Object tracking and / or object recognition device and object tracking and / or object recognition method

Abstract

The invention relates to an object tracking and / or object recognition device (60a-d) at least for non-contact detection of relative location changes and / or speeds of an object (10a-d) and / or for non-contact differentiation of differently shaped objects (10a-d), comprising a laser feedback interferometry (LFI) sensor unit (12a-d). According to the invention, the LFI sensor unit (12a-d) has at least one surface emitter (VCSEL) (14a-d) with at least one integrated photodiode (ViP) (16a-d), said at least one surface emitter forming a plurality of integrated mesas (18a-b, 20b, 22a-d) which each constitute sensor laser beam sources.

Description

[0001] R.416794

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[0003] Description

[0004] Object tracking and / or object detection device and object tracking and / or object detection method

[0005] State of the art

[0006] An object tracking and / or object detection device has already been proposed, at least for the non-contact detection of relative changes in position and / or speed of an object using a laser feedback interferometry (LFI) sensor unit.

[0007] To track general movements using the measurement method of a static laser feedback interferometer, multiple measurement points / laser points are often projected onto a target. These points are generated by several VCSELs, each with integrated photodiodes. The higher the number of measurement points / laser points, the more robust the system. However, large 2D arrays of LFI sensors, capable of covering a sufficiently large area, can have disadvantages regarding space requirements, power consumption, weight, design complexity, cost, and / or eye safety (increased overall optical power).

[0008] Disclosure of the invention

[0009] The invention relates to an object tracking and / or object recognition device for at least non-contact detection of relative changes in position and / or speed of an object and / or non-contact differentiation of differently shaped objects, with a laser feedback interferometry (LFI) sensor unit. R.416794

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[0011] It is proposed that the LFI sensor unit comprises at least one surface emitter (VCSEL) with at least one integrated photodiode (ViP), which forms a plurality of integrated mesas, each representing a sensor laser beam source. This avoids the aforementioned disadvantages and preferably offers advantages regarding space requirements, power consumption, weight, design complexity, cost, and / or eye safety. The object tracking and / or object recognition device can be used, in particular, to track one eye of a user of smart glasses. However, tracking other objects in space using the object tracking and / or object recognition device is also conceivable. The LFI sensor unit is based on an interferometric measurement method, also known as laser self-mixing.In particular, at least some of the mesas of the LFI sensor unit emit a (coherent) laser beam in the infrared spectrum, which then strikes a reflecting surface (e.g., a person, an eye, etc.). From this surface, the laser beam's light is backscattered, re-entering a laser cavity (the emitting laser cavity) of the LFI sensor unit's laser source. Within the laser cavity, the backscattered light interferes with a locally oscillating field of the emitted laser beam. This, in particular, modulates the laser power of the source, which can optionally be detected by the photodiode. The photodiode can be a photodetector integrated into a back reflector of the laser cavity or a measuring device that directly measures the voltage of the laser source.

[0012] The LFI sensor unit preferably comprises an infrared laser source (designed as one of the integrated mesas) with the laser cavity. The infrared laser source of the LFI sensor unit is, in particular, an infrared laser diode. From measurement signals of the LFI sensor unit, the distance of the reflecting object and / or the velocity of a reflecting object moving parallel to a propagation direction of the laser beam of the LFI sensor unit can be determined in a known manner. Furthermore, the direction vector of a movement of the moving reflected object can also be determined using the LFI sensor unit in a known manner. (From Zusam-R.416794)

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[0014] Object recognition can be performed by comparing several velocities and / or distances determined in this way at different points on the object. In this context, an integrated mesa is preferably a mesa structure that is functionally integrated into a larger semiconductor device or system. Preferably, the integrated mesa is a specific structure that is produced during the fabrication of the LFI sensor unit on a common substrate, for example, on a common semiconductor substrate with other integrated mesas of the LFI sensor unit. The integrated mesa can be a real mesa, for example, a laser light-generating structure that is formed as a raised, table-like (mesa-like) region that has been machined from the substrate by selective etching or other fabrication processes.The integrated mesa can be a virtual mesa, which in particular does not itself generate laser light, but deflects laser light from another real mesa. The virtual integrated mesas are also preferably machined from the substrate or applied to / attached to the substrate.

[0015] If at least one of the integrated mesas is a virtual mesa without its own laser-active region, advantages can be achieved, particularly regarding weight reduction, complexity reduction, power consumption reduction, and / or cost reduction. A laser-active region is, in particular, a laser beam-generating active region of the LFI sensor unit. The virtual mesa is, in particular, a region of the LFI sensor unit that is arranged at least substantially in the same plane as one or more laser-active / laser beam-generating regions of the LFI sensor unit and is designed to reflect at least part of a laser beam generated elsewhere by the LFI sensor unit as if it originated from its own real mesa of the LFI sensor unit. The LFI sensor unit can have multiple virtual mesas.In particular, all virtual mesas of the LFI sensor unit are arranged in a common plane and preferably form a virtual mesa array. In particular, the virtual mesa possesses only a beam deflection and / or beam shaping function. In particular, the virtual mesa does not need to have a geometric mesa-like (table-like) structure. In particular, the virtual mesa can be defined by a (at least one real mesa) element. (R.416794)

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[0017] de) optical element embedded in the semiconductor substrate of the LFI sensor unit or placed on the semiconductor substrate of the LFI sensor unit (comprising at least one real mesa).

[0018] Furthermore, if at least one of the integrated mesas is a real mesa with its own laser-active area, and the virtual mesa generates its assigned sensor laser beam from a portion of the laser light produced by the real mesa, advantages can be achieved, particularly with regard to weight reduction, complexity reduction, power consumption reduction, and / or cost reduction. Advantageously, compared to a 2D laser array, a portion of the laser light sources can be omitted, especially without any loss of resolution. Preferably, different real mesas can be controlled individually and / or separately. In particular, the sensor laser beam emitted by the virtual mesa is a reflection of a portion of the total light signal / laser light emitted by the real mesa.A further portion of the total light signal / laser light emitted by the real mesa, which was not deflected towards the virtual mesa, preferably forms the sensor laser beam emitted by the real mesa. In particular, the LFI sensor unit comprises a plurality of real mesas and / or a plurality of virtual mesas. Specifically, each virtual mesa is assigned at least one, preferably exactly one, real mesa, which transfers a portion of its laser light to the virtual mesa. Each real mesa, preferably each real mesa, can be assigned exactly one virtual mesa, exactly two virtual mesas, or a different number of mesas, which may also be greater than two. The laser-active area is, in particular, a laser cavity.

[0019] If at least one of the integrated mesas is a second virtual mesa, distinct from the virtual mesa and spatially separated from it, without its own laser-active area, and if the second virtual mesa generates its assigned sensor laser beam from a further portion of the laser light produced by the real mesa, then the aforementioned advantages regarding weight reduction, complexity reduction, power consumption reduction, and / or cost reduction can be further enhanced. It is particularly conceivable that one of the integrated Me-R.416794

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[0021] This is a third virtual mesa, distinct from the first and second virtual mesa, and spatially separated from the first and second virtual mesa, without its own laser-active area. The third virtual mesa generates its assigned sensor laser beam from a further portion of the laser light produced by the real mesa. It is also conceivable to have more than three virtual mesas assigned to the real mesa and supplied with a portion of the real mesa's laser light.

[0022] Furthermore, it is proposed that the virtual mesa be formed by an optical reflection element, particularly an integrated one, specifically a reflective surface layer, a diffractive optical element (DOE) with at least reflective properties, a holographic optical element (HOE) with at least reflective properties, or a meta-optic element (MOE) with at least reflective properties. This advantageously allows for a simple, lightweight, compact, and / or cost-effective design. Preferably, the optical reflection element is integrated into or directly connected to the same semiconductor substrate as the real mesa.

[0023] Furthermore, it is proposed that the LFI sensor unit comprises an optical unit arranged in a beam path of at least one of the sensor laser beams generated by one of the sensor laser beam sources, preferably in beam paths of several / all sensor laser beams generated by the sensor laser beam sources, and which has at least one optically active area configured to partially reflect and partially transmit laser light from one of the integrated mesas, which is configured as a real mesa with its own laser-active area, particularly towards one or more of the integrated mesas, which are configured as virtual mesas without their own laser-active area. This advantageously allows for a simple, lightweight, compact, and / or cost-effective design. The optical unit can be a combined optical element or comprise several separate optical sub-elements.Preferably, a portion of the laser light transmitted by the optical unit to the real mesa forms the sensor laser beam or beams of the real mesa. Preferably, a portion of the laser light reflected by the optical unit to one of the virtual mesas is reflected again by the virtual mesa and subsequently forms the R.416794.

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[0025] The sensor laser beam of the virtual mesa is emitted. "Designed" and / or "configured" are understood to mean, in particular, specifically programmed, designed, and / or equipped. The fact that an object is designed and / or configured for a specific function is understood to mean, in particular, that the object fulfills and / or performs this specific function in at least one application and / or operating state. The optical unit may, in particular, comprise one or more reflective surface layers, one or more DOEs, one or more HOEs, or one or more MOEs for generating a transmission, reflection, and / or beam-shaping function. These optical elements of the optical unit may be at least partially integrated into a common element, applied to a common element, and / or at least partially formed by several individual elements positioned relative to one another.

[0026] If at least one optically active area of ​​the optical unit is configured to transform the transmitted portion of the laser light from the real mesa into a beam pattern generating multiple measurement points, the advantages in terms of simplicity, lightness, compact design, energy efficiency, and / or cost-effectiveness can be further enhanced. In particular, the at least one optically active area of ​​the optical unit has an optical function configured to split incident and transmitted laser light into multiple partial beams, each deflected in different directions. The beam pattern can have various shapes, such as a matrix, a quincunx, a circle, a zigzag, etc.

[0027] Furthermore, it is proposed that the optical unit has a further optically active area, distinct from the at least one optically active area and in particular spatially separated, which is configured to transmit at least a large part of the sensor laser beam of the virtual mesa and thereby transform it into a beam pattern generating multiple measurement points and / or deflect it in a beam direction which is angled and / or non-parallel to a beam direction of the portion of the sensor laser beam of the real mesa that is transmitted through the optically active area.

[0028] This allows for advantageous, reliable and / or simple signal separation of R.416794.

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[0030] Measurement signals from the various sensor laser beams can be obtained, particularly since each sensor laser beam has a different optical path length. Advantageously, this allows the beat frequencies of the different signals to be reliably distinguished within an intensity-distance space. The device's internal path lengths and / or deflection angles of the sensor laser beams relative to each other are known and can advantageously be calculated after the measurement signals have been distinguished. If different sensor laser beams strike an object at different angles, the determined distance signals of these sensor laser beams will exhibit different temporal slopes, especially when the object is moved relative to the LFI sensor unit.This is primarily due to the fact that the respective optical path lengths to the object change differently depending on the different angles of the sensor laser beams to the direction of movement of the object.

[0031] Furthermore, if optically active areas of the optical unit, each designed to transmit sensor laser beams from different sensor laser sources configured as integrated mesas, are equipped with significantly different transmission efficiencies, the assignment of measurement signals to individual sensor laser beams can be further optimized. In particular, in addition to the different optical path lengths and the different temporal slopes of the optical path lengths during object movement, known differences in intensities can be taken into account to identify the measurement signals belonging to specific sensor laser beams.For example, individual measurement points of a measurement point pattern originating from laser light of the same real mesa, or sensor laser beams from virtual mesas divided into multiple measurement points, can be provided with clearly different intensities via the different transmission efficiencies for the respective measurement points.

[0032] Alternatively or additionally, it is proposed that optically active areas of the optical unit, each intended to transmit sensor laser beams from different sensor laser beam sources configured as integrated mesas, be designed to generate significantly different beam patterns, each providing multiple measurement points. R.416794

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[0034] This can also facilitate the re-identification of measurement signals, e.g. from different real-world measuring devices.

[0035] Furthermore, it is proposed that the optical unit, in particular a combined optical element forming the optical unit or one or more optical sub-elements of the optical unit, is arranged at an angle relative to a common emission plane of the sensor laser beam sources formed by the integrated mesas, and / or that one or more tilts are encoded in one or more optical functions of the optical unit, in particular the combined optical element or the optical sub-element(s) of the optical unit. This advantageously allows different distance measurements to be enforced, which permits the measurement signals to be assigned to individual sensor laser beams. Subsequently, the effect of the known tilt can be factored out for object tracking and / or detection.

[0036] Furthermore, it is proposed that a measurement range of one of the at least one integrated photodiodes of the LFI sensor unit, in particular the single integrated photodiode of the LFI sensor unit, be jointly assigned to more than one integrated (real and / or virtual) mesa, preferably to all integrated (real and / or virtual) mesas of the LFI sensor unit. This allows for advantages in terms of space requirements, power consumption, weight, design effort, and / or cost. In particular, the integrated photodiode can be placed below the mesas, in particular only the real mesas, of the LFI sensor unit. In particular, if the (real) mesas are now addressed / activated sequentially, each readout of the photodiode can be assigned to one of these mesas and to the sensor laser beams associated with that mesa (from the real mesa and the virtual mesas supplied by that real mesa).

[0037] Alternatively or additionally, it is proposed that at least two of the integrated mesas of the LFI sensor unit, and in particular each of the integrated mesas of the LFI sensor unit, be individually assigned a different integrated photodiode of the VCSEL. This would allow at least these mesas to be pre-R.416794

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[0039] They can be operated partially in parallel. This allows for a higher temporal resolution, which is advantageous.

[0040] Furthermore, an object tracking and / or object recognition method, in particular using the object tracking and / or object recognition device, is proposed for at least the non-contact detection of relative changes in position and / or velocity of an object and / or for the non-contact differentiation of differently shaped objects, using the laser feedback interferometry (LFI) sensor unit, wherein the sensor laser beams of the LFI sensor unit are generated by the at least one surface emitter (VCSEL) with the at least one integrated photodiode, which forms the plurality of integrated mesas, each representing the sensor laser beam sources. This preferably allows for advantages with regard to space requirements, power consumption, weight, design complexity, costs, and / or eye safety.

[0041] The object tracking and / or object recognition device and the object tracking and / or object recognition method according to the invention are not to be limited to the application and embodiment described above. In particular, the object tracking and / or object recognition device and the object tracking and / or object recognition method according to the invention may, in order to fulfill a functionality described herein, have a different number of individual elements, components, units, and process steps than that specified herein. Furthermore, values ​​within the specified limits of the value ranges stated in this disclosure are also to be considered disclosed and freely usable.

[0042] drawing

[0043] Further advantages will become apparent from the following drawing description. The drawing illustrates four embodiments of the invention. The drawing, the description, and the claims contain numerous features in R.416794.

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[0045] Combination. The expert will expediently consider the features individually and combine them into meaningful further combinations.

[0046] They show:

[0047] Fig. 1a shows a schematic representation of an object tracking and / or object recognition device with an LFI sensor unit.

[0048] Fig. 1b shows an exemplary measurement signal of the object tracking and / or object recognition device from Figure 1a in an intensity-distance diagram.

[0049] Fig. 1c shows an exemplary change in the positions of signal peaks of the measurement signal on a distance axis in a distance-time diagram.

[0050] Fig. 2 a schematic flowchart of an object tracking and / or object recognition method using the object tracking and / or object recognition device, Fig. 3a a schematic representation of an alternative object tracking and / or object recognition device with an alternative LFI sensor unit,

[0051] Fig. 3b shows an exemplary measurement signal of the alternative object tracking and / or object recognition device from Figure 3a in an intensity-distance diagram,

[0052] Fig. 4 shows a schematic representation of a second alternative object tracking and / or object detection device with a second alternative LFI sensor unit,

[0053] Fig. 5a shows a schematic representation of a third alternative object tracking and / or object detection device with a third alternative LFI sensor unit and

[0054] Fig. 5b shows an exemplary measurement signal of the third alternative object tracking and / or object recognition device from Figure 5a in an intensity-distance diagram.

[0055] Description of the exemplary embodiments R.416794

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[0057] Figure 1a schematically shows an object tracking and / or object detection device 60a. The object tracking and / or object detection device 60a is designed for non-contact detection of relative changes in position and / or velocities of an object 10a. The object tracking and / or object detection device 60a is designed for non-contact differentiation between objects 10a of different shapes. The object tracking and / or object detection device 60a includes a laser feedback interferometry (LFI) sensor unit 12a. The LFI sensor unit 12a includes a surface emitter (VCSEL) 14a. The surface emitter 14a comprises an integrated photodiode (ViP) 16a. The surface emitter 14a includes a plurality of sensor laser beam sources. The sensor laser beam sources of the surface emitter 14a together generate a plurality of sensor laser beams 24a, 48a, each of which is directed onto the object 10a.Object 10a reflects the sensor laser beams 24a and 48a. Parts of these reflection signals are detected by photodiode 16a and assigned to the respective sensor laser beams 24a and 48a. Based on the detected and assigned reflection signals, a processing unit (not shown) can determine the relative changes in position and / or velocities of object 10a. Figure 1a shows object 10a in two different positions at two different times t=1 and t=0. Between these two times, object 10a was moved by a distance A. Based on the detected and assigned reflection signals, the processing unit (not shown) can determine / estimate the surface shape of object 10a and, based on this, identify object 10a.

[0058] The surface emitter 14a comprises a plurality of integrated mesas 18a, 22a. In the example shown in Figure 1a, two integrated mesas 18a, 22a are depicted. Of course, the surface emitter 14a can also comprise more than two integrated mesas 18a, 22a. It is also conceivable that the object tracking and / or object detection device 60a comprises several surface emitters 14a with integrated photodiodes 16a and each with several integrated mesas 18a, 22a. The sensor laser beam sources are formed by the integrated mesas 18a, 22a. The integrated mesas 18a, 22a each form one or more of the sensor laser beam sources. R.416794

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[0060] A first integrated mesa 22a of the two integrated mesas 18a, 22a shown by way of example in Fig. 1a is a real mesa 22a with its own laser-active area. The laser-active area of ​​the real mesa 22a comprises a laser cavity. The laser-active area of ​​the real mesa 22a generates laser light 26a. The real mesa 22a emits the laser light 26a in the direction of the object 10a. The real mesa 22a has a geometric mesa-like structural elevation. A second integrated mesa 18a of the two integrated mesas 18a, 22a shown by way of example in Fig. 1a is a virtual mesa 18a. The virtual mesa 18a does not comprise a laser-active area. The virtual mesa 18a is not capable of generating laser light 26a itself. The virtual mesa 18a does not exhibit any geometric mesa-like structural elevation. The virtual mesa 18a is formed by an optical reflection element 30a.The optical reflection element 30a is integrated into the surface emitter 14a or applied to a surface of the surface emitter 14a. The optical reflection element 30a could be configured as a reflective surface layer, as a diffractive optical element (DOE) with at least reflective properties, as a holographic optical element (HOE) with at least reflective properties, or as a meta-optic element (MOE) with at least reflective properties. The virtual mesa 18a is designed to generate its associated sensor laser beam 24a from a portion of the laser light 26a generated by the real mesa 22a. The virtual mesa 18a is designed to generate its associated sensor laser beam 24a by reflecting a portion of the laser light 26a generated by the real mesa 22a.

[0061] The LFI sensor unit 12a includes an optical unit 52a. The optical unit 52a could alternatively be designed and / or arranged separately from the LFI sensor unit 12a. The optical unit 52a is arranged in a beam path of the laser light 26a generated by the real mesa 22a. The optical unit 52a is arranged in a beam path of the sensor laser beam 24a reflected by the virtual mesa 18a. The optical unit 52a is arranged in the beam paths of all sensor laser beams 24a generated by the sensor laser beam sources of the LFI sensor unit 12a. The optical unit 52a can be designed as a carrier element for several optical elements with respective optically active areas 34a, 50a. The optical unit 52a could also be R.416794

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[0063] The optical unit 52a has several integrated optically active areas 34a and 50a. The optical unit 52a has an optically active area 34a configured to partially reflect and partially transmit laser light 26a generated by the real mesa 22a with its own laser-active area. The optically active area 34a of the optical unit 52a is configured to reflect the portion of the laser light 26a from the real mesa 22a reflected by it towards the virtual mesa 18a, which does not have its own laser-active area. For this purpose, the optically active area 34a has a partially reflective first optical function / element 62a. The virtual mesa 18a then generates its sensor laser beam 24a by reflecting the portion of the laser light 26a from the real mesa 22a reflected to it towards the object 10a and / or the optical unit 52a.The optically active area 34a of the optical unit 52a is configured to direct the portion of the laser light 26a from the real mesa 22a transmitted through it towards the object 10a. For this purpose, the optically active area 34a can have a collimating or focusing second optical function / a collimating or focusing second optical element 64a. The portion of the laser light 26a from the real mesa 22a transmitted directly through the optically active area 34a then forms the sensor laser beam 48a of the real mesa 22a.

[0064] The optical unit 52a has a further optically active area 50a. The further optically active area 50a is distinct from the optically active area 34a. The further optically active area 50a is spatially separated from the optically active area 34a within the optical unit 52a. The further optically active area 50a is configured to transmit the sensor laser beam 24a of the virtual mesa 18a (i.e., the portion of the laser light 26a of the real mesa 22a that has previously been reflected twice by the optically active area 34a and by the optical reflection element 30a of the virtual mesa 18a). The further optically active area 50a is designed to deflect the sensor laser beam 24a during transmission into a beam direction 44a which is angled and / or non-parallel to a beam direction 46a of the portion of the sensor laser beam 48a of the real mesa 22a that is transmitted through the optically active area 34a.In addition, the optical unit 52a in the further optically active area 50a includes one or more further optical functions / further optical elements 66a.R.416794.

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[0066] Figure 1b shows an exemplary measurement signal of the object tracking and / or object recognition device 60a from Figure 1a in an intensity-distance diagram 68a (e.g., at time t = 0). In the intensity-distance diagram 68a, a first signal peak 70a and a second signal peak 72a can be identified. Each of the signal peaks 70a, 72a (beat frequencies) originates from a reflection of one of the sensor laser beams 24a, 48a at the object 10a. The first signal peak 70a belongs to the sensor laser beam 48a of the real mesa 22a. The second signal peak 72a belongs to the sensor laser beam 24a of the virtual mesa 18a. The two signal peaks 70a, 72a are spaced apart from each other on a distance axis of the intensity-distance diagram 68a.Since the sensor laser beam 24a (and its reflection signal) of the virtual mesa 18a traverses a significantly higher signal path due to at least two reflections than the sensor laser beam 48a (and its reflection signal) of the real mesa 22a, its signal peak 72a is found at greater distances on the distance axis of the intensity-distance diagram 68a than the signal peak 70a of the sensor laser beam 48a of the real mesa 22a. Thus, the two signal peaks 70a and 72a can be assigned and evaluated separately. Preferably, the object tracking and / or object recognition device 60a includes the (not shown) computing unit for performing the indicated computer-based evaluations required for detecting relative changes in position and / or velocities and / or object differentiation.

[0067] Figure 1c shows an example of the change in the positions of signal peaks 70a and 72a on the distance axis in a distance-time diagram 74a, which has the same distance axis as the intensity-distance diagram 68a of Figure 1b. On one time axis of the distance-time diagram 74a, the times t = 0 and t = 1 are indicated, at which the object 10a assumes the exemplary positions shown in Figure 1a. Only the maxima of signal peaks 70a and 72a are plotted on another distance axis of the distance-time diagram 74a. It can be seen that the maxima of signal peaks 70a and 72a move differently on the distance axis. A distance value of the maximum of the signal peak 70a, which belongs to the sensor laser beam 48a of the real mesa 22a, increases less sharply with the same movement of the object 10a than an R.416794

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[0069] Distance value of the maximum of signal peak 72a, which belongs to the sensor laser beam 24a of the virtual mesa 18. The reason for this is that the sensor laser beam 24a of the virtual mesa 18a is directed at object 10a at an oblique angle (generated by the optical element 66a), while the sensor laser beam 48a of the real mesa 22a in the illustrated example strikes object 10a at least substantially perpendicularly (i.e., at least at a different angle than the sensor laser beam 24a of the virtual mesa 18a). Thus, the sensor laser beam 24a (and its reflection signal) of the virtual mesa 18a, which is directed at object 10a at the oblique angle, must cover a rapidly increasing distance before being measured by the photodiode 16a than the sensor laser beam 48a of the real mesa 22a.Thus, another feature can be obtained by which the two signal peaks 70a, 72a can be assigned and evaluated separately, namely the slope of the movement of the maxima of the signal peaks 70a, 72a in the distance-time diagram 74a.

[0070] Figure 2 shows a schematic flowchart of an object tracking and / or object recognition method for the non-contact detection of the relative changes in position and / or velocities of object 10a and / or for the non-contact differentiation of differently shaped objects 10a using the object tracking and / or object recognition device 60a comprising the LFI sensor unit 12a. In at least one process step 76a, the sensor laser beams 24a, 48a of the LFI sensor unit 12a-d are generated by the surface emitter 14a with the plurality of integrated mesas 18a, 22a, each of which represents a sensor laser beam source. For this purpose, the laser light 26a is first generated by the actual mesa 22a. A portion of the laser light 26a is then transmitted by the optical unit 52a and directed towards the object 10a. This part forms the sensor laser beam 48a of the real Mesa 22a.Another part of the laser light 26a is not transmitted, but is reflected back by the optical unit 52a towards the optical reflection element 30a. From the optical reflection element 30a, which forms the virtual mesa 18a, this part of the laser light 26a is then reflected back to the optical unit 52a. This part forms the sensor laser beam 24a of the virtual mesa 18a. The optical unit 52a transmits the sensor laser beam 24a and aligns it towards the object 10a. In at least one further method R.416794.

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[0072] In step 78a, the sensor laser beams 24a, 48a are reflected by the object 10a and travel via the reverse optical path into the laser cavity of the surface emitter 14a and into the photodiode 16a of the surface emitter 14a. In at least one further process step 80a, the reflection signals are acquired by the photodiode 16a. In at least one further process step 82a, the reflection signals are separated and assigned to the individual sensor laser beams 24a, 48a / integrated mesas 18a, 22a. In at least one further process step 84a, the position and / or velocity of the object 10a for object tracking is determined from the assigned reflection signals using the LFI (Laser Interferometry Feedback) and FMCW (Frequency Modulated Continuous Wave) methods known to those skilled in the art.In at least one alternative or further process step 86a, the shape of the object 10a is determined from the associated reflection signals using the LFI (Laser Interferometry Feedback) and FMCW (Frequency Modulated Continuous Wave) methods known to the person skilled in the art for object recognition.

[0073] Figures 3a to 5b show three further embodiments of the invention. The following descriptions and drawings are essentially limited to the differences between the embodiments, whereby, with regard to identically designated components, particularly those with the same reference numerals, reference may also be made to the drawings and / or the description of the other embodiments, especially Figures 1a to 2. To distinguish the embodiments, the letter "a" is appended to the reference numerals of the embodiment in Figures 1a to 2. In the embodiments of Figures 3a to 5b, the letter "a" is replaced by the letters "b" to "d".

[0074] Figure 3a schematically shows an alternative object tracking and / or object detection device 60b. The alternative object tracking and / or object detection device 60b includes an alternative laser feedback interferometry (LFI) sensor unit 12b. The alternative LFI sensor unit 12b includes a surface emitter 14b. The surface emitter 14b comprises an integrated photodiode 16b. The surface emitter 14b includes a plurality of sensor laser beam sources. The sensor laser beam sources of the surface-R.416794

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[0076] Surface emitters 14b together generate a plurality of sensor laser beams 24b, 28b, 48b, each directed onto an object 10b. The surface emitter 14b comprises a plurality of integrated mesas 18b, 20b, 22b. In the example shown in Figure 3a, three integrated mesas 18b, 20b, 22b are depicted. The sensor laser beam sources are each formed by the integrated mesas 18b, 20b, 22b. A measurement range of the photodiode 16b is assigned to more than one of the integrated mesas 18b, 20b, 22b. The surface emitter 14b comprises another integrated photodiode 16'b. Photodiode 16b and the other photodiode 16'b are each individually assigned to other integrated mesas 18b, 20b, 22b of the surface emitter 14b.

[0077] A first integrated mesa 22b of the two integrated mesas 18b, 20b, 22b shown by way of example in Fig. 3a is a real mesa 22b with its own laser-active region. The laser-active region of the real mesa 22b comprises a laser cavity. The laser-active region of the real mesa 22b generates laser light 26b. A second integrated mesa 18b of the three integrated mesas 18b, 20b, 22b shown by way of example in Fig. 3a is a virtual mesa 18b. A third integrated mesa 20b of the three integrated mesas 18b, 20b, 22b shown by way of example in Fig. 3a is a virtual mesa 20b. The virtual mesas 18b, 20b do not comprise a laser-active region. The virtual mesas 18b and 20b are not capable of generating laser light 26b themselves. The virtual mesas 18b and 20b are each formed by spatially separated optical reflection elements 30b. The virtual mesas 18b and 20b are spatially arranged differently from each other.The first virtual mesa 18b is designed to generate its associated sensor laser beam 24b from a portion of the laser light 26b generated by the real mesa 22b. The second virtual mesa 20b is designed to generate its associated sensor laser beam 28b from another portion of the laser light 26b generated by the real mesa 22b. Virtual mesa 18b and 20b are each designed to generate their respective associated sensor laser beams 24b and 28b, respectively, by reflecting a portion of the laser light 26b generated by the real mesa 22b.

[0078] The alternative LFI sensor unit 12b has an optical unit 52b. The optical unit 52b is in beam paths of the integrated mesas 18b, 20b, 22bR.416794

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[0080] The optical unit 52b has an optically active region 34b, which is configured to partially reflect and partially transmit laser light 26b generated by the real mesa 22b with its own laser-active region. The optically active region 34b of the optical unit 52b is configured to reflect a first part of the portion of the laser light 26b reflected by it from the real mesa 22b towards the first virtual mesa 18b (or its optical reflection element 30b). The optically active region 34b of the optical unit 52b is configured to reflect a second part of the portion of the laser light 26b reflected by it from the real mesa 22b towards the second virtual mesa 20b (or its optical reflection element 30b). In addition, the optically active area 34b has a doubly partially reflective first optical function / a doubly partially reflective first optical element 62b.The virtual mesas 18b and 20b then each generate their respective sensor laser beams 24b and 28b by re-reflecting the respective portions of the laser light 26b from the real mesa 22b reflected towards the object 10b and / or the optical unit 52b. The optically active area 34b of the optical unit 52b is configured to direct the portion of the laser light 26b from the real mesa 22b transmitted through it towards the object 10b. The portion of the laser light 26b from the real mesa 22b transmitted directly through the optically active area 34b forms the sensor laser beam 48b of the real mesa 22b. The optically active area 34b of the optical unit 52b is designed to transform the portion of the laser light 26b transmitted through it from the real mesa 22b into a beam pattern 38b generating several measurement points 36b.The optically active area 34b and further optically active areas 50b of the optical unit 52b, each designed to transmit sensor laser beams 24b, 28b, 48b from different sensor laser beam sources configured as integrated mesas 18b, 20b, 22b, are equipped with significantly different transmission efficiencies (see Fig. 3b). This provides an additional feature by which signal peaks 70b, 70'b, 72b, 72'b of the measurement signals from the photodiode 16b can be assigned to the respective sensor laser beams 24b, 28b, 48b and evaluated separately.

[0081] The optical unit 52b has the further optically active area 50b and an additional further optically active area 90b. The further optical R.416794

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[0083] Active areas 50b and 90b are distinct from the optically active area 34b. The additional optically active areas 50b and 90b are spatially separated from each other and from the optically active area 34b within the optical unit 52b. The additional optically active area 50b is configured to transmit the sensor laser beam 24b of the first virtual mesa 18b (i.e., the portion of the laser light 26b of the real mesa 22b that has been previously reflected twice by the optically active area 34b and the optical reflection element 30b of the first virtual mesa 18b). The additional optically active area 90b is configured to transmit the sensor laser beam 28b of the second virtual mesa 20b (i.e., the portion of the laser light 26b of the real mesa 22b that has previously been reflected twice by the optically active area 34b and the optical reflection element 30b of the second virtual mesa 20b).The further optically active areas 50b, 90b are configured to transform the respective sensor laser beams 24b, 28b during transmission into a (regular) beam pattern 42b that generates multiple measurement points 40b. For this purpose, the optical unit 52b in the further optically active areas 50b, 90b each comprises one or more further optical functions / further optical elements 66b. The further optical elements 66b are each designed to split the sensor light exiting the optical unit 52b into several, preferably focused or collimated, partial beams, each of which generates one of the measurement points 36b.

[0084] Figure 4 schematically shows a second alternative object tracking and / or object detection device 60c. The second alternative object tracking and / or object detection device 60c comprises a second alternative laser feedback interferometry (LFI) sensor unit 12c. The second alternative LFI sensor unit 12c includes a surface emitter 14c. The surface emitter 14c comprises several spatially separated integrated mesas 22c. The integrated mesas 22c are all real mesas 22c. Each real mesa 22c has its own measurement signal, and superpositions or ambiguities in the overall measurement signal can be advantageously avoided. Each of the real mesas 22c can be controlled and / or read out separately from the other real mesas 22c. The second alternative LFI sensor unit 12c comprises an optical unit 52c. The optical unit 52c includes optically active areas 34c.The optical areas 34c are each intended for sensor R.416794.

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[0086] The laser beams 48c from the different sensor laser beam sources, designed as integrated mesas 22c, are to be transmitted. The optical areas 34c are designed to generate significantly different (irregular) beam patterns 56c, each providing multiple measurement points 54c.

[0087] Figure 5a schematically shows a third alternative object tracking and / or object detection device 60d. The third alternative object tracking and / or object detection device 60d comprises a third alternative laser feedback interferometry (LFI) sensor unit 12d. The third alternative LFI sensor unit 12d includes a surface emitter 14d. The surface emitter 14d comprises several spatially separated integrated mesas 22d. The integrated mesas 22d are all real mesas 22d. The third alternative LFI sensor unit 12d comprises an optical unit 52d. The optical unit 52d is shown by way of example as a combined optical element, but could alternatively also be composed of several optical sub-elements.The optical unit 52d, in particular the combined optical element, is tilted relative to a common emission plane 58d of the sensor laser beam sources formed by the integrated mesas 22d. Alternatively, a tilted optical function could also be encoded in the (then untilted) optical unit 52d. A tilt angle 92d is chosen such that the resulting distance measurements can be separated from one another in an intensity-distance diagram 68d (see Fig. 5b) and thus also assigned to the respective sensor laser beams 48d. In the example shown in Figures 5a and 5b, the chosen tilt ensures that the measurement signals of the sensor laser beams 48d labeled S2 and S2' always produce a shorter distance measurement than the measurement signals of the sensor laser beams 48d labeled S1 and S1'.Furthermore, in this case, the measurement signal labeled S2 always exhibits a shorter distance measurement than the measurement signal labeled S2'. The same applies to the measurement signals with the abbreviations S1 and S1'. An initial calibration can be provided to simplify the assignment. Once identified, the measurement signals are permanently distinguishable because the object cannot jump 10d.

Claims

R.416794 - 21 - Claims 1. Object tracking and / or object recognition device (60a-d) for at least non-contact detection of relative changes in position and / or velocities of an object (10a-d) and / or non-contact differentiation of differently shaped objects (10a-d), with a laser feedback interferometry (LFI) sensor unit (12a-d), characterized in that the LFI sensor unit (12a-d) has at least one surface emitter (VCSEL) (14a-d) with at least one integrated photodiode (ViP) (16a-d), which forms a plurality of integrated mesas (18a-b, 20b, 22a-d), each of which represents sensor laser beam sources.

2. Object tracking and / or object recognition device (60a-b) according to claim 1, characterized in that at least one of the integrated mesas (18a-b, 20b, 22a-b) is a virtual mesa (18a-b) without its own laser-active area.

3. Object tracking and / or object recognition device (60a-b) according to claim 2, characterized in that at least one of the integrated mesas (18a-b, 20b, 22a-b) is a real mesa (22a-b) with its own laser-active area, wherein the virtual mesa (18a-b) generates the sensor laser beam (24a-b) assigned to it from a part of a laser light (26a-b) generated by the real mesa (22a-b).

4. Object tracking and / or object recognition device (60b) according to claim 3, characterized in that at least one of the integrated mesas (18b, 20b, 22b) is a second virtual mesa (20b) that is different from and spatially separated from the virtual mesa (18b) and has no laser-active area of ​​its own, wherein the second virtual mesa (20b) provides the sensor laser beam (28b) assigned to it from a further part of the R.416794 - 22 - generated laser light (26b) from real Mesa (22b).

5. Object tracking and / or object recognition device (60a-b) according to one of claims 2 to 4, characterized in that the virtual mesa (18a-b, 20a-b) is formed by an optical reflection element (30a-b), in particular an integrated optical reflection element, in particular a reflective surface layer, a diffractive optical element (DOE) that has at least reflective properties, a holographic optical element (HOE) that has at least reflective properties or a meta-optic element (MOE) that has at least reflective properties.

6. Object tracking and / or object recognition device (60a-d) according to one of the preceding claims, characterized in that the LFI sensor unit (12a-d) comprises an optical unit (52a-d) which is arranged in a beam path of laser light (26a-d) generated by at least one of the sensor laser beam sources, preferably in beam paths of several / all sensor laser beams (24a-b, 28a-b, 48a-d) generated by the sensor laser beam sources, and which has at least one optically active area (34a-d) configured to reflect laser light (26a-d) from one of the integrated mesas (18a-b, 20b, 22a-d), which is configured as a real mesa (22a-d) with its own laser-active area, in particular in the direction of one or more of the integrated mesas (18a-b, 20b, 22a-d), which are configured as virtual mesas (18a-b, 20b) are designed without their own laser-active area to partially reflect and partially transmit.

7. Object tracking and / or object recognition device (60b-d) according to claim 6, characterized in that the at least one optically active area (34b-d) of the optical unit (52b-d) is configured to transform the transmitted portion of the laser light (26a-d) of the real mesa (22b-d) into a beam pattern (38b-d) generating multiple measurement points (36b-d).

8. Object tracking and / or object recognition device (60a-b) according to claim 3 and according to one of claims 6 or 7, characterized by R.416794 - 23 - The optical unit (52a-b) has a further optically active area (50a-b) that is different from, and in particular spatially separated from, the at least one optically active area (34a-b) and is configured to transmit at least a large part of the sensor laser beam (24a-b) of the virtual mesa (18a-b) and thereby transform it into a beam pattern (42b) generating several measurement points (40b) and / or deflect it into a beam direction (44a) which is angled and / or non-parallel to a beam direction (46a) of the portion of the sensor laser beam (48a) of the real mesa (22a) that is transmitted through the optically active area (34a).

9. Object tracking and / or object recognition device (60b) according to one of claims 6 to 8, characterized in that optically active areas (34b, 50b) of the optical unit (52b), which are each provided to transmit sensor laser beams (24b, 28b, 48b) from different sensor laser beam sources designed as integrated mesas (18b, 20b, 22b), are equipped with significantly different transmission efficiencies.

10. Object tracking and / or object recognition device (60c) according to one of claims 6 to 9, characterized in that optically active areas (34c, 50c) of the optical unit (52c), which are each provided to transmit sensor laser beams (48c) from different sensor laser beam sources designed as integrated mesas (22c), are provided to generate beam patterns (56c) that are substantially different and provide several measurement points (54c).

11. Object tracking and / or object recognition device (60d) according to one of claims 6 to 10, characterized in that the optical unit (52d), in particular a combined optical element forming the optical unit (52d) or one or more optical sub-elements of the optical unit (52d), is arranged tilted relative to a common emission plane (58d) of the sensor laser beam sources formed by the integrated mesas (22d), and / or that one or more tilts are incorporated into one or more optical functions of the optical unit (52d). - 24 - unit (52d), in particular the combined optical element or the optical sub-element(s) of the optical unit (52d), are encoded.

12. Object tracking and / or object recognition device (60a-d) according to one of the preceding claims, characterized in that a measuring range of one of the at least one integrated photodiodes (16a-d) of the LFI sensor unit (12a-d), in particular the single integrated photodiode (16a-d) of the LFI sensor unit (12a-d), is jointly assigned to more than one integrated mesa (18a-b, 20b, 22a-d), preferably all integrated mesas (18a-b, 20b, 22a-d) of the LFI sensor unit (12a-d).

13. Object tracking and / or object recognition device (60a-d) according to one of the preceding claims, characterized in that at least two of the integrated mesas (18a-b, 20b, 22a-d) of the LFI sensor unit (12a-d), in particular each of the integrated mesas (18a-b, 20b, 22a-d) of the LFI sensor unit (12a-d), are individually assigned a different integrated photodiode (16a-d, 16'ad) of the surface emitter (14a-d).

14. Object tracking and / or object recognition method, in particular by means of an object tracking and / or object recognition device (60a-d) according to one of the preceding claims, at least for non-contact detection of relative changes in position and / or velocities of an object (10a-d) and / or for non-contact differentiation of differently shaped objects (10a-d), by means of a laser feedback interferometry (LFI) sensor unit (12a-d), characterized in that sensor laser beams (24a-b, 28a-b, 48a-d) of the LFI sensor unit (12a-d) are generated by at least one surface emitter (14a-d) with at least one integrated photodiode (16-d), which forms a plurality of integrated mesas (18a-b, 20b, 22a-d), each of which represents a sensor laser beam source.

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