EP4634697A1

EP4634697A1 - Optical steering for illumination of a target

Info

Publication number: EP4634697A1
Application number: EP23902948.1A
Authority: EP
Inventors: Liran Shimshi; Guerman Pasmanik
Original assignee: Israel Aerospace Industries Ltd
Current assignee: Israel Aerospace Industries Ltd
Priority date: 2022-12-15
Filing date: 2023-12-11
Publication date: 2025-10-22
Also published as: WO2024127393A1; IL299165A

Abstract

A system including: an optical steering module configured to receive reflected light, which reflected light includes a portion of a probe light beam reflected from an object, the reflected light including light of a first polarization type, which optical steering module including; a first optical path allowing passage of light of the first polarization type; a second optical path, including an optical steering element, allowing passage of light of a second polarization type; an optical shot generation module optically connected to the optical steering module to receive light from the first optical path and including: a mirror configured to reverse an orientation of light received from the optical steering module, returning the light towards the optical steering module; and a polarization changing element configured to change light of the first polarization type to light of the second polarization type, light returning from the optical shot generation module to the optical steering module passing through the second optical path of the optical steering module; a processor configured to generate control signals for control of the optical steering element, based on a predicted position of the object, to steer light emitted from the second optical path towards the object.

Description

OPTICAL STEERING FOR ILLUMINATION OF A TARGET

RELATED APPLICATION/S

This application related to: Israeli Patent Application No. 297573 (Attorney Ref. 2882885) filed 23 Oct 2022 which claims priority from Israeli Patent Application No. 289368 (Attorney Ref. 2763340) having filing date of 23 Dec 2021 (to which this application is also related). This application is also related to Israeli Patent Application No. 294743 (Attorney Ref. 2836390) filed 13 Jul 2022. The contents of the above applications are all incorporated by reference as if fully set forth herein in their entirety.

TECHNOLOGICAL FIELD

The present disclosure, in some embodiments, thereof, relates to illumination of a target object and, more particularly, but not exclusively, to illumination of a moving target object, using a reflection of light from the target.

BACKGROUND ART

Background art includes US Patent No. US4637725 which discloses “An interferometer in Mach-Zehnder configuration comprises beam splitters (10, 12) and mirrors (11, 13), which divide an optical beam whose wavefront is to be monitored into an information component and a reference component, and which recombine the information and reference components to form an interference pattern that changes dynamically at a spatial light modulator (14) in response to dynamic variations in the atmosphere through which the beam passes. A spatial light filter (15) comprising a plate with a pin-hole aperture is positioned to transmit the reference component of the beam, but with second-order aberrations being removed from the reference component prior to recombination of the information and reference components. The wavefront of the reference component that recombines with the information component is a substantially unaberrated version of the wavefront of the beam whose wavefront is to be monitored. An acousto-optical beam-steering device (20) steers the reference component in real time so as to maintain substantially continuous alignment of a maximum-intensity centroid of the reference component with respect to the pin-hole aperture of the spatial light filter (15).”.

Additional background art includes: Chinese Patent No. CN103293696, US Patent No. US4773732, US Patent No. US5995223, Chinese Patent No. CN102706461, European Patent Application No. EP3236282, US Patent No. US9857159, and German Patent Application No. DE102005027898.

Acknowledgement of the above references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter.

GENERAL DESCRIPTION

Following is a non-exclusive list of some exemplary embodiments of the disclosure. The present disclosure also includes embodiments which include fewer than all the features in an example and embodiments using features from multiple examples, even if not listed below.

Example 1. A system comprising: an optical steering module configured to receive reflected light, which reflected light includes a portion of a probe light beam reflected from an object, said reflected light including light of a first polarization type, which optical steering module comprising; a first optical path allowing passage of light of said first polarization type; a second optical path, including an optical steering element, allowing passage of light of a second polarization type; an optical shot generation module optically connected to said optical steering module to receive light from said first optical path and comprising: a mirror configured to reverse an orientation of light received from said optical steering module, returning the light towards said optical steering module; and a polarization changing element configured to change light of said first polarization type to light of said second polarization type, light returning from said optical shot generation module to said optical steering module passing through said second optical path of said optical steering module; a processor configured to generate control signals for control of said optical steering element, based on a predicted position of said object, to steer light emitted from said second optical path towards said object.

Example 2. The system according to Example 1, said control signals are to steer light emitted from said second optical path towards a desired portion of said object.

Example 3. The system according to Example 2, wherein said reflected light is reflected from a known portion of said object and said desired portion of said object is a different to said known portion of said object.

Example 4. The system according to Example 2, wherein said known portion comprises tip of said object and said desired portion comprises body of said object.

Example 5. The system according to any one of Examples 1-4, wherein said mirror comprises a phase conjugation mirror.

Example 6. The system according to any one of Examples 1-5, wherein said mirror comprises a retroreflector.

Example 7. The system according to Example 6, wherein said retroreflector comprises a cat's eye retroreflector.

Example 8. The system according to any one of Examples 1-7, comprising a probe beam light source configured to illuminate the object with a probe beam of light including light of said first polarization type.

Example 9. The system according to any one of Examples 1-8, wherein said optical steering module comprises a first polarizer and a second polarizer which both direct light of said first polarization type through said first optical path and direct light of said second polarization type through said second optical path.

Example 10. The system according to any one of Examples 1-4, wherein said received light comprises at least one pulse of laser light.

Example 11. The system according to Example 5, wherein said received light comprises a beam having a plurality of pulses of laser light.

Example 12. The system according to any one of Examples 1-11, wherein said steering element comprises an adjustable wedge.

Example 13. The system according to Example 12, wherein said adjustable wedge steers light by movement of one or more portion of said adjustable wedge.

Example 14. The system according to Example 13, wherein said adjustable wedge includes one or more actuator configured to more said one or more portion of said adjustable wedge, wherein said controller is configured to send control signals to said one or more actuator.

Example 15. The system according to Example 13, wherein said adjustable wedge includes material having an index of refraction controlled by an applied electrical field, wherein said controller is configured to control said applied electrical field.

Example 16. The system according to any one of Examples 1-15, wherein said steering element comprises a mirror having adjustable position.

Example 17. The system according to Example 16, wherein comprising one or more actuator configured to adjust said position of said mirror.

Example 18. The system according to Example 17, wherein said controller is configured to send control signals to said one or more actuator to control said position of said mirror.

Example 19. The system according to any one of Examples 1-18, comprising one or more optical amplifier configured to amplify said reflected light to increase a power of said light emitted from said second optical path towards said object.

Example 20. The system according to any one of Examples 1-19, comprising one or more sensor configured to measure said reflected light and produce a sensor measurement signal of said reflected light; and wherein said processor is configured to receive said sensor measurement signal and generate said predicted position using said sensor measurement signal.

Example 21. The system according to any one of Examples 1-20, comprising a spatial filter positioned to receive light from said optical steering module and to provide light to said shot generation module, wherein said spatial filter is configured to remove noise from said reflected light.

Example 22. A method of illuminating an object comprising: receiving reflected light reflected from said object through a first optical path; reversing a direction of said reflected light; directing said reflected light through a second optical path; adjusting a direction of said reversed reflected light, using one or more steering element of said second optical path, said adjusting based on a predicted position of said object to produce target shot light; and emitting said target shot light towards said predicted position of said object. Example 23. The method according to Example 22, wherein said reflected light includes, at least partially, light of a first polarization type; and wherein said directing comprises changing a polarization of said reflected light.

Example 24. The method according to Example 23, wherein said first optical path allows passage of said light of said first polarization type; and wherein said second optical path allows passage of said light of a second polarization type.

Example 25. The method according to Example 23, wherein said first optical path blocks passage of light of a second polarization type; and wherein said second optical path blocks passage of said light of said first polarization type.

Example 26. The method according to any one of Examples 22-25, comprising determining said predicted position of said object by determining one or both of position and trajectory of said object using said received reflected light.

Example 27. The method according to any one of Examples 22-25, wherein said receiving comprises receiving a plurality of pulses of reflected light, each pulse corresponding to a pulse of probe light emitted towards said object.

Example 28. The method according to Example 27, comprising determining said predicted position of said object by determining one or both of position and trajectory of said object using said plurality of pulses of reflected light.

Example 29. The method according to any one of Examples 22-26, comprising emitting probe beam light towards said object.

Example 30. A system comprising: an optical steering module configured to receive reflected light, which reflected light includes a portion of a probe light beam reflected from an object, which optical steering module comprising; a first optical path; a second optical path, including an optical steering element; an optical shot generation module optically connected to said optical steering module to receive light from said first optical path and comprising: a mirror configured to reverse an orientation of light received from said optical steering module, returning the light towards said optical steering module; and a controller configured to control said optical steering element, based on a predicted position of said object, to steer light emitted from said second optical path towards said object.

Unless otherwise defined, all technical and/or scientific terms used within this document have meaning as commonly understood by one of ordinary skill in the art/s to which the present disclosure pertains. Methods and/or materials similar or equivalent to those described herein can be used in the practice and/or testing of embodiments of the present disclosure, and exemplary methods and/or materials are described below. Regarding exemplary embodiments described below, the materials, methods, and examples are illustrative and are not intended to be necessarily limiting.

Some embodiments of the present disclosure are embodied as a system, method, or computer program product. For example, some embodiments of the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro code, etc.) or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module” and/or “system.”

Implementation of the method and/or system of some embodiments of the present disclosure can involve performing and/or completing selected tasks manually, automatically, or a combination thereof. According to actual instrumentation and/or equipment of some embodiments of the method and/or system of the present disclosure, several selected tasks could be implemented by hardware, by software or by firmware and/or by a combination thereof, e.g., using an operating system.

For example, hardware for performing selected tasks according to some embodiments of the present disclosure could be implemented as a chip or a circuit. As software, selected tasks according to some embodiments of the present disclosure could be implemented as a plurality of software instructions being executed by a computational device e.g., using any suitable operating system.

In some embodiments, one or more tasks according to some exemplary embodiments of method and/or system as described herein are performed by a data processor, such as a computing platform for executing a plurality of instructions. Optionally, the data processor includes a volatile memory for storing instructions and/or data and/or a non-volatile storage e.g., for storing instructions and/or data. Optionally, a network connection is provided as well. User interface/s e.g., display/s and/or user input device/s are optionally provided.

Some embodiments of the present disclosure may be described below with reference to flowchart illustrations and/or block diagrams. For example illustrating exemplary methods and/or apparatus (systems) and/or and computer program products according to embodiments of the present disclosure. It will be understood that each step of the flowchart illustrations and/or block of the block diagrams, and/or combinations of steps in the flowchart illustrations and/or blocks in the block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart steps and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer readable medium that can direct a computer (e.g., in a memory, local and/or hosted at the cloud), other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium can be used to produce an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks.

The computer program instructions may also be run by one or more computational device to cause a series of operational steps to be performed e.g., on the computational device, other programmable apparatus and/or other devices to produce a computer implemented process such that the instructions which execute provide processes for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

Some of the methods described herein are generally designed only for use by a computer, and may not be feasible and/or practical for performing purely manually, by a human expert. A human expert who wanted to manually perform similar tasks, might be expected to use different methods, e.g., making use of expert knowledge and/or the pattern recognition capabilities of the human brain, potentially more efficient than manually going through the steps of the methods described herein. BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

FIG. 1 is a simplified schematic of a system for illuminating an object, according to some embodiments of the disclosure;

FIG. 2 is a method of illuminating a target object, according to some embodiments of the disclosure;

FIG. 3 is a method of illuminating a target object, according to some embodiments of the disclosure;

FIGs. 4A-C are simplified schematics of a system for illuminating an object, according to some embodiments of the disclosure;

FIGs. 5A-B are simplified schematics of an optical system, according to some embodiments of the disclosure.

FIG. 6A is a simplified schematics of an optical system 600, according to some embodiments of the disclosure; and

FIG. 6B is a simplified schematic of a filter element, according to some embodiments of the disclosure.

In some embodiments, although non-limiting, in different figures, like numerals are used to refer to like elements, for example, element 126 in FIG. 1 corresponding to element 426 in FIG. 4.

DETAILED DESCRIPTION OF EMBODIMENTS

The present disclosure, in some embodiments, thereof, relates to illumination of a target object and, more particularly, but not exclusively, to illumination of a moving target object.

Overview

A broad aspect of some embodiments of the invention relates to illuminating a target using light reflected from the object by reversing orientation and steering of the reflected light, the steering compensating for movement of the object (e.g., during the time of flight of the reflected light beam from the target to the laser and back to the target) and/or so that a desired portion of the object is illuminated (e.g., the desired portion not being the portion of the object from which the reflected light emanates).

In some embodiments, a wide-angle probe beam e.g., covering a large angular range, yields a reflection of the probe beam from the target object.

In some embodiments, the probe light includes one or more pulses of light having short duration. In some embodiments, the probe light includes a beam having a plurality of time- separated pulses. In this document, the words “light” and/or “beam” and/or “pulse/s” may be used, however, the term, when not otherwise defined, should be understood to include each option e.g., when the term “light” is used, it should be understood to also encompass “beam” and/or “pulse/s”.

In some embodiments, a portion of probe light reflected (herein termed “reflected probe light” or “reflected light”) by the object is used to generate target shot light (also herein termed “target light” and/or “shot light”) directed back towards the object. In some embodiments, the shot light acquires directional properties of a phase conjugated reflection of the reflected probe beam. In some embodiments, the target shot light has smaller divergence than the probe light. In some embodiments, the target shot light includes a beam having a plurality of time- separated (e.g., laser) pulses.

In some embodiments, the target object is moving sufficiently fast that in the time required for the reflected probe beam to arrive at the system, be reversed in direction, and arrive as target shot light at the object, the object has moved. For example, if the target is 6km away from the system, 40ps are required for light to be reflected to the system and then back again to the target, a time in which a target object travelling lOOOm/s travels 40mm.

In some embodiments, the target shot light is steered towards a desired portion of the target object. For example, where reflection of probe light is from a first portion of the target intercepting an optical path of the probe light, where the first portion is not a desired part of the target to receive target shot light. For example, if the target is elongate having an axis of elongation angled towards the system producing the probe light and/or target shot light, the first portion, in some embodiments, is the tip of the target, where, in some embodiments, a central region of the target is to be illuminated by the target shot.

In some embodiments, steering is provided by a steering module having first and second paths. Where, in some embodiments, incoming light is directed into the shot generator module via the first optical path (of the steering module) and outwards towards the object from the shot generator module via the second optical path (of the steering module) which second optical path includes one or more steering element. In some embodiments the first optical path provides a free optical path e.g. (to probe beam reflections) that bypass the steering element.

In an exemplary embodiment, splitting of the optical path to first and second paths is achieved by changing a polarization of the light e.g., at the shot generator module. Where, for example, entrance to the first and second optical paths are through polarizers which direct reflected probe beam light through the first optical path and the reversed reflected probe beam light having a changed polarization (e.g. to be perpendicular) through the second optical path.

For example, in some embodiments, the reflected probe light has a first polarization type and is received by a first polarizer, which first polarizer passes the probe light through the first optical path.

Then the light is reorientated (e.g., by the shot generation module), optionally changed in in polarization (e.g. the polarization is changed to be perpendicular), and optionally amplified (not necessarily in this order) to become target shot light. When the target shot light arrives at a second polarizer which directs the target shot light through a second optical path, where a direction of the target shot light is adjusted to direct, and/or steer, the target shot light to the target and/or a desired region of the target.

In some embodiments, splitting of the optical path into first and second paths is by beam splitters. Where, in an exemplary embodiment, the beam splitters are polarizing beam splitters.

Where, in some embodiments, the steering is based on a predicted position of the target object at the time that the target shot arrives at the target object.

Optionally, in some embodiments, the reflected probe light is also amplified e.g., to provide a target shot beam having higher power than the reflected probe beam.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not necessarily limited in its application to the details of construction and the arrangement of the components and/or methods set forth in the following description and/or illustrated in the drawings and/or the Examples. The invention is capable of other embodiments or of being practiced or carried out in various ways and/or being used in different applications to those described herein. FIG. 1 is a simplified schematic of a system 100 for illuminating an object 110, according to some embodiments of the disclosure.

In FIG. 1, in some embodiments, dashed lines (and/or dashed line arrows) are to be understood as indicating optical paths and solid lined arrows are to be understood as electrical control signal connections.

In some embodiments, object 110 is a stationary and/or static object. In some embodiments, object 110 is a moving object e.g., a ground or sea-borne or air-borne moving object. In some embodiments, object 110 moves e.g. along a trajectory in space . In some embodiments, object 110 moves along a predictable trajectory.

In some embodiments, system includes a probe laser device 115 which, in some embodiments, supplies light for a probe beam 109 emitted towards object 110.

Where, in some embodiments, at least a portion of light of probe beam 109 is reflected from an area 114 of object 110 as a reflected probe beam (RPB) 113 towards system 100.

In some embodiments, system 100 includes one or more sensor 176 which senses object 110. In some embodiments, sensor/s 176 supply measurement signal/s to processing and memory circuitry (PMC) 126. In some embodiments, sensor/s 176 include optical sensor/s (e.g., a camera) which, for example, in some embodiments, measure a portion of reflected probe beam light 113 and/or a position of the reflected probe beam light in in space.

In some embodiments, system 100 receives (e.g. at least a portion of) reflected probe beam (RPB) light 113 at an optical steering module 172 which passes RPB 113 light to shot generation module 130. In some embodiments, shot generation module returns adjusted reflected probe beam (ARPB) light 138 to optical steering module which outputs target shot light 139 towards target 110.

In some embodiments, shot generation module receives light from a pump laser device (not illustrated) and combines this received light with RPB 113 to produce ARPB 138.

In some embodiments, PMC 126 receives information regarding target 110, for example, from sensor/s 176. In some embodiments, PMC 126 determines a trajectory (e.g. predicted trajectory) of target 110 e.g. using the information received.

For example, in some embodiments, sensor/s 176 provide a series of measurements over time of target 110 as it moves, the measurements providing past position and trajectory, which position and trajectory are used to estimate a future position of the target and/or of a portion of the target.

Alternatively or additionally, in some embodiments, PMC 126 receives data regarding a trajectory e.g. a trajectory sensed and/or determined externally to system 100.

Alternatively or additionally, in some embodiments, system 100 includes (and/or is operatively coupled with) one or more devices 150 (e.g., including one or more sensor/s) for tracking and/or engaging with object 110. For example, enabling one or more of engagement with object 110 and/or detection of the object 110 and/or acquisition of the object 110. Where, in some embodiments, devices 150 include one or more RADAR (radio detection and ranging circuitry) and/or Forward-looking infrared (FLIR) camera/s and/or a visible camera/s.

In some embodiments, system 100 includes processing and/or memory circuitry PMC 126. Where PMC 126, in some embodiments, communicates with one or more other components of system 100. For example, receiving signal/s from and/or sending control signals to one or more of optical steering module 172, shot generation module 130, and sensors 150.

In some embodiments, e.g., as described in more detail hereinbelow, PMC 126 controls timing of one or more components of system 100. For example, timing of movement of actuators effecting steering of light (e.g. as described regarding actuator/s 570, 571 FIGs. 5A-B).

In some embodiments, system 100 emits (e.g., at different times) probe beams which have different optical emission points from system 100 (e.g., from probe laser device 115).

Optionally, in some embodiments light entering and/or being emitted from system 100 passes through additional optical element/s which are not illustrated in FIG. 1 (e.g., prior to entry or exit from system 100). Where, the additional optical elements, in some embodiments, include one or more mirrors, and/or telescopes, and/or lenses and/or optical- amplifiers .

FIG. 2 is a method of illuminating a target object, according to some embodiments of the disclosure.

At 200, in some embodiments, a broad probe beam is emitted. Where, in some embodiments, the broad probe beam has a divergence of more than 2 milliradians, or of more than 10 milliradians, or lower or higher or intermediate divergences. For example, by an optical system e.g., probe beam 109 system 100 FIG. 1 e.g., probe beam 409 system 400 FIG. 4A.

Where, in some embodiments, the probe beam is emitted towards a general region of space e.g., in which a target is located and/or which is being monitored for presence of target/s.

In some embodiments, the probe light includes a probe beam having one or more time- separated pulses. Where, in some embodiments, the pulses have a duration of 0.1 - 10ns, or lower or higher or intermediate durations or ranges. In some embodiments, the probe beam includes laser light Where, in some embodiments, a wavelength of the probe beam light is 1000 to 1700 nm or e.g., about 1.06 microns wavelength, or lower or higher or intermediate wavelengths or ranges.

At 202, in some embodiments, at least a portion of the probe beam is reflected, as a reflected probe beam (e.g., reflected probe beam 113 FIG. 1, e.g., reflected probe beam 413 FIG. 4B, e.g., reflected probe beam 513 FIG. 5B), by a target object (e.g., target object 110 FIG. 1, e.g., target object 410 FIG. 4B).

At 204, in some embodiments, a target shot beam (e.g., target shot beam 139 FIG. 1, e.g., target shot beam 439 FIG. 4C, e.g., target shot beam 539 FIG. 5C) is generated using the received reflected probe beam. In some embodiments, the shot beam is emitted towards the target.

At 206, in some embodiments, the target shot beam is directed towards the target. Directing, for example, performed by an optical steering module e.g. as described and/or illustrated regarding optical steering module 172 FIG. 1 and/or optical steering module 472 FIGs. 4A-B, and/or optical steering module 572 FIGs. 5A-B.

FIG. 3 is a method of illuminating a target object, according to some embodiments of the disclosure.

At 300, in some embodiments, a reflection of probe light is received. The receiving, in some embodiments, including one or more feature as described with respect to step 202, FIG. 2. In some embodiments, a plurality of temporally separated light pulses are received, each pulse corresponding to a probe beam illumination pulse

At 301, optionally, information regarding a target is received and/or determined. In some embodiments, sensor measurement/s are received. For example, in some embodiments, measurement including optical measurement of a portion of received reflected probe light.

For example, in some embodiments, position and/or trajectory of the target is determined using the received reflected probe light e.g. for a plurality of probe light pulses.

For example, a known time of emission of probe light and a time taken for reflected probe light to be sensed at system sensor/s, in some embodiments, is used to determine a distance between the sensor/s and the target.

For example, a known direction of probe light being used to determine a position of the target.

Alternatively or additionally, in some embodiments, the received sensor measurement/s include optical sensor (e.g. camera) measurement of the target. In some embodiments, the received sensor measurement/s include radar measurement of the target. In some embodiments, the sensor measurement/s are used to determine position and/or trajectory of a target and/or used to predict a future position of the target. At 302, in some embodiments a shot beam is generated. Generating including, for example, one or more of steps 304-308:

At 304, in some embodiments, direction of received reflection of probe light is reversed, for example, by a mirror (e.g., mirror element 511 FIG. 5) for example, a phase conjugating mirror.

At 306, optionally, in some embodiments, the received light is amplified.

At 308, optionally, in some embodiments, polarization of received light is changed.

At 310, in some embodiments, direction of received light is adjusted. For example, based on information regarding the target e.g. received and/or determined at step 301. For example, based on a received and/or determined position (or predicted future position) of the object and/or portion of the object to be illuminated.

For example, in some embodiments, a required change in direction due to movement of the target is determined using received and/or generated trajectory prediction data for the object and information regarding time of flight from and/or to the object. Where, in some embodiments, target shot light has an address including two parameters, a time parameter corresponding to an elapsed time from the first target reflection acquisition and a directional parameter corresponding to a directional vector to the target. Where, in some embodiments, each pulse of a beam of target shot pulses includes an individual time and directional parameters.

In some embodiments, adjusting of the direction is by one or more steering element controlled by a controller.

In some embodiments, change of polarization of the light at step 308 enables interaction of the light with steering element/s e.g., as the different polarizations (e.g., two perpendicular polarizations) of light are directed along a different paths e.g., as described regarding polarization changing element/s 591 and/or optical steering module 572 FIGs. 5A-B.

In some embodiments, steps 304-310 are in a different order than described above.

At 312, in some embodiments, the generated shot beam, which in some embodiments, includes one or more pulses of light (e.g., laser light) is emitted.

FIGs. 4A-C are simplified schematic of a system 400 for illuminating an object 410, according to some embodiments of the disclosure.

FIGs. 4A-C in some embodiments, illustrate light paths within system 400 over a time period.

In some embodiments, system 400 includes one or more feature illustrated in and/or described regarding system 100 FIG. 1.

In some embodiments, system 400 includes a probe laser device 415 which, in some embodiments, includes one or more feature as illustrated and/or described regarding probe laser device 115 FIG. 1.

In some embodiments, probe laser device 415 includes a light source for a probe beam 409 (which, in some embodiments, includes one or more feature as illustrated and/or described regarding probe beam 109 FIG. 1).

In some embodiments, FIG. 4A illustrates a cross sectional view of probe beam 409. Where, in some embodiments, a central axis of probe beam 409 is illustrated by arrow 419. In some embodiments, system 400 includes an optical steering module 472 which, in some embodiments, includes one or more feature as illustrated in and/or described regarding optical steering module 172 FIG. 1.

In some embodiments, system 400 includes a PMC 426 which, in some embodiments, includes one or more feature as illustrated in and/or described regarding PMC 126 FIG. 1.

In some embodiments, system 400 includes a shot generation module 430 which, in some embodiments, includes one or more feature as illustrated in and/or described regarding shot generation module 130 FIG. 1.

In some embodiments, system 400 includes one or more sensor/s 476 which, in some embodiments, include one or more feature as illustrated in and/or described regarding sensor/s 176 FIG. 1

Referring now specifically to FIG. 4A which, in some embodiments, illustrates a time period where probe laser device 415 emits probe beam 409 e.g., towards target 410.

Referring now to FIG. 4B, which, in some embodiments, illustrates a time period after illumination of object 410 with a pulse probe beam 409, illustrating a path of reflected probe beam (RPB) light 413 from a region 414 of target towards optical steering module 472.

Optionally, in some embodiments, a portion 413a of RPB light 413 (the portion 413a being, for example 5% or less, or 1% or less of a total power of the RPB light 413 received by system 400) is directed (e.g. by a splitter 490) to optical sensor/s 476. Where, in some embodiments, optical sensor/s 476 provide sensor measurement signal/s to PCM 426.

Where, in some embodiments, at least a portion of reflected probe beam light 413b passes through optical steering module 472 to shot generation module 430.

In some embodiments, target 410 is moving e.g., in a direction illustrated by arrow 474.

Referring now to FIG. 4C, which, in some embodiments, illustrates a time period after that illustrated in FIG. 4B, where shot generation module 430, in some embodiments, generates a beam 478 using light received from optical steering module 472, the generated beam 478 then passing through optical steering module 472 to be emitted as a target shot beam 439. In some embodiments, shot generation module 430 couples amplified light (e.g. from a pulsed laser source) with light 413b (e.g. a phase conjugated reflection of light) received from optical steering module 472 to produce light 478 which, once passed through optical steering module 472 becomes target shot beam 439.

Where, in some embodiments, target shot beam 439 is directed towards target 410 e.g., to a specific portion 414 of target 410. Where, in some embodiments, the specific portion 414 of target is a same portion of the target from which the probe beam was reflected. Where, in some embodiments, the specific portion 414 of target 410 is a different portion of the target that the portion from which the probe beam was reflected. For example, in some embodiments, a tip and/or portion of the target closest to system 400 and/or closest to probe laser device 415 reflects the probe beam, and the shot beam 439 is directed to a body 417 of object 410.

Where, in some embodiments, FIG. 4C illustrates an embodiment where target 410 has moved from the position illustrated in FIG. 4B (and illustrated by dashed lines and numeral 610 in FIG. 4C) to the position of target object 410 illustrated in FIG. 4C.

Optionally, in some embodiments, shot generation module 430 includes one or more amplifiers. In some embodiments, amplification at the shot generation module includes receiving light from a pump laser device (not illustrated), which in some embodiments, is controlled by PCM. In some embodiments, light 478 from shot generation module passes to optical steering module 472 before being emitted as target shot beam 439.

FIGs. 5A-B are simplified schematics of an optical system 500, according to some embodiments of the disclosure.

In some embodiments, optical system 500 includes an optical steering module 572. In some embodiments, optical steering module 572 illustrates an exemplary implementation of one or more of optical steering module 172 FIG. 1 and optical steering module 472 FIGs. 4A-B.

In some embodiments, system 500 includes a shot generation module 530 which, in some embodiments, includes one or more feature of shot generation module 130 FIG. 1 and/or shot generation module 430 FIGs. 4A-C. In some embodiments, FIGs. 5A-B illustrate a subset of system 500 elements. For example, where system 500 includes one or more additional feature e.g., as illustrated and/or described regarding system 100 FIG. 1 and/or system 400 FIGs. 4A-C.

In some embodiments, FIGs. 5A-B illustrate light paths at different times (e.g., sequentially) with respect to optical steering module 572.

In some embodiments, optical steering module 572 includes a plurality of beam splitters 560, 564.

In some embodiments, beam splitters are polarizing beam splitters 560, 564 which direct light of different polarizations in different directions.

In some embodiments, one or both of splitters 560, 564 include semi-transparent mirrors and/or beam splitters and/or optical filters (for example, as an alternative to polarizing beam splitters).

Although discussion below is regarding an embodiment of system 500 where beam splitters 560, 564 are polarizing beam splitters, it should be understood that, in some embodiments, other type/s of beam splitter are used, in which case, in some embodiments, system lacks a polarization changing element 591.

Where, in some embodiments, polarizing beam splitters 560, 564 provide two optical paths for orthogonal polarizations. In some embodiments, optical steering module 572 includes a plurality of mirrors 562, 566.

In some embodiments, for each of the polarizers 560, 564 light of a first polarization type is directed through a lower arm 501 (also herein termed “first optical path” through optical steering module 572) of optical steering module 572 to the other polarizer; e.g., first polarizer 560 directing first polarization type light through the lower arm to second polarizer 564 e.g., second polarizer 564 directing first polarization type through the lower arm to first polarizer 560. Where, for example, in some embodiments, the first polarization type is s-polarized light and the second polarization type is p- polarized (or vice versa).

Similarly, in some embodiments, polarizing beam splitters 560, 564 each direct light of a second polarization type through an upper arm 502 (also herein termed “second optical path” through optical steering module 572) of optical steering module 572 to the other polarizer; e.g., first polarizing beam splitter 560 directing second polarization type light through the upper arm to second polarizer 564.

In some embodiments, each lower and upper arms include mirrors 562, 566. In some embodiments, second optical path (upper arm) 502 includes at least one beam steering optical element. In some embodiments, steering is performed rapidly sufficiently fast for reflected probe beam light to be directed to the object.

For example, as illustrated in FIGs. 5A-C, the upper arm includes a pair of an adjustable wedges 568, adjustment of adjustable wedges 568, in some embodiments, by actuator/s 571 and/or actuator/s 570 for adjustment of element 566.

In some embodiments, optical steering module 572 includes an adjustable pair of wedges 568. Where one or both of position (e.g., where the wedge is moved by one or more actuator 571 controlled e.g., by controller 526) of the wedge and angle of refraction by the wedge are adjustable.

Where, in some embodiments, adjustable wedge 568 includes a liquid-filled adjustable optical wedge where, angle of refraction of the wedge is changed by a physical angle of the wedge, where adjustability of the angle of the optical wedge is by movement of bounding surfaces of the liquid. For example where, in some embodiments, a liquid- filled variable angle prism includes two flat optical plates separated by optical fluid. Where angle of the plates (e.g., movement of the plates by one or more actuator controlled by PCM 526) is adjusted to change dimensions of the optical fluid wedge between the plates.

In some embodiments, to avoid (and/or reduce) wavefront distortion the liquid layer is thin. In some embodiments, the optical fluid has a refractive index matching the refractive index of plates.

In some embodiments, adjustable wedge 568 includes one or more feature as described and/or illustrated in: Iwasinska-Kowalska, O. (2016). Liquid-filled adjustable optical wedge applied for deflection of the laser beam. In: Jablonski, R., Brezina, T. (eds) Advanced Mechatronics Solutions. Advances in Intelligent Systems and Computing, vol 393. Springer, Cham, which is herein incorporated by reference in its entirety.

Where, in some embodiments, adjustable wedge 568 includes a wedge comprising material which changes index of refraction under an electrical field where, for example, steering by the adjustable wedge is achieved by controlling (e.g., by PCM 526) a voltage applied to the wedge. Exemplary materials including liquid crystals and/or crystalline material which displays piezoelectric properties.

Alternatively or additionally to steering via adjustment of adjustable wedge 568, in some embodiments, second optical path 502 includes one or more Risley prisms (not illustrated). For example, each Risley prism including a pair of wedge prisms orientation of which is controlled (e.g., via control of actuator/s) to steer a beam passing through the Risley prism. Potential advantages of Risley prisms as steering elements include one or more of compact size, conformal aperture, low moment of inertia, wide field of regard, and relative immunity to vibration.

Alternatively or additionally to other steering elements described hereinabove, in some embodiments, second optical path includes one or more pair of rotatable diffractive elements, where rotation of the diffractive elements is controlled to steer light passing through second optical path 502.

Alternatively or additionally to other steering elements described hereinabove, in some embodiments, element 566 is configured to be moveable and/or orientable to change direction of light interacting with the element. In some embodiments, movement of element 566 which, in some embodiments, includes a mirror, is effected by one or more actuators 570 e.g., receiving control signal/s from PMC 526.

In some embodiments, actuator/s 570, 571 include one or more piezo-electric actuators.

In an exemplary embodiment, actuator/s 570 include two piezo-electric actuator each actuator configured to rotate mirror 566 about a different axis (where, the axes in some embodiments, are orthogonal). In some embodiments, movement of mirror 556 is small, for example, by l-500nm, or lower or higher or intermediate distances or ranges.

FIGs. 5A-B, in some embodiments, illustrate light paths within system 500 over a time period (e.g., where FIGs. 5A-B in some embodiments, illustrate light paths sequentially with time).

Referring now to FIG. 5A, a reflected probe beam (RPB) 513 (e.g., RPB 413b FIG. 4B, RPB 113 FIG. 1) is received at first polarizer 560 which directs reflected probe beam 513 into the lower arm of optical steering module 572, the reflected probe beam 513 having first polarization type (e.g., a same polarization as probe beam 509). In some embodiments, the probe beam reflected by the object (e.g. see probe beam and object FIG. 1) also herein termed “reflected probe beam” 513 is directed to mirror 562 by polarizer 560 and then by mirror 562 to second polarizer 564 which, in some embodiments, directs reflected probe beam 513 to shot generation module 530. In some embodiments, shot generation module 530 includes a reflective element

511.

In some embodiments, reflective element 511 includes a phase conjugating mirror. Principles and examples of phase conjugating mirrors (also herein termed “phase conjugate mirror” are described e.g., in “Stimulated Brillouin Review: Invented 50 Years Ago and Applied Today”, Elsa Garmire. Content of this document is incorporated herein by reference in its entirety.

Alternatively or additionally, reflective element 511 includes one or more mirror and/or retroreflector.

In some embodiments, shot generation module 530 includes one or more polarization changing element/s 591. Where, in some embodiments, the light passes through the polarization changing elements 591 twice, a first time as the light travels to reflective element 511 from steering module 572, and a second time returning from reflective element to steering module 572. In some embodiments, polarization changing element/s 591 includes a Faraday rotator.

In some embodiments, shot generation module includes an inwards path from steering module towards reflective element 511 and an outwards path from reflective element 511 towards steering module. Where, in some embodiments, each path of the shot generation module includes one or more polarization changing element. Where, for example, one of the paths includes a half wave plate.

In some embodiments, passage of the light through shot generation module 530 changes polarization of reflected probe beam 513 to light including a second polarization type 538.

Where, adjusted reflected probe beam light (ARPB) 538, having second polarization type light, in some embodiments, arriving at optical steering module 572 e.g., to second polarizer 564 is directed, virtue of the polarization of ARPB 538 through the upper arm of optical steering module 572. ARPB 538, in some embodiments, via one or more optical element 566, 568, ARPB passes to first polarizer 560, and from first polarizer (e.g., virtue of second polarization type of ARPB 538) outwards from optical steering module 572 as a shot beam 539.

In some embodiments, one or more optical steering elements 568, 566 are controlled to change a direction of shot beam 539 emitted e.g., to direct shot beam 539 to a target and/or a desired portion of a target (e.g., as described regarding target 110 FIG.1 and/or target 410 FIG. 4C ). Where, in some embodiments, one or more optical steering elements (e.g., elements 566, 558) are controlled by PMC 526.

Optionally, in some embodiments, shot generation module 530 includes one or more optical amplifier (not illustrated). In some embodiments, the optical amplifier/s include a plurality of amplifiers arranged in series, or in parallel, or both in series and in parallel. Exemplary amplifiers include one or more Nd:YAG rod amplifiers (e.g., flash lamp or diode pumped amplifiers) and/or laser pumped Brillouin amplifiers.

Optionally, in some embodiments, shot generation module 530 includes one or more Pockels’ cells and/or Faraday rotators (not illustrated) e.g., acting as isolators for suppression of photon noise.

FIG. 6A is a simplified schematics of an optical system 600, according to some embodiments of the disclosure.

In some embodiments, system 600 includes an optical steering module 672 having one or more features as described and/or illustrated regarding optical steering module 572 FIGs. 5A-B. For example, beam splitters 660, 664, corresponding to beam splitters 560, 564. For example, mirrors 662, 666, corresponding to mirrors 562, 566. For example, beam steering optical element/s 668, and/or 671, and/or 670 and/or 666 corresponding to 568, 571, 570, and 566.

In some embodiments, system 600 includes a shot generation module 630 which, in some embodiments, includes one or more features as described and/or illustrated regarding shot generation module 530 FIGs. 5A-B.

In some embodiments, system 600 includes one or more filters 680. Where, in some embodiments filter/s 680 which reduce or remove noise from light passing from steering module 672 to shot generation module 630.

FIG. 6A, in some embodiments, illustrates noise associated with light received by steering module 672 including both a portion having a first polarization type (solid arrows) and a noise portion having a second polarization type (dotted arrows).

Where, in some embodiments, the “noise” light having second polarization type flows through an upper arm 602 (corresponding to second arm 502 FIGs. 5A-B) of steering module 672 and meets reflected light 613 which has passed through a lower arm 601 (corresponding to lower arm 501 FIGs. 5A-B) to be directed towards shot generation module. 630 In some embodiments, system 600 includes one or more filter 680 configured to remove and/or reduce noise from light passing from the steering module 672 to shot generation module 630. Where an exemplary implementation of filter 680 is illustrated in FIG. 6B.

FIG. 6B is a simplified schematic of a filter element 680, according to some embodiments of the disclosure.

In some embodiments, filter element 680 includes a spatial filter 686. In some embodiments, filter element 680 includes one or more lenses 682, 690. Where, in some embodiments, each lens focuses the light at an aperture, for example at an aperture to the filter element and/or an aperture at the spatial filter.

In some embodiments, spatial filter 680 removes polarization and/or scattering noise from light 613.

In some embodiments, filter element 680, upon receiving light 613 having a mix of polarizations (and/or directions) 684, 688 removes or reduces light 684 from the light received, allowing light e.g. having a first polarization 688, to pass through filter element 680.

A potential benefit of removing such noise light from the signal before the light reaches a shot generation module (e.g. shot generation module 630) is that amplification within the shot generation module with then fail to amplify undesired noise light.

General

As used within this document, the term “about” refers to±20%

The terms “comprises”, “comprising”, “includes”, “including”, “having” and their conjugates mean “including but not limited to”.

The term “consisting of’ means “including and limited to”.

As used herein, singular forms, for example, “a”, “an” and “the” include plural references unless the context clearly dictates otherwise.

Within this application, various quantifications and/or expressions may include use of ranges. Range format should not be construed as an inflexible limitation on the scope of the present disclosure. Accordingly, descriptions including ranges should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within the stated range and/or subrange, for example, 1, 2, 3, 4, 5, and 6. Whenever a numerical range is indicated within this document, it is meant to include any cited numeral (fractional or integral) within the indicated range.

It is appreciated that certain features which are (e.g., for clarity) described in the context of separate embodiments, may also be provided in combination in a single embodiment. Where various features of the present disclosure, which are (e.g., for brevity) described in a context of a single embodiment, may also be provided separately or in any suitable sub-combination or may be suitable for use with any other described embodiment. Features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

Although the present disclosure has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, this application intends to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

All references (e.g., publications, patents, patent applications) mentioned in this specification are herein incorporated in their entirety by reference into the specification, e.g., as if each individual publication, patent, or patent application was individually indicated to be incorporated herein by reference. Citation or identification of any reference in this application should not be construed as an admission that such reference is available as prior art to the present disclosure. In addition, any priority document(s) and/or documents related to this application (e.g., co-filed) are hereby incorporated herein by reference in its/their entirety.

Where section headings are used in this document, they should not be interpreted as necessarily limiting.

Claims

CLAIMS:

1. A system comprising: an optical steering module configured to receive reflected light, which reflected light includes a portion of a probe light beam reflected from an object, said reflected light including light of a first polarization type, which optical steering module comprising; a first optical path allowing passage of light of said first polarization type; a second optical path, including an optical steering element, allowing passage of light of a second polarization type; an optical shot generation module optically connected to said optical steering module to receive light from said first optical path and comprising: a mirror configured to reverse an orientation of light received from said optical steering module, returning the light towards said optical steering module; and a polarization changing element configured to change light of said first polarization type to light of said second polarization type, light returning from said optical shot generation module to said optical steering module passing through said second optical path of said optical steering module; a processor configured to generate control signals for control of said optical steering element, based on a predicted position of said object, to steer light emitted from said second optical path towards said object.

2. The system according to claim 1, said control signals are to steer light emitted from said second optical path towards a desired portion of said object.

3. The system according to claim 2, wherein said reflected light is reflected from a known portion of said object and said desired portion of said object is a different to said known portion of said object.

4. The system according to claim 2, wherein said known portion comprises tip of said object and said desired portion comprises body of said object.

5. The system according to any one of claims 1-4, wherein said mirror comprises a phase conjugation mirror.

6. The system according to any one of claims 1-5, wherein said mirror comprises a retroreflector.

7. The system according to claim 6, wherein said retroreflector comprises a cat's eye retroreflector.

8. The system according to any one of claims 1-7, comprising a probe beam light source configured to illuminate the object with a probe beam of light including light of said first polarization type.

9. The system according to any one of claims 1-8, wherein said optical steering module comprises a first polarizer and a second polarizer which both direct light of said first polarization type through said first optical path and direct light of said second polarization type through said second optical path.

10. The system according to any one of claims 1-4, wherein said received light comprises at least one pulse of laser light.

11. The system according to claim 5, wherein said received light comprises a beam having a plurality of pulses of laser light.

12. The system according to any one of claims 1-11, wherein said steering element comprises an adjustable wedge.

13. The system according to claim 12, wherein said adjustable wedge steers light by movement of one or more portion of said adjustable wedge.

14. The system according to claim 13, wherein said adjustable wedge includes one or more actuator configured to more said one or more portion of said adjustable wedge, wherein said controller is configured to send control signals to said one or more actuator.

15. The system according to claim 13, wherein said adjustable wedge includes material having an index of refraction controlled by an applied electrical field, wherein said controller is configured to control said applied electrical field.

16. The system according to any one of claims 1-15, wherein said steering element comprises a mirror having adjustable position.

17. The system according to claim 16, wherein comprising one or more actuator configured to adjust said position of said mirror.

18. The system according to claim 17, wherein said controller is configured to send control signals to said one or more actuator to control said position of said mirror.

19. The system according to any one of claims 1-18, comprising one or more optical amplifier configured to amplify said reflected light to increase a power of said light emitted from said second optical path towards said object.

20. The system according to any one of claims 1-19, comprising one or more sensor configured to measure said reflected light and produce a sensor measurement signal of said reflected light; and wherein said processor is configured to receive said sensor measurement signal and generate said predicted position using said sensor measurement signal.

21. The system according to any one of claims 1-20, comprising a spatial filter positioned to receive light from said optical steering module and to provide light to said shot generation module, wherein said spatial filter is configured to remove noise from said reflected light.

22. A method of illuminating an object comprising: receiving reflected light reflected from said object through a first optical path; reversing a direction of said reflected light; directing said reflected light through a second optical path; adjusting a direction of said reversed reflected light, using one or more steering element of said second optical path, said adjusting based on a predicted position of said object to produce target shot light; and emitting said target shot light towards said predicted position of said object.

23. The method according to claim 22, wherein said reflected light includes, at least partially, light of a first polarization type; and wherein said directing comprises changing a polarization of said reflected light.

24. The method according to claim 23, wherein said first optical path allows passage of said light of said first polarization type; and wherein said second optical path allows passage of said light of a second polarization type.

25. The method according to claim 23, wherein said first optical path blocks passage of light of a second polarization type; and wherein said second optical path blocks passage of said light of said first polarization type.

26. The method according to any one of claims 22-25, comprising determining said predicted position of said object by determining one or both of position and trajectory of said object using said received reflected light.

27. The method according to any one of claims 22-25, wherein said receiving comprises receiving a plurality of pulses of reflected light, each pulse corresponding to a pulse of probe light emitted towards said object.

28. The method according to claim 27, comprising determining said predicted position of said object by determining one or both of position and trajectory of said object using said plurality of pulses of reflected light.

29. The method according to any one of claims 22-26, comprising emitting probe beam light towards said object.

30. A system comprising: an optical steering module configured to receive reflected light, which reflected light includes a portion of a probe light beam reflected from an object, which optical steering module comprising; a first optical path; a second optical path, including an optical steering element; an optical shot generation module optically connected to said optical steering module to receive light from said first optical path and comprising: a mirror configured to reverse an orientation of light received from said optical steering module, returning the light towards said optical steering module; and a controller configured to control said optical steering element, based on a predicted position of said object, to steer light emitted from said second optical path towards said object.