WO2020200807A1

WO2020200807A1 - Laser emitting device for emitting pulsed laser light strips

Info

Publication number: WO2020200807A1
Application number: PCT/EP2020/057599
Authority: WO
Inventors: Ho-Hoai-Duc Nguyen; Spandan Shroff
Original assignee: Valeo Schalter Und Sensoren Gmbh
Priority date: 2019-04-02
Filing date: 2020-03-19
Publication date: 2020-10-08
Also published as: DE102019108593A1

Abstract

The invention relates to a laser emitting device (30) for emitting pulsed laser light strips in a horizontal emission angular range, in particular for a LiDAR-based surroundings sensor for use in a vehicle (32), comprising a laser light source (34) for generating pulsed laser beams (36), a laser beam spreading unit (38) which spreads the pulsed laser beams (36) in the vertical direction in order to form pulsed laser light strips (40) with a specified angular spread range (α). The pulsed laser light strips (40) have an irregular intensity distribution over the length (46) of the strips with an intensity maximum (48) in the center of the angular spread range (α). The laser emitting device also comprises a deflecting mirror (52) which is designed to be pivotal about a vertical axis in order to deflect the pulsed laser light strips (40) in the horizontal angular emission range, wherein the laser emitting device (30) is designed to emit the pulsed laser light strips (40) such that the intensity maximum (48) lies substantially on a horizontal plane, and the laser emitting device (30) is designed to emit the pulsed laser light strips (40) with an intensity distribution which has an intensity maximum (48) that is vertically displaced from the center of the angular spread range (α). The invention additionally relates to a LiDAR-based surroundings sensor, in particular for use in a vehicle (32), comprising the aforementioned laser emitting device (30) and a receiving unit for receiving reflections of the pulsed laser light strips (40) emitted by the laser emitting device (30) in the emission range. The invention additionally relates to a method which is carried out in a corresponding manner using the laser emitting device (30).

Description

Laser emitting device for emitting pulsed laser light strips

The present invention relates to a laser emitting device for emitting pulsed laser light strips in a horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle, comprising a laser light source for generating pulsed laser beams, a laser beam spreading unit which pulsates the pulsed laser beams

Laser light stripes spreads open in the vertical direction with a predetermined spreading angle range, the pulsed laser light stripes having a non-uniform

Have intensity distribution over their length with an intensity maximum in the middle of the spreading angle range, and a deflection mirror, which is designed to be pivotable about a vertical axis, around the pulsed laser light strips in the

deflect horizontal radiation angle range, wherein the laser emitting device is designed to emit the pulsed laser light strips such that the

Intensity maximum lies essentially in a horizontal plane,

The present invention also relates to a LiDAR-based environment sensor, in particular for use in a vehicle, with one of the above

Laser emitting device, and a receiving unit for receiving reflections of the pulsed laser light strips emitted by the laser emitting device in the emission area.

The present invention further relates to a method for emitting pulsed laser light strips in a horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle, comprising the steps of generating pulsed laser beams, spreading the pulsed ones

Laser beams to pulsed laser light strips with a given

Spread angle range in the vertical direction, the pulsed laser light strips having an uneven intensity distribution over their length with a

Intensity maximum in the middle of the spread angle range, deflection of the pulsed laser light strips in the horizontal beam angle range by pivoting a deflection mirror around a vertical axis, and emission of the pulsed laser light strips in such a way that the intensity maximum lies essentially in a horizontal plane. With LiDAR-based environment sensors, objects in an environment are recorded according to the so-called "time-of-flight" principle (ToF). Individual laser pulses are emitted by a laser emitting device and reflections of these laser pulses on the objects in the vicinity are received and evaluated by the receiving unit. From a time difference between the emission of the laser pulse and the reception of its reflection on the objects in the

Environment, the distance to the respective object can be detected. In addition, an intensity of the received reflections can be determined in order to gain additional information about a condition of the object.

The laser emitting device of such a LiDAR-based environment sensor is shown schematically in FIG. The laser emitting device 10 comprises a laser light source, not shown here, for generating pulsed laser beams. The pulsed laser beams are spread or widened in a laser beam spreading unit 12 in a vertical direction with a spreading angle range a, so that they form a vertically aligned laser light strip 14 or laser beam. In addition, various optical elements such as lenses and mirrors,

For example, to collimate the laser beam or the laser light strip 14, be arranged in the light path of the emitted laser beam. The laser light strip 14 is directed onto a movable deflection mirror 16 which can be pivoted about a vertical axis 18.

In the laser emitting device 10 shown in FIG. 1, the laser light strip 14 has, for example, a spreading angle range a of 26 °, while the deflection mirror 16 can be pivoted in an angle range of +/- 37.5 °. In accordance with the vertical spreading direction, the spreading angle range a thus defines a vertical field of view 20, shown in FIG. 2, of the LiDAR-based environmental sensor, which is covered by the laser emitting device 10 with the laser light strips 14. In FIG. 1, the vertical field of view 20 is indicated with an angular range of + β ° to -β ° with +/- 13 ° based on a central region o °.

The spread angle range a indicates a divergence of the pulsed laser light strips 14. As shown in FIGS. 2 and 3, the spreading of the pulsed laser light strips 14 results in an intensity 22 with a non-uniform one Intensity distribution over its length 24 with an intensity maximum 26 in the middle of the spread angle range a. The intensity 22 drops from the intensity maximum 26 to both the edges + β ° and -β ° of the spread angle range a. The length 24 is to be understood here as a relative indication, since the pulsed laser light strips 14 have a greater length 24 with increasing distance from the laser beam spreading unit 12.

The combination of the vertical laser light strips 14 and the movement of the deflecting mirror 16 about the vertical axis 18 makes it two-dimensional

Radiation area covered. Overall, the laser emitting device 10 can cover a horizontal angle range of 150 ° and a vertical angle range of 26 °.

The laser light stripe 14 is typically emitted via an optical emitting element (not shown here) which deflects the pulsed laser light stripes 14 in such a way that the central area o ° of the vertical spread angle area a with the intensity maximum 26 is horizontal. When the laser light strips 14 are emitted in a direction obliquely upwards, the optical

The emitting element thus deflects the pulsed laser light strips 14 in an opposite direction, i. downward. The optical radiating element is usually designed as a prism.

The intensity maximum 26 of the pulsed laser light strips 14 is thus directed into the horizontal by the optical emitting element. This means that the LiDAR-based

Environment sensor its greatest range in the horizontal direction. The vertical angular range of 26 ° thus extends 13 ° up and down from the horizontal plane.

The LiDAR-based environment sensor also includes a receiving unit, not shown here, for receiving reflections of the laser pulses emitted by the laser emitting device in the emitting area. The receiving unit has a plurality of receiving elements for receiving light with the wavelength of the pulsed laser beams, which are arranged in a matrix-like manner in a two-dimensional field. In addition, the receiving unit can have optical elements in order to guide the reflections in a suitable manner onto the receiving units. Individual, vertical rows of the receiving units can be selectively activated in accordance with an angular position of the laser light strip for receiving the reflections of the emitted laser pulses. In the vertical direction, the reflections are directed in a suitable manner to the receiving units so that the reflections can be assigned to a vertical angular position. Current LiDAR-based environmental sensors achieve a resolution of 1.8 °, for example, in the vertical direction, which is achieved here with sixteen reception channels. Due to the laser light strip, for example 120 receiving units are required to implement the sixteen receiving channels. In the horizontal direction, angle resolutions of 0.1 ° to 0.3 °, for example, are possible through the selective activation of the receiving units, the number of receiving units in the horizontal direction typically resulting from the horizontal angular range of the LiDAR-based environmental sensor and the resolution. This is necessary, for example, because the reflections overlap.

There are different types of LiDAR-based environmental sensors

Challenges. A challenge with current LiDAR-based ones

Environmental sensors is the so-called "smiley" effect, i.e. the detection of the reflections in the environment takes place with a distortion. As a result, the detection in the horizontal direction cannot take place with horizontal lines, but rather the lines are distorted in the manner of a segment of an arc depending on their horizontal position. This complicates the evaluation of the received reflections and the assignment of the received reflections of the detected objects to positions in the surroundings of the vehicle. The smiley effect results from a corresponding distortion when the pulsed laser light strips are emitted

Laser beam device.

Based on the above-mentioned prior art, the invention is based on the object of developing a laser emitting device for emitting pulsed laser light strips in a horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle, a LiDAR-based environment sensor with such a laser emitting device and to specify a method for the emission of pulsed laser light strips in a horizontal emission angle range, which reliably captures the surroundings enable and the appearance of the so-called "smiley" effect when the laser light strips are emitted and reflections from the emitted light are received

Reduce laser light streaks on objects in the vicinity.

The object is achieved according to the invention by the features of

independent claims. Advantageous embodiments of the invention are specified in the subclaims.

According to the invention, a laser emitting device for emitting pulsed laser light strips in a horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle, is thus specified, comprising a laser light source for generating pulsed laser beams, a laser beam spreading unit which pulsed the pulsed laser beams

Intensity maximum lies essentially in a horizontal plane, and wherein the laser emitting device is designed, the pulsed laser light strips with an intensity distribution, the intensity maximum from the center of the

Spread angle range is shifted vertically to radiate.

According to the invention, a LiDAR-based environment sensor, in particular for use in a vehicle, with an above laser emitting device, and a receiving unit for receiving reflections from the

Laser emitting device in the emitting area emitted pulsed

Laser light strips indicated.

A method for emitting pulsed radiation is also according to the invention

Laser light strips in a horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle, comprising the steps of generating pulsed laser beams, spreading the pulsed laser beams into pulsed laser light strips with a predetermined spreading angle range in the vertical direction, the pulsed laser light strips having a non-uniform intensity distribution over their length with a

Intensity maximum in the middle of the spread angle range, deflection of the pulsed laser light strips in the horizontal beam angle range by pivoting a deflection mirror around a vertical axis, and emission of the pulsed laser light strips in such a way that the intensity maximum lies essentially in a horizontal plane, the method having an additional step for Move the

Intensity distribution of the pulsed laser light strips so that their intensity maximum is shifted from the center of the spread angle range.

The basic idea of the present invention is therefore the use of pulsed laser light strips to detect a field of view of a LiDAR-based

To optimize the environmental sensor so that the asymmetrical

Intensity distribution is shifted along the length of the pulsed laser light strip. The spread angle range can thus experience a different orientation overall than in the prior art, since the intensity maximum continues to be in the horizontal plane, but not the center of the spread angle range, which has the intensity maximum without the shift. This reduces distortion of the laser light beams, which in particular leads to a reduction in the smiley effect. The spread angle range can be pivoted upwards out of the horizontal plane as a whole, which simplifies the design of the laser emitting device. The

The laser emitting device can thus be designed to be compact. A deflection of the emitted pulsed laser light strips in the vertical direction can therefore be dispensed with or reduced in strength.

It is also possible that the spread angle range is reduced overall compared to the prior art. In the prior art, for example, an angular range of 13 ° from the horizontal direction was covered with the laser emitting device, which is usually considered to be sufficient to cover an area above the horizontal direction. When moving the

Intensity maximum remains beyond the angular range of 13 °

Angular range that does not provide any relevant information and is therefore already not used today. The spread of the pulsed laser beams can thus be reduced by this remaining angular range, so that the intensity of the pulsed Laser beams are distributed over a shorter length of the pulsed laser light strips. This allows the detection range of the LiDAR-based environment sensor to be increased.

In a typical laser emitting device, the pulsed laser light strips are emitted obliquely upwards, so that the intensity maximum in

opposite direction, i.e. must be moved down into the horizontal plane. When the laser emitting device is mounted in reverse, for example when mounted on the vehicle roof or in an upper area of a windshield, the pulsed laser light strips are emitted obliquely downwards. In this case the intensity maximum must be in the opposite direction, i.e. upwards, in the horizontal plane.

The vertical shift of the intensity maximum results in a

asymmetrical intensity distribution over the length of the pulsed laser light strips based on a center of the spread angle range.

The information horizontal and vertical are based on a mounted state of the laser emitting device, in particular in a mounted state on the vehicle. Florizontal refers to a plane parallel to a floor plane in the area of the vehicle.

The laser emitting device is used in the LiDAR-based environment sensor in order to cover a detection area defined by the length of the pulsed laser light strips and the horizontal radiation angle range, which is also referred to as the field of view (FoV). Reflections of the pulsed laser light strips on objects in the vicinity are received by the receiving unit of the LiDAR-based environment sensor. Distances to the objects can be determined based on a transit time from the emission of the pulsed laser light strips to the reception of the respective reflections according to the Time of Flight (ToF) principle.

The LiDAR-based environment sensor is designed for use in a vehicle. The LiDAR-based environment sensor is therefore designed to be as compact as possible overall. The LiDAR-based environmental sensor typically delivers Sensor information with the distances to the objects in the vicinity and their position in the detection area to a driving support system of the vehicle. The vehicle can in principle be any vehicle. The vehicle is preferably designed for partially autonomous or autonomous driving.

The laser light source generates the pulsed laser beams. The laser light source is preferably designed to generate pulsed laser beams which are harmless to humans, i.e. as a so-called class 1 laser.

The laser beam spreading unit generates pulsed laser light strips from the pulsed laser beams. For this purpose, the pulsed laser beams are spread in a vertical direction. The pulsed laser light strips have a predetermined

Spread angle range, which indicates a divergence of the pulsed laser light strips.

As a result of the spreading, the pulsed laser light strips have an uneven intensity distribution over their length, with an intensity maximum being present in the middle of the spreading angle range. Accordingly, the pulsed laser light strips have the maximum intensity in their central position. Typically, the intensity drops from the intensity maximum on both sides of the spread angle range or the pulsed laser light strips. The spreading angle range is not to be understood as an absolute angle specification, but merely indicates a dimension and a direction for the spreading. The laser beam spreading unit is designed, for example, as a so-called FAC lens (Fast Axis Collimator).

The deflection mirror causes the pulsed laser light strips to be deflected in the horizontal radiation angle range. For this purpose, the deflecting mirror is designed to be pivotable about a vertical axis. The deflecting mirror is preferably designed as a so-called MEMS mirror using microsystem technology. The deflecting mirror is preferably arranged within a hemispherical dome.

The laser emitting device generates the pulsed laser light strips with a

Intensity distribution whose intensity maximum comes from the center of the

Spreading angle range and thus shifted vertically from its central position. The laser emitting device is further designed to emit the pulsed laser light strips in such a way that the intensity maximum lies essentially in a horizontal plane. The alignment of the spreading angle range when the pulsed Laser light stripes are therefore only selected as a function of the position of the intensity maximum within the spread angle range.

In an advantageous embodiment of the invention, the laser emitting device has a shaped element for shaping the pulsed laser light strips, the shaped element being arranged in a light path of the pulsed laser light strips, in particular between the laser beam spreading unit and the deflecting mirror, and the

The shaped element is designed and / or arranged to shape the intensity distribution of the pulsed laser light strips in such a way that the intensity maximum of the emitted laser light strips is shifted vertically from the center of the spread angle range. The shaped element can be supplemented as an additional element in basically existing laser emitting devices in order to adapt the intensity distribution of the laser light strip in a desired manner and that

To move the intensity maximum vertically. A completely new development of such laser emitting devices or such LiDAR-based environmental sensors can therefore be avoided.

In an advantageous embodiment of the invention, the laser emitting device has a collimator element for collimating the pulsed laser light strips, the collimator element being arranged in a light path of the pulsed laser light strips between the laser beam spreading unit and the deflecting mirror, and that

The collimator element is designed and / or arranged in such a way that the intensity distribution of the pulsed laser light strips is shaped in such a way that the intensity maximum of the emitted laser light strips is shifted vertically from the center of the spread angle range. A combined optical element is thus provided which, on the one hand, collimates the pulsed laser light strip and, on the other hand, that

Shifting the intensity maximum of the emitted laser light strips from the center of the spread angle range in the vertical direction. Thus, the number of optical elements of the laser emitting device compared to current

Laser emitting devices are kept constant, whereby the

Laser emitting device and accordingly the LiDAR-based environment sensor can be provided with compact dimensions. The collimator element serves in particular to collimate the pulsed laser light strips in width and / or in fleas, ie in a horizontal direction as well as in a vertical direction In an advantageous embodiment of the invention, the collimator element for collimating the pulsed laser light strips is designed as a collimator mirror. Corresponding collimator mirrors are known as such and are preferably used here in order to reverse the light path and thus limit a corresponding one

Overall length of the laser emitting device as well as the LiDAR-based one

To effect environmental sensor. This enables a compact

Laser emitting device as well as a compact LiDAR-based environment sensor can be provided. The use of the collimator mirror is well suited for collimating laser light strips. The collimator mirror can be designed, for example, in the manner of an SAC (slow axis collimator).

In an advantageous embodiment of the invention, the collimator element has a decentralized arrangement based on the light path of the pulsed laser light strips and the intensity distribution of the pulsed laser light strips is shaped such that the maximum intensity of the emitted laser light strips comes from the center of the

Spread angle is shifted vertically. The shaping of the intensity distribution of the pulsed laser light strips with the shift of the intensity maximum from the center of the spread angle range can thus be achieved using only components that are customary and used today. Only a modified assembly of the collimator element is required, whereby the

Laser emitting device can be provided particularly inexpensively.

For example, the collimator element can be twisted in the vertical direction compared to an arrangement in the prior art in which the intensity maximum is in the center of the spread angle range.

In an advantageous embodiment of the invention, the laser emitting device has a beam adjuster which is designed in this way and in the light path of the pulsed

Laser light strips is arranged between the laser beam spreading unit and the collimator element in order to shape the intensity distribution of the pulsed laser light strips in such a way that the maximum intensity of the emitted laser light strips is shifted vertically from the center of the spread angle range. Such a beam shifter is known, for example, as a so-called “beam shifter”. Using the

Beam adjuster makes it possible, for example, that the arrangement of collimators in known laser emission devices does not have to be changed in order to achieve a desired change in the intensity distribution of the pulsed laser light strips cause. Further changes to known laser emitting devices are not required in order to remove the maximum intensity from the center of the

To move the spreading angle range vertically. It is only necessary to adapt these known laser emitting devices with the beam adjuster in order to provide a laser emitting device according to the invention. As a result, it is not necessary to completely redesign the known laser emitting devices in order to provide a laser emitting device according to the invention. The beam adjuster is an optical component which is known as such and is not explained further.

In an advantageous embodiment of the invention, the laser beam spreading unit is designed to spread the pulsed laser beams into pulsed laser light strips with a predetermined spread angle range in the vertical direction of less than 45 °, preferably less than 30 °, particularly preferably about 26 °. A larger spreading allows in principle a coverage of a larger vertical angular range and thus a larger field of vision. However, this is accompanied by a decrease in the intensity of the laser light strip, which means that the LiDAR-based environment sensor loses its range.

In an advantageous embodiment of the invention, the laser emitting device is designed to shape the intensity distribution of the pulsed laser light strips in such a way that the intensity maximum of the emitted laser light strips comes from the center of the

Spread angle range by at least a quarter, preferably half the angular range between the center of the spread angle range and one

corresponding edge of the spreading angle range is shifted vertically. The greater the shift, the less it is necessary to deflect the pulsed laser light strips in order to position the intensity maximum in the horizontal plane.

In an advantageous embodiment of the invention, the laser light source is designed as a laser diode rod with a plurality of laser diodes which are arranged in a vertical line to generate a field with a plurality of pulsed laser beams, and the laser beam spreading unit spreads the pulsed laser beams of the field with the plurality of pulsed laser beams together vertical direction to the pulsed laser light strips. The laser diode rod provides the plurality of pulsed laser beams essentially in parallel and synchronously. The individual laser diodes are preferably arranged as close to one another as possible in order to initially have a compact Provide laser beam. The laser beam spreading unit then forms the laser light strip therefrom, which additionally has an improved homogeneity compared to the parallel pulsed laser beams. Individuals of the parallel laser beams can preferably not be seen in the laser light strip. The type of laser light strip is therefore basically identical for the use of laser light sources with a laser diode or with several laser diodes which are arranged together according to the type of laser diode rod. The further refinements of the laser emitting device relate only to the laser light strip, which is why there are no differences depending on the use of laser light sources with a laser diode or with several laser diodes according to the type of laser diode rod.

In an advantageous embodiment of the invention, the laser emitting device has an optical emitting element which deflects the pulsed laser light strips in the vertical direction so that the pulsed laser light strips are emitted in such a way that the maximum intensity is essentially in the horizontal plane. The optical radiating element is typically designed as a prism. The optical emitting element makes it possible to generate the pulsed laser light strips aligned obliquely in order to deflect them later in the direction of the horizontal plane. This enables a simple, compact design of the laser emitting unit. Compared to a laser emitting device from the prior art, the optical

Radiating element be reduced in size, since only a slight deflection of the pulsed laser light strips in the vertical direction is required to achieve the

Deflect intensity maximum in the horizontal plane.

The invention is explained in more detail below with reference to the attached drawing using preferred embodiments. The features shown can represent an aspect of the invention both individually and in combination. Features of various exemplary embodiments can be transferred from one exemplary embodiment to another.

It shows Fig. 1 is a schematic representation of a laser emitting device

LiDAR-based environmental sensor with a deflection mirror that can be swiveled around a vertical axis,

2 shows a schematic representation of a vehicle with the

Laser emitting device from FIG. 1 with emitted, pulsed

Laser light strips which have a symmetrical intensity distribution over the spreading angle range in relation to their center, the intensity maximum being in the horizontal plane,

3 shows a detailed curve of the intensity distribution of the emitted

pulsed laser light strips according to FIG. 2 over the

Spread angle range of the laser light strips,

4 shows a perspective illustration of a laser emitting device of a

LiDAR-based environmental sensor with a laser light source, a laser beam spreading unit, a collimator mirror, a deflecting mirror, and an optical radiating element,

5 shows a schematic representation of a vehicle with the

Laser emitting device from FIG. 2 with emitted, pulsed

Laser light strips which have an asymmetrical intensity distribution over the spreading angle range in relation to one of their centers, the intensity maximum of the pulsed laser light strips lying in the horizontal plane, and

6 shows a detailed curve of the intensity distribution of the emitted

pulsed laser light strips according to FIG. 5 over the

Spread angle range of the laser light strips.

FIG. 4 shows a laser emitting device 30 according to a first preferred one

Embodiment. The laser emitting device 30 is not unique to one

LiDAR-based environmental sensor shown for use in a vehicle

32, which is shown in Figure 5, executed. The laser emitting device 30 comprises a laser light source 34 for generating pulsed laser beams 36. The laser light source 34 is preferably designed to generate pulsed laser beams 36 which are harmless to humans, ie as a

so-called class 1 laser. The laser light source 34 is designed as a laser diode rod with a plurality of laser diodes which are arranged in a vertical line to generate a field with a plurality of pulsed laser beams 36. The laser diode rod provides the plurality of pulsed laser beams 36 which are im

Radiated essentially in parallel and synchronously. The individual laser diodes are preferably arranged as close to one another as possible in order to use the

Laser beams 36 first to form a compact laser beam. The laser diodes are not shown individually in FIG.

The laser emitting device 30 further comprises a laser beam spreading unit 38 which spreads the pulsed laser beams 36 to form pulsed laser light strips 40 with a predetermined spreading angle range a in the vertical direction. Of the

Spread angle range a is not to be understood as an absolute angle specification, but merely indicates a dimension and a direction for the spread. The

In this exemplary embodiment, the laser beam spreading unit 38 is designed as a so-called FAC lens (Fast Axis Collimator). In the case of the one shown in FIG

Laser emitting device 30, the laser light strips 40 have, for example, a spread angle range a of 26 °. In accordance with the vertical

The spreading direction thus defines the spreading angle range a in FIG

The illustrated vertical field of view 42 of the LiDAR-based environment sensor, which is covered by the laser emitting device 30 with the laser light strips 40. In FIG. 5, the vertical field of view 42 is indicated with an angular range from + β ° to -β ° based on a central region o °.

The spread angle range a indicates a divergence of the pulsed laser light strips 40. As shown in particular in FIG. 6, the following results for the pulsed

Laser light strips 40 by spreading an intensity 44 with an uneven intensity distribution over its length 46 with an intensity maximum 48 in the middle of the spread angle range a. This is shown in FIGS. 5 and 6 by the

continuous curve shown. The intensity 44 falls from the intensity maximum 48 symmetrically on both sides of the spread angle range a. The length 46 is here to be understood as a relative indication, since the pulsed laser light strips 40 with

have a greater length 46 as the distance from the laser beam spreading unit 38 increases.

The laser emitting device 30 also comprises a collimator element 50 for collimating the pulsed laser light strips 40. The collimator element 50 is used here initially to collimate the pulsed laser light strips 40 in width and / or height, i.e. in a horizontal direction or in a vertical direction. By doing

In the present exemplary embodiment, the collimator element 50 for collimating the pulsed laser light strips 40 is designed as a collimator mirror on which the light path is reversed. In the present case, the collimator mirror 38 is designed in the manner of an SAC (Slow Axis Collimator).

The laser emitting device 30 also comprises a deflection mirror 52, which is designed to be pivotable about a vertical axis in order to deflect the pulsed laser light strips 40 in a horizontal direction, whereby a horizontal direction

Radiation angle range of the laser emitting device 30 results. The deflection mirror 52 is embodied here as a so-called MEMS mirror using microsystem technology. The deflection mirror 52 is further preferably arranged within a hemispherical dome 54. Another reversal of the light path of the pulsed laser light strips 40 takes place at the deflecting mirror 52.

In the present embodiment, the laser emitting device 30 has an optical emitting element 56 which deflects the pulsed laser light strips 40 in the vertical direction. The optical radiating element 56 is designed here as a prism. The optical emitting element 56 enables the pulsed

To produce laser light strips 30 in the laser emitting device 30 initially aligned obliquely in order to deflect them later with the optical emitting element 56 in the direction of a horizontal plane.

The laser emitting device 30 is designed, the pulsed laser light strips 40 with an intensity distribution whose intensity maximum 48 from the center of the

Spread angle range a is shifted vertically to radiate. The middle of the

Spread angle range a is defined by a central range o ° shown in FIG. For this purpose, the collimator mirror 50 has a decentralized arrangement the light path of the pulsed laser light strips 40. The result is an intensity distribution of the pulsed laser light strips 40, which is shaped overall. The intensity distribution is shaped in such a way that the intensity maximum 48 of the emitted

Laser light strip 40 is displaced vertically from the center of the spreading angle range a, as shown for example in FIGS. 5 and 6. A shift 58 of the intensity maximum 48 is shown there, the shaped intensity 44 with the corresponding intensity maximum 48 being shown by the dashed curve.

The vertical displacement of the intensity maximum 48 results in an asymmetrical intensity distribution over the length 46 of the pulsed laser light strips 40 in relation to the center of the spread angle range a. As can also be seen from FIGS. 5 and 6, the intensity distribution of the pulsed laser light strips 40 is shaped in such a way that the intensity maximum 48 of the emitted laser light strips 40 from the center of the spread angle range a by more than half the angular range between the middle of the spread angle range a and a corresponding edge of the spread angle range a is shifted vertically.

In order to shape the intensity distribution, only a modified assembly of the collimator mirror 50 is required compared to a laser emitting device 30 from the prior art. For example, the collimator mirror 50 can rotate in the vertical direction compared to an arrangement in the prior art, in which the

Intensity maximum 48 lies in the middle of the spread angle range a.

The collimator element 50 is thus provided as a combined optical element which, on the one hand, causes the collimation of the pulsed laser light strip 40 and, on the other hand, the displacement of the intensity maximum 48 of the emitted laser light strips 40 from the center of the spread angle range a in the vertical direction.

As shown in Figure 5, the spread angle range a can thus have an overall orientation upwards, i.e. the central area 0 ° is pivoted from the horizontal, but the pulsed laser light strips 30 are nevertheless emitted in such a way that the intensity maximum 48 lies essentially in the horizontal plane. The shift of the intensity maximum 48 in the horizontal plane is in the embodiment shown by the vertical shift of the

Spread angle range a through the optical emitting element 56 together with the Shifting of the intensity maximum 48 in the vertical direction caused by the collimator element 50. In an alternative embodiment, the laser emitting device 30 does not include an optical emitting element 56, so that the

Displacement of the intensity maximum 48 in the horizontal plane is brought about solely by the displacement of the intensity maximum 48 in the vertical direction by the collimator element 50.

Overall, the laser emitting device 30 becomes a two-dimensional one

Emission area covered, which results from the alignment and length 46 of the vertical pulsed laser light strips 40 and the movement of the deflection mirror 52 about the vertical axis in the horizontal emission angle range.

In an alternative embodiment not shown here, the

Laser emitting device 30 has a beam adjuster which is designed and arranged in the light path of the pulsed laser light stripes 40 between the laser beam spreading unit 38 and the collimator element 50 in order to shape the intensity distribution of the pulsed laser light stripes 40 in such a way that the intensity maximum 48 of the emitted laser light stripes 40 from the center of the spread angle range a is shifted vertically. Such a beam shifter is known, for example, as a so-called “beam shifter”.

The LiDAR-based environment sensor is designed in particular for use in the vehicle 32. The laser emitting device 30 is used in the LiDAR-based environment sensor in order to cover a detection area defined by the length 46 and alignment of the pulsed laser light strips 40 and the horizontal emission angle range, which is also referred to as the field of view (FoV) and corresponds to the emission area .

The LiDAR-based environmental sensor includes in addition to the above

Laser emitting device 30 a receiving unit, not shown here, for receiving reflections of the pulsed laser light strips 40 emitted by the laser emitting device 30 in the emission area. The LiDAR-based environment sensor typically supplies sensor information with distances to objects in a

Surroundings of the vehicle 32 and their position in a detection area to a driving support system of the vehicle 32. The distances to the objects can can be determined based on a transit time from the emission of the pulsed laser light strips 40 to the reception of the respective reflections according to the time of flight (ToF) principle.

The vehicle 32 can in principle be any vehicle 32. The vehicle 32 is preferably designed for partially autonomous or autonomous driving.

In the above description, the information is horizontal and vertical based on a mounted state of the laser emitting device 30, in particular in a mounted state on the vehicle 32. Horizontal here refers to a plane parallel to a floor plane in the area of the vehicle 32.

List of reference symbols

10 Laser emitting device (state of the art)

12 Laser beam spreading unit (state of the art)

14 laser light strips (state of the art)

16 deflection mirrors (state of the art)

18 vertical axis (state of technology)

20 vehicle (state of the art)

22 Intensity (state of technology)

24 vertical field of view (state of the art)

26 intensity maximum (state of the art)

30 laser emitting device

32 vehicle

34 Laser light source

36 laser beam

38 Laser beam spreading unit

40 laser light strips

42 vertical field of view

44 intensity

46 length

48 intensity maximum

50 collimator element, collimator mirror

52 deflection mirror

54 Cathedral

56 optical radiating element

58 Shift a spread angle range

+ ß ° / -ß ° angle range

o ° middle area

Claims

1. Laser emitting device (30) for emitting pulsed laser light strips in a horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle (32), comprising a laser light source (34) for generating pulsed laser beams (36), a laser beam spreading unit ( 38), which the pulsed laser beams (36) to pulsed laser light strips (40) with a predetermined

Spread angle range (a) spreads in the vertical direction, the pulsed laser light strips (40) having an uneven intensity distribution over their length (46) with an intensity maximum (48) in the middle of the

Spread angle range (a), and

a deflection mirror (52) which is designed to be pivotable about a vertical axis in order to deflect the pulsed laser light strips (40) in the horizontal radiation angle range, wherein

the laser emitting device (30) is designed to be pulsed

To emit laser light strips (40) in such a way that the intensity maximum (48) lies essentially in a horizontal plane,

characterized in that

the laser emitting device (30) is designed to be pulsed

Laser light strips (40) with an intensity distribution, the intensity maximum (48) of which is displaced vertically from the center of the spread angle range (a).

2. Laser emitting device (30) according to claim 1, characterized in that the laser emitting device (30) has a molding element for shaping the pulsed laser light strips (40), wherein

the shaped element in a light path of the pulsed laser light strips (40), in particular between the laser beam spreading unit (38) and the

Deflection mirror (52), is arranged, and

the shaped element is designed and / or arranged to shape the intensity distribution of the pulsed laser light strips (40) such that the intensity maximum (48) of the emitted laser light strips (40) is shifted vertically from the center of the spread angle range (a).

3. Laser emitting device (30) according to one of the preceding claims 1 or 2, characterized in that

the laser emitting device (30) has a collimator element (50) for collimating the pulsed laser light strips (40), wherein

the collimator element (50) in a light path of the pulsed

Laser light strip (40) is arranged between the laser beam spreading unit (38) and the deflecting mirror (52), and

the collimator element (50) is designed and / or arranged to shape the intensity distribution of the pulsed laser light strips (40) in such a way that the intensity maximum (48) of the emitted laser light strips (40) is shifted vertically from the center of the spread angle range (a).

4. Laser emitting device (30) according to claim 3, characterized in that the collimator element (50) for collimating the pulsed laser light strips (40) is designed as a collimator mirror (50).

5. Laser emitting device (30) according to one of the preceding claims 3 or 4, characterized in that

the collimator element (50) has a decentralized arrangement with respect to the light path of the pulsed laser light strips (40) and the

The intensity distribution of the pulsed laser light strips (40) is shaped in such a way that the intensity maximum (48) of the emitted laser light strips (40) is shifted vertically from the center of the spread angle range (a).

6. Laser emitting device (30) according to one of the preceding claims 3 or 4, characterized in that

the laser emitting device (30) has a beam adjuster which is designed and arranged in the light path of the pulsed laser light strips (40) between the laser beam spreading unit (38) and the collimator element (50) in order to adjust the intensity distribution of the pulsed laser light strips (40) shape so that the intensity maximum (48) of the emitted laser light strips (40) is shifted vertically from the center of the spread angle range (a).

7. Laser emitting device (30) according to one of the preceding claims,

characterized in that

the laser beam spreading unit (38) is designed to transform the pulsed laser beams (36) into pulsed laser light strips (40) with a predetermined spreading angle range (a) in the vertical direction of less than 45 °,

preferably less than 30 °, particularly preferably about 26 °.

8. Laser emitting device (30) according to one of the preceding claims,

characterized in that

the laser emitting device (30) is designed to shape the intensity distribution of the pulsed laser light strips (40) such that the intensity maximum (48) of the emitted laser light strips (40) from the center of the

Spread angle range (a) is shifted vertically by at least a quarter, preferably half, of the angular range between the center of the spread angle range (a) and a corresponding edge of the spread angle range (a).

9. Laser emitting device (30) according to one of the preceding claims,

characterized in that

the laser light source (32) is designed as a laser diode rod with a plurality of laser diodes which are arranged in a vertical line for generating a field with a plurality of pulsed laser beams (36), and

the laser beam spreading unit (38) spreads the pulsed laser beams (36) of the field with a plurality of pulsed laser beams (36) together in the vertical direction to the pulsed laser light strips (40).

10. Laser emitting device (30) according to one of the preceding claims,

characterized in that

the laser emitting device (30) has an optical emitting element (56) which deflects the pulsed laser light strips (40) in the vertical direction so that the pulsed laser light strips (40) are emitted in such a way that that the intensity maximum (48) lies essentially in a horizontal plane.

1 1. LiDAR-based environment sensor, especially for use in a

Vehicle (32), with

a laser emitting device (30) according to one of the preceding claims, and

a receiving unit for receiving reflections of the pulsed laser light strips (40) emitted by the laser emitting device (30) in the emitting area.

12. A method for emitting pulsed laser light strips (40) in one

Horizontal radiation angle range, in particular for a LiDAR-based environment sensor for use in a vehicle (32), comprising the steps

Generation of pulsed laser beams (36),

Spreading the pulsed laser beams (36) to form pulsed laser light strips (40) with a predetermined spread angle range (a) in the vertical direction, the pulsed laser light strips (40) having a non-uniform

Intensity distribution over its length (46) have with a

Intensity maximum (48) in the middle of the spread angle range (a),

Deflecting the pulsed laser light strips (40) in the horizontal radiation angle range by pivoting a deflecting mirror (34) about a vertical axis (38), and

Radiation of the pulsed laser light strips (40) in such a way that the intensity maximum (48) lies essentially in a horizontal plane,

characterized in that

the method has an additional step for shifting the intensity distribution of the pulsed laser light strips (40) so that their

Intensity maximum (48) is shifted vertically from the center of the spreading angle range (a).