DE102020214458A1 - Scanning device for emitting light beams from a light source and/or for imaging light beams onto a detector, LiDAR sensor and method for controlling a scanning device - Google Patents

Abstract

The invention relates to a scanning device (10) for emitting light beams from a light source (60) and/or for imaging light beams onto a detector, comprising at least one optical imaging system (20) which is set up to project light incident on one side of the object onto an image shell (30 ) image, and at least one light source (60) and / or at least one detector for detecting light imaged on the detector. Furthermore, it is provided that the at least one light source (60) and/or the at least one detector are mounted on a movable platform (44) of a parallel rocker (40), which is arranged and set up, the at least one light source (60) and/or to move the at least one detector relative to the at least one optical imaging system (20) in such a way that the at least one light source (60) and/or the at least one detector moves along the image tray (30) of the imaging system (20).Further aspects of the The invention relates to a LiDAR sensor that includes such a scanning device (10) and a method for controlling such a scanning device (10).

Description

The invention relates to a scanning device for emitting light beams from a light source and/or for imaging light beams onto a detector, comprising at least one optical imaging system which is set up to image light incident on an object side onto an image shell, and at least one light source and/or at least one Detector for detecting light imaged on the detector.

Further aspects of the invention relate to a LiDAR sensor, which includes such a scanning device, and a method for controlling such a scanning device.

State of the art

Various concepts are known in the prior art for LiDAR (Light Detection And Ranging) sensors. One possibility is the use of so-called “macro scanners”. Here, for example, a rotating macro-mirror has a diameter on the order of a few centimeters. As a result, a light beam with a diameter of this magnitude can also be guided over the mirror. Another possibility is the use of “micro scanners”. Here, small mirrors with a diameter of the order of a few millimeters are used, which are manufactured using MEMS (micro-electro-mechanical systems) technology and are mounted such that they can swing or rotate in one or two axes in order to implement beam deflection. The advantages here are the small size and the lack of macroscopic moving elements. The disadvantage here is that it is only possible with difficulty to operate these micromirror-based systems in such a way that the same optical path can be used for the transmission and reception paths. Also known is the use of microlenses to influence the direction of the beam.

WO 2018/111316 A1 describes an optical transmitting and receiving device constructed entirely using solid-state technology. The device has a multiplicity of optical input/output ports which can emit or receive light. By shifting an array of microlenses arranged over the ports relative to the ports, the direction of an incoming or outgoing light beam can be changed.

EP 3 000 157 B1 describes an optoelectronic device having an array of multiple VCSEL laser devices arranged on a substrate and multiple microlenses arranged over the VCSEL laser devices. The micro lenses focus and direct the light emitted by the VCSEL laser devices. By shifting the lenses away from a central axis of the respective laser components, the respective beam is deflected.

DE 10 2017 200 691 A1 describes a projection device and a method for scanning a solid angle area with a laser beam. In connection with a LIDAR system, laser pulses can be emitted and backscattered light can be received again. Micro-mirrors, which are excited to oscillate, are used to scan a solid angle range.

When using microlenses or micromirrors, a separate microlens or micromirror must be kept available and controlled for each light-emitting element and for each light-receiving element. The use of a single optical imaging system for all or a group of such elements would be desirable to reduce system complexity. Furthermore, with an imaging system that includes multiple optical elements, it is possible to better control the optical imaging properties.

Furthermore, when using the known microlens arrays, there is the problem of ensuring during the relative movement between the microlens and a light source or a detector that the light source or the detector remains in the focus of the respective microlens.

Disclosure of Invention

A scanning device for emitting light beams from a light source and/or for imaging light beams onto a detector is proposed. The scanning device comprises at least one optical imaging system, which is set up to image light incident on an object side onto an image shell, and at least one light source and/or at least one detector for detecting light imaged onto the detector. Provision is also made for the at least one light source and/or the at least one detector to be mounted on a movable platform of a parallel rocker, which is arranged and set up in such a way that the at least one light source and/or the at least one detector is positioned relative to the at least one optical imaging system to move that the at least one light source and/or the at least one detector moves along the image tray of the imaging system.

Within the scope of this application, to simplify the description, the terms of the beam lens optics and described the propagation of light from a light source via a bundle of light rays. As a rule, a divergent bundle of light rays emanates from a light source.

The at least one light source is preferably a LASER or a light-emitting diode. In this case, the light source is particularly preferably embodied as a laser diode, for example as an edge-emitting laser diode, or particularly preferably embodied as a VCSEL (vertical cavity surface emitting laser). With a VCSEL, the light emerges perpendicular to the plane of the semiconductor chip of the laser diode, which results in a particularly good beam quality. Light sources with wavelengths in the range from 1300 nm to 1600 nm and/or 840 nm to 1000 nm are preferably used.

The scanning device can exclusively comprise one or more detectors and accordingly in some embodiment variants have no light source. In other embodiments, the scanning device can include exactly one light source or a multiplicity of light sources.

The at least one detector is preferably a photodiode, which converts incident light into an electrical signal. Suitable photodiodes include, in particular, silicon PIN diodes, avalanche photodiodes (APD) and SPAD diodes (single photon avalanche diode).

The scanning device can exclusively comprise one or more light sources and accordingly in some embodiment variants have no detector. In other embodiments, the scanning device can include exactly one detector or a multiplicity of detectors.

If several light sources or detectors are arranged, then preferably in the range from 2 to 160 light sources and/or detectors are arranged, particularly preferably in the range from 2 to 16 light sources or detectors and very particularly preferably in the range from 2 to 4 light sources or detectors arranged.

The scanning device preferably comprises as many light sources as there are detectors, with one light source being assigned to one detector in each case.

If several light sources or detectors are used, it is preferable not to arrange them on a flat surface of the platform, but rather to arrange them following the curved spherical image shell. For this purpose, the platform can also have a spherical curvature or, starting from a flat surface of the platform, spacers with the curved spherical image shell of the following thickness can be used between the light source or the detector and the platform.

A light source or a detector is not only considered to be arranged in the spherical image shell if it is located exactly in the image shell and thus exactly in focus. The expression "moved along the spherical image shell of the imaging system" should also include small deviations from the optimal position, which result in particular from manufacturing and measurement tolerances, so that the at least one light source or the at least one detector is also slightly outside the spherical image shell can be located. The arrangement of a light source or a detector preferably deviates from the spherical image shell by less than the range of the depth of field defined by the imaging optics and the circle of confusion of the emitters or detectors. The circle of confusion is determined by the size of the radiating area or the size of the sensitive area of the detectors.

The imaging by the at least one optical imaging system preferably takes place on a spherical image shell with a radius of curvature R.

The at least one optical imaging system is preferably designed in such a way that telecentric imaging is realized on the image side facing the at least one light source or the at least one detector. In such an image-side telecentric imaging system, the exit pupil is at infinity. This means that when a bundle of light rays is imaged onto a detector, the beams are combined in a perpendicularly incident beam cone.

For light beams incident parallel to an optical axis of the imaging system, the at least one optical imaging system produces an image in a focus point that lies on the optical axis of the imaging system. Light rays incident at an angle to the optical axis are imaged, depending on their respective angle, onto a focus point which is shifted from the optical axis and lies on the spherical image shell of the imaging system.

In one embodiment variant, the scanning device can have precisely one optical imaging system. In other embodiment variants, the scanning device can include multiple optical imaging systems. For example, a first optical imaging system of the light source or be assigned to the light sources and a second optical imaging system can be assigned to the detector or detectors.

The scanning device preferably includes exactly one parallel rocker, even when using a plurality of optical imaging systems. However, it is also conceivable, for example, to arrange a parallel rocker for each optical imaging system.

The platform of the parallel rocker is arranged and set up in relation to the at least one optical imaging system in such a way that when the platform moves, the at least one detector and/or the at least one light source moves along the spherical image shell. Correspondingly, a detector is always located in a focal point onto which incident light rays are imaged at an angle corresponding to the position on the spherical image shell. Conversely, a light source is always located at a point on the image tray to emit a beam of parallel light rays through the imaging optical system at an angle corresponding to the light source's current position on the spherical image tray.

Accordingly, by adjusting the position of a light source on the spherical image tray, the direction in which light rays are emitted by the scanning device can be adjusted. Conversely, by adjusting the position of a detector on the spherical image tray, the direction from which light rays are imaged by the scanning device onto the detector and thus received can be adjusted accordingly.

By sequentially setting different positions of the at least one light source or the at least one detector on the spherical image shell, the proposed scanning device can be used to gradually scan an area surrounding the scanning device or a selected part thereof. Provision can be made to scan the position and thus the angle along one dimension, for example along a horizontal direction or a vertical direction, or along two dimensions, ie both along a horizontal direction and along a vertical direction perpendicular thereto.

The parallel rocker is preferably arranged in the scanning device in such a way that the at least one optical imaging system is stationary and the platform of the parallel rocker is moved relative to the rest of the scanning device. This is advantageous since the mass of the at least one optical imaging system is usually greater than the mass of the at least one light source and/or the at least one detector.

The parallel rocker is preferably fastened via movable mounts, each comprising a spacer element and two joint elements, with the length of the spacer elements corresponding to the radius of curvature R of the spherical picture shell. In each case, a spacer element is fastened to a base with a first joint element and fastened to the platform with a second joint element. 2 to 100 movable holders are preferably provided, particularly preferably 4 to 20 movable holders.

In principle, any joint known to a person skilled in the art can be used as joint elements. The joint elements are preferably designed as solid-state joints. A component or a region of a component is referred to as a flexure joint, which allows a relative movement, in particular a rotation, between two rigid body regions by bending. In this case, it can be provided, in particular, that an entire movable mount consisting of the two joint elements and the spacer element is manufactured in one piece, so that a movable mount is formed in one piece. It would also be conceivable to form the platform and the mounts of the parallel rocker as a one-piece component.

The flexure joints can be deflected by the action of force. When deflected from a basic position, the flexure joints have a restoring force in the direction of this basic position. This restoring force acts like a spring force, which always returns deflected flexure joints to the basic position after the force has been applied.

The platform of the parallel rocker is preferably designed in such a way that the movable mounts are arranged outside of the optical beam paths between the at least one optical imaging system and the at least one light source and/or the at least one detector.

The scanning device preferably has at least one actuator in order to drive a movement of the parallel rocker. Similar to known microelectromechanical systems (MEMS), the actuators can use capacitive or magnetic forces, for example. In the case of larger parallel swings, the actuator can also be designed as an electromechanical drive such as an electric motor with an eccentric.

The flexure joints are preferably designed as rotary joints, cardan joints, ball joints or combinations of these joints.

The holders, including the spacers and the joint elements, are preferably made of an electrically conductive material and are electrically connected to the at least one light source and/or the at least one detector. In this case, the electrically conductive mounts also serve as electrical leads, which simplifies the structure.

The parallel rocker is preferably set up for movements along two mutually orthogonal directions. In this case, the flexure joints are preferably designed as cardan joints and/or as ball joints. In this case, it is preferred to arrange at least two actuators in order to drive a movement along one of the two orthogonal (that is to say mutually perpendicular) directions.

In particular, the scanning device can be part of a LiDAR sensor, in which light beams are emitted within a field of view (FoV) and light reflected from objects is received again in the opposite direction. LiDAR systems measure the distance of an object, for example, by directly measuring the transit time (direct time of flight) of the emitted light pulse. A laser source emits a light pulse that is deflected onto an object by a suitable unit. The object reflects the light pulse, with the reflected light pulse being measured and evaluated by a detector. When using the transit time measurement, the system can determine the transit time based on the times of the emitted and received light pulse and the distance of the object to the transmitter/detector via the speed of light. Other methods are based on an indirect time of flight measurement (indirect time of flight) by modulating the light intensity or the light frequency itself.

One aspect of the invention is to provide a LiDAR sensor comprising one of the scanning devices described herein. In addition to at least one scanning device, the LiDAR sensor includes at least one light source and at least one detector as well as a first imaging system assigned to the at least one light source and a second imaging system assigned to the at least one detector. In this case, the at least one detector is set up to detect, for example, light from the at least one light source reflected on objects in the surrounding area when this is imaged on the detector.

The LiDAR sensor can include other components such as a housing and control electronics.

All light sources and all detectors of the LiDAR sensor are preferably arranged on a single parallel rocker. However, it is also conceivable to use a parallel rocker for the detectors and a parallel rocker for the light sources.

When used in a LiDAR sensor, the scanning device is used to sweep or scan a field of view with the light rays. During a scanning process, an angle at which an emitted light beam is deflected is changed continuously or in steps, so that the light beam gradually sweeps over or scans a predetermined field of view. Light reflected from objects is imaged in the opposite direction by the scanning device onto the detectors assigned to the light sources.

A plurality of light sources and a corresponding number of associated detectors are preferably arranged. Each of the light sources, when used in the LiDAR sensor, represents an independent channel for a measurement. Using multiple independent channels can reduce the time required for a complete scan of the field of view.

The scanning device for the LiDAR sensor preferably comprises a first array of light sources and a corresponding second array of detectors. The individual elements of an array, i.e. the individual light sources and detectors, can be arranged offset from one another in such a way that the distances (also called “pixel pitch”) are smaller than the distances along one dimension, i.e. viewed along a horizontal or vertical direction, for example Elements themselves. Thus, either a particularly small line spacing or a particularly small row spacing is possible in the array arrangement.

In one embodiment variant, the arrays are line arrays or a plurality of line arrays that are laterally offset from one another. In this case, a plurality of light sources or detectors are arranged along a main axis predetermined by the alignment of the line array. In this embodiment variant, the scanning device is preferably designed as a 1D scanning device, with the scanning device moving along a direction that is perpendicular to the course of the main axis of the array or arrays. For example, the orientation of the major axis of the array(s) may be vertical and the scanning device may be configured to perform a scan in a horizontal direction perpendicular thereto.

In another embodiment, a two-dimensional array of light sources or detectors is used, so that they have a rectangular arrangement. For example, a 2x4 arrangement with four columns in two rows in connection with a 2D scanning device covers an area four times as large in the horizontal direction and twice as large in the vertical direction as the field-of-view with the same range of motion. Conversely, if the field-of-view remains the same, this can already be covered with a smaller range of movement of the scanning device.

The two optical imaging systems of the scanning device of the LiDAR sensor are preferably designed in such a way that telecentric imaging is realized on the image side facing the at least light source or the at least one detector.

The two optical imaging systems of a scanning device set up for use in the LiDAR sensor preferably each comprise two or more lenses, imaging systems with exactly two lenses being particularly preferred.

The optical imaging systems are preferably designed in such a way that they each have a spherical image shell whose radii of curvature match.

The optical system, which is formed from the two lenses, is preferably calculated in such a way that the image-side telecentric imaging is realized.

In this case, an object-side first lens preferably has a planar surface on an outside. This flat surface preferably also forms a closing surface of the LiDAR sensor to the outside, so that additional windows or transparent cover panes can be omitted.

The first lens is preferably made of mineral glass, which is resistant to environmental influences such as moisture, dust and dirt and is suitable for mechanical cleaning, for example with a wiper system. Preferably, the LiDAR sensor includes such a wiper system in combination with a planar exterior of the first lens to remove moisture such as water droplets and dirt from the exterior surface of the first lens.

The second lens can also be made of mineral glass. However, since the second lens is protected from environmental influences, it can also be made of other materials, such as organic glass or an optical plastic. This makes it possible to easily manufacture even complex surfaces on the second lens, for example by means of injection molding. However, the material used for the second lens should preferably be suitable for automotive use, ie suitable for the temperature ranges occurring when used in an automobile, in particular for a temperature range from -40°C to +125°C.

The LiDAR sensor and/or the scanning device can also include other optical elements in addition to the optical imaging system. For example, one or more optical filters can be provided in order to block out specific parts of the light spectrum or only allow specific parts of the light spectrum to pass. The at least one optical filter is preferably matched to the properties of the at least one light source, so that light from the at least one light source can be emitted unhindered and vice versa can be imaged again unhindered onto the at least one detector. Other areas of the light spectrum are preferentially suppressed by the optical filter.

Another aspect of the invention is the provision of a method for operating one of the scanning devices described herein or for operating one of the LiDAR sensors described herein, the parallel rocker due to its mass and a restoring force of the movable mounts for a swinging movement of the platform along the image shell of the imaging system has a resonant frequency. It is provided that a movement of the platform is stimulated in order to move a light beam from a light source and/or to image light beams from different directions from the environment onto a detector. The movement is preferably an oscillating movement. This oscillating movement is preferably excited with a frequency that corresponds to the resonant frequency. The oscillating movement can in particular be a quasi-static oscillation, a 2D oscillation or a triangular oscillation.

By appropriately selecting the number and the restoring force of the movable mounts and the mass of the platform of the parallel rocker, the resonant frequency can be selected according to the requirements of the scanning device or the LiDAR sensor.

For a corresponding excitation of a movement, for example, an actuator can be controlled with a corresponding signal. The signal can, for example, have a sinusoidal oscillation or a sawtooth oscillation as the oscillation form. An excitation can take place linearly when implemented as a 1D scanning device and correspondingly two-dimensionally when implemented as a 2D scanning device using, for example, two actuators. The excitation can be stationary, quasi-stationary or resonant, for example. A quasi-steady-state excitation means that although a periodic basic movement is carried out by the parallel rocker, the movement is greatly accelerated or decelerated within the period. This creates movement patterns that clearly deviate from a harmonic oscillation. Of practical importance are triangular movements or a "dwelling" in one position, for example to approach a single object in the environment when used in a sensor.

Advantages of the Invention

In the proposed scanning device, by arranging a light source and/or a detector on a parallel rocker, the light source or the detector can be moved along a curved path by simply deflecting the parallel rocker, which corresponds to the image shell of an imaging system. Thus, when the light source or the detector moves essentially laterally with respect to an optical axis of the imaging system, these always remain in the focus of the optical imaging system. Advantageously, such a parallel rocker is easy to manufacture and can also be used to arrange a plurality of light sources or detectors.

Advantageously, both a light source and a detector of a LiDAR sensor assigned to the light source can be arranged on the same parallel rocker arm, so that there is a fixed mechanical coupling of the transmission path and the reception path of the LiDAR sensor. Thus, such a LiDAR sensor always looks exactly in the direction in which a light beam is emitted.

Since a large number of detectors and light sources can also be arranged on the same parallel rocker, such a LiDAR system comprising such a scanning device can also easily be expanded by many channels in order to speed up the scanning of the surroundings.

The imaging system of the proposed scanning device can have a flat surface as the outer surface of the object-side lens. Advantageously, this can simultaneously serve as a cover plate for the scanning device or a LiDAR sensor comprising the scanning device and can also be easily cleaned of dirt and water droplets, for example with a wiping device. It is no longer necessary to arrange additional cover panes or protective panes, which means that the construction of the LiDAR sensor can be simplified.

Another significant advantage is that, due to the detection on a spherical image shell, the imaging optics or the imaging system manages with few lenses despite the large field of view and can therefore be implemented more easily and cost-effectively.

character list

Embodiments of the invention are explained in more detail with reference to the drawings and the following description.

• 1 eine schematische Schnittansicht einer Scanvorrichtung von der Seite,
• 2a und 2b zwei Ausführungsbeispiele für eine Parallelschwinge,
• 3a ein als Drehgelenk ausgebildetes Festkörpergelenk.
• 3b ein als Kardangelenk ausgebildetes Festkörpergelenk,
• 3c ein als Kugelgelenk ausgebildetes Festkörpergelenk,
• 4a, 4b und 4c drei Ausführungsbeispiele für Anordnungen von Lichtquellen und Detektoren, und
• 5 eine schematische Schnittansicht eines LiDAR-Sensors von der Seite.

Show it:

• 1 a schematic sectional view of a scanning device from the side,
• 2a and 2 B two design examples for a parallel rocker,
• 3a a flexure joint designed as a rotary joint.
• 3b a flexure joint designed as a cardan joint,
• 3c a flexure joint designed as a ball joint,
• 4a , 4b and 4c three exemplary arrangements of light sources and detectors, and
• 5 a schematic sectional view of a LiDAR sensor from the side.

Embodiments of the invention

In the following description of the embodiments of the invention, the same or similar elements are denoted by the same reference symbols, with a repeated description of these elements being dispensed with in individual cases. The figures represent the subject matter of the invention only schematically.

1 shows a scanning device 10 in a schematic sectional view from the side.

The scanning device 10 includes an optical imaging system 20 with exactly two lenses 22, 24 in the exemplary embodiment shown. A first lens 22 is arranged on the object side and has a first planar surface on an outwardly facing side. An inwardly facing second surface of the first lens 22 is convexly curved. A second lens 24, which is arranged on the image side, has two convex surfaces in the exemplary embodiment shown. The two lenses 22 , 24 are accommodated in a holder 26 . An optical axis 28 of the optical imaging system 20 is drawn in with a dashed line.

The bracket 26 is connected to a base 42 which carries a parallel rocker 40 . The parallel rocker 40 has a platform 44 which is connected to the base 42 via movable mounts 50 . In the sectional view of 1 two of the movable mounts 50 are visible. The movable mounts 50 are arranged in such a way that they do not impede the optical path between the imaging system 20 and the side of the platform 44 facing the imaging system 20 .

The movable mounts 50 each have a first joint member 52, a spacer member 56 and a second joint member 54. The first joint element 52 is in each case connected to the base 42 and the second joint element 54 is in each case connected to the platform 44 . The spacer element 56 is arranged between a first joint element 52 and a second joint element 54 in each case. The length of the spacer 56 corresponds to a radius of curvature R of a spherical image shell 30 of the optical imaging system 20. The spherical image shell 30 is the curved surface that contains the focus points onto which parallel incident beams of rays are imaged by the optical imaging system 20.

On the side of the platform 44 of the parallel rocker 40 that faces the optical imaging system 20, in 1 illustrated embodiment, a light source 60, arranged, which is designed for example as a laser diode. Due to this arrangement, the light source 60 is always in focus or on the spherical image shell 30 of the imaging system 20, even if the platform 44 of the parallel rocker 40 is deflected. By shifting the light source 60 on the image tray 30, the direction in which a parallel bundle of rays is emitted by the scanning device 10 is changed.

If instead of or in addition to the light source 60 a detector 70 compare 5 , placed on the platform 44, the direction from which the incident bundles of parallel light rays are imaged onto the detector 70 by the optical imaging system 20 is changed by deflecting the platform 44 accordingly.

By appropriately moving the platform 44 relative to the optical imaging system 20, the surroundings of the scanning device 10 or a selected part thereof can be systematically scanned by an emitted light beam gradually sweeping over a predetermined field of view of the surroundings.

2a shows a first example of a parallel rocker 40 with a platform 44 which is connected to a base 42 via movable mounts 50 . In the first example, the joint elements 52, 54 are designed as rotary joints, which are composed of several components.

2 B 12 shows a second example of a parallel rocker 40 with a platform 44 which is connected to a base 42 via movable mounts 50. FIG. In the second example, the joint elements 52, 54 are designed as solid joints, which are each designed as a thinned area of the movable mounts 50. Due to the low material thickness of the movable mounts 50 in the areas of the joint elements 52, 54, elastic deformation is possible and plastic deformations and fatigue fractures are avoided.

3a shows a flexure joint designed as a rotary joint. This only allows tilting along one direction.

3b shows a flexure joint designed as a cardan joint. This allows tilting along two mutually orthogonal directions.

3c shows a flexure joint designed as a ball joint. In addition to tilting along two mutually orthogonal directions, rotation is also possible here.

the 4a , 4b and 4c show three exemplary embodiments for arrangements of light sources 60 and detectors 70 on the platform 44 of a parallel rocker 40. In all three exemplary embodiments, the platform 44 or the corresponding parallel rocker 40 is there, see FIG 1 , designed to move along one dimension. The detectors 70 and light sources 60 are arranged as a line array to enable two-dimensional scanning. The arrangements each have a first array 62 for the light sources 60 and a second array 72 for the detectors 70 .

In the first example the 4a the first array 62 and the second array 72 each comprise four elements, which are arranged one below the other in a column. When scanning by moving the platform 44 along the horizon perpendicular thereto In the vertical direction, four lines can be scanned.

In the second example the 4b the first array 62 and the second array 72 each comprise seven elements which are arranged in two columns one below the other. Four elements are arranged in each column and three elements are arranged in each other column. The two columns are arranged laterally offset from one another, so that a distance between two elements in each case is reduced in the vertical direction perpendicular to the scanning direction. Thus, when scanning by moving the platform 44, a seven-line scan can be performed.

In the third example the 4b the first array 62 and the second array 72 each comprise twelve elements, which are arranged in three columns of four elements each. The columns are each arranged laterally offset from one another, so that a distance between two elements in each case is reduced in the vertical direction perpendicular to the scanning direction. Thus, when scanning by moving the platform 44, a twelve-line scan can be performed.

5 shows a LiDAR sensor 100 in a schematic sectional view from the side. The LiDAR sensor 100 includes a scanning device 10 which, in the embodiment variant shown, has a first optical imaging system 20' and a second optical imaging system 20'' with associated spherical image shells 30', 30''. The optical imaging systems 20', 20'' each have a first lens 22 and a second lens 24. To simplify the illustration, no holder 26 is shown, compare 1 .

The LiDAR sensor 100 includes a parallel rocker 40 with a platform 44 on which light sources 60 and detectors 70 are arranged. The light sources 60 are assigned to the first optical imaging system 20' and the detectors 70 are assigned to the second optical imaging system 20". To simplify the illustration, only two light sources 60 and two detectors 70 are in each case 5 shown.

In the 5 five light beam bundles 111, 112, 113, 114, 115 are shown for each of the two optical imaging systems to clarify the functional principle. Each light beam bundle 111, 112, 113, 114, 115 has a plurality of light beams running parallel on the object side of the respective optical imaging system 20', 20''. The individual light beams of the light beam bundles 111, 112, 113, 114, 115 each run on the image side in a focal point on the spherical image shells 30', 30" together.

As the representation of 5 can be removed, the detectors 70 and the light sources 60 are each arranged on the platform 44 in such a way that they lie on the corresponding spherical image shell 30', 30" when the platform is not deflected. This means that the light-emitting Part of a light source 60 or the light-receiving part of a detector 70 on the respective spherical image shell 30, 30 "lies. The length of the spacers 56 of the movable mounts 50 of the parallel rocker 40 is selected to be identical to a radius of curvature R of the spherical image shells 30', 30". This ensures that when the platform 44 is deflected, the light sources 60 or the detectors 70 move along the respective spherical image shell 30', 30" move. The light sources 60 and the detectors 70 are therefore always in the focus of the respective optical imaging system 20', 20".

The direction in which a light beam 111, 112, 113, 114, 115 is emitted or from which light beams 111, 112, 113, 114, 115 are imaged onto a detector 70.

The invention is not limited to the exemplary embodiments described here and the aspects highlighted therein. Rather, within the range specified by the claims, a large number of modifications are possible, which are within the scope of expert action.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• WO 2018/111316 A1 [0004]
• EP 3000157 B1 [0005]
• DE 102017200691 A1 [0006]

Claims (10)

Scanning device (10) for emitting light beams from a light source (60) and/or for imaging light beams onto a detector (70), comprising at least one optical imaging system (20) which is set up to project light incident on an object side onto an image shell (30) image, and at least one light source (60) and/or at least one detector (70) for detecting light imaged on the detector (70), characterized in that the at least one light source (60) and/or the at least one detector (70 ) are mounted on a movable platform (44) of a parallel rocker (40), which is arranged and set up in such a way that the at least one light source (60) and/or the at least one detector (70) is positioned relative to the at least one optical imaging system (20) to move that the at least one light source (60) and/or the at least one detector (70) moves along the image tray (30) of the imaging system (20). Scanning device (10) after claim 1 , characterized in that the parallel rocker (40) is fastened via movable mounts (50), each comprising a spacer element (56) and two joint elements (52, 54), the length of the spacer elements (56) corresponding to the radius of curvature R of a spherical picture shell (30 ) and each spacer member (56) is secured to a base (42) by a first hinge member (52) and to the platform (44) by a second hinge member (54). Scanning device (10) after claim 2 , characterized in that the joint elements (52, 54) are designed as solid joints. Scanning device (10) after claim 3 , characterized in that the solid joints are designed as rotary joints, cardan joints, ball joints or combinations of these joints. Scanning device (10) according to one of claims 2 until 4 , characterized in that the spacers (56) and the joint elements (52, 54) are made of an electrically conductive material and are electrically connected to the at least one light source (60) and/or the at least one detector (70). Scanning device (10) according to one of Claims 1 until 5 , characterized in that the parallel rocker (40) is set up for movements along two mutually orthogonal directions. LiDAR sensor (100) comprising a scanning device (10) according to one of Claims 1 until 6 , characterized in that the scanning device (10) has at least one light source (60) and at least one detector (70) as well as a first imaging system (20') assigned to the at least one light source (60) and a second imaging system (20') assigned to the at least one detector (70 ) associated imaging system (20"), wherein the at least one detector (70) is set up to detect reflected light of the at least one light source (60). LiDAR sensor (100) after claim 7 , characterized in that the scanning device (10) comprises a first array (62) of light sources (60) and a corresponding second array (72) of detectors (70). LiDAR sensor (100) after claim 7 or 8th , characterized in that the optical imaging systems (20', 20") each comprise two or more lenses (22, 24), an object-side first lens (22) having a flat surface on an outside. Method for operating a scanning device (10) according to one of Claims 1 until 6 or for operating a LiDAR sensor (100) according to one of Claims 7 until 9 , wherein the parallel rocker (40) has a resonant frequency due to its mass and a restoring force of the movable mounts (50) for an oscillating movement of the platform (44) along the image shell (30) of the imaging system (20), characterized in that a movement of the platform (44) is excited in order to move a light beam from a light source (60) and/or to image light beams from different directions from the environment onto a detector (70).

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