensity readings taken within a limited time span) and checking (96) whether the current intensity reading is higher or lower than at least one of the one or more previously received intensity readings of the respective channel ij; If an optimal phase of IOBij that provides an extreme intensity reading within the time span is identified (96), the optimal phase is locked (97); If no optimal phase has been identified, then the direction of phase change (e.g., increase or decrease) is determined and the respective phase of IOBij is modified (98). may include.

[0084] Steps 92-98 may be repeated for each channel, for a given time span, to lock onto the optimal phase for each respective channel in a fast and efficient manner.

[0085] According to some embodiments, all of the above phase and / or polarization locking mechanisms enable extremely fast and efficient phase / polarization locking, which may enable the phase / polarization to be locked within a locking time T that is faster than or equal to the rate of change of the phase / polarization of the input optical beam, regardless of environmental or other conditions that affect the phase / polarization value instability (e.g., rate of change and / or phase / polarization value fluctuation) of the input optical beam.

[0086] Working Example Example 1 is a method for coherent beam combining (CBC), comprising: generating a source optical beam using a light source; Splitting a source optical beam into an M×N array of temporally coherent input optical beams and a reference optical beam; generating M×N output optical beams corresponding to the M×N input optical beams, the output optical beams propagating along a first propagation direction; splitting each of the output optical beams such that a first portion of each of the output optical beams is directed toward a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam and a second portion of each of the output optical beams is directed toward a second propagation direction and is used as a sample optical beam; directing a reference optical beam such that the reference optical beam interferes with the sample optical beam to generate a plurality of corresponding optical interference signals; providing a plurality of M×N optical detectors, each arranged and configured to measure an overall intensity of a respective optical interference signal and to generate a power output value indicative of the detected overall intensity of its respective optical interference signal; automatically and separately varying the phase of each of the input optical beams while comparing the measured power output value of its corresponding optical interference signal with at least one previously measured power output value generated by a respective optical detector, wherein varying the phase of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal, without calculating or estimating the exact phase and / or generating any other signal associated therewith; locking the phase of the input optical beam when the extremum power output value of the respective optical interference signal is reached. Including, The generation of the optical interference light signal, the measurement of the power output values ​​of the multiple optical detectors, and the phase locking are performed continuously and simultaneously for all M×N input and output optical beams and optical interference signals. This is the method.

[0087] In Example 2, the subject matter of Example 1 may include that varying the phase of each input optical beam is performed using M×N phase shifters (PS), each PS configured to vary the phase of a respective input optical beam, and M×N control modules (CM), each CM associated with a different PS and corresponding optical detector, and configured to repeatedly send control commands to its associated PS based on power output values ​​received from the respective optical detector.

[0088] In Example 3, the subject matter of Example 2 may include that the control commands for each input PS may include instructing only the direction of increase or decrease in the respective phase, such that each PS increases or decreases the phase of its respective input optical beam by a predetermined and / or controllable phase shift span Δφ.

[0089] In Example 4, the subject matter of any one or more of Examples 1-3 may include that the step of generating the output optical beam is performed using an array of M×N collimating elements for separately collimating each of the input optical beams.

[0090] In Example 5, the subject matter of any one or more of Examples 1-4 can include where the method can further include controlling one or more characteristics of a wavefront of the combined output optical beam.

[0091] In Example 6, the subject matter of Example 5 further comprises: Far-field (FF) distribution of wavefront, FF position of the central lobe that can be formed by the combined output optical beam; Focusing characteristics of the central lobe, The spatial organization of the wavefront, Environmental Optical Aberration Correction This includes including one or more of the following:

[0092] In Example 7, the subject matter of any one or more of Examples 5-6 can include where controlling the one or more wavefront characteristics is performed by controlling a direction of a wavefront of a reference optical beam.

[0093] In Example 8, the subject of Example 7 is that the control of the wavefront of the reference optical beam is mechanically moving the output end of the optical waveguide from which the reference optical beam is output; and / or Mechanically varying the relative position between the output end of the optical waveguide and a focusing lens located in the path of the reference optical beam. The method may include performing the method by

[0094] In Example 9, the subject matter of any one or more of Examples 5-6 may include that the control of the one or more wavefront characteristics is performed using an M×N array of phase control modules (PCMs), each PCM arranged and configured to control the phase of a different portion of the reference optical beam that interferes with a respective sample optical beam.

[0095] In Example 10, the subject matter of Example 9 can include where the M×N array of PCMs is electronically and / or digitally controllable.

[0096] In Example 11, the subject matter of Example 10 can include where the M×N array of PCMs comprises an M×N array of spatial light modulators.

[0097] In Example 12, the subject matter of any one or more of Examples 5-11 can include controlling one or more characteristics of a wavefront of the combined output optical beam according to a target FF position.

[0098] In Example 13, the subject matter of any one or more of Examples 1 to 12 may include that the method may further include controlling a polarization of each of the input optical beams based on a received power output value of its respective optical interference signal.

[0099] In example 14, the subject matter of example 13 further comprises controlling the polarization of each of the input optical beams by: automatically and separately varying the polarization of each of the input optical beams while comparing the measured power output value of the respective optical interference signal with at least one previously measured power output value from a respective optical detector; and locking the polarization of each respective input optical beam upon reaching an extreme power output value from the respective optical detector, wherein varying the polarization of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal, without calculating or estimating the exact polarization and / or generating any other signal associated therewith. may include.

[0100] In Example 15, the subject matter of any one or more of Examples 1-14 may include, wherein the method further includes controllably focusing the combined output optical beam using a controllable output beam collimating device.

[0101] Example 16 is a system for coherent beam combining (CBC), comprising: a light source generating a source optical beam; a beam splitting mechanism configured to split a source optical beam into an array of M×N temporally coherent input optical beams and a reference optical beam; - an array of M×N collimating elements configured to direct each of the input optical beams through a separate collimating element to generate M×N output optical beams corresponding to the input optical beams passed through the collimating elements, such that the output optical beams are parallel to one another and define a first propagation direction; a beam splitting element configured to split each of the output optical beams such that a first portion of each of the output optical beams is directed towards a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam, and a second portion of each of the output optical beams is directed towards a second propagation direction and is used as a sample optical beam; - an array of M x N optical detectors, each arranged and configured to measure the overall intensity of a respective optical interference signal, and to output a power output value corresponding to the overall intensity of the respective optical interference signal; a control subsystem configured to continuously receive the measured power output values ​​from each of the optical detectors, vary the phase of each of the input optical beams while comparing the measured power output value of the respective optical interference signal to at least one previously measured power output value from the respective optical detector, and lock the phase of the input optical beam when an extreme power output value of the respective optical interference signal is reached; and Equipped with Varying the phase of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal, without calculating or estimating the exact phase and / or generating any other signal associated therewith; The generation of the optical interference light signal, the measurement of the outputs of the multiple optical detectors, and the phase locking are performed continuously and simultaneously for all M×N input and output optical beams and optical interference signals. It is a system.

[0102] In example 17, the subject matter of example 16 further comprises: M×N phase shifters (PS), each PS configured to change the phase of a different input optical beam; a control module, M×N processing modules (PM), each PM configured to receive a power output value of a different optical detector and iteratively control its associated PS; The method may include providing one or more of the following:

[0103] In example 18, the subject matter of any one or more of examples 16-17, the system further comprising: a reference optical fiber for directing a reference beam, the optical fiber having an input end for receiving light from a light source and an output end from which the reference beam is emitted; a reference beam collimator positioned to collimate the reference optical beam before it interferes with the sample optical beam; It may further include one or more of the following.

[0104] In Example 19, the subject matter of any one or more of Examples 16-18 may further include including a wavefront control mechanism configured to control one or more characteristics of a wavefront of the combined output optical beam.

[0105] In example 20, the subject matter of example 19 further comprises: Far-field (FF) distribution of wavefront, FF position of the central lobe that can be formed by the combined output optical beam; Focusing characteristics of the central lobe, The spatial organization of the wavefront, Environmental Optical Aberration Correction It may include including one or more of the following.

[0106] In Example 21, the subject matter of any one or more of Examples 19 to 20 may include that the wavefront control mechanism is configured to control a relative arrangement between the reference optical fiber output end and the reference beam collimator for steering control of the combined output optical beam.

[0107] In Example 22, the subject matter of any one or more of Examples 19-20 may include the system further including an M×N array of phase control modules (PCMs), each PCM arranged and configured to control the phase of a different portion of the reference optical beam that interferes with a respective sample optical beam.

[0108] In Example 23, the subject matter of Example 22 can include that the M×N array of PCMs is electronically and / or digitally controllable by the control subsystem or a separate controller.

[0109] In Example 24, the subject matter of Example 23 may include where the M×N array of PCMs comprises an M×N array of spatial light modulators (SLMs).

[0110] In Example 25, the subject matter of any one or more of Examples 19-24 can include controlling one or more characteristics of a wavefront of the combined output optical beam according to a target FF position.

[0111] In Example 26, the subject matter of any one or more of Examples 16 to 25 may include that the system may further include M×N polarization controllers (PCs), each PC associated with a different PM and configured to control the polarization of each of the input optical beams based on a received power output value of its respective measured power output value.

[0112] In example 27, the subject matter of example 26 further comprises controlling the polarization of each of the input optical beams by: automatically and separately varying the polarization of each of the input optical beams while comparing the measured power output value of each optical interference signal to at least one previously measured power output value of each optical interference signal; locking the polarization of each respective input optical beam when an extremum power output value of its respective optical interference signal is reached; Including, Varying the polarization of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal, without calculating or estimating the exact polarization and / or generating any other signal associated therewith. This may include:

[0113] In Example 28, the subject matter of any one or more of Examples 16-27 may include, where the system may further include a focusing device configured and arranged to controllably focus the combined output optical beam.

[0114] In Example 29, the subject matter of any one or more of Examples 16-28 may include where the system may further include an array of M×N optical waveguides, each configured to direct a different input optical beam and / or output optical beam therethrough.

[0115] In Example 30, the subject matter of Example 29 can include where the optical waveguide is an optical fiber, a fiber amplifier, or a doped fiber.

[0116] Example 31 is a method for coherent beam combining (CBC), comprising: providing an M×N array of temporally coherent input optical beams; Providing a reference optical beam; generating M×N output optical beams corresponding to the M×N input optical beams, the output optical beams propagating along a first propagation direction; splitting each of the output optical beams such that a first portion of each of the output optical beams is directed toward a first propagation direction and all of the first portions of the output optical beams form a composite output optical beam and a second portion of each of the output optical beams is directed toward a second propagation direction and is used as a sample optical beam; directing a reference optical beam such that the reference optical beam interferes with the sample optical beam to generate a plurality of optical interference signals; each measuring an overall intensity of each optical interference signal of the plurality of optical interference signals; providing a plurality of M×N optical detectors arranged and configured to generate power output values ​​corresponding to an overall intensity of each optical interference signal; automatically and separately varying a phase of each of the input optical beams while comparing the measured power output value of the respective optical interference signal to at least one previously measured power output value generated by a respective optical detector, wherein varying the phase of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal; locking the phase of the input optical beam when the extremum power output value of the respective optical interference signal is reached. Including, The generation of the optical interference light signal, the measurement of the outputs of the multiple optical detectors, and the phase locking are performed continuously and simultaneously for all M×N input and output optical beams and optical interference signals. This is the method.

[0117] Example 32 is a system for coherent beam combining (CBC), comprising: an array of M×N temporally coherent input optical beams; A reference optical beam; and an array of M×N collimating elements configured to direct each of the input optical beams through a separate collimating element to generate M×N output optical beams corresponding to the input optical beams passed through the collimating elements, the output optical beams being parallel to one another and defining a first propagation direction; a beam splitting element configured to split each of the output optical beams such that a first portion of each of the output optical beams is directed toward a first propagation direction, all of the first portions of the output optical beams forming a composite output optical beam, and a second portion of each of the output optical beams is directed toward a second propagation direction and used as a sample optical beam and directed to interfere with the reference optical beam, generating a plurality of optical interference signals; a plurality of optical detectors, each arranged and configured to measure an overall intensity of a respective optical interference signal and to output a power output value corresponding to the overall intensity of the respective optical interference signal; a control subsystem configured to continuously receive the measured power output values ​​from each of the optical detectors, vary the phase of each of the input optical beams while comparing the measured power output value of the respective optical interference signal to at least one previously measured power output value from a respective optical detector, and lock the phase of the input optical beam when an extreme power output value of the respective optical interference signal is reached; Equipped with Varying the phase of each input optical beam is performed directly based on the measured power output value of its respective optical interference signal; The generation of the optical interference light signal, the measurement of the outputs of the multiple optical detectors, and the phase locking are performed continuously and simultaneously for all M×N input and output optical beams and optical interference signals. It is a system.

[0118] While the invention has been described with respect to a limited number of embodiments, these should not be construed as limitations on the scope of the invention, but rather as illustrations of some of the embodiments.

[0119] Any digital computer system, unit, device, module, and / or engine illustrated herein may be configured or otherwise programmed to implement the methods disclosed herein, and as long as the system, module, and / or engine is configured to implement such methods, it falls within the scope and spirit of the present disclosure. When a system, module, and / or engine is programmed to perform a particular function according to computer-readable and executable instructions from a program software that implements the methods disclosed herein, it effectively becomes a computer specifically dedicated to the embodiment of the methods disclosed herein. The methods and / or processes disclosed herein may be implemented as a computer program product, which may be tangibly embodied in an information carrier, including, for example, a non-transitory tangible computer-readable and / or non-transitory tangible machine-readable storage device. The computer program product may be directly loadable into the internal memory of a digital computer and includes software code portions for performing the methods and / or processes as disclosed herein.

[0120] Additionally or alternatively, the methods and / or processes disclosed herein may be implemented as a computer program that may be intangibly embodied by a computer-readable signal medium. A computer-readable signal medium may include a propagated data signal with computer-readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electromagnetic, optical, or any suitable combination thereof. A computer-readable signal medium may be any computer-readable medium that is not a non-transitory computer or machine-readable storage device, but can communicate, propagate, or transport a program used by or in connection with the apparatus, system, platform, method, operation, and / or process discussed herein.

[0121] "Non-transitory computer-readable storage device" and "non-transitory machine-readable storage device" encompass distribution media, intermediate storage media, computer execution memory, and any other medium or device that can be stored for subsequent reading by a computer program that implements an embodiment of the method disclosed herein. A computer program product can be deployed to be executed on one computer or multiple computers, at one location, or distributed across multiple locations and interconnected by one or more communications networks.

[0122] These computer-readable and executable instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to make a machine, such that the instructions executed by the processor of the computer or other programmable data processing apparatus create means for implementing the function / acts specified in the flowchart and / or block diagram block(s). These computer-readable and executable program instructions may also be stored in a computer-readable storage medium that can direct a computer, programmable data processing apparatus, and / or other device to function in a particular manner, such that a computer-readable storage medium having instructions stored therein includes an article of manufacture that includes instructions that implement aspects of the function / acts specified in the flowchart and / or block diagram block(s).

[0123] The computer-readable and executable instructions may also be loaded into a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus, or other device to create a computer-implemented process, such that the instructions executing on the computer, other programmable apparatus, or other device implement aspects of the functions / acts specified in the block(s) of the flowcharts and / or block diagrams.

[0124] The modules, devices, mechanisms, units, and or subsystems may each include machine(s) executable instructions (e.g., commands). The modules may be embodied by circuits or controllers programmed to cause the system to implement the methods, processes, and / or operations as disclosed herein. For example, the modules may be implemented as hardware circuits including, for example, customized very large scale integrated (VLSI) circuits or gate arrays, application specific integrated circuits (ASICs), off-the-shelf semiconductors such as logic chips, transistors, and / or other discrete components. The modules may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices, and the like.

[0125] In the discussion, unless otherwise specified, adjectives such as "substantially" and "about" that modify the state or relationship characteristic of a feature or features of the embodiments of the invention should be understood to mean that the state or characteristic is defined within acceptable tolerances allowed for the operation of the embodiment for its intended use.

[0126] Unless otherwise specified, the terms "substantially," "about," and / or "close to" in reference to a magnitude or value may imply a range of -10% to +10% (inclusive) of the respective magnitude or value.

[0127] It is important to note that what the method may include is not limited to the figures or the corresponding descriptions. For example, the method may include additional or fewer processes or operations compared to those described in the figures. Additionally, the method embodiments are not necessarily limited to the chronological order as shown and described herein.

[0128] For example, discussion herein utilizing terms such as "processing," "computing," "calculating," "determining," "establishing," "analyzing," "checking," "estimating," "deriving," "selecting," "inferring," and the like, may refer to operation(s) and / or process(es) of a computer, computing platform, computing system, or other electronic computing device that manipulates or transforms data represented as physical (e.g., electronic) quantities in the computer's registers and / or memory into other data similarly represented as physical quantities in the computer's registers and / or memory, or other information storage medium that may store instructions for performing the operations and / or processes. The term determining may also refer to "heuristically determining," where applicable.

[0129] It should be noted that when an embodiment refers to a "above threshold" condition, this should not be interpreted as excluding an embodiment referring to a "above threshold" condition. Similarly, when an embodiment refers to a "below threshold" condition, this should not be interpreted as excluding an embodiment referring to a "below threshold" condition. It is clear that if a condition is interpreted as being met when the value of a given parameter is above a threshold, the same condition is considered not to be met when the value of the given parameter is below the given threshold. Conversely, if a condition is interpreted as being met when the value of a given parameter is above a threshold, the same condition is considered not to be met when the value of the given parameter is below (and only below) the given threshold.

[0130] When a claim or specification refers to "a" or "one" element and / or feature, it should be understood that such a reference is not to be construed as indicating that only one of those elements is present. Thus, for example, a reference to "an element" or "at least one element" can also encompass "one or more elements."

[0131] Terms used in the singular form shall include the plural unless expressly stated otherwise or the context clearly indicates otherwise.

[0132] In the description and claims of this application, the verbs "comprise," "include," and "have," as well as their conjugations, are used to indicate that the object(s) of the verb is not necessarily a complete recitation of the components, elements, or parts of the subject(s) of the verb.

[0133] Unless otherwise specified, the use of the term "and / or" between the last two members of a list of selection options indicates that selecting one or more of the listed options is appropriate and practicable. Further, use of the term "and / or" may be used interchangeably with the terms "at least one of," "any one of," or "one or more of," followed by a list of various options.

[0134] It will be understood that certain features of the invention that are described, for clarity, in the context of separate embodiments or examples, may also be provided in combination in a single embodiment. Conversely, for brevity, various features of the invention that are described in the context of a single embodiment, example, and / or option may also be provided separately or in any suitable subcombination, or as suitable with any other described embodiment, example, or option of the invention. Certain features described in the context of various embodiments, examples, and / or optional implementations should not be considered essential features of those embodiments, unless the embodiments, examples, and / or optional implementations would not operate without those elements.

[0135] It should be noted that the terms "in some embodiments," "according to some embodiments," "according to some embodiments of the invention," "for example," "as an example," "for example," and "optionally" can be used interchangeably herein.

[0136] The number of elements shown in the figures should not be construed as limiting in any way but is for illustrative purposes only.

[0137] It should be noted that the term "operable to" can encompass the meaning of the term "modified or configured to." In other words, a machine "operable to" perform a task can include, in some embodiments, the mere ability to perform (e.g., be modified to) a function, and, in some other embodiments, a machine that is actually made (e.g., configured) to perform a function.

[0138] Throughout this application, various embodiments may be presented in and / or associated with a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the embodiments. Thus, the description of a range should be considered to have specifically disclosed all possible subranges and individual numerical values ​​within that range. For example, description of a range such as 1-6 should be considered to have specifically disclosed subranges such as 1-3, 1-4, 1-5, 2-4, 2-6, 3-6, etc., as well as individual numerical values ​​within that range, e.g., 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

[0139] The phrases "ranging between" a first designated number and a second designated number, and "ranging from" a first designated number to a second designated number, are used interchangeably herein and are intended to include the first and second designated numbers, and all fractional and integer numbers therebetween.

Claims

1. 1. A method for coherent beam combining (CBC), comprising: generating an array of temporally coherent input optical beams and a reference optical beam; generating an array of output optical beams corresponding to the array of input optical beams for beam combining, such that the output optical beams propagate along a first propagation direction; splitting each output optical beam such that a first portion of each output optical beam is directed in a first propagation direction, such that all of the first portions of the output optical beams form a composite output optical beam, and a second portion of each output optical beam is directed in a second propagation direction and is used as a sample optical beam; directing a reference optical beam such that the reference optical beam interferes with the sample optical beam to generate a plurality of corresponding optical interference signals; providing an array of optical detectors positioned and configured to each measure an intensity of a respective optical interference signal and generate a power output value indicative of an overall intensity of the respective optical interference signal; automatically and individually varying the polarization of each input optical beam while comparing the measured power output value of the corresponding optical interference signal to at least one previously measured power output value generated by a respective optical detector, the variation in polarization of each input optical beam being performed directly based on the measured power output value of the respective optical interference signal without calculating or estimating the correct polarization and / or generating other signals related thereto; Fixing the polarization of the input optical beam when a maximum power output value of each optical interference signal is reached; Including, The method, wherein generating an optical interference optical signal, measuring power output values ​​of a plurality of optical detectors, and polarization locking are performed continuously and simultaneously for all input and output optical beams and optical interference signals.

2. The method of claim 1 , wherein the alteration of the polarization of each of the input optical beams is performed using an array of polarization controllers (PCs), each PC configured to control the polarization of a different input optical beam.

3. and controllably altering a phase of each of the input optical beams based on the measured power output value of the respective optical interference signal; Control of the phase of each of the input optical beams can be achieved by: automatically and individually varying the phase of each of the input optical beams while comparing the measured power output value of each optical interference signal to at least one previously measured power output value from a respective optical detector; locking the phase of each input optical beam when a maximum power output value from each optical detector is reached; Including, 10. The method of claim 1, wherein the change in phase of each input optical beam is made directly based on the measured total power output value of the respective optical interference signal.

4. The method of claim 3, wherein the variation in phase of each input optical beam is achieved using an array of phase shifters (PS), each PS configured to vary the phase of a respective input optical beam.

5. 10. The method of claim 1, wherein the polarization is controlled and changed for each input optical beam by controllably increasing or decreasing the polarization of each input optical beam by a predetermined and / or controllable polarization shift span.

6. The method of claim 1 , wherein generating the output optical beams is performed using an array of collimating elements for separately collimating each input optical beam.

7. The method of claim 1 , further comprising controlling one or more characteristics of a wavefront of the combined output optical beam.

8. The one or more controllable characteristics of the wavefront of the combined output optical beam may be: The far-field (FF) distribution of the wavefront, a far-field (FF) location of a central lobe that can be formed by the combined output optical beam; Central lobe focusing characteristics; The spatial configuration of the wavefront, Optical aberration correction, The method of claim 7, comprising one or more of the following:

9. The control of one or more wavefront characteristics may include Mechanically moving the output end of the optical waveguide from which the reference optical beam is output; and / or 8. The method of claim 7, wherein the control is performed by mechanically changing the relative position between an output end of an optical waveguide from which the reference optical beam is output and a focusing lens located in the path of the reference optical beam, thereby controlling the direction of the wavefront of the reference optical beam.

10. 8. The method of claim 7, wherein the control of the one or more wavefront characteristics is performed using an array of phase control modules (PCMs), each phase control module (PCM) positioned and configured to control the phase of a different portion of the reference optical beam that interferes with a respective sample optical beam.

11. 1. A system for coherent beam combining (CBC), comprising: a light source generating a source optical beam; a beam splitting mechanism configured to split a source optical beam into an array of temporally coherent input optical beams and a reference optical beam; an array of collimating elements directing each of the input optical beams through a separate collimating element to generate an output optical beam corresponding to the force optical beam such that the output optical beam propagates through a first propagation direction; a beam splitting element that splits each output optical beam such that a first portion of each output optical beam is directed in a first propagation direction, all of the first portions of the output optical beams forming a combined output optical beam, and a second portion of each output optical beam is directed in a second propagation direction and used as a sample optical beam that is directed to interfere with the reference optical beam, thereby forming a corresponding optical interference signal; an array of optical detectors positioned and configured to measure the intensity of each optical interference signal and to output a power output value corresponding to the overall intensity of each optical interference signal; a control subsystem that continuously receives the measured power output values ​​from each of the optical detectors, varies the polarization of each of the input optical beams while comparing the measured power output value of each of the optical interference signals to at least one previously measured power output value from each of the optical detectors, and fixes the polarization of the input optical beam when a maximum power output value of each of the optical interference signals is reached; Equipped with the change in polarization of each input optical beam is made directly based on the measured power output value of the respective optical interference signal, without calculating or estimating the correct polarization and / or generating other signals related thereto; The system, wherein generating the optical interference light signal, measuring the output of the multiple optical detectors, and fixing the polarization are performed continuously and simultaneously for all input and output optical beams and optical interference signals.

12. The control subsystem includes: an array of polarization controllers (PCs), each PC configured to modify the polarization of a different input optical beam; and 12. The system of claim 11, comprising one or more of an array of processing modules (PMs) configured to receive the power output values ​​of the different optical detectors and to iteratively control at least different PCs associated therewith.

13. a reference optical fiber for guiding a reference optical beam, the optical fiber having an input end for receiving light from the light source and an output end from which the reference optical beam exits; and The system of claim 11 , further comprising one or more reference optical beam collimators positioned to collimate the reference optical beam before interfering with the sample optical beam.

14. 12. The system of claim 11, further comprising a wavefront control mechanism configured to control one or more characteristics of a wavefront of the combined output optical beam.

15. 15. The system of claim 14, wherein the wavefront control mechanism is configured to control a relative position between the reference optical fiber output end and the reference beam collimator for steering control of the combined output optical beam.

16. 15. The system of claim 14, further comprising an array of phase control modules (PCMs), each PCM arranged and configured to control the phase of a different portion of the reference optical beam that interferes with a respective sample optical beam.

17. 12. The system of claim 11, further comprising an array of phase shifters (PS), each PS associated with a different input optical beam and configured to control a phase of a respective one of the input optical beams based on a respective measured power output value.

18. Control of the phase of each of the input optical beams can be achieved by: automatically and individually varying a phase of each of the input optical beams while comparing the measured power output value of each respective optical interference signal to at least one previously measured power output value of the respective optical interference signal; locking the phase of each input optical beam when a maximum power output value of the respective optical interference signal is reached; 18. The system of claim 17, wherein the modification of the phase of each input optical beam is performed directly based on the measured power output value of the respective optical interference signal, without calculating or estimating the correct phase and / or without generating any other signal related thereto.

19. a focusing device constructed and arranged to controllably focus the combined output optical beam; and / or an array of optical waveguides, each configured to direct a different input optical beam and / or output optical beam therethrough; The system of claim 11 , wherein the optical waveguide is an optical fiber, a fiber amplifier, and / or a doped fiber.

20. 1. A system for coherent beam combining (CBC), comprising: an array of temporally coherent input optical beams; A reference optical beam; and an array of collimating elements configured to direct each input optical beam through a respective collimating element to generate an array of output optical beams corresponding to the input optical beams passing through the collimating elements, the output optical beams being parallel to one another and defining a first propagation direction; a beam splitting element configured to split each output optical beam such that a first portion of each output optical beam is directed in a first propagation direction, all of the first portions of each output optical beam forming a composite output optical beam, and a second portion of each output optical beam is directed in a second propagation direction and used as a sample optical beam and directed to interfere with the reference optical beam to generate a plurality of optical interference signals; a plurality of optical detectors arranged and configured to each measure an intensity of a respective optical interference signal and to output a power output value corresponding to an overall intensity of the respective optical interference signal; a plurality of optical detectors configured to continuously receive measured power output values ​​from each optical detector, vary the polarization of each input optical beam while comparing the measured power output value of each optical interference signal with at least one previously measured power output value from a respective optical detector, and fix the polarization of the input optical beam when a maximum power output value of the respective optical interference signal is reached; a change in the polarization of each input optical beam is made directly based on the measured power output value of the respective optical interference signal; The system wherein generating the optical interference light signals, measuring the outputs of the multiple optical detectors, and fixing the polarization are performed continuously and simultaneously for all input and output optical beams and optical interference signals.

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