Beam control for optical beams

Abstract

To allow a beam profile of an optical beam to be changed in accordance with a system using the beam.SOLUTION: In some implementations, an optical device may include a first optical element, or a first prism. The optical device may include a second optical element, or a second prism, and is configured to receive a beam and output the beam. The first optical element and the second optical element may be configured to alter a beam shape of the beam, such that the beam has a first shape at a first location and a second shape at a second location.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 511,475, entitled "PRISM FOR OPTICAL COMPONENT COUPLING," filed June 30, 2023. The disclosure of the prior application is considered a part of this patent application and is incorporated by reference into this patent application.

[0002] FIELD OF THE DISCLOSURE This disclosure relates generally to optical devices and optical devices for controlling light beams. [Background technology]

[0003] The beam profile (contour) of a light beam has a large impact on the system performance of the system using the beam. For example, a light beam having an annular beam profile or annular beam can enable superior cutting performance of a manufacturing system. However, the beam profile of most fiber-delivered light beams is relatively simple. For example, the beam parameters may be a Gaussian or near-Gaussian profile for low beam-parameter-product (BPP) lasers (e.g., BPP less than or equal to about 3 millimeter-millar (mm-mrad)) that can be used to process thin sheet metals (e.g., sheet metals with thicknesses less than or equal to about 3 mm) with tightly converging beams. As another example, the beam profile may be a top-hat (sometimes referred to as flat-top) profile for high BPP lasers (e.g., BPP of about 3 mm-mrad or greater) that can be used to process thick sheet metals with larger beams. Summary of the Invention

[0004] In some embodiments, the optical device includes a first optical element, which is a first prism, and a second optical element, which is a second prism, the optical device configured to receive and output a beam, and the first optical element and the second optical element configured to modify the beam shape of the beam such that the beam has a first shape at a first position and a second shape at a second position.

[0005] In some embodiments, the optical system includes a collimating lens for collimating the beam, a focusing lens for focusing the beam, and an optical device for shaping the beam, the optical device being disposed between the collimating lens and the focusing lens, the optical device comprising a first pyramidal prism and a second pyramidal prism, the first pyramidal prism and the second pyramidal prism being disposed such that the beam has a first beam shape in a near field and a second beam shape in a far field.

[0006] In some embodiments, the method includes setting, by a controller, a relative position of a first optical element and a second optical element in an optical device in an optical system to a first relative position, where the first optical element and the second optical element are a pair of pyramidal prisms, and the optical system is configured to output a first beam shape with the relative position set to the first relative position; and adjusting, by a controller, the relative position of the first optical element and the second optical element in the optical device in the optical system to a second relative position, where the optical system is configured to output a beam having a second beam shape with the relative position set to the second relative position. [Brief description of the drawings]

[0007] [Figure 1A] FIG. 2 is a diagram of an embodiment relating to beam control of a light beam. [Figure 1B] FIG. 2 is a diagram of an embodiment relating to beam control of a light beam. [Figure 2A]FIG. 2 is a diagram of an embodiment relating to beam control of a light beam. [Figure 2B] FIG. 2 is a diagram of an embodiment relating to beam control of a light beam. [Diagram 3] 4 is a flow chart of an example process associated with beam control of a light beam. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The detailed description of the embodiments hereinafter refers to the accompanying drawings, in which the same reference numbers in different drawings may indicate the same or similar elements, and in which:

[0009] An optical system may include optical devices such as optical emitters, process cables, optical elements (e.g., lenses, filters, or mirrors, among other examples) to emit a beam with specific optical characteristics. Examples of such optical systems include communication systems, measurement systems, detection systems, manufacturing systems, ranging systems, or three-dimensional (3D) gesture detection systems, among other examples. Different types of optical systems or use cases of optical systems may be associated with different desired optical characteristics. For example, in an optical communication system, it may be desirable to have a beam that can maintain a center wavelength with high precision and can be modulated to convey information at a high throughput rate. As another example, in an optical manufacturing system, it may be desirable to have a beam that maintains a consistent energy level, has a specific beam shape, and / or is energy efficient.

[0010] Different optical elements can be used to obtain different optical characteristics. For example, an optical coupler including a lens may be disposed between the optical emitter and the process cable to form a beam that is output from the process cable. In other words, the optical emitter may emit a beam toward the optical coupler. The optical coupler may direct the beam to an input of the process cable through which the beam may propagate to an output of the process cable. The output of the process cable may direct the beam to a target, such as, for example, in a manufacturing context, an object to be cut, etched, brazed, clad, hardened, or welded, etc.

[0011] In such configurations, some techniques can vary the beam profile based at least in part on whether the beam is directed on-axis (e.g., toward the center of the process cable at an angle less than the threshold, resulting in less than threshold reflections within the process cable) or off-axis (toward the end of the process cable at an angle greater than the threshold, resulting in equal or greater than threshold reflections within the process cable). In the former case, the beam may have a spot profile at the input to the process cable and a spot profile at the output from the process cable, which is desirable when cutting relatively thin metals. In the latter case, the beam may have a spot profile at the input side of the process cable and a ring profile at the output side of the process cable, which is desirable when cutting relatively thick metals.

[0012] Pedestal optics can be introduced into an optical coupler (e.g., between an optical emitter and a lens of the optical coupler) to change the beam profile. The pedestal optic can receive a portion of the beam output from the optical emitter and direct a portion of the beam off-axis (e.g., while the remaining beam remains on-axis). Thus, the process cable receives both the on-axis and off-axis portions of the beam, and as a result, the process cable outputs both a spot profile portion of the beam and a ring profile portion of the beam. By controlling the amount of beam splitting with the pedestal optic, the spot profile portion of the beam can be made larger than the ring profile portion, resulting in a pedestal profile (e.g., a profile that includes a ring portion with a spot in the center of the ring portion, rather than a cavity in the center of the ring portion as in a pure ring profile). That is, by adjusting the pedestal optic, the pedestal shape can be adjusted (e.g., the relative amounts of optical energy in the ring portion and the spot portion of the beam can be changed), which is desirable in some use cases. However, in other use cases, a vortex beam profile is desirable, as it has an annular beam shape along the entire beam profile and produces very sharp beam edges, allowing for precise control of the beam.

[0013] 1A-1B are diagrams of an embodiment 100 relating to beam control of a light beam. As shown in FIG. 1A-1B, the embodiment 100 includes a light emitter 110, a collimating lens 120, a light shaper 130, a focusing lens 140, and a process cable 150.

[0014] The light emitter 110 may include a vertical cavity surface emitting laser (VCSEL). For example, the light emitter 110 may be configured to output a beam having a particular beam profile toward the collimating lens 120. In some embodiments, the light emitter 110 may be configured for a beam having a power greater than a threshold. For example, the light emitter 110 may have an optical power of greater than 1 kilowatt (kW), greater than 3 kW, greater than 5 kW, greater than 10 kW, or more. The collimating lens 120 may collimate the beam and direct the beam to the light shaper 130. The light shaper 130 may shape the beam and direct it to the collection lens 140, which may direct the beam to the process cable 150. In other embodiments, other combinations of optical components may be disposed in the light shaper. For example, the light shaper 130 may be disposed directly on the light emitter 110 (e.g., without the collimating lens 120) and / or directly on the process cable 150 (e.g., without the collecting lens 140). Additionally or alternatively, additional optical components may be included in the beam path, such as an optical filter disposed between the light emitter 110 and the collimating lens 120. Additionally or alternatively, the light shaper 130 may be disposed on a combination of different components. For example, rather than coupling the light emitter 110 to the process cable 150, the light shaper 130 may couple a first process cable to a second process cable. In some implementations, the light shaper 130 and one or more other optical components (e.g., the collimating lens 120 or the collecting lens 140, among other examples) may be packaged together as an optical coupler. In other words, some optical systems can include, among other optical components, an optical emitter 110, an optical coupler, and a process cable 150, and the optical coupler can include a set of optical components such as a collimating lens 120, an optical shaper 130, or a focusing lens 140, among other examples.

[0015] In some embodiments, the light shaper 130 may include a set of optical elements. For example, the light shaper may include a first optical element 132 and a second optical element 134. In this case, at least one of the first optical element 132 or the second optical element 134 may be movable relative to the other to enable beam shaping. For example, in FIG. 1A, a first beam shape 170a is achieved in the near field before rotation of the optical element 134. In contrast, in FIG. 1B, a second beam shape 170b is achieved in the near field after rotation of the optical element 134. As described in more detail herein, moving the optical element 132 or 134 may change the beam shape in the far field.

[0016] In some embodiments, the optical element 132 / 134 can be a particular type of optical element. For example, the optical element 132 / 134 can be a set of prisms. In some embodiments, the optical element 132 / 134 can be made of a particular type of material. For example, the optical element 132 / 134 can include a glass material, a fused silica material (e.g., infrared grade fused silica), a sulfide material, a crystalline material (e.g., an yttrium aluminum garnet (YAG) material, such as undoped YAG), or a sapphire material, among other examples. In some embodiments, the optical element 132 / 134 (or another optical component described herein) can have one or more functional layers deposited on one or more surfaces. For example, the surface of the optical element 132 / 134 can include an anti-reflection (AR) coating, a dichroic coating, which can reduce or eliminate stimulated Raman scattering (SRS).

[0017] In some embodiments, the optical elements 132 / 134 may have a particular shape. For example, the optical elements 132 / 134 may be pyramidal prisms (e.g., 4-sided pyramids) with three sides and a base, as shown. By using a three-sided pyramidal prism, the light shaper 130 can maintain the shape of the field of the beams when they are recombined (e.g., as a hexagonal close-packed shape), as described in more detail herein. Other numbers of optical elements, types of optical elements, or shapes of optical elements are also contemplated. For example, a set of two-sided optical elements can steer the beams and change the shape of the field of the beams when they are recombined (e.g., as two back-to-back semicircles).

[0018] In some embodiments, the optical elements 132 / 134 can shape the beam traveling straight through the light shaper 130. For example, the three sides of the first optical element 132 can split the beam into three parts with three different directions. The three parts of the beam can propagate in three different directions from the bottom surface of the optical element 132 to the bottom surface of the optical element 134. The three parts of the beam can propagate through the optical element 134 to the three sides of the optical element 134. The three sides of the optical element 134 can redirect the three parts of the beam in a single direction as a single beam toward the focusing lens 140. In other words, the beam enters the optical element 132 as a parallel beam (e.g., with a hexagonal close-packed field shape), propagates from the optical element 132 to the optical element 134 as a non-parallel beam, and exits the optical element 134 as a parallel beam (e.g., with the hexagonal close-packed field shape maintained).

[0019] In some embodiments, the separation between the optical elements 132 / 134 may be related to the geometry of the optical elements 132 / 134. For example, an optical element 132 / 134 having a flattened pyramid shape may have a larger separation than an optical element 132 / 134 having an angular (e.g., less flattened or steeper) pyramid shape. In some implementations, the rotational difference between the optical elements 132 / 134 is related to the optical properties of the output beam (e.g., from the light shaper 130 and / or the process cable 150). For example, the optical elements 132 / 134 may be rotated 180 degrees from each other as shown to maintain a hexagonal close-packed arrangement of the beam field and maintain the brightness of the beam.

[0020] In some embodiments, the relative positions of the optical elements 132 / 134 can be changed to change the characteristics of the beam (e.g., in the far field, while maintaining the near field beam). For example, the optical element 134 can be translated or rotated relative to the optical element 132 (or vice versa) to change the characteristics of the beam. In some embodiments, the optical element 134 can be mounted on a moving member, such as a rotational or translational motor, so that it can be moved relative to the optical element 132 (or vice versa). Additionally or alternatively, the optical elements 132 / 134 can be mounted on a platform or housing that allows for manual adjustment. Relative translation of the optical element 134 with respect to the optical element 132 can cause a change in the near field (e.g., by widening or shrinking the near field of each portion of the beam).

[0021] Similarly, rotation of optical element 134 relative to optical element 132 can cause a change in the near field (e.g., by causing portions of the beam to converge or diverge). For example, as shown in FIG. 1A, in a first relative position of optical elements 132 / 134, the beam shape at the input to process cable 150 has the three portions of the beam nearly overlapping. In contrast, as shown in FIG. 1B, in a second relative position of optical elements 132 / 134 (e.g., rotation of optical element 134 relative to the optical axis of the beam), the three portions of the beam diverge toward the edges of the beam's field.

[0022] As noted above, FIGS. 1A-1B are presented as an example. Other implementations may differ from those described with respect to FIGS. 1A-1B. The number and arrangement of devices shown in FIGS. 1A-1B are presented as an example. In practice, there may be additional devices, fewer devices, different devices, or different arrangements of devices than those shown in FIGS. 1A-1B. Furthermore, two or more devices shown in FIGS. 1A-1B may be implemented within a single device, or a single device shown in FIGS. 1A-1B may be implemented as multiple distributed devices. Additionally or alternatively, a set of devices (e.g., one or more devices) shown in FIGS. 1A-1B may perform one or more functions described as being performed by another set of devices shown in FIGS. 1A-1B.

[0023] 2A-2B are diagrams of an embodiment 200 relating to beam control of an optical beam. As shown in FIGS. 2A-2B, a beam directed through an optical coupler, such as optical shaper 130, may have a first beam profile in a near field and a second beam profile in a far field, which may be a point outside (or at the end) of the process cable through which the beam propagates. As shown in FIG. 2A, at a first relative position of the pyramidal prism in the optical coupler, the beam may have a point profile in the near field and a first shape in the far field. For example, the beam profile of the first shape may have a beam parameter product (BPP) of about 1.4 millimeters by milliradians (mm-mrad). In some embodiments, the first beam shape may be a point beam shape or a split beam shape, relative to the relative positions of the optical elements of the optical coupler.

[0024] As shown in FIG. 2B, when at least one of the pyramidal prisms moves relative to another one of the pyramidal prisms in the optical coupler, the beam profile changes to a number of points with angular momentum in the near field and to a second shape (e.g., a vortex profile or annular beam) in the far field. For example, the second shape beam profile may have a maximum BPP of about 12 mm-mrad. In some embodiments, the second shape may have a helical structure. For example, the second shape may be an annular beam shape (e.g., extending along the entire output beam profile) or a vortex mode beam shape. Additionally or alternatively, the second shape may have reduced optical power at a center point (e.g., the axis of movement of the beam) compared to the first shape. Additionally or alternatively, the second shape may have a steeper slope than the first shape. In other words, the transition between the first optical power level (e.g., a local minimum) and the second optical power level (e.g., a local maximum) may occur over a shorter physical distance across the beam profile in the second shape compared to the first shape.

[0025] In this way, the pair of pyramid prisms can be used to improve the edge sharpness of the annular beam. For example, the pair of pyramid prisms can achieve a threshold level of edge sharpness. Additionally or alternatively, the pair of pyramid prisms can provide an annular beam (e.g., a vortex beam) in both the near and far fields. Additionally or alternatively, the pair of pyramid prisms can improve the dynamic range of the beam parameter products and provide rotation-based decoupling of the beam adjustment (e.g., decoupling of the rotation-based beam adjustment from vibrations along the translation axis).

[0026] As noted above, Figures 2A-2B are provided as an example, and other implementations may differ from those described with respect to Figures 2A-2B.

[0027] Figure 3 is a flow chart of an example process 300 associated with beam control of a light beam. In some implementations, one or more of the process blocks in Figure 3 are performed by a controller. For example, one or more of the process blocks in Figure 3 may be performed by a linear motor (or an electronic controller thereof), a rotary motor (or an electronic controller thereof), an actuation component (e.g., for linear or rotational actuation), or another type of control device. In some implementations, one or more of the process blocks in Figure 3 are performed by a device or devices that include a device separate from the controller.

[0028] 3, process 300 may include placing a pair of optical elements of an optical device in a first position (block 310). For example, the controller may set the relative positions of a first optical element and a second optical element in the optical device in the optical system to a first relative position, as described above. In some implementations, the first optical element and the second optical element are a pair of pyramidal prisms. In some implementations, the optical system outputs a beam having a first beam shape with the relative position set to the first relative position, as described above.

[0029] 3, in some embodiments, the process 300 may include determining an output of a set of optical elements of the optical device at a first position (block 320). For example, as described above, the controller may receive feedback indicating a beam shape of a beam being output from the optical device. In this case, the controller may determine to change the beam shape. Additionally or alternatively, the controller may be triggered to change the beam shape without receiving a feedback signal.

[0030] 3, the process 300 may include adjusting an orientation of a set of optical elements of the optical device to a second position to change the output (Block 330). For example, as described above, the controller may adjust the relative position of a first optical element and a second optical element in the optical device to a second relative position within the optical system. In some implementations, the optical system outputs a beam having a second beam shape with the relative position set to the second relative position.

[0031] Process 300 may include additional implementations, such as any single implementation or any combination of the implementations described below and / or in conjunction with one or more other processes described elsewhere herein.

[0032] In a first embodiment, the process 300 includes receiving feedback identifying a first beam shape, and adjusting the relative position to a second relative position includes adjusting the relative position to the second relative position in association with a control signal related to the feedback.

[0033] In a second embodiment, alone or in combination with the first embodiment, the step of adjusting the relative position to the second relative position comprises translating or rotating at least one of the first optical element or the second optical element.

[0034] In a third embodiment, alone or in combination with one or more of the first and second embodiments, the process 300 includes coupling an optical device to an optical fiber in an optical system.

[0035] Although Figure 3 illustrates example blocks of process 300, in some implementations, process 300 includes additional, fewer, different, or differently arranged blocks than those illustrated in Figure 3. Additionally, or alternatively, two or more of the blocks of process 300 may be performed in parallel.

[0036] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the embodiments. Further, the embodiments described herein may be combined unless the foregoing disclosure explicitly provides a reason why one or more embodiments cannot be combined.

[0037] As used herein, satisfying a threshold can mean, depending on the context, that a value is greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc.

[0038] Even if certain combinations of features are disclosed in the claims and / or specification, these combinations are not intended to limit the disclosure of the various embodiments. Indeed, many of these features can be combined in ways not specifically described in the claims and / or specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of the various embodiments includes each dependent claim in combination with all other claims in the claim set. As used herein, language regarding "at least one" of a list of items refers to any combination of those items, including single elements. As an example, "at least one of a, b, or c" is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination with multiples of the same items.

[0039] When an element or more than one element (e.g., a laser emitter or one or more laser emitters) is described or claimed (in a single claim or across multiple claims) as performing or configured to perform multiple operations, this language is intended to broadly cover a variety of configurations and environments. For example, unless expressly asserted otherwise (e.g., by using in the claim "first component" and "second component" or other language that distinguishes the components), this language is intended to cover a single component that performs or is configured to perform all of the operations, a collection of components that perform or are configured to perform all of the operations, a first component that performs or is configured to perform a first operation and a second component that performs or is configured to perform a second operation, or any combination of components that perform or are configured to perform operations. For example, if a claim has the format "one or more components configured to perform X, perform Y, and perform Z," the claim should be interpreted to mean "one or more components configured to perform X, one or more (possibly different) components configured to perform Y, and one or more (also possibly different) components configured to perform Z."

[0040] No element, act, or instruction used herein should be construed as critical or essential unless expressly described as such. Also, as used herein, the articles "a" and "an" are intended to include one or more items and may be used interchangeably with "one or more." Additionally, as used herein, the article "the" is intended to include one or more items referenced in connection with the article "the" and may be used interchangeably with "the one or more." Additionally, as used herein, the term "set" is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items) and may be used interchangeably with "one or more." When only one item is intended, "only one" or similar language is used. Also, as used herein, terms such as "has," "have," "having," and the like are intended to be open-ended terms. Additionally, the phrase "based on" is intended to mean "based, at least in part, on," unless expressly stated otherwise. Also, as used herein, the term "or" when used in a series is intended to be inclusive and may be used interchangeably with "and / or" unless expressly stated otherwise (e.g., when used in combination with "either" or "only one of"). Additionally, spatially relative terms such as "below," "lower," "above," "upper," and the like may be used herein to describe the relationship of one element or feature to another element(s) or feature(s) as shown in the figures for ease of description.Spatially relative terms are intended to encompass different orientations of the apparatus, device, and / or element during use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may be interpreted accordingly.

Claims

1. 1. An optical device comprising: a first optical element that is a first prism; and a second optical element, which is a second prism; and Equipped with The optical device is configured to receive a beam and output the beam, and the first optical element and the second optical element are configured to modify a beam shape of the beam such that the beam has a first shape at a first position and a second shape at a second position.

2. 2. The optical device according to claim 1, wherein the first prism and the second prism are pyramidal prisms.

3. 10. The optical device of claim 1, wherein the second shape is an annular beam shape having a threshold level of edge sharpness.

4. The optical device of claim 1 , wherein at least one of the first optical element or the second optical element is movable to adjust the second shape.

5. 2. The optical device of claim 1, wherein at least one of the first optical element or the second optical element is rotatable about an axis of a beam path formed by the beam between the first optical element and the second optical element.

6. The optical device of claim 1 , wherein the optical device is configured to split the beam into a plurality of components at the first location.

7. 1. An optical system comprising: a collimating lens for collimating the beam; a focusing lens for focusing the beam; and an optical device for shaping the beam, the optical device being disposed between the collimating lens and the condenser lens, the optical device comprising: A first pyramidal prism, and A second pyramidal prism; Including, the first pyramidal prism and the second pyramidal prism are positioned such that the beam has a first beam shape in a near field and a second beam shape in a far field; An optical system comprising:

8. 8. The optical system of claim 7, further comprising an optical emitter that emits a beam toward the collimating lens.

9. 8. The optical system of claim 7, further comprising a process cable receiving the beam from the collection lens and directing the beam to a target.

10. 10. The optical system of claim 9, wherein the near field is at an input of the process cable and the far field is at an output of the process cable.

11. 10. The optical system of claim 9, wherein the near field is at an input of the process cable and the far field is at a target outside of the process cable and located at an output of the process cable.

12. 10. The optical system of claim 9, wherein at a first relative position of the first pyramid prism and the second pyramid prism, the first beam shape is a point beam shape and the second beam shape is an annular beam shape, and at a second relative position of the first pyramid prism and the second pyramid prism, the first beam shape is a split beam shape and the second beam shape is a vortex mode beam shape.

13. 10. The optical system of claim 9, wherein the optical system is configured to output an annular beam shape that extends along an entire output beam profile.

14. 10. The optical system of claim 9, wherein the optical system is configured to output the beam having an annular beam shape and an edge steepness of the annular beam shape that exceeds a threshold edge steepness.

15. 10. The optical system of claim 9, further comprising an actuating component configured to linearly move at least one of the first pyramidal prism or the second pyramidal prism relative to a beam path formed by the beam.

16. 10. The optical system of claim 9, further comprising an actuating component configured to rotationally move at least one of the first pyramidal prism or the second pyramidal prism about an axis of a beam path formed by the beam.

17. 1. A method comprising: setting, by a controller, a relative position of a first optical element and a second optical element in an optical device in the optical system to a first relative position; the first optical element and the second optical element are a pair of pyramidal prisms; a step of setting the optical system to output a beam having a first beam shape with the relative position set to the first relative position; and adjusting, by the controller, the relative position of the first optical element and the second optical element in the optical device in the optical system to a second relative position; the optical system outputs a beam having a second beam shape with the relative position set to the second relative position; A method comprising:

18. 20. The method of claim 17, further comprising the step of receiving feedback identifying the first beam shape, The method of claim 1, wherein adjusting the relative position to the second relative position includes adjusting the relative position to the second relative position in relation to a control signal related to feedback.

19. 20. The method of claim 17, wherein adjusting the relative position to the second relative position comprises translating or rotating at least one of the first optical element or the second optical element.

20. 20. The method of claim 17, further comprising coupling the optical device to an optical fiber in the optical system.

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