WO2018029136A1

WO2018029136A1 - Lidar system having a movable optical fibre

Info

Publication number: WO2018029136A1
Application number: PCT/EP2017/069909
Authority: WO
Inventors: Florian Petit
Original assignee: Blickfeld GmbH
Priority date: 2016-08-08
Filing date: 2017-08-07
Publication date: 2018-02-15
Also published as: DE102016009936A1

Abstract

An arrangement comprises an optical fibre (201) having a first end (205) and a second end. The arrangement (100) comprises a fastening (250) that fastens the optical fibre (201) to a fastening point (206). Light (191, 192) can be fed into the second end of the optical fibre (201). An actuator is configured to move the first end (205) of the optical fibre (201) relative to the fastening point (206). In some examples, a LIDAR system is configured to carry out a scanned distance measurement of objects in the surroundings of the arrangement, on the basis of the light (191, 192).

Description

LIDAR SYSTEM WITH MOVABLE LIGHT FIBER

TECHNICAL FIELD Various embodiments relate to an assembly comprising an optical fiber and an actuator configured to move a first end of the optical fiber opposite a fixing location of the optical fiber. In various embodiments, the arrangement also comprises a LIDAR system, which is set up to perform a scanned distance measurement of objects in the vicinity of the arrangement based on laser light.

BACKGROUND

The distance measurement of objects is desirable in various fields of technology. For example, in the context of autonomous driving applications, it may be desirable to detect objects around vehicles and, in particular, to determine a distance to the objects.

One technique for measuring the distance of objects is the so-called LIDAR technology (light detection and ranging, sometimes also LADAR). In this case, pulsed laser light is emitted by an emitter. The objects in the environment reflect the laser light. These reflections can then be measured. By determining the transit time of the laser light, a distance to the objects can be determined.

In order to detect the objects in the environment spatially resolved, it may be possible to scan the laser light. Depending on the beam angle of the laser light different objects in the environment can be detected.

However, conventional spatially resolved LIDAR systems have the disadvantage that they can be comparatively expensive, heavy, maintenance-intensive and / or large. Typically, LIDAR systems use a scanning mirror that can be placed in different positions. An accuracy with which the position of the scanning mirror can be determined thereby typically limits the accuracy of the spatial resolution of the LIDAR measurement. In addition, the scanning mirror is often large and the adjustment mechanism can be maintenance-intensive and / or expensive.

From Leach, Jeffrey H., Stephen R. Chinn, and Lew Goldberg. "Monostatic all-fiber scanning LADAR system." Applied optics 54.33 (2015): 9752-9757 are techniques known to agents an adjustable curvature of an optical fiber to perform a scanned LIDAR measurement. Corresponding techniques are also from Mokhtar, MHH, and RRA Syms. "Tailored fiber waveguides for precise two-axis Lissajous scanning." Optics express 23.16 (2015): 20804-2081 1 known.

Such techniques have the disadvantage that the curvature of the optical fiber is comparatively limited. In addition, it may be difficult to implement optics that avoid beam divergence of laser light exiting the end of the optical fiber. SUMMARY

Therefore, there is a need for improved techniques for measuring the distance of objects around an array. In particular, there is a need for such techniques which overcome at least some of the above limitations and disadvantages.

This object is solved by the features of the independent claims. The features of the dependent claims define embodiments.

In one example, an arrangement includes an optical fiber having a first end and a second end. The assembly also includes a fixture which fixes the optical fiber at a location of fixation between the first end and the second end. The arrangement also includes a terminal configured to supply light to the second end of the optical fiber. The arrangement also includes at least one actuator. The at least one actuator is arranged to move the optical fiber in the area between the fixing point and the first end. The rotation takes place between a first twist and a second twist. The arrangement also includes a LIDAR system. The LIDAR system is set up to perform a scanned distance measurement of objects in the vicinity of the arrangement based on the light. In another example, an arrangement includes an optical fiber having a first end and a second end. The assembly also includes a fixture which fixes the optical fiber at a location of fixation between the first end and the second end. The arrangement also includes a terminal configured to supply light to the second end of the optical fiber. The assembly also includes at least one actuator configured to move the optical fiber in the region between the fixation site and the first end. The assembly also includes a lens fixedly connected to the first end of the optical fiber. The arrangement also includes a LIDAR system which is arranged to based on the light to perform a scanned distance measurement of objects in the vicinity of the arrangement.

In one example, an arrangement includes an optical fiber having a first end and a second end. The assembly also includes a fixture which fixes the optical fiber at a location of fixation between the first end and the second end. The arrangement also includes a terminal configured to supply light to the second end of the optical fiber. The arrangement also includes at least one actuator. The at least one actuator is arranged to move the optical fiber in the area between the fixing point and the first end. The movement takes place between a first torsion and a second torsion. For example, the device could be an RGB projector - e.g. attached to a pair of data glasses - or implement an endoscope.

In another example, a method includes injecting light into a second end of an optical fiber. The method further comprises fixing the optical fiber between a first end of the optical fiber and the second end of the optical fiber, at a fixing point of the optical fiber. The method also includes moving the optical fiber in the region between the fuser and the first end between a first twist and a second twist. Optionally, the method also includes performing a scanned LIDAR distance measurement of objects around the device based on the light or RGB projection or endoscopy.

In one example, an arrangement includes an optical fiber having a first end and a second end. The assembly also includes a fixture which fixes the optical fiber at a location of fixation between the first end and the second end. The arrangement also includes a terminal configured to supply light to the second end of the optical fiber. The assembly also includes an actuator configured to move the first end of the optical fiber opposite the fixation location between a first position and a second position. Optionally, the assembly also includes a LIDAR system configured to perform a scanned distance measurement of objects around the assembly based on the light.

In another example, a method includes injecting light into a second end of an optical fiber. The method further comprises fixing the optical fiber between a first end of the optical fiber and the second end of the optical fiber, at a fixing point of the optical fiber. The method also includes moving the first end of the optical fiber opposite the locator between a first position and a second position. The Optionally, the method also includes performing a scanned LIDAR distance measurement of objects in the vicinity of the array based on the light.

The features and features set out above, which are described below, can be used not only in the corresponding combinations explicitly set out, but also in other combinations or isolated, without departing from the scope of the present invention.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A schematically illustrates an arrangement configured to perform a scanned distance measurement of objects in the vicinity of the arrangement according to various embodiments, the arrangement comprising an emitter for laser light, a detector for laser light and a LIDAR system.

FIG. 1B schematically illustrates the arrangement of FIG. 1A in more detail, the arrangement including a scanning device configured to scan the laser light. FIG. FIG. 2 schematically illustrates a scanning device having an optical fiber with a movable end according to various embodiments. FIG.

FIG. FIG. 3A schematically illustrates a scan device with a light fiber having a movable end according to various embodiments, wherein FIG. 3A illustrates a curvature of the optical fiber.

FIG. FIG. 3B schematically illustrates a scan device with a light fiber having a movable end according to various embodiments, wherein FIG. 3B illustrates a twist of the optical fiber.

FIG. 4A schematically illustrates a scanning device having an optical fiber having a movable end and a lens according to various embodiments.

FIG. 4B schematically illustrates the focal length of the lens of FIG. 4A according to various embodiments. FIG. 4C schematically illustrates a scanning device having an optical fiber with a movable end and a lens fixedly connected to the movable end and a deflection unit fixedly connected to the movable end according to various embodiments.

FIG. 5 schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises a fiber Bragg grating. FIG. 6A schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises two fiber Bragg gratings.

FIG. 6B schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises two fiber Bragg gratings.

FIG. 6C schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises four fiber Bragg gratings.

FIG. 7 schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises four fiber Bragg gratings.

FIG. 8A schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises four fiber Bragg gratings. FIG. 8B schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, the positioning device comprising a beam splitter and a position sensitive detector (PSD). FIG. 8C schematically illustrates a positioning device for determining a position of the movable end of the optical fiber according to various embodiments, wherein the positioning device comprises a beam splitter and a PSD. FIG. 9 schematically illustrates an actuator for moving the movable end of the optical fiber according to various embodiments. FIG. 10A schematically illustrates an actuator for moving the movable end of the optical fiber according to various embodiments.

FIG. 10B schematically illustrates an actuator for moving the movable end of the optical fiber according to various embodiments.

FIG. 10C schematically illustrates an actuator for moving the movable end of the optical fiber according to various embodiments.

FIG. 1 1 schematically illustrates an actuator for moving the movable end of the optical fiber according to various embodiments.

FIG. 12A schematically illustrates an arrangement configured to perform a scanned distance measurement of objects in the vicinity of the assembly according to various embodiments.

FIG. 12B schematically illustrates an arrangement configured to perform a scanned distance measurement of objects in the vicinity of the assembly according to various embodiments. FIG. 12C schematically illustrates an arrangement configured to perform a scanned distance measurement of objects in the vicinity of the assembly according to various embodiments.

FIG. 13 schematically illustrates an arrangement configured to perform a scanned distance measurement of objects in the vicinity of the assembly according to various embodiments.

FIG. 14 schematically illustrates an arrangement configured to perform a scanned distance measurement of objects in the vicinity of the assembly according to various embodiments.

FIG. 15 is a flowchart of a method according to various embodiments. FIG. 16 schematically illustrates a first-order curvature mode and a second-order curvature mode according to various embodiments. FIG. 17 schematically illustrates an arrangement according to various embodiments.

FIG. 18 schematically illustrates a two-dimensional scan area of the arrangement of FIG. 17th

DETAILED DESCRIPTION OF EMBODIMENTS

The above-described characteristics, features, and advantages of this invention, as well as the manner in which they will be achieved, will become clearer and more clearly understood in connection with the following description of the embodiments, which will be described in detail in conjunction with the drawings.

Hereinafter, the present invention will be described with reference to preferred embodiments with reference to the drawings. In the figures, like reference characters designate the same or similar elements. The figures are schematic representations of various embodiments of the invention. Elements shown in the figures are not necessarily drawn to scale. Rather, the various elements shown in the figures are reproduced in such a way that their function and general purpose will be understood by those skilled in the art. Connections and couplings between functional units and elements illustrated in the figures may also be implemented as an indirect connection or coupling. Functional units can be implemented as hardware, software or a combination of hardware and software. Hereinafter, various techniques for scanning light will be described. For example, the following techniques may enable two-dimensional scanning of light or one-dimensional scanning of light. Scanning may refer to repeated emission of the light at different angles of radiation. The scanning may indicate the repeated scanning of different points in the environment by means of the light. For example, the amount of different points in the environment and / or the amount of different radiation angles may define a scan area. In various examples, it is possible to scan laser light. In this case, for example, coherent or incoherent laser light can be used. It would be possible to use polarized or unpolarized laser light. For example, it would be possible for the laser light to be pulsed. For example, short laser pulses with pulse widths in the range of femtoseconds or picoseconds or nanoseconds can be used. The laser light may have a wavelength in the range of 700-1800 nm. For the sake of simplicity, reference will now be made primarily to laser light; however, the various examples described herein may also be used to scan light from other light sources, for example broadband light sources or RGB light sources. RGB light sources herein generally refer to light sources in the visible spectrum, the color space being covered by superimposing several different colors, such as red, green, blue or cyan, magenta, yellow, black.

In various examples, a movable end of an optical fiber is used to scan the laser light. Sometimes, optical fibers are also referred to as optical fibers or glass fibers. However, it is not necessary that the optical fibers are made of glass. The optical fibers may be made of plastic, glass or other material, for example. Typically, the optical fibers have a core in which the injected laser light is propagated and enclosed by total reflection at the edges. In various examples, so-called single mode fibers or multimode fibers may be used. The various optical fibers described herein may, for example, have a circular cross-section. For example, it would be possible for the various optical fibers described herein to have a diameter not smaller than 50μηη, optionally not <150μηη, further optional not <500μηη, further optional not <1mm. For example, the various optical fibers described herein may be made bendable. For this, the material of the optical fibers described herein may have some elasticity. For example, the movable end of the fiber could be moved in one dimension or in two dimensions. For example, it would be possible for the movable end of the fiber to be tilted with respect to a fixing point of the optical fiber; this results in a curvature of the optical fiber. Alternatively or additionally, it is possible that the movable end of the fiber is twisted along the fiber axis (torsion). By moving the movable end of the optical fiber can be achieved that the fed into the optical fiber laser light is emitted at different angles. This can be a Environment with the laser light to be scanned. Depending on the amount of movement of the movable end, scan areas of different sizes can be implemented.

In each of the various examples described herein, it is possible to implement a twist of the movable end of the optical fiber, alternatively or in addition to a curvature of the movable end of the optical fiber.

In general, such techniques can be used to scan light in a wide variety of applications. Examples include endoscopes and RGB projectors and printers. In various examples, LIDAR techniques can be used. The LIDAR techniques can be used to perform a spatially resolved distance measurement of objects in the environment. For example, the LIDAR technique may include transit time measurements of the laser light between the moveable end of the fiber, the object, and a detector.

Although various examples are described in terms of LIDAR techniques, the present application is not limited to LIDAR techniques. For example, the aspects described herein with respect to the scanning of the laser light by means of the movable end of the optical fiber can also be used for other applications. Examples include, for example, projecting image data in a projector - e.g. an RGB light source can be used.

Various examples are based on the finding that it may be desirable to carry out the scanning of the laser light with a high accuracy with respect to the emission angle. For example, in the context of LIDAR techniques, spatial resolution of the distance measurement may be limited by inaccuracy of the emission angle. Typically, a higher (lower) spatial resolution is achieved the more accurate (less accurate) the radiation angle of the laser light can be determined. In this case, it is not necessary in various examples for certain emission angles or positions of the movable end of the fiber to be reproducibly converted in different scan positions. It is not necessary to interrupt the scanning process at certain positions of the movable end of the fiber: a continuous step-and-shoot technique may be used instead of a step-and-shoot technique. By an accurate measurement of the position of the movable end of the fiber, a LIDAR measurement can instead be implemented at any radiation angles and by the corresponding Information about the beam angle, for example, be interpolated to a fixed angle grid.

Various examples relate to a positioning device arranged to output a signal indicative of the angle of radiation. This means that the positioning device could be arranged to output a signal indicative of the position of the movable end of the optical fiber. For example, it would be possible for applications that rely on scanning the laser light to use the signal from the positioning device to achieve greater accuracy. By the positioning device, it is unnecessary to repeatedly implement certain positions of the end of the fiber: rather, the actual position of the movable end of the fiber or the actual radiation angle can be measured. This reduces the complexity of driving the actuator to position the movable end of the fiber: the actuator may e.g. be arranged to continuously reciprocate the movable end between two extreme positions - for example, in contrast to so-called step-and-shoot approaches, where the scanning process is interrupted for the measurement in an intermediate position. The actuator need not be set up to implement certain positions between the extreme positions. The actuator may e.g. be arranged to reciprocate the movable end of the fiber between two extreme positions at a substantially constant speed. In particular, the actuator may be configured such that when moving the movable fiber between two extreme positions there is no decrease in the speed to zero at intermediate positions.

In some examples, the positioning device may be configured to perform an optical measurement. For example, the positioning device could be configured to optically measure the curvature and / or torsion of the optical fiber. Alternatively or additionally, the positioning device could be designed to optically measure the emission angle of the laser light, for example based on the laser light itself. Such an optical measurement of the position can be particularly particularly accurate. In addition, high sampling frequencies may be possible. This promotes continuous step-and-shoot scanning techniques.

In some examples, the positioning device may be configured to determine the position of the movable end of the optical fiber by a state measurement of the light exiting the optical fiber. In contrast to other indirect techniques - which take into account, for example, a state measurement of the actuator - such a particularly accurate determination of the angle at which the laser light is emitted to take place. In addition, a particularly rapid determination of the angle at which the laser light is emitted, take place. The sampling frequency at which the positioning device outputs the signal can be particularly high. In some examples, the positioning device may be configured to determine the position of the movable end of the optical fiber by a state measurement of the optical fiber itself. In contrast to other indirect techniques - which take into account, for example, a state measurement of the actuator - such a particularly accurate determination of the angle at which the laser light is emitted to take place. In addition, a particularly rapid determination of the angle at which the laser light is emitted, take place. The sampling frequency at which the positioning device outputs the signal can be particularly high.

In various examples, the positioning device comprises a PSD. The PSD may e.g. operated based on the lateral photoelectric effect. For this purpose, for example, a PIN diode can be used. Alternatively or additionally, a discrete PSD could also be used. This could for example comprise a plurality of discrete pixels, for example in the form of a CCD sensor or a CMOS sensor. By means of the PSD it may be possible to determine the current angle at which the laser light is emitted. In some examples, a translucent PSD (PSD) may be used to prevent damage.

In various examples, the positioning device comprises at least one fiber Bragg grating. The fiber Bragg grating may correspond to a periodic modulation of the refractive index of a core of an optical fiber. The fiber Bragg grating may have a length in the range of 100 μηι - 1 mm. A periodicity of the fiber Bragg grating may be in the range of the wavelength of light. When light is incident on the fiber Bragg grating whose wavelength satisfies the Bragg relationship, then a significant portion of the incident light may be reflected. By measuring the amplitude of the reflected light, a change in length of the optical fiber in the region of the fiber Bragg grating can be deduced. For example, the change in length of the optical fiber in the region of the fiber Bragg grating may be caused by a curvature of the optical fiber due to the movement of the free end of the optical fiber. For the evaluation of the reflected light, for example, a spectrometer can be used. However, it would also be possible for the evaluation of the reflected light to use an edge filter which has a bandpass in the region of an edge of the filter curve of the fiber Bragg grating. Thus, different intensities behind the edge filter can be indicative of a change in reflection be on the fiber Bragg grating. Corresponding techniques are disclosed in DE 10 2009 014 478 B4, the relevant disclosure content being incorporated herein by reference. For example, the actuator may be configured to implement a resonant drive. This means that the actuator can be set up to resonantly excite the mass of the end of the optical fiber and other elements in this area, such as further optical fibers and / or lenses, etc. In principle, an eigenmode of first order and / or one or more eigenmodes of higher order can be resonantly excited: This applies to the curvature and / or the torsion of the optical fiber. It would also be possible for the actuator to implement a non-resonant drive.

Various effects can be achieved by the techniques described herein. For example, it may be possible to implement an arrangement that implements the scanning of laser light in a particularly simple, robust and with a small installation space. In particular, compared to reference implementations that use a scanning mirror, the movement of the free end of the optical fiber can be implemented with simple components and very highly integrated. In addition, a wear of a corresponding arrangement in the course of operation may be less strong, as for scanning mirror.

By using a positioning device - in particular with a PSD and / or a fiber Bragg grating - a particularly accurate positioning of the movable end of the optical fiber can be performed. This may in turn make it possible to ensure a high spatial resolution for applications such as the LIDAR technique, which rely on scanning the laser light over the environment. The high spatial resolution can also be achieved for continuous step-and-shoot approaches.

FIG. 1A illustrates aspects relating to a scanned distance measurement of objects 195, 196. In particular, FIG. 1A Aspects related to a distance measurement based on the LIDAR technique.

In FIG. 1A, an arrangement 100 is shown that includes an emitter 101 for laser light 191, 192. For example, the emitter 101 could be a laser light source and / or an end of an optical fiber that emits laser light. In this case, for example, the laser light could be fed via a connection or an optical coupler into the further end of the optical fiber. The laser light is emitted, for example pulsed (primary radiation). The transit time of a laser light pulse between the emitter 101, an object 195, 196 and a Detector 102 may be used to determine a distance between array 100 and objects 195, 196. For example, a photodiode coupled to a wavelength filter that selectively passes light at the wavelengths of the laser light 191, 192 may be used as the detector 102. As a result, the laser light 191, 192 (secondary radiation) reflected by the objects 195, 196 can be detected. In principle, it is possible that the emitter 101 and the detector 102 are implemented as separate components; However, it would also be possible for the reflected laser light 191, 192 to be detected via the same optics that the emitter 101 is also implemented. The detector 102 may include, for example, an avalanche photodiode. The detector 102 can be operated, for example, by means of photon correlation. For example, the detector 102 may be configured to detect individual photons.

A LIDAR system 103 is provided that is coupled to the emitter 101 and the detector 102. For example, the LIDAR system may be configured to achieve time synchronization between the emitter 101 and the detector 102. The LIDAR system 103 may be configured to perform the distance measurement of the objects 195, 196 based on measurement signals obtained from the detector 102. For example, the LIDAR system 103 may be configured to output a signal indicative of the distance and / or positioning of the objects 195, 196 with respect to the assembly 100. In some examples, LIDAR system 103 may also output a signal indicative of a velocity of objects 195, 196 and / or a material of objects 195, 196. In order to distinguish between the objects 195, 196 - that is, in order to provide a spatial resolution - the emitter 101 is arranged to emit the laser light 191, 192 at different angles. Depending on the set angle 110, the laser light 191, 192 is thereby reflected either by the object 196 or by the object 195. By the LIDAR system 103 receives information about the respective angle 1 10, the spatial resolution can be provided. In FIG. 1, the scan area within which the angles 10 1 can be varied is illustrated by a dotted line.

FIG. 1B illustrates aspects relating to the arrangement 100. FIG. 1B illustrates the arrangement 100 in greater detail than FIG. 1A.

In the example of FIG. 1B, the emitter 101 is implemented by a laser light source 599 and a scanning device 500. For example, the laser light source 599 could be a fiber laser or to be a laser diode. The assembly 100 also includes an actuator 900 configured to operate the scanning device 500. The scanning device 500 is configured to deflect the laser light 191, 192, which is emitted by the laser light source 599, so that it is emitted at different angles 110. The scanning device 500 may enable one-dimensional scanning or two-dimensional scanning of the environment.

The actuator 900 is typically electrically operable. The actuator 900 could include magnetic components and / or piezoelectric components. For example, the actuator could include a rotational magnetic field source configured to generate a magnetic field rotating as a function of time.

For controlling the actuator 900, a controller 950-for example an electrical circuit, a microcontroller, an FPGA, an ASIC, and / or a processor, etc.-is provided, which is configured to send control signals to the actuator 900. The controller 950 is in particular designed to control the actuator 900 in such a way that this scanning device operates to scan a specific angle range 110. The controller can implement a specific scan frequency. For example, different spatial directions with different scanning frequencies could be scanned. Typical scanning frequencies can be in the range of 0.5 kHz - 2.5 Hz, optionally in the range of 0.7 kHz - 1.5 kHz. The scanning can be carried out continuously in a continuous step-and-shoot technique.

In addition, in FIG. 1B, a positioning device 560 is provided. The positioning device 560 is configured to output a signal indicative of the emission angle with which the laser light 191, 192 is emitted. For this purpose, it would be possible, for example, for the positioning device 560 to perform a state measurement of the actuator 900 and / or the scanning device 500. For example, the positioning device 560 could also directly measure the emitted laser light 191, 192. The positioning device 560, in a simple implementation, could also receive control signals from the controller 950 and determine the signal based on the control signals. Combinations of the above techniques are also possible.

The LIDAR system 103 may use the signal provided by the positioning device 560 for scanned distance measurement of the objects. The LIDAR system 103 is also coupled to the detector 102. Based on the signal of the positioning device 560 and based on that detected by the detector 102 Laser light 191, 192, the LIDAR system 103 then make the distance measurement of the objects 195, 196 in the vicinity of the arrangement 100. For example, the LIDAR system 103 may implement the spatial resolution of the distance measurement based on the signal from the positioning device 560.

In one example, it would also be possible for the positioning device 560 to be connected to the controller 950 of the actuator 900 (not shown in FIG. 1B). Then, a control loop could be implemented wherein the scanning device 500 is controlled based on the signal from the positioning device 560. The control loop could be implemented analog and / or digital. This means that the controller 950 can control the actuator 900 based on the signal of the positioning device 560. Then, a reproducible scanning of the environment can be made possible. For example, For example, measurement points of the LIDAR measurement can be acquired repeatedly at the same emission angles. This can allow a particularly simple evaluation.

FIG. 2 illustrates aspects relating to the assembly 100. In particular, FIG. 3 Aspects related to the scanning device 500. In the example of FIG. 2, the assembly 100 includes an optical fiber 201. The optical fiber 201 implements the scanning device 500. The optical fiber 201 extends along a central axis 202. The optical fiber 202 includes a movable end 205 having an end surface 209. At an end opposite the movable end 205 (not shown in FIG. 2) of the optical fiber 201 The laser light 191, 192 is fed to the optical fiber 201. A connection can be used for this purpose. For example, the laser light source 599 could be disposed at the opposite end of the optical fiber 201 from the movable end 205. The laser light 191, 192 can then propagate through the optical fiber 201 and exit at the movable end 205 through the end face 209. A portion of the laser light may be reflected at the end 205: based on the reflected portion, a transit time measurement could be performed in the optical fiber 201, e.g. as reference measurement for the LIDAR distance measurement.

The assembly 100 also includes a fixation 250. For example, the fixation 250 could be made of plastic or metal. For example, the fixation 250 could be part of a housing that receives the movable end 250 of the optical fiber 201. The housing could e.g. a DPAK or DPAK2 housing.

The fixation 250 fixes the optical fiber 201 at a fixation point 206. For example, the fixation 250 may include the optical fiber 201 at the fixation site 206 by a clamp connection and / or be implemented a solder joint and / or an adhesive bond. In the region of the fixing point 206, the optical fiber 201 is therefore stationary or rigidly coupled to the fixing 250. In FIG. 2, a length 203 of the optical fiber 201 between the fixing point 206 and the movable end 205 is further shown. From FIG. 2 it can be seen that the movable end 205 is spaced from the fixing point 206. For example, in various examples, the length 203 could be in the range of 0.5 cm - 10 cm, optionally in the range of 1 cm - 5 cm, further optionally in the range of 1, 5 - 2.5 cm. For example, the length 203 could be in the range of 5 mm - 10 mm.

The movable end 205 is thus free in space. By this distance of the movable end 205 relative to the fixing point 206 can be achieved that the position of the movable end 205 of the optical fiber 201 relative to the fixing point 206 can be changed. In this case, it is possible, for example, to bend and / or twist the optical fiber 201 in the area between the fixing point 206 and the movable end 205.

FIG. 3A illustrates aspects relating to the assembly 100. In particular, FIG. 3A aspects related to the scanning device 500. In the example of FIG. 3A, the assembly 100 includes an optical fiber 201. The optical fiber 201 implements the scanning device 500. The example of FIG. 3A corresponds to the example of FIG. 2. FIG. 3A shows a dynamic state of the scanning device 500.

In the example of FIG. 3A, the end 205 of the optical fiber 201 is shown in a position 301 and a position 302 (dashed line in FIG. 3A). These positions 301, 302 implement extreme positions of the optical fiber 201: e.g. For example, a stop could be provided which prevents further movement of the end 205 beyond the positions 301, 302 (not shown in FIG. 3A). The optical fiber 201 may reciprocate between positions 301, 302, e.g. periodically. In the example of FIG. 3A corresponds to the position 301 of a bend 31 1. The position 302 corresponds to a bend 321. The bends 31 1, 321 have opposite signs.

As shown in FIG. 3A, depending on the position 301, 302, the laser light 191, 192 is emitted at different angles, ie, a bending angle range 1 10-1. For moving the optical fiber 201 between the positions 301, 302, the actuator 900 may be provided (the actuator 900 is not shown in FIG. 3A). While in FIG. 3A, a one-dimensional motion (in the plane of the drawing of FIG. 3A) would also be possible, a two-dimensional motion (with a component perpendicular to the drawing plane of FIG. By providing the bends 31 1, 321 in the positions 301, 302, it is achieved that the laser light 191, 192 is emitted over the bending angle range 1 10-1. This makes it possible to scan the surrounding area of the arrangement 100 by means of the laser light 191, 192. In the example of FIG. 3A, an exemplary radius of curvature 312 for the curvature 31 1 is also illustrated. In addition, an exemplary radius of curvature 322 for the bend 321 is illustrated. The radii of curvature 312, 322 are each approximately 1.5 times as large as the length 203 of the optical fiber 201 between the fixing point 206 and the movable end 205. In other examples, weaker curvatures 31 1, 321 or larger curvatures 31 1, 321 are implemented. In this case, weaker curvatures 31 1, 321 correspond to larger radii of curvature 312, 322, in particular with respect to the length 203.

Various implementations are based on the finding that a tradeoff between a large scan area and small bends 31 1, 321 can be desirable. On the one hand, small bends 31 1, 321 may be desirable in relation to a scanning frequency and / or a material fatigue of the optical fiber 201. On the other hand, large bends 31 1, 321 may be desirable with respect to a large scan area.

In some examples, it may be possible for the bends 31 1, 321 in the positions 301, 302 to have different radii of curvature 312, 322, depending on the position along the axis 202 of the optical fiber 201. For example, it would be possible for larger (smaller) radii of curvature 312, 322 to be present in positions 301, 302 near (at a distance from) the end 205 of the optical fiber 201, or vice versa. For example, it would be possible for curvature radii 312, 322 to be near (spaced from) the end 205 of the optical fiber at positions 301, 302 that have a positive (negative) radius of curvature 312, 322. In other words, it would be possible that the bends 31 1, 321 each have a turning point. Such a configuration of the bends 31 1, 321 can be achieved, for example, by a suitable interaction of the actuator 900 with the optical fiber 201. For example, a force action of the actuator 900 could act on the optical fiber 201 at a point closer to the end 205 than to the fixation site 206 (or closer to the fixation site 206). For example, a second order or higher order curvature mode could become resonant be stimulated. By means of such techniques it can be achieved that a particularly large scan area can be scanned by means of the laser light 191, 192.

FIG. 3B illustrates aspects relating to the assembly 100. In particular, FIG. FIG. 3B illustrates aspects related to the scanning device 500. In the example of FIG. 3B, the arrangement 100 includes an optical fiber 201. The optical fiber 201 implements the scanning device 500. The example of FIG. 3B corresponds to the example of FIG. 2. FIG. 3B shows a dynamic state of the scanning device 500. In the example of FIG. 3B, the end 205 of the optical fiber 201 is moved such that the optical fiber 201 moves in the area between the fixing point 206 and the movable end 205 between a first torsion 371 and a second torsion 372. This corresponds to a twist of the optical fiber 201 along the central axis 202. By providing the torsions 371, 372, it is achieved that the laser light 191, 192 can be radiated over a corresponding torsional angle range 1 10-2, e.g. in connection with a deflection unit (not shown in FIG. 3B) which redirects the laser light 191, 192 with respect to the central axis 202). This corresponds to the operation of a rotatable periscope. This makes it possible to scan the surrounding area of the arrangement 100 by means of the laser light 191, 192.

Again, a corresponding actuator configured to implement the various torsions 371, 372 may be provided. For example, those shown in FIG. 3B shown torsions 371, 372 correspond to extreme positions of the movable end 205. It would be possible, for example, to provide a corresponding stop which prevents further rotation of the movable end 205 beyond the torsions 371, 372 (not shown in FIG. 3B). Alternatively or additionally, it would also be possible for the actuator to be arranged in order to avoid a further rotation of the movable end 205 beyond the torsions 371, 372. In FIG. 3B, the angle range 1-10-2, which may be implemented, for example, in cooperation with a deflection unit (not shown in FIG. 3B) by means of the torsion 371, 372 of the movable end 205 of the optical fiber 201.

FIG. 4A illustrates aspects relating to the assembly 100. In particular, FIG. FIG. 4A illustrates aspects related to the scanning device 500. In the example of FIG. 4A, the assembly 100 includes an optical fiber 201. The optical fiber 201 implements the scanning device 500. The example of FIG. 4A basically corresponds to the example of FIG. 3A. A corresponding arrangement would also be for the implementation of FIG. 3B by means of torsions 371, 372 possible. In the example of FIG. 4A, the assembly 100 further includes a lens 400 that is rigidly connected to the fixture 250. The movable end 205 of the optical fiber 201 is arranged between the lens 400 and the fixation 250 in a corresponding space 450.

By means of the lens it is possible to collect a divergent beam cross section of the laser light 191, 192 (in FIG. 4A the beam cross section of the laser light 191, 192 is not shown). In particular, it can be achieved that the beam cross section of the laser light 191, 192 behind the lens 400 does not significantly increase as a function of the location with increasing distance to the movable end 205. As a result, a particularly high spatial resolution can be provided, for example, in connection with the LIDAR technique. The laser light 191, 192 is emitted in small solid angles.

While in the example of FIG. 4A, an implementation is shown in which the lens 400 is fixedly connected to the fixture 250 - that is, the end 205 of the optical fiber 201 moves relative to the lens 400 -, in other implementations it would also be possible for an alternative or additional lens to be stationary or rigidly with the end 205 and the surface 209 of the optical fiber 201 is coupled. It would thus be possible to provide a particularly simple optical system for avoiding the divergence of the laser light 191, 192.

While in the example of FIG. 4A, an implementation is shown in which only a single lens 400 is used, in other implementations it would also be possible to use a larger number of lenses 400, for example a lens system. For example, at least one condenser lens could be used. It would also be possible for the one or more lenses to implement fisheye optics.

By means of such techniques it may be possible to extend the scan area. In particular, this makes it possible to break the laser light 191, 192 away from the central axis 202 of the fiber 201 in the area of the fixing point 206 (as shown in FIG. 4A). As a result, a significant scanning range can nevertheless be achieved by a comparatively small deflection in the optical fiber 201. This in turn may allow to increase the scanning frequency at which the actuator 900 moves the optical fiber 201 back and forth between the positions 301, 302. For example, in some examples, it would be possible for the space 450 in which the optical fiber 201 is moving to be sealed airtight from the environment 451. For example, it would be possible for negative pressure to prevail in ambient 450 over the ambient pressure. It can thereby be achieved that the air resistance when moving the optical fiber 201 between the positions 301, 302 is particularly low. As a result, higher scanning frequencies with which the actuator 900 moves the optical fiber 201 back and forth between the positions 301, 302 can be achieved. In addition, material fatigue of the optical fiber 201 can be reduced. FIG. 4B illustrates aspects relating to the lens 400. In the example of FIG. 4B, the focal length 405 of the lens 400 is shown as a function of the position perpendicular to the optical axis of the lens 400. From FIG. 4B, it can be seen that focal length 405 varies as a function of position perpendicular to the optical axis. In the example of FIG. 4B, the path 305 is illustrated, followed by the end 205 of the optical fiber 201 moving between the positions 301, 302. From FIG. 4B, it can be seen that the focal length 405 of the lens 400 corresponds to the path 305. This means that the end 205 of the optical fiber 201 for different positions 301, 302 is located in the focal plane of the lens 400: the variable focal length 405 can be the variable distance of the end 205 of the optical fiber 201 from the lens 400 due to the curvatures 31 1, 321 for different positions 301, 302 compensate. As a result, a particularly good collection of the divergent laser light 191, 192 can take place through the lens 400.

Although in FIG. 4B again illustrates an implementation in which only a single lens 400 is present, it would also be possible in other examples to implement these techniques for more than one lens 400.

In the examples of FIGS. 4A and 4B, a lens 400 is provided, which remains stationary relative to the movable end 205 of the optical fiber 201. In other examples, it would also be possible that, alternatively or additionally, one or more lenses are provided, which are fixedly connected to the movable end 205 and therefore move along with movement of the movable end 205 with this.

FIG. 4C illustrates aspects relating to the assembly 100. In particular, FIG. 4C illustrates aspects relating to a lens 451 fixedly connected to the movable end 205 of the optical fiber 201. In the example of FIG. 4C is the lens 451 adjacent to the movable end 205 attached. The example of FIG. 4C could be used with the examples of FIGS. 4A and 4B are combined.

The lens 451 could be, for example, a gradient index (GRIN) lens or a ball lens. For example, the lens 451 could be glued or spliced. For better support of the lens 451, a sleeve could be placed around the fiber 201 in the region of the movable end 205; on this sleeve (not shown in FIG. 4C), the lens 451 could be supported. The lens 451 could, for example, have a diameter which is not greater than 500% of the diameter of the optical fiber 201 in the region of the movable end 205, preferably not greater than 250%, particularly preferably not greater than 150%. For example, the diameter of the lens 451 could be about 1 mm. Through the lens

451, for example, a diameter of the laser light 191, 192 of about 10 cm in 100 m can be achieved. It can thereby be achieved that the lens 451 has comparatively little mass: this in turn makes it possible to achieve that the movement of the movable end 205 through the actuator is simply possible. For example, with a torsion and / or curvature of the movable fiber 201 in the region between the fixing point 206 and the movable end 205, the lens 451 may perform the corresponding movement together with the end 205. Through the use of the movable with the movable end 205 movable lens 451 various effects can be achieved. On the one hand, it is possible that a complicated and large-area configuration of a stationary-remaining lens (cf. FIGS. 4A and 4B) can be avoided. Furthermore, it is possible that changes in the optical system induced by the movable end 205 of the optical fiber 201 and the stationary-remaining lens due to, for example, thermal effects can be avoided: For example, an offset between the lens remaining stationary and the lens movable end 205 due to thermal expansion or contraction can be avoided. As a result, a particularly stable construction can be ensured. Furthermore, it may be possible to determine particularly accurately the angle at which the light 191, 192 is radiated. Namely, by eliminating or reducing uncertainty by the spaced-apart stationary lens, it is possible to prevent additional interference from being caused by inaccuracies in the positioning of this spaced-apart stationary lens. FIG. 4C further illustrates aspects relating to a diverter unit 452. The diverter unit

452 is fixedly connected to the movable end 205 of the optical fiber 201. The deflection unit 452 is set up, the light 191, 192 after exiting the movable End 205 to deflect relative to the central axis 202. Within the optical fiber 201, the light 191, 192 is guided along the central axis 202. In FIG. 4C, an angle 452A is shown around which the light 191, 192 is deflected with respect to the central axis 202. In the example of FIG. 4C, this angle 452A is approximately 90 °. In other examples, larger or smaller angles could also be implemented, ranging, for example, from 10 ° to 170 °.

In the example of FIG. 4C, an implementation is shown in which the lens 451 is disposed between the deflection unit 452 and the end 205 of the optical fiber 201. In other examples, it would also be possible for the diverter 452 to be between the lens

451 and the end 205 of the optical fiber 201 is arranged.

It is not necessary that the lens 451 always in cooperation with the deflection unit

452 is implemented. Examples would also be possible in which either the lens 451 or the diverter unit 452 is used to form light 191, 192 exiting the end 205 of the optical fiber 201.

FIG. 5 illustrates aspects relating to the assembly 100. In particular, FIG. 5 Aspects Related to Positioning Device 560. In the example of FIG. 5, the positioning device 560 is arranged to measure the movement of the end 205 of the optical fiber 201. In particular, the positioning device 560 is arranged to measure the curvature 31 1, 321 of the optical fiber 201. In particular, the positioning device 560 is arranged to optically measure the curvature 31 1, 321 of the optical fiber 201. For this purpose, incident light 591 - for example with a different wavelength than the laser light 191, 192 - used. For example, the light 591 may be provided by a broadband light source. The spectrum of the light 591 may have, for example, a spectral width of not less than 50 nm, preferably not less than 150 nm, more preferably not less than 500 nm. Reflected light 592 - sometimes referred to as secondary radiation - is detected by a corresponding detector , The reflected light 592 is indicative of a curvature 31 1, 312 of the optical fiber 201 and thus the position 301, 302 of the end 205. Based on the reflected light 592, the signal indicative of the curvature 31 1, 321 can then be provided the optical fiber 201 is. For example, this signal may be used by LIDAR system 103. By means of the optical measurement, the emission angle under which the laser light 191, 192 is radiated can be determined particularly accurately. In the example of FIG. 5, the positioning device 560 is implemented by a fiber Bragg grating 51 1. The fiber Bragg grating 51 1 has an extension parallel to the central axis 202 of the fiber 201: Along this dimension, the refractive index of the material is periodically modulated. The fiber Bragg grating 51 1 is arranged in the fiber 201 between the fixing point 206 and the end 205. By a suitable arrangement of the fiber Bragg grating 51 1 in the optical fiber 201 can be achieved that the curvature 31 1, 321 of the optical fiber 201 results in a change in length of the fiber Bragg grating 51 1. For example, the fiber Bragg grating 51 1 could be spaced apart from the central axis 202 of the optical fiber 201 (not shown in FIG. 5). This change in length of the fiber Bragg grating 51 1 can in turn result in a change in the amplitude of the reflected light 592 in the range of the wavelengths which fulfill the Bragg condition. For this purpose, the periodicity of the fiber Bragg grating 51 1 is tuned to the wavelength of the light 591. The positioning device 560 may then be configured to determine the signal based on an amplitude of the reflected light 592. In particular, it may be possible to determine the amplitude of the reflected light 592 particularly precisely and / or particularly quickly. This may make it possible to determine the curvature 31 1, 321 particularly accurately. As a result, it may again be possible to determine the position of the end 205 or the angle 210 in the position particularly precisely. The periodicity of the fiber Bragg grating 51 1 may be different from the wavelength of the laser light 191, 192. Therefore, the propagation of the laser light 191, 192 is not significantly affected by the fiber Bragg grating 51 1.

The fiber Bragg grating 51 1 has a length 525 which corresponds approximately to 80% of the length of the optical fiber 201 between the fixing point 206 and the end 205. Other examples would also allow the length 525 to be at least 50% of the length 203, preferably at least 70%, particularly preferably at least 90%. By such an extension of the fiber Bragg grating 51 1 along the length 203, the curvature 31 1, 321 can be determined particularly accurately.

In some examples, it may be possible for the positioning device 560 to include an edge filter. By means of the edge filter, it may be possible to determine the amplitude of the reflected light 592 particularly fast. For example, a transmission peak of the edge filter may be arranged in the region of an edge of the reflection curve of the fiber Bragg grating 51 1. As a result, slight changes in length of the fiber Bragg grating 51 1 can lead to a strong variation in the amplitude passed through the edge filter. This allows the amplitude of the reflected light 592 be determined accurately and quickly. Fast sampling frequencies with which the position of the end 205 is determined can be achieved. For example, it would be possible for the positioning device 560 to be set up in order to update the signal with a sampling frequency that is at least 500 Hz, preferably at least 1 kHz, particularly preferably at least 1.5 kHz.

In the various examples described herein, it would be possible for the positioning device 560 to be configured to update the signal at a sampling frequency that is at least a factor of 1.5 greater than the scan frequency at which the actuator 900 terminates the 205 of the FIG Optical fiber 201 moves, preferably at least a factor of 2, more preferably at least by a factor of 3. This can be a very accurate determination of the angle 1 10, under which the laser light 191, 192 emitted. Continuous step-and-shoot techniques are possible. FIG. 6A illustrates aspects relating to the assembly 100. In particular, FIG. 6A Aspects related to the positioning device 560. In the example of FIG. 6A, the positioning device 560 is implemented by two fiber Bragg gratings 51 1, 512.

The fiber Bragg grating 51 1 is located in an optical fiber 501 -1, which is different from the optical fiber 201. The fiber Bragg grating 512 is located in an optical fiber 501 -2, which is also different from the optical fiber 201. In one example, the optical fibers 501 -1, 501 -2 are attached to the optical fiber 201 on opposite sides 251, 252 of the optical fiber 201. In another example, a multi-core fiber could be used to connect the optical fiber

201 and the optical fibers 501 -1, 501 -2.

The central axes 502-1, 502-2 of the optical fibers 501-1, 501-2 are parallel to the central axis

202 of the optical fiber 201. As a result, a curvature 31 1, 321 of the optical fiber 201 causes a corresponding curvature of the optical fiber 501 -1, 501 -2. For example, the curvature 31 1 in the counterclockwise direction (see FIG 3A) causes a compression of the optical fiber 501 -1 and thus a shortening of the fiber Bragg grating 51 1; the curvature 31 1 in the counterclockwise direction also causes an elongation of the optical fiber 501 -2 and thus an extension of the fiber Bragg grating 512. Due to the eccentric arrangement of the optical fiber 501 -1, 501 -2 with respect to the central axis 202, this shortening and Extension of the fiber Bragg gratings 51 1, 512 are particularly significant. Thereby, the position of the end 205 can be determined particularly accurately based on the light 592 reflected by the fibers 51 1, 512. Corresponding length changes can also be observed with a torsion 371, 372. FIG. 6B illustrates aspects relating to the assembly 100. In particular, FIG. FIG. 6B illustrates aspects related to the positioning device 560. In the example of FIG. 6B, the positioning device 560 is implemented by two fiber Bragg gratings 51 1, 512. The example of FIG. 6B is a plan view of the example of FIG. 6A.

FIG. 6C illustrates aspects relating to the assembly 100. In particular, FIG. 6C, aspects related to the positioning device 560. In the example of FIG. 6C, the positioning device 560 is implemented by four fiber Bragg gratings (not shown in FIG. 6C). The example of FIG. 6C basically corresponds to the example of FIGs. 6A, 6B. However, in the example of FIG. 6C, a larger number of fibers 501 -1 - 501 -4 are provided with respective fiber Bragg gratings (not shown in FIG. 6C), e.g. again as multi-core fibers. By means of the implementation of FIG. In particular, movements of the end 205 in two dimensions (in the drawing plane of FIG. 6C) can be detected. A two-dimensional scan area can be monitored. For example, the fiber Bragg gratings in the fibers 501 -1, 501 -2 have a curvature sensitivity along that shown in FIG. 6C with x direction on. For example, the fiber Bragg gratings in the fibers 501 -3, 501 -4 have a sensitivity to curvatures along that shown in FIG. 6C with y direction on. FIG. FIG. 7 illustrates aspects relating to the assembly 100. In particular, FIG. 7 Aspects Related to Positioning Device 560. In the example of FIG. 7, the positioning device 560 is implemented by four fiber Bragg gratings 51 1 -514.

The fiber Bragg gratings 51 1, 513 are located in the fiber 501 -1. Fiber Bragg gratings 512, 514 are in the fiber and 501 -2. In some examples, it would also be possible for there to be more than two serially connected fiber Bragg gratings in the respective fibers 501 -1, 501-2, 201 (see FIGURE 8A).

By using different lattice constants for the respective serially connected fiber Bragg gratings 51 1 -514, the individual fiber Bragg gratings 51 1 -514 can be individually controlled. For this purpose, enough broadband light can be used.

In particular, for a case in which the radius of curvature as a function of position is variable along the length of the fiber 201, then by comparing the amplitudes of the light reflected from the serially arranged fiber Bragg gratings 51 1, 513 and 512, 514, respectively 592 a particularly accurate determination of the position of the end 205 of the optical fiber 201 done. For example, it would be possible to do that based on a Difference of the amplitudes of the light 592 reflected by the serially arranged fiber Bragg gratings 51 1, 513 and 512, 514, respectively, the signal which is indicative of the position 301, 302 of the end 205 of the optical fiber 201 is determined by the positioning device 560 , FIG. 8B illustrates aspects relating to the assembly 100. In particular, FIG. 8B, aspects related to the positioning device 560. In the example of FIG. 8B, the positioning device 560 is implemented by a PSD 552. The PSD 552 may be implemented isotropically or discretely. For example, the PSD 552 may include multiple pixels, or include, for example, a PIN diode.

In the example of FIG. 8B, the assembly 100 includes the lens 451, which is fixedly connected to the movable end 205 of the optical fiber 201. The PSD 552 is configured to measure the laser light 191, 192 exiting the end 205 of the optical fiber 201. The PSD 552 measures the position of the laser light 191, 192 on its sensor surface. For this purpose, a lens 551 is provided, which focuses the light 191, 192 on the sensor surface of the PSD 552. The arrangement 100 furthermore comprises a beam splitter 801 for this purpose. Also, the beam splitter 801 is fixedly connected to the end 205 of the optical fiber 201. The beam splitter 801 is arranged to direct a partial beam path 802 of the light 191, 192 to the PSD 552.

By a corresponding arrangement of the PSD 552 with respect to the movable end 205 can be achieved that the position of the light spot on the sensor surface of the PSD 552 indicative of the position of the movable end 205 of the optical fiber 201 and for the exit angle of the laser light 191, 192 is. Therefore, based on this large measurement, the signal indicative of the position of the movable end 205 and, in particular, indicative of the curvature 31 1, 321 and / or the torsion 371, 372 of the optical fiber 201 in the region between the fixing point 206 can be provided and the movable end 205 is. The signal may be indicative of the exit angle of the laser light 191, 192. By arranging the beam splitter 801 in the beam path of the exiting laser light 191, 192 behind the lens 451, it can be achieved that possible influences of the lens 451 are taken into account in the measurement by the PSD 552. For example, an offset of the exiting laser light 191, 192 may be considered due to the geometry of the attachment of the lens 451 to the movable end 205. In particular, such a drift over the lifetime due to a time-variable offset of the exiting laser light 100 a 90, 192 are taken into account. The long-term stability can be increased thereby. FIG. 8C illustrates aspects relating to the assembly 100. In particular, FIG. 8C, aspects related to the positioning device 560. In the example of FIG. 8C, the positioning device 560 is implemented by a PSD 552. The example of FIG. 8C basically corresponds to the example of FIG. 8B. In the example of FIG. 8C, the beam splitter 801 is arranged between the deflection unit 452 and the lens 451. In other examples, it is also possible that, for example, the deflection unit 452 is arranged between the beam splitter 801 and the lens 451. FIG. 9 illustrates aspects relating to the assembly 100. In particular, FIG. 9 Aspects Concerning the Actuator 900. In the example of FIG. 9, actuator 900 included a coil assembly 901 that includes conductor turns and is configured to generate a magnetic field in the region of optical fiber 201. The optical fiber 201 is coated with a magnetic material 903, for example by sputtering. It would also be possible to glue or solder a magnet etc. The magnetic material is eg ferromagnetic or paramagnetic or diamagnetic.

In addition, actuator 900 included a guide along which end 205 is guided one-dimensionally. This means that the actuator 900 according to the example of FIG. 9 is configured to one-dimensionally scan the optical fiber 205. By applying a time-varying current to the coil assembly 901, a time-varying magnetic field can be generated in the region of the magnetic material 903. As a result, the optical fiber 205 is deflected along the guide 902. In particular, the optical fiber 205 can be scanned between the positions 301, 202.

It would be possible for the controller to be arranged to drive the actuator 900 to scan the end 205 of the optical fiber 201 between the reversal positions 301, 302 at a scan frequency of at least 500 Hz, optionally at least 700 Hz, more optionally at least 1 , 2 kHz scans. Scanning may mean, in the various examples described herein, that the controller 950 repeatedly drives the actuator 900 to periodically cause movement of the end 205 for multiple repetitions.

However, in other examples, it would also be possible for the actuator 900 to be configured to scan the optical fiber 201 two-dimensionally. The guide 902 can then be dispensable. FIG. 10A illustrates aspects relating to the assembly 100. In particular, FIG. 10A illustrates aspects related to the actuator 900. In the example of FIG. 10A includes the actuator

902 orthogonal coil pairs 901 (only one coil pair 901 is shown in FIG 10A; the further orthogonal coil pair is arranged in a plane perpendicular to the plane of the drawing). By alternately energizing the orthogonal coil pairs 901, a two-dimensional movement of the end 205 of the optical fiber 201 can be achieved.

FIG. 10B illustrates aspects relating to the assembly 100. In particular, FIG. 10B, aspects relating to the actuator 900. In the example of FIG. 10B, the actuator 902 on the opposite sides 251, 252 of the optical fiber 201 mounted lever 951, 952. The levers 951, 952 extend perpendicular to the central axis 202 of the optical fiber 201. The levers 951, 952 could be made of plastic, silicon, glass, etc., for example. On the levers 951, 952 is spaced from the central axis 202 each have a magnet

903 provided. As a result, an eccentric deflection of the levers 951, 952 with respect to the central axis 202 can take place by means of a magnetic field generated by the coils 901.

As a result, a torque can act on the fiber 201. As a result, in particular, a torsion of the fiber 201 in the region between the fixing point 206 and the movable end 205 can be effected. FIG. 10C illustrates aspects relating to the assembly 100. In particular, FIG. 10C, aspects related to the actuator 900. In the example of FIG. 10C, the actuator 900 includes a rotary magnetic field source (not shown in FIG. 10C) configured to generate a magnetic field 961 which is a function of time in a plane defined perpendicular to the central axis 202 of the fiber 201 (drawing plane of FIG. above) rotates. In FIG. 10C, an angle 962 is plotted, which the magnetic field 961 assumes at any desired time.

In the example of FIG. 10C, the actuator 900 further comprises two magnets 903. The magnets 903 may be adhered to the optical fiber 201. Sputtering would be possible. The magnets 903 could be formed as thin films. A first magnet 903 is disposed on the side 251 of the fiber 201. A second magnet 903 is disposed on the opposite side 252 of the fiber 201. The two magnets 903 are poled in opposite directions. In the example of FIG. 10C, the magnetization of the first magnet 903 (shown on the left side in FIG. 10C) is oriented out of the plane of the drawing; the magnetization of the second magnet 903 (shown in time in FIG. 10C) is oriented in the plane of the drawing. Therefore, the magnetic field 961 causes inversely oriented force actions in the plane perpendicular to the central axis 202 (drawing plane of FIG. 10C). As a result, in particular, a torsion of Fiber 201 can be effected in the region between the fixing point 206 and the movable end 205.

By sizing the angle 962, the scanning area can be adjusted due to the torsion of the optical fiber 201. This is shown in FIG. 10C, illustrated below. In FIG. 10C, the course of the angle 962 of the rotary magnetic field 961 is shown below as a function of time. From FIG. 10C, it can be seen that the angle 962 is periodically varied between maximum values. The torsion of the fiber 201 follows, for example, the angle 962, so that the angle range 1 10-2 defined by the torsion corresponds to the stroke of the angle 962.

For example, as a rotary magnetic field source, a system of a plurality of coils whose coil axes include angles of, for example, 120 ° with each other could be used. By time-delayed driving of the coils thereby the rotating magnetic field can be generated.

FIG. FIG. 1 illustrates aspects relating to the assembly 100. In particular, FIG. 1 1 Aspects Related to the Actuator 900. In the example of FIG. 1 1, the actuator 902 comprises piezoelectric conductors 913 attached to the different sides 251, 252 of the optical fiber 201. When current flows through the piezoelectric conductors 913, they change their length so that the curvature 31 1, 312 and the movement of the optical fiber 201 between, respectively the positions 301, 302 results.

FIG. 12A illustrates aspects relating to the arrangement 100. In the example of FIG. 12A, the arrangement 100 includes the laser 599, the broadband light source 1201 for generating the light 591, having a wavelength tuned to the grating periodicity of the one or more fiber Bragg grids 51 1 -516, and a detector 1202 can detect the light 592 reflected from the one or more fiber Bragg gratings. For example, detector 1202 may include one or more edge filters. The arrangement 100 further includes a multiplexer 1250 configured to couple the laser light 191, 192 of the laser light source 599 and the light 591 of the broadband light source 1201 into the optical fiber 201. The multiplexer 1250 may also direct the light 592 reflected from the one or more fiber Bragg gratings to the detector 1202.

While in the example of FIG. 12A is a scenario in which only the optical fiber 201 is present, examples with multiple dedicated optical fibers 501 -1 - 501 -4 for the fiber Bragg grating (s) discussed above would be accordingly possible. In the example of FIG. 12A, the scanning device with the movable end 205 of the optical fiber 201 is arranged at a distance from the light sources 599, 1201. For example, the length of the optical fiber 201 may be at least 0.1 m, optionally at least 0.5 m, further optionally at least 2 m. This allows a flexible positioning of the scanning device 500 relative to the laser light source 599 and / or the broadband light source 1201. In particular, the scanning device 500 can be integrated in a very space-saving manner. To compensate for the transit time within the optical fiber 201, the transit time of the laser light in the optical fiber 201 can be measured. For this purpose, for example, the reflection of the laser light 191, 192 can be used at the end 205 of the optical fiber 201 in order to measure in the region of the laser light source 599 by means of a corresponding detector, the reflected laser light.

In the example of FIG. 12A, the detector 102 for detecting the laser light 191, 192 reflected by the objects 196, 195 in the vicinity of the arrangement 100 could, for example, be arranged next to the scanning device 500 (the detector 102 is not shown in FIG. 12A). In such an example, it would be possible for the detector 102 to output an electrical signal. Therefore, it is not necessary for the signal of the reflected light to be returned via the optical fiber 201.

FIG. 12B illustrates aspects relating to the arrangement 100. In the example of FIG. 12B, the laser light 191, 192 reflected by the objects 196, 195 is detected via the optics of the scanning device 500. For example, the reflected light 195, 196 could be coupled into the optical fiber 201 via the lens 400 or via the lens 451 , Then, it is possible for the detector 102 to be located behind the multiplexer 1250. The example of FIG. 12B could be used with fiber Bragg sensors 1201, 1202 according to FIG. 12A combined.

Typically, the highest intensity of the reflected laser light 195, 196 occurs along the same optical path along which the laser light 191, 192 coupled out primarily from the optical fiber 201 reaches the corresponding object 195, 196. Therefore, a technique according to FIG. 12B have a particularly high sensitivity.

In an example according to FIG. 12B, it may be desirable if the speed of movement of the movable end 205 of the optical fiber 201 is limited. In particular, it can be ensured in such a way that directly reflected laser light 191, 192 can be coupled into the optical fiber 201 before the movable end 205 of the optical fiber 201 has moved. Typical distances between the movable end 205 of the optical fiber 201 and the objects 195, 196 may, for example, be in the range of 100 m to 200 m. Therefore, it may be desirable for the controller 950 to be configured to implement scan frequencies in the range of 500 Hz to 2.5 kHz in the drive of the actuator 900, optionally in the range of 700 Hz to 1.5 kHz.

Typically, the modes of movement of the region of the optical fiber 201 between the fixing point 206 and the movable end 205 have natural frequencies in the corresponding frequency range. Therefore, it may be possible to allow resonant driving of the optical fiber 201 while at the same time enabling the coupling of the reflected laser light 191, 192 over the same optical path.

FIG. 12C illustrates aspects relating to the arrangement 100. In the example of FIG. 12C, the reflected laser light detector 191, 192 is implemented separately from the scanning device 500. In particular, there is no detection of reflected laser light 191, 192 fed back into the optical fiber 201. Such an arrangement makes it possible to use particularly large converging lenses to implement a detector 102 with high sensitivity. The example of FIG. 12C could be combined with fiber Bragg sensors 1201, 1202 according to FIG. 12A combined.

FIG. 13 illustrates aspects relating to the arrangement 100. In the example of FIG. 13, there are two optical fibers 201-1, 201-2 and two scanning devices 500-1, 500-2. As a result, it is possible to reuse the light sources 599, 1201 for scanning different surrounding areas by means of a plurality of scanning devices 500-1, 500-2. For example, For example, the scanning device 500 - 1 could be attached to a front of a vehicle and the scanning device 500 - 2 attached to the rear of a vehicle. In the example of FIG. 13, the optical fiber 201 -1, 201 -2 are connected to the multiplexer 1250. It would also be conceivable to couple the optical fibers 201-1, 201-2 via a fiber separator 1400 (compare FIG.

The examples of FIGS. 13 and 14 could with fiber Bragg sensors 1201, 1202 of FIG. 12A combined. FIG. 15 is a flowchart of a method according to various examples. In block 5001, laser light is injected into a second end of an optical fiber.

In block 5002, the opposite first end of the optical fiber is moved. Continuous step-and-shoot techniques can be used. The movable first end of the optical fiber can be moved in such a way that a curvature and / or torsion of the optical fiber in the region of the movable end is achieved. As a result, the angle at which laser light is emitted from the optical fiber can be changed. In block 5003, a LIDAR distance measurement is optionally implemented based on the ambient scanning implemented by the laser light in block 5002. Also, applications such as projecting light or endoscopy could be implemented.

FIG. 16 illustrates aspects related to the movement of the movable end 205 of the optical fiber 201. In the example of FIG. 16, the amplitude of the deflection of the optical fiber 201 is shown for various positions between the fixing point 206 and the movable end 205. In the example of FIG. 16, the amplitude of deflection of the optical fiber 201 is shown for the first-order eigen-mode (solid line) and the second-order eigen-mode (broken line). From FIG. 16 it can be seen that smaller radii of curvature and thus larger angles 1 10-1 under which the laser light 191, 192 is emitted can be implemented by means of the second-order eigenmode. Typically, the second order eigenmode has a higher natural frequency than the first order eigenmode. Moreover, it has been observed that the material loading of the material of the optical fiber 201 is lower for the second order eigenmode than for the first order eigenmode. In particular in the region of the fixing point 206, a lower material load in connection with the second-order eigenmode could be achieved. Therefore, in some examples, it is possible for the actuator 900 to be configured to resonantly move the optical fiber 201 in the second-order or higher eigen mode. FIG. 17 illustrates aspects relating to the assembly 100. In the example of FIG. 17, the assembly 100 includes a housing 1700 having a translucent element 1701. The laser light 191, 192 emerging from the movable end 205 of the optical fiber 201 can exit through the light-transmissive element 1701, for example a plastic disk or a glass pane. In some examples, the translucent element 1701 could have a refractive power to implement a lens (not shown in FIG. 17). For example, the translucent element 1701 could be implemented by the lens 400 (see FIGS. 4A, 4B) in the example of FIG. 17 is the area in which the movable end 205 of the optical fiber 201 moves evacuated. This means that the space 450 between the translucent member 1701 and the fixation 250 is airtight. Thereby, the movement of the movable end 205 can be implemented without air friction. In addition, external interference can be avoided.

For example, the housing 1700 could have passive temperature compensation. For example, the housing 1700 could have heat storage, which can reduce large temperature fluctuations.

For example, the housing 1700 could have active and / or passive shock absorption. As a result, impulses from outside the assembly 100 could be absorbed or reduced in amplitude, so that a negative influence on the movement of the movable end 205 of the optical fiber 201 can be reduced.

In the example of FIG. 17, the laser light source 599 and the detector 102 are also disposed in the housing 1700. In other examples, the laser light source 599 and / or the detector 102 could be located outside of the housing 1700. In such a case, it would be possible for the housing 100 to have an optical plug contact.

FIG. Fig. 18 illustrates aspects relating to two-dimensional scanning of an environment region extending along two orthogonal spatial directions x, y. In the example of FIG. 18, an environment region 1800 is scanned that has two-dimensional extent. The surrounding area 1800 may be e.g. are obtained by overlaying two one-dimensional scans by a Lissajous pattern.

The torsion angle range 1 10-2 is thereby achieved by the torsion of the optical fiber 201 in the region between the fixing point 206 and the movable end 205. The torsion angle range 1 10-2 is greater than the bending angle range 1 10-2, which is achieved by the curvature of the optical fiber 201. It has been observed that particularly good results can be achieved if the torsion angle range 1 10-2 is greater by at least a factor of 2 than the bending angle range 1 10-1, optionally by at least a factor of 3.5, further optionally by at least a factor of 5.

For example, the torsion angle 1 could be 10-2> 90 °, optionally> 140 °, further optional> 170 °. A smaller angle range 1 10-1 is due to the curvature of the optical fiber 201 reaches in the area between the fixing point 206 and the movable end 205. For example, the curvature angle range 1 10-1 could be between 10 ° and 60 °.

Such an implementation of the surrounding area 1800 is based on the knowledge that due to the torsion of the optical fiber 201, a particularly efficient scanning of large angular ranges 110-2 can be achieved. In particular, in such an implementation, the direct feedback of reflected laser light 191, 192 can be easily made possible. At the same time, by combining with the curvature of the optical fiber 201, two-dimensional scanning can be enabled.

Of course, the features of the previously described embodiments and aspects of the invention may be combined. In particular, the features may be used not only in the described combinations but also in other combinations or per se, without departing from the scope of the invention.

While various examples have been described above with respect to a LIDAR application, in other examples it would also be possible to implement other applications. Examples include e.g. a projector with an RGB light source etc.

Claims

1 . An assembly (100) comprising:

an optical fiber (201, 201-1, 201-2) having a first end (205) and a second end,

a fixation (250) which fixes the optical fiber (201, 201-1, 201-2) at a fixing point (206) between the first end (205) and the second end,

a terminal configured to supply light (191, 192) to the second end of the optical fiber (201, 201-1, 201-2), and

at least one actuator (900, 901 - 903, 913) arranged to perform the

Light fiber (201, 201 -1, 201 -2) in the area between the fixing point (206) and the first end (205) between a first twist (371, 372) and a second twist (371, 372) to move.

2. Arrangement (100) according to claim 1, further comprising:

a lens (451) fixedly connected to the first end (205) of the optical fiber (201, 201-1, 201-2), and

a deflection unit (452) fixedly connected to the first end (205) of the optical fiber (201, 201-1, 202-2) and arranged to move the light (191, 192) with respect to the central axis (202) the light fiber (201, 201 -1, 201 -2) to redirect.

3. Arrangement according to claim 1 or 2,

wherein the at least one actuator (900, 901 - 903, 913) is further arranged to connect the optical fiber (201, 201 - 1, 201 - 2) in the region between the fixing point (206) and the first end (205) between a first Curvature (31 1, 321) and a second

Curvature (31 1, 321) to move.

4. Arrangement according to claim 3,

wherein the at least one actuator (900, 900-903, 913) is adapted to the

Optical fiber (201, 201-1, 201-2) between the first curvature (31 1, 321) and the second curvature (31 1, 321) resonantly in a second order or higher eigenmode to move.

The assembly (100) of claim 3 or 4, further comprising:

a controller (950) arranged to drive the at least one actuator (900, 901 - 903, 913) to cause the optical fiber (201, 201 - 1, 201 - 2) to pass over one of the optical fibers (201, 201 - 1, 201 - 2) Torsion angle range (1 10-2) between the first torsion (371, 372) and the second torsion scans and over a bend angle range (1 10-1) between the first curvature (31 1, 321) and the second curvature ( 31 1, 321),

wherein the torsion angle range (1 10-2) is optionally at least a factor 2 greater than the bending angle range (1 10-1), further optionally by at least a factor of 3.5,

wherein the torsion angle range (100-2) is optionally greater than 90 °, optionally greater than 140 °, further optionally greater than 170 °.

6. Arrangement (100) according to one of the preceding claims, which further comprises:

a positioning device (560) arranged to output a signal indicative of a radiation angle of the light (191, 192) from the array (100),

wherein the positioning device is adapted to the angle of emission of the light

(191, 192) to be measured optically.

7. Arrangement (100) according to claim 6,

wherein the positioning device (560) comprises a position sensitive detector (552), PSD, arranged to emit the light (191, 192) emerging from the first end (205) of the optical fiber (201, 201-1, 201-2) ) to eat,

wherein the positioning device (560) further comprises a beam splitter (801) fixedly connected to the end (205) of the optical fiber (201, 201-1, 201-2) and configured to form a partial beam path (802) of the optical fiber directing light (191, 192) exiting the first end (205) of the optical fiber (201, 201-1, 201-2) to the PSD.

8. Arrangement (100) according to claim 6 or 7,

wherein the positioning device (560) comprises at least one fiber Bragg grating (51 1 -516).

The assembly (100) of claim 8, further comprising:

at least one further optical fiber (501 -1, 501 -2) connected to the optical fiber (201, 201)

1, 201 -2) and runs parallel to this,

wherein the at least one fiber Bragg grating (51 1 -516) is arranged in the at least one further optical fiber (201, 201 -1, 201 -2).

10. Arrangement (100) according to one of the preceding claims, wherein the at least one actuator (900, 901 - 903, 913) comprises at least one eccentrically deflected lever (951, 952), which is perpendicular to a

Central axis (202) of the optical fiber (201, 201 -1 - 201 -2) extends, and / or

wherein the at least one actuator (900, 901 - 903, 913) at least one

Rotary magnetic field source and two oppositely poled magnets comprises, the

different sides (251, 252) of the optical fiber (201, 201 -1, 201 -2) are arranged.

1 1. An assembly (100) according to any one of the preceding claims, further comprising:

- A LIDAR system (103), which is adapted to perform based on the light (191, 192) a scanned distance measurement of objects (195, 196) in the vicinity of the arrangement (100).

12. A method comprising:

Feeding light into a second end of an optical fiber,

- Fixing the optical fiber between a first end of the optical fiber and the second

End of the optical fiber, at a fixing point of the optical fiber, and

Moving the optical fiber in the region between the fixing point and the first end between a first twist and a second twist.

13. A method comprising:

- Scanning light (191, 192) by an optical fiber (201, 201 -1, 201 -2) having a first end (205) and a second end, wherein the optical fiber by means of a fixation

(205) is fixed at a fixing point (206) between the first end (205) and the second end, and

Moving the optical fiber (201, 201-1, 201-2) in the area between the fixing point

(206) and the first end (205) between a first twist (371, 372) and a second twist (371, 372).