Beam shaping module for multidimensional beam shaping, lidar system, method for multidimensional beam shaping, method and device for controlling a beam shaping module and method for manufacturing a beam shaping module

Abstract

Beam shaping module (100) for multidimensional beam shaping, wherein the beam shaping module (100) has the following features: at least a phase-controlled array (102) with a plurality of emitter elements (104) for generating electromagnetic radiation and at least one phase-shifting element (106) for imprinting a defined phase profile onto the radiation; and at least one deflection element (108) downstream of the array (102) for deflecting emission radiation emitted by the array (102) and having the phase profile in a deflection direction that differs from an emission direction of the emission radiation.

Description

State of the art

[0001] The invention relates to a device or a method according to the preamble of the independent claims. The present invention also relates to a computer program.

[0002] The publication "Integrated phased array for wide-angle beam steering" (Yaacobi et al., Optics Letters, Vol. 39, No. 15, 2014) describes how a one-dimensional optical phased array, also called an optical phased array or OPA (or 1D-OPA), is suitable for beam deflection in lidar applications. By arranging several such 1D-OPAs on a single chip with different grating periods, multiple scan planes can be realized, thus enabling two-dimensional scanning.

[0003] Prior art describes arrangements of light sources, such as surface emitters (VCSELs), on a rectangular grid or matrix arrangement. Positioning these arrangements within the focal plane of a lens allows for controlled beam deflection, for example, in lidar systems (Lidar = light detection and ranging). Geometrically and optically, beam shaping can be explained by the effect of a focusing lens on collimated beams and point sources within a focal plane. Parallel incident rays are focused within the focal plane. The position within the focal plane depends on the angle of incidence of the beam. Conversely, a point source within the focal plane produces a collimated beam. The exit angle depends on the lateral displacement of the (point) source from the optical axis.

[0004] Furthermore, (optical) phase-controlled arrays are known that allow beam shaping, or preferably beam deflection in lidar systems, not by means of reflective optical elements such as mirrors or refractive optical elements such as lenses, but rather based on diffraction at diffractive optical elements. By using phase shifters, it is possible to impose a phase profile on the emitted light, producing a desired intensity profile in the far field.

[0005] The operating principle of a phased array is comparable to that of a diffractive optical element. In the case of a phased array, beam shaping in the far field is made possible by different phase levels in the individual emitters. With constant phase, a central intensity maximum is obtained in the far field in the zeroth diffraction order, depending on the spacing and periodicity of the arrangement of the phase shifters with additional grating lobes in the positive or negative first diffraction order and further side lobes.

[0006] Simple beam deflection is possible, for example, by applying a linear phase profile. By appropriately designing the phase distribution, for example using the Gerchberg-Saxton algorithm, also known as the iterative Fourier transform algorithm or IFTA in conjunction with diffractive optical elements, virtually any far-field intensity distribution can be realized.

[0007] Another method of beam deflection involves the use of prisms or diffractive structures such as blaze gratings. The advantage of diffractive structures is that they can also be implemented on programmable optical elements such as spatial light modulators (SLMs).

[0008] From US 2017 / 0131615A1, a device is known that forms a photonic phased-array antenna, wherein the device comprises at least one light source, an optical power distributor, a phase controller, and a light wave emitter.

[0009] From US 2018 / 0039154A1, an optical device is known which comprises a series of optical units, each of which includes an antenna element and an associated phase-shifting element, a first optical power divider, and a first plurality of boundary-matching elements.

[0010] The document "Rabinovich et al.: Two-dimensional beam steering using a thermooptic silicon photonic optical phased array" discloses a silicon photonic phased array (OPA) that enables two-dimensional beam deflection via the thermo-optic effect. Deflection in one dimension is achieved by heating waveguides, and in the orthogonal dimension by heating an output coupling grating, without requiring wavelength tuning of the laser.

[0011] The document "Heck, Martijn: Highly integrated optical phased arrays: Photonic integrated circuits for optical beam shaping and beam steering" provides an overview of optical phased arrays (OPAs) as photonic integrated circuits (PICs), particularly those based on silicon photonics. It describes how two-dimensional beam deflection is achieved through a combination of phase control in one dimension and wavelength tuning of the laser for the second dimension.

[0012] Document US 5,093,563 A discloses an optical imaging system with an array of sub-telescopes, each equipped with heterodyne detectors to capture the amplitude and phase of the incident light. Image combination and phase error correction are performed electronically after detection, thereby achieving a synthetic large aperture without optical phase compensation elements.

[0013] Document US 2010 / 0187442 A1 discloses an integrated photonic beam steering device on a planar photonic substrate that utilizes a phased array. The device includes input waveguides, splitters, phase modulators, and outcouplers to emit a controlled photonic beam. Disclosure of the invention

[0014] Against this background, the approach presented here introduces a beam shaping module for multidimensional beam shaping, a lidar system, a method for multidimensional beam shaping, a method and a device for controlling a beam shaping module, a corresponding computer program, and a method for manufacturing a beam shaping module according to the main claims. Advantageous further developments and improvements of the device specified in the independent claim are possible through the measures listed in the dependent claims.

[0015] The approach presented here is based on the understanding that multidimensional beam shaping can be achieved by combining an optical phased array, for example a one-dimensional array, with a deflection structure, which may include prisms or diffraction gratings. Corresponding optical setups and beam shaping methods for arrangements of such optical phase arrays can advantageously be used for multidimensional beam shaping and deflection in lidar systems, for example by orthogonal beam deflection of the radiation emitted by the phase array.

[0016] The angular resolution in conventional arrangements of light sources with a downstream lens is generally limited by the number and packing density of the light sources in the matrix arrangement. Furthermore, the numerical aperture of the light sources and the focal length of the lens limit the minimum beam diameter of the emitted beams. The matrix arrangement also dictates a mandatory discretization of the angular space in which light can be emitted.

[0017] By using lithographic manufacturing processes for integrated optical components such as waveguides, very small emitter spacings can be achieved in optical phased arrays. In this case, the minimum emitter spacing can be a limiting factor for the maximum possible diffraction angle and thus for the maximum possible beam deflection. Optical phased arrays offer, in principle, the possibility of almost arbitrary beam shaping, similar to so-called spatial light modulators (SLM). However, the fabrication of integrated two-dimensional optical phased arrays can lead to significant complexity in system design and high costs and failure risks during manufacturing.

[0018] In contrast, the approach presented here offers a means of two-dimensional beam deflection using an arrangement of one-dimensional phase arrays. This is particularly advantageous because one-dimensional arrays are relatively simple and inexpensive to manufacture. Further benefits arise when, for example, the beam deflection in the two transverse dimensions needs to meet different requirements, as is the case in lidar systems for automotive applications, where the requirements for field of view and resolution can differ significantly in the horizontal and vertical directions. OPA arrangements offer considerably more possibilities for adaptive beam shaping than simple matrix arrays of light sources.

[0019] Depending on the embodiment, it is also possible to control the intensity relative to the maximum intensity of a single optical phased array, with which the overall system illuminates a predetermined angular range, via the number of active optical phased arrays, and thus, for example, to achieve higher intensities in large deflection angles.

[0020] Furthermore, according to one embodiment, it is possible to monitor the entire field of view in several directions simultaneously by appropriately controlling the individual optical phase-controlled arrays, if a suitable receiver is used.

[0021] According to another embodiment, it is also possible to superimpose beam lobes of several optical phased arrays, which leads to a higher far-field intensity and thus to a greater range in the corresponding spatial direction.

[0022] Furthermore, the approach presented here includes methods for a particularly cost-effective and easy-to-implement deflection orthogonal to the deflection of the optical phase-controlled array using switchable components such as area light modulators or switchable holograms with adapted resolution and angular range.

[0023] Another embodiment enables flexible deflection with fine resolution, limited, for example, only by beam divergence, using optical phased arrays. The generation of two-dimensional far-field distributions can be achieved, for example, by combining several optical phased arrays, particularly with non-parallel deflection axes, in the simplest case perpendicular to each other.

[0024] Furthermore, it is also possible, for example, to superimpose different interference patterns with overlapping intensity ranges to generate different intensity levels. This can be helpful, for instance, to increase the diffraction efficiency in the deflected beam within certain angular ranges, since this efficiency typically decreases for larger deflection angles, for example due to sinc modulation in the far field or, more generally, due to the element factor of the individual emitters.

[0025] A beam shaping module for multidimensional beam shaping is presented, wherein the beam shaping module has the following features: at least a phased array with a plurality of emitter elements for generating electromagnetic radiation and at least one phase-shifting element for imprinting a defined phase profile onto the radiation; and at least one deflection element downstream of the array for deflecting emission radiation emitted by the array and exhibiting the phase profile into a deflection direction that differs from an emission direction of the emission radiation.

[0026] Multidimensional beam shaping can be understood as beam shaping and / or deflection in at least two dimensions, for example, in two transverse dimensions. A phased array can be understood as an optoelectronic device, also called an optical phased array or OPA for short, for beam shaping using variable surface elements without moving parts such as lenses or mirrors. For example, the array can be implemented as a one-dimensional array. Electromagnetic radiation can be understood as, for example, laser radiation. The term radiation can be understood as at least one (idealized linear) beam or at least a beam of radiation. An output beam emitted by a LiDAR system has a finite diameter.In geometric-optical terms, this refers, for example, to a beam of rays, just as a laser beam is geometrically modeled as a bundle of parallel rays. An emitter element can be, for example, a laser source. An optical phase array, for instance, uses coherent light emitted by multiple emitters as its emitter element, with interference occurring in the far field. The interference pattern then depends, for example, on the phase shift between the individual emitters. To achieve favorable coherence, individual laser elements are not used directly as emitters. Instead, a laser element is integrated into or coupled into a photonic chip to split the coherent light via waveguide structures and feed it to the individual phase shifters and subsequent emitters (e.g., grating structures for outfeed or simple edge emitters).At the emitters, the light is then coupled out of the phase array chip and interferes during subsequent free-space propagation, leading, for example, to a corresponding interference pattern in the far field. The phase-shifting element can be a diffractive optical element for phase shifting via diffraction. Phase shifting in optical phase arrays is achieved, for example, through thermo-optical or electro-optical effects. In liquid crystal-based SLMs, the refractive index is controlled by the orientation of the crystals. Most diffractive optical elements rely on locally changing the refractive index through a surface profile, index modulation, thermal effects, or applied voltages, resulting in a change in the interference pattern in the far field compared to a constant refractive index.It is therefore generally advantageous to generate a phase shift that produces a desired diffraction pattern. The phase shifter element can, for example, be designed to imprint the phase profile in such a way that a specific intensity distribution is generated in the far field of the beam shaping module. Integrated optical phase arrays should generally contain several phase shifters, e.g., at least one for each emitter channel.

[0027] On the other hand, a liquid crystal-based SLM can of course be considered a single phase-shifting element. A deflection element can be, for example, a refractive, reflective, or diffractive surface, a diffractive optical element, a holographic optical element, a surface light modulator, a prism, a diffraction grating, or a combination of at least two of the aforementioned optical elements, for example, in the form of a deflection structure or a deflection array.

[0028] According to one embodiment, the array can have a plurality of emission surfaces, each assigned to an emitter element, for emitting the emission radiation. The emission surfaces can be arranged at a defined distance from one another to form a one-dimensional array. By using, for example, lithographic processes for the fabrication of integrated optical components, the beam shaping module can be manufactured particularly cost-effectively.

[0029] According to another embodiment, the deflection element can be designed to deflect the emission radiation in a deflection direction orthogonal to the emission direction or, additionally or alternatively, in different deflection directions. This allows the beam shaping module to be used for beam shaping in lidar systems.

[0030] Depending on the embodiment, the deflection element can comprise a refractive, reflective, or diffractive surface, a diffractive optical element (DOE), a holographic optical element (HOE), a surface light modulator (SLM), a prism, a diffraction grating (e.g., in the form of a blaze grating), or a combination of at least two of the aforementioned optical elements. This allows the deflection element to be provided relatively inexpensively.

[0031] The beam shaping module can also include a collimation element positioned between the array and the deflection element to collimate the emission radiation. The deflection element can be designed to deflect emission radiation collimated by the collimation element. A collimation element can be understood as an optical element for rectifying multiple light beams. For example, the collimation element can be implemented as a lens or lens array. This allows the far-field divergence of individual emitter elements to be controlled.

[0032] According to a further embodiment, the beam shaping module can be realized with at least one further phased array with a plurality of further emitter elements for generating further electromagnetic radiation and at least one further phase shifter element for imprinting a further defined phase profile onto the further radiation, and at least one further deflection element downstream of the further array for deflecting further emission radiation emitted by the further array and exhibiting the further phase profile into a further deflection direction that differs from a further emission direction of the further emission radiation. This allows the beam shaping module to be manufactured simply and cost-effectively with a two-dimensional optical phased array composed of two one-dimensional optical phased arrays.Furthermore, the beam shaping module can be implemented with a plurality of OPA channels, which, for example, enables simultaneous illumination of different angular ranges or the superposition of different interference patterns.

[0033] According to one embodiment, the array and the further array can be oriented perpendicular to each other and / or stacked on top of each other and / or connected to form an array assembly. This allows the beam shaping module to be designed to be particularly compact, among other things.

[0034] The approach described here also creates a lidar system with at least one beam shaping module according to one of the above embodiments.

[0035] Furthermore, the approach described here provides a method for multidimensional beam shaping using a beam shaping module according to one of the preceding embodiments, wherein the method comprises the following steps: Emitting the emission radiation in the direction of emission; and

[0036] Deflecting the emission radiation in the direction of deflection to achieve multidimensional beam shaping.

[0037] Furthermore, the approach described here provides a method for controlling a beam shaping module according to one of the preceding embodiments, wherein the method comprises the following step: Output of a first control signal to control the array and / or the deflection element and a second control signal to control the further array and / or the further deflection element in order to simultaneously illuminate different angular ranges of a space surrounding the steel forming module.

[0038] According to one embodiment, the first and second control signals can be output simultaneously in the output step to illuminate at least partially overlapping angular ranges and / or to superimpose different interference patterns. This can significantly increase the diffraction efficiency of the combined arrays in certain angular ranges.

[0039] Finally, the approach presented here provides a method for manufacturing a beam shaping module according to one of the preceding embodiments, wherein the method comprises the following step: Combining the array with the deflection element so that the deflection element is downstream of the array to create the beam shaping module.

[0040] These methods can be implemented, for example, in software or hardware, or in a hybrid form of software and hardware, such as in a control unit.

[0041] The approach presented here further creates a device designed to perform, control, and implement the steps of a variant of the method presented here in appropriate facilities. This embodiment of the invention in the form of a device also allows the problem underlying the invention to be solved quickly and efficiently.

[0042] For this purpose, the device may include at least one processing unit for processing signals or data, at least one storage unit for storing signals or data, at least one interface to a sensor or actuator for reading sensor signals from the sensor or for outputting data or control signals to the actuator, and / or at least one communication interface for reading or outputting data embedded in a communication protocol. The processing unit may, for example, be a signal processor, a microcontroller, or the like, and the storage unit may be flash memory, an EPROM, or a magnetic storage device.The communication interface can be configured to read or output data wirelessly and / or via wired connections, whereby a communication interface that can read or output wired data can, for example, read this data electrically or optically from or output it into a corresponding data transmission line.

[0043] In this context, a device can be understood as an electrical device that processes sensor signals and outputs control and / or data signals accordingly. The device may have an interface, which can be implemented in hardware and / or software. In the case of a hardware-based interface, the interfaces can, for example, be part of a so-called system ASIC, which incorporates various functions of the device. However, it is also possible that the interfaces are separate integrated circuits or consist at least partially of discrete components. In the case of a software-based interface, the interfaces can be software modules, which, for example, are located on a microcontroller alongside other software modules.

[0044] Also advantageous is a computer program product or computer program with program code that can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and is used to carry out, implement and / or control the steps of the method according to one of the embodiments described above, in particular if the program product or program is executed on a computer or device.

[0045] Exemplary embodiments of the invention are shown in the drawings and explained in more detail in the following description. It shows: Fig. 1 a schematic representation of a beam shaping module according to an exemplary embodiment; Fig. 2 a schematic representation of a beam shaping module according to an exemplary embodiment; Fig. 3 a schematic representation of a beam shaping module according to an exemplary embodiment; Fig. 4 a schematic representation of a phased array from the Fig. 1 to 3 in the top view; Fig. 5 a schematic representation of a phased array from the Fig. 1 to 4 with idealized representation of the emitter elements as spherical wave emitters; Fig. 6 diagrams illustrating a phase profile, emitter apertures in the amplitude profile, and a far-field intensity of a phased array from the Fig. 1 to 5; Fig. 7 diagrams for representing a phase profile, emitter apertures in the amplitude profile and a far-field intensity of a phased array from the Fig. 1 to 5; Fig. 8 diagrams for representing a phase profile, emitter apertures in the amplitude profile and a far-field intensity of a phased array from the Fig. 1 to 5; Fig. 9 diagrams illustrating the amplitude and far-field intensity of a phased array from the Fig. 1 to 5; Fig. 10 diagrams for representing the amplitude and far-field intensity of a phased array from the Fig. 1 to 5; Fig. 11 diagrams for representing the amplitude, phase, and far-field intensity of a phased array from the Fig. 1 to 5; Fig. 12 diagrams for representing the amplitude, phase, and far-field intensity of a phased array from the Fig. 1 to 5; Fig. 13 a diagram for representing a far field of a horizontal phased array according to an embodiment; Fig. 14 a diagram illustrating a far field of a vertical phased array according to an embodiment; Fig. 15 a flowchart of a method for multidimensional beam shaping according to an exemplary embodiment; Fig. 16 a flowchart of a method for controlling a beam shaping module according to an embodiment; Fig. 17 a flowchart of a method for manufacturing a beam shaping module according to an exemplary embodiment; Fig. 18 a schematic representation of a device according to an exemplary embodiment; and Fig. 19 A schematic representation of a lidar system according to an exemplary embodiment.

[0046] In the following description of favorable embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and acting similarly, without repeating these elements.

[0047] Fig. Figure 1 shows a schematic representation of a beam shaping module 100 according to an exemplary embodiment. The beam shaping module 100 comprises an optical phase-controlled array 102 with a plurality of emitter elements 104 for generating electromagnetic radiation, such as laser radiation. Each of the emitter elements 104 includes, by way of example, a phase shifter element 106 for imprinting a defined phase profile onto the radiation generated by the emitter elements 104 by shifting a respective phase φ. A deflection element 108 is connected downstream of the array 102, which is configured to deflect the radiation emitted by the array 102 with the defined phase profile in a defined deflection direction. In this way, it is possible to shape or deflect the radiation multidimensionally, here two-dimensionally.

[0048] According to this embodiment, the array 102 is realized as a one-dimensional array with emitter elements 104 arranged in a plane, as also shown in Fig. 4 is visible.

[0049] According to the in Fig. In the embodiment shown in Figure 1, the beam shaping module 100, in addition to the array 102, has a plurality of further arrays 110, which, analogous to the array 102, are each realized as a one-dimensional array with a plurality of further emitter elements 112 for generating further electromagnetic radiation and a plurality of further phase-shifting elements 114 for imprinting a further phase profile onto the further radiation. Each of the further arrays 110 is followed by a further deflection element 116, which is designed analogously to the deflection element 108, in order to deflect the radiation emitted by the further arrays 110 with the respective further phase profile in a defined further deflection direction. By way of example, the deflection element 108 and the further deflection elements 116 are realized as partial surfaces of a planar deflection structure.

[0050] Depending on the embodiment, the arrays 102, 110 are realized as a stacked arrangement with deflection structures such as prisms, gratings, diffractive optical elements, or DOE for short, or area light modulators, or SLM for short, for beam deflection in a complementary direction.

[0051] The beam shaping module 100, for example, is a component of a lidar system, as schematically shown in Fig. 19 is shown.

[0052] Fig. Figure 2 shows a schematic representation of a beam shaping module 100 according to an exemplary embodiment. The stacked arrangement is shown. Fig. 1, here with optional collimation optics 200 for controlling the far-field divergence of the individual emitter elements 104, 112.

[0053] Fig. Figure 3 shows a schematic representation of a beam shaping module 100 according to an exemplary embodiment. The stacked arrangement of the components is shown. Fig. 1 or Fig. 2, here with an additional phase-controlled array 300 and an additional deflection element 302 for deflection in an orthogonal plane. The additional array 300 is implemented as a one-dimensional array, analogous to arrays 102 and 110. The additional array 300 with the associated deflection element 302 is, for example, arranged on opposite sides of the stacked arrangement. Arrays 102, 110, and 300 are, for example, implemented as a composite array.

[0054] Fig. Figure 4 shows a schematic representation of a phased array 102 from the Fig. 1 to 3 in the top view.

[0055] Fig. Figure 5 shows a schematic representation of a phased array 102 from the Fig. Figures 1 to 4 show an idealized representation of the emitter elements 104 as spherical wave emitters.

[0056] Fig. Figure 6 shows diagrams illustrating a phase profile 600, emitter apertures 602 in the amplitude profile, and a far-field intensity 604 of a phased array from the Fig. Figures 1 to 5 show the modeling and simulation of a one-dimensional array with an idealized representation of the emitters as rectangular apertures. At constant phase, constructive interference in the far field results in an intensity maximum in the zeroth diffraction order.

[0057] Fig. Figure 7 shows diagrams illustrating a phase profile 700, emitter apertures 702 in the amplitude profile, and a far-field intensity 704 of a phased array from the Fig. 1 to 5. It can be seen that a linear phase profile causes an offset in the far-field intensity profile.

[0058] Fig. Figure 8 shows diagrams for representing a phase profile 800, emitter apertures 802 in the amplitude profile and a far-field intensity 804 of a phased array from the Fig. 1 to 5.

[0059] Fig. Figure 9 shows diagrams illustrating an amplitude of 900 and a far-field intensity of 902 of a phased array from the Fig. 1 to 5. A position of the zeroth diffraction order is indicated by a marker cross.

[0060] Fig. 10 shows analogous to Fig. 9 diagrams illustrating an amplitude of 1000 and a far-field intensity of 1002 of a phased array from the Fig. 1 to 5.

[0061] Fig. Figure 11 shows diagrams representing an amplitude (1100), a phase (1102), and a far-field intensity (1104) of a phased array from the Fig. 1 to 5.

[0062] Fig. Figure 12 shows diagrams representing an amplitude (1200), a phase (1202), and a far-field intensity (1204) of a phased array from the Fig. 1 to 5.

[0063] Fig. Figure 13 shows a diagram illustrating a far field 1300 of a horizontal phased array according to an exemplary embodiment. Also shown is a spatially dependent amplitude profile 1304 associated with the far field 1300.

[0064] Fig. Figure 14 shows a diagram illustrating a far field 1400 of a vertical phased array according to an embodiment. Also shown is a spatially dependent amplitude profile 1402 associated with the far field 1400.

[0065] Fig. Figure 15 shows a flowchart of a method 1500 for multidimensional beam shaping according to an exemplary embodiment, for example by means of the previously described method. Fig. The beam shaping module described in sections 1 to 5 comprises a step 1510 in which the radiation provided with the phase profile by the phased arrays is emitted. In a further step 1520, the emitted radiation is deflected in a suitable direction to achieve multidimensional beam shaping or deflection.

[0066] Fig. Figure 16 shows a flowchart of a method 1600 for controlling a beam shaping module, such as the one described above. Fig. The beam shaping module described in sections 1 to 5. Method 1600 comprises a step 1610 in which a first control signal is output to control the array and / or the deflection element, and a second control signal is output to control the further array and / or the further deflection element. Appropriate control ensures that different angular ranges of a space surrounding the beam shaping module are illuminated simultaneously.

[0067] Fig. Figure 17 shows a flowchart of a process 1700 for manufacturing a beam shaping module, such as the one described above. Fig. The beam shaping module described in sections 1 to 5 includes an optional step (1710) in which the phased array and the deflection element are formed. In a further step (1720), the array is combined with the deflection element, with the deflection element being placed downstream of the array.

[0068] Fig. Figure 18 shows a schematic representation of a device 1800 according to an exemplary embodiment. The device 1800 can, for example, perform the previously described function by means of Fig. The device 1800 includes a control unit 1810 for outputting the first control signal 1812 and the second control signal 1814.

[0069] Fig. Figure 19 shows a schematic representation of a lidar system 1900 according to an exemplary embodiment. The lidar system 1900, which serves, for example, as an environmental sensor in a motor vehicle, comprises at least one beam shaping module 100, as previously described in the Fig. 1 to 18 are described.

[0070] The following is a summary of various implementation examples of the approach presented here, using different words.

[0071] According to one embodiment, the beam shaping module 100 consists of an arrangement of one-dimensional optical phase-controlled arrays 102, 110, each followed by a deflection element 108, 116, which enables the deflection of the light in the transverse axis perpendicular to the deflection direction of the respective arrays. The deflection is carried out statically with fixed angles or dynamically with programmable deflection elements.

[0072] According to one embodiment, the phase-controlled arrays 102, 110 are based on integrated optical components for waveguides, phase shifters, and emitters. Optionally, collimating optics, particularly for the non-phase-modulated axis, are integrated or downstream, for example, to reduce the divergence in this axis, as described in Fig. 2 is shown as an example.

[0073] According to one embodiment, the deflection in the second dimension is achieved via refractive surfaces such as prisms.

[0074] Additionally or alternatively, deflection in the second dimension occurs via reflective surfaces.

[0075] It is particularly advantageous if the deflection in the second dimension is achieved via diffractive surfaces, for example blaze grids, diffractive optical elements or holographic-optical elements.

[0076] According to one embodiment, the deflection in the second dimension is achieved via adaptive optical components such as area light modulators, also called spatial light modulators or SLMs for short, switchable holographic elements or similar.

[0077] According to one embodiment, the beam shaping module 100 has several OPA channels for simultaneously illuminating different angular ranges.

[0078] The OPA channels are used, for example, to simultaneously illuminate overlapping angular areas. This increases the intensity and thus the expected range.

[0079] For example, it is also possible to superimpose different interference patterns with overlapping intensity ranges to generate different intensity levels. This is helpful, for instance, to increase the overall diffraction efficiency of the combined system in the deflected beam within certain angular ranges, since this efficiency typically decreases for larger deflection angles, for example, due to sinc modulation in the far field or, more generally, due to the element factor of the individual emitters. Therefore, it is advantageous if, at large deflection angles, several of the arrays 102 and 110 are deflected simultaneously in the corresponding direction, so that the individual far-field intensities superimpose incoherently and thereby increase the total intensity emitted within a given angular range.

[0080] According to one embodiment, the various OPA channels are arranged in different orientations, for example, orthogonally to each other. This allows the advantages of OPA beam shaping to be utilized over a wider angular range.

[0081] Optionally, a matrix arrangement of two-dimensional arrays is also possible to extend the flexibility and resolution in an angular range defined by a single array by combining them over a larger angular range.

[0082] According to a particularly advantageous embodiment with at least two arrays arranged perpendicular to each other, it is possible to superimpose different interference patterns with overlapping intensity ranges. This allows different intensity levels to be superimposed incoherently. As already described, this makes it possible to increase the overall diffraction efficiency of the combined system in the deflected beam within certain angular ranges, since this efficiency typically decreases for larger deflection angles, for example due to sinc modulation in the far field or, more generally, due to the element factor of the individual emitters.

[0083] The particular advantage of using arrays arranged perpendicular to each other is that the stray light is not amplified as much as in the case of parallel arrays, which may have identical phase profiles. This is because the higher orders are generated on mutually perpendicular axes, and therefore the stray light level cannot increase due to incoherently superimposed higher orders. The contrast relative to the higher orders can even be improved in this case. However, this requires that the far-field divergence in the short array axes is reduced, for example, by means of collimation optics.

[0084] If an embodiment includes an “and / or” connection between a first feature and a second feature, this is to be read as meaning that the embodiment according to one embodiment has both the first feature and the second feature, and according to another embodiment either only the first feature or only the second feature.

Claims

[1] Beam shaping module (100) for multidimensional beam shaping, wherein the beam shaping module (100) has the following features: at least a phase-controlled array (102) with a plurality of emitter elements (104) for generating electromagnetic radiation and at least one phase-shifting element (106) for imprinting a defined phase profile onto the radiation; and at least one deflection element (108) downstream of the array (102) for deflecting emission radiation emitted by the array (102) and having the phase profile in a deflection direction that differs from an emission direction of the emission radiation. [2] Beam shaping module (100) according to claim 1, wherein the array (102) has a plurality of emission surfaces each associated with an emitter element (104) for emitting the emission radiation, wherein the emission surfaces are arranged at a defined distance from one another to form a one-dimensional array (102). [3] Beam shaping module (100) according to one of the preceding claims, wherein the deflection element (108) is designed to deflect the emission radiation in a deflection direction orthogonal to the emission direction and / or in different deflection directions. [4] Beam shaping module (100) according to one of the preceding claims, wherein the deflection element (108) comprises a refractive and / or reflective and / or diffractive surface and / or a diffractive optical element and / or a holographic optical element and / or a surface light modulator and / or a prism and / or a diffraction grating. [5] Beam shaping module (100) according to one of the preceding claims, comprising a collimation element (200) connected between the array (102) and the deflection element (108) for collimating the emission radiation, wherein the deflection element (108) is configured to deflect emission radiation collimated by the collimation element (200). [6] Beam shaping module (100) according to one of the preceding claims, comprising at least one further phase-controlled array (110; 300) with a plurality of further emitter elements (112) for generating further electromagnetic radiation and at least one further phase shifter element (114) for imprinting a further defined phase profile onto the further radiation and at least one further deflection element (116; 302) downstream of the further array (110; 300) for deflecting further emission radiation emitted by the further array (110; 300) and having the further phase profile into a further deflection direction that differs from a further emission direction of the further emission radiation. [7] Beam shaping module (100) according to claim 6, wherein the array (102) and the further array (110; 300) are aligned perpendicular to each other and / or stacked on top of each other and / or connected to form an array assembly. [8] Lidar system (1900) comprising at least one beam shaping module (100) according to any one of the preceding claims. [9] Method (1500) for multidimensional beam shaping using a beam shaping module (100) according to any one of claims 1 to 7, wherein the method (1500) comprises the following steps: Emitting (1510) the emission radiation in the direction of emission; and Deflection (1520) of the emission radiation in the direction of deflection in order to achieve multidimensional beam shaping. [10] Method (1600) for controlling a beam shaping module (100) according to claim 6 or 7, wherein the method (1600) comprises the following step: Output (1610) of a first control signal (1812) to control the array (102) and / or the deflection element (108) and a second control signal (1814) to control the further array (110; 300) and / or the further deflection element (116; 302) to illuminate different angular ranges of a space surrounding the steel forming module (100) simultaneously. [11] Method (1600) according to claim 10, wherein in the output step (1610) the first control signal (1812) and the second control signal (1814) are output to simultaneously illuminate at least partially overlapping angular ranges and / or to superimpose different interference patterns. [12] Method (1700) for producing a beam shaping module (100) according to any one of claims 1 to 7, wherein the method (1700) comprises the following step: Combining (1720) the array (102) with the deflection element (108) such that the deflection element (108) is downstream of the array (102) to produce the beam shaping module (100). [13] Device (1800) comprising a unit (1810) configured to perform and / or control the method (1600) according to claim 10 or 11. [14] Computer program configured to execute and / or control the method (1600) according to claim 10 or 11. [15] Machine-readable storage medium on which the computer program according to claim 14 is stored.

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