WO2019110206A1

WO2019110206A1 - Lidar system for surroundings detection and method for operating a lidar system

Info

Publication number: WO2019110206A1
Application number: PCT/EP2018/079825
Authority: WO
Inventors: Andre Nauen
Original assignee: Osram Gmbh
Priority date: 2017-12-04
Filing date: 2018-10-31
Publication date: 2019-06-13
Also published as: DE102017221797A1

Abstract

The invention relates to a LIDAR system (10) for surroundings detection which is designed to repeatedly carry out measurements in order to detect the surroundings, wherein the lidar system (10) has an emission unit (12) which is designed to emit at least one light beam in order to carry out a measurement, wherein the lidar system (10) has a detection unit (14) which is designed to detect a beam portion reflected during a measurement, wherein the lidar system (10) has a control device (16) which is designed to associate, if at least one reflected beam portion is detected, a solid angle range (Ω1, Ω2, Ω3) with the detected beam portion on the basis of a predetermined association (ZI). Furthermore, the lidar system (10) has at least one movable component (18, 22, 28, 20, 32, 34) and an actuator which is designed to move the components (18, 22, 28, 20, 32, 34) from a first position (PI) into at least one second position (P2) which is different from the first position (P1), wherein, if the components (18, 22, 28, 20, 32, 34) are situated in the second position (P2), the association (Z2) is modified in a predetermined way.

Description

LIDAR SYSTEM FOR AMPLIFICATION AND METHOD FOR OPERATING

A LIDAR SYSTEM

DESCRIPTION

The invention relates to a LIDAR system for environment detection, wherein the LIDAR system is designed to carry out repeated measurements for detecting the environment, the LIDAR system having a transmitting unit which is designed to emit at least one light beam for carrying out a measurement and wherein the LIDAR system has a

Detection unit which is designed to detect a reflected during a measurement steel content.

Furthermore, the LIDAR system has a control device which is designed in the event that at least one

reflected beam component is detected, the detected

Beam component based on a predetermined assignment to allocate a solid angle range, from which the beam component comes. The invention also includes a method for operating a LIDAR system.

The function of a LIDAR system is based on a

Transit time measurement of emitted light signals. When these impinge on surfaces in the vicinity of the LIDAR system, some of the emitted power is reflected towards the LIDAR system. Accordingly, the pulse echo can be recorded with a suitable detector. If the transmission of the pulse takes place at a first time and the echo signal is detected at a later second time, then the distance to the reflecting surface over the transit time, which represents the difference between the first and the second time, can be calculated. A LIDAR system usually works with light pulses that have a specific

Wavelength, for example, 905 nanometers, and have a certain pulse length. Furthermore, every light pulse

typically associated with a measurement time window which begins with the emission of the measurement light pulse. In LIDAR systems also differently designed transmitters and receiver concepts are known to the

To be able to record distance information in different spatial directions. Based on this, a two-dimensional image of the environment is then generated, which contains the complete three-dimensional coordinates for each resolved spatial point. The different LIDAR topologies can be abstracted based on the way the image resolution is displayed. Namely, the resolution can be represented either exclusively by an angle-sensitive detector, an angle-sensitive emitter, or a combination of both. A LIDAR system, which generates its resolution exclusively by means of the detector, is called a Flash LIDAR. It consists of an emitter, which illuminates as homogeneously as possible the entire field of vision. The detector on the other hand consists in this case of several individually readable and arranged in a matrix segments or pixels. Each of these pixels is accordingly one

Solid angle range assigned. If light is received in a certain pixel, then the light correspondingly comes from the solid angle range assigned to this pixel. In contrast to this, a raster LIDAR has an emitter which emits the measuring pulses selectively and in particular temporally sequentially in different spatial directions. As a detector sufficient here is a single segment. If, in this case, light is received by the detector in a certain measuring time window, then this light originates from a solid angle range into which the light was emitted by the emitter in the same measuring time window.

In this context, DE 10 2015 101 902 A1 describes a detector and a LIDAR system, wherein the detector has a series of juxtaposed radiation-sensitive pixels. The pixels of the row have such contours that opposite sides of adjacent pixels are at least partially different from a vertical one

Direction extend to a direction of extension of the series. By such a geometrical interpretation of the pixels should Dead zones due to the pixels separating

radiation-insensitive intermediate areas are avoided. But even with such a geometric configuration of the individual pixels, radiation-insensitive areas between the pixels can not be avoided. Along with this, gaps in the detectable field of view can not be avoided.

Also desirable in LIDAR systems is always an increase in resolution. Most of the time, however, this can only be accomplished by larger image sensors with more pixels, which is very expensive and requires additional space.

The object of the present invention is therefore to provide a LIDAR system and a method for operating a LIDAR system, which enable a more effective detection of a field of view.

This object is achieved by a LIDAR system and a method for operating a LIDAR system having the features according to the respective independent claims. Advantageous embodiments of the invention can be found in the dependent claims, the description and the figures.

An inventive LIDAR system for environment detection is designed to repeat the detection of the environment

Perform measurements. In this case, the LIDAR system has a transmitting unit which is designed for the

Performing a measurement emit at least one light beam, wherein the LIDAR system comprises a detection unit which is adapted to detect a reflected during a measurement steel content. In addition, the LIDAR system has a control device that

is designed, in the case that at least one reflected beam component is detected to assign the detected beam component based on a predetermined assignment a solid angle range from which the beam component comes. In addition, the LIDAR system has at least one movable Component and an actuator which is adapted to move the component from a first position to a second position different from the first position, wherein, when the component is in the second position, the assignment is changed in a predetermined manner.

The movable component may, for example, a

Represent detector matrix. So for example, the

Detector matrix shifted by half a pixel width, so can by suitable evaluation of these two in the

be generated at different positions of the detector sub-images recorded image with higher resolution. However, the same effect can also be achieved, if not the detector matrix, but other components of the LIDAR system, for example a detector optics relative to the detector or also an emitter matrix, as will be described in more detail later

be explained, be moved. In principle, it is thus advantageously possible, by shifting a LIDAR component, to increase the resolution of the LIDAR system, without any components of the LIDAR system, such as the detector

or have to train the image sensor larger. By shifting a LIDAR component, it is also possible to accomplish gaps in the field of view that occur in a measurement when this is moving

Component is in the first position to capture by moving this component to the second position.

Overall, this can be a much more effective

Capture the field of view of the LIDAR system.

In an advantageous embodiment of the invention, the LIDAR system is adapted to a first measurement

perform, in which the movable component is in the first position, and at least perform a second measurement in which the movable

Component is located in the second position, the

Control device is designed to combine the first measurement and the at least one second measurement and on Basis of the combination to provide a spatially resolved measurement result, which has a resolution that is higher than a provided on the basis of only the first or only the second measurement provided spatially resolved measurement result.

By combining the in these two positions the

In the end, measurements of moving components can be used to generate an image of the environment, which has a much higher resolution than the respective partial images provided in the individual measurements. In particular, depending on the situation, the resolution can possibly even be doubled.

For example, the movable component may form part of the detection unit. It is preferred if the detection unit has a detector with several pixels, wherein the detector represents the movable component. The detector may thus be provided as an image sensor with a plurality of pixels suitable for a particular one

Wavelength range is sensitive. Such an image sensor usually represents a particularly light component, so that the detector is particularly easy to move, which ultimately also a shift of

Detector can be implemented in a particularly efficient simple and, above all, fast way.

In particular, when the detector is in the first position, each of the pixels is a respective one

predetermined first spatial angle range, wherein, when the detector is in the second position, each of the pixels is associated with a respective second solid angle range, wherein a respective second

Solid angle range at least partially different from a respective first solid angle range, and preferably overlaps with a respective first solid angle range. By a displacement of the detector, on the one hand, it can thus advantageously be achieved that in the second position solid angle ranges are covered, which were previously detected in FIG the first position of the detector were not covered. It is particularly advantageous if the two

Solid angle ranges nevertheless with the respective first

At least partially overlap solid angle ranges, so that due to this overlap by comparing two consecutive measurements in which the detector has been in different positions,

Additional information can be obtained, which

Resolution increase can be used.

In a further advantageous embodiment of the invention, the pixels of the detector are in at least a first

In a row, wherein a respective pixel in the first direction has a width, and wherein the detector is shifted in the second position from the first position in the first direction by less than a width of a pixel. By such

Shift, the field of view detected by the LIDAR system does not substantially change. The change in the field of view is therefore at most as large as the spatial angle range detectable by a pixel with respect to the first direction. By this configuration is therefore only a particularly small

Displacement of the movable component or the detector required to those described above

Resolution increase as well as the more effective capture of the

Field of view of the LIDAR system.

It has proven to be particularly advantageous if the detector is in the second position relative to the first

Position is shifted by half the width of the pixel in the row. In the width of a pixel is also an optionally existing between two pixels

Be considered intermediate area. In other words, the width of a pixel is defined as the distance between the centers of two consecutive pixels in the first direction. Thus, for example, if a first pixel and subsequently a second pixel are arranged in a row in the first direction, then in the first position of the Detector the first pixel a first solid angle range and the second pixel a second solid angle range. In the second position, these pixels are shifted in such a way that now the new position of the first pixel is shifted relative to its original position by half its width or the distance between the centers of the first and second pixels in the direction of the second pixel. Accordingly, in this new second position, this first pixel now detects half of the solid angle range detected by the first pixel in the first position, and approximately half of that of the second pixel in its first position

Position detected solid angle range. Such a shift can increase the resolution

maximize. In this way, a pixel in the second position is shifted exactly in the middle between two pixels with respect to the first position, which enables a particularly efficient detection of the field of view of the LIDAR system.

In a further advantageous embodiment of the invention, the pixels of the detector are in turn arranged in at least a first direction in a row, wherein a

respective pixel in the first direction has a width and in a second direction which is perpendicular to the first direction, a length and in a third direction extending between the first and second direction a third

Diagonal, and wherein the detector in the second position relative to the first position in the third direction

is shifted, in particular by less than a length of the diagonal of a pixel. In this case, the diagonal can be defined analogously to the definition of the width of a pixel, that is to say that the spaces between diagonally arranged pixels are taken into account in the length of the diagonal. In other words, the length of the diagonal of a pixel may be the distance between two

Centers of two diagonally arranged

Be defined pixels. This embodiment has the particularly great advantage that in this way an increase in resolution in two dimensions can be achieved without the detector To be able to move in two different directions. Thus, the displacement of the detector in one direction, the third direction, is sufficient around one

Resolution increase in two dimensions to achieve.

This embodiment is also particularly advantageous if the detector has a plurality of rows of pixels. Again, the detector can be half the length of the

Diagonals of a pixel can be moved from the first to the second position or even more or less. Again, the shift may again be defined by a random length between a minimum length and a maximum length, which may now be defined in relation to the pixel width with respect to the length of the diagonal of a pixel,

is particularly particularly advantageous when

A movement of the detector or in general the

moving component is not just in one

Direction of space possible, but for example in two. Therefore, it is a further advantageous embodiment of the invention, when the actuator is adapted to move the movable component from the first position to the second position in a first direction, and from the first and / or second position to a third position in FIG a second to move from the first different direction, in particular wherein the second direction is perpendicular to the first direction. Thus, for example, if the detector is designed as a two-dimensional pixel matrix, a displacement of the detector both in the direction of the rows and in the direction of the columns of these

done in two-dimensional matrix. Thus, a

Resolution increase as well as a more effective and

Gapless coverage of the field of view of the LIDAR system can be realized in two dimensions.

In a particularly advantageous embodiment of the invention, the control device is adapted to randomly select at least the second position between a minimum position and a maximum position and the actuator for Setting the second position to control. Thus, the moving scheme of the movable component does not necessarily have to be a regular scheme, as described above, according to which the movable component is placed in the one according to a predetermined sequence

different positions, that is, the first position, the second position, possibly the third position or other positions is moved, but this

Movement scheme can also be a stochastic scheme

according to which the spatial position of the movable component is varied randomly, in particular within fixed limits, which are defined by the minimum position and the maximum position. For example, the maximum position may be away from the first position in the first direction by at most half the pixel width as defined above, while the minimum position

for example, in the first direction from the first position is at least one tenth of the width of a pixel away. Displacing the movable component, such as the detector, by less than one-tenth of the pixel size of the detector is not very useful, as this will not result in a very significant increase in resolution. This could be done, for example, by a corresponding rounding or quantization of the random numbers, on the basis of which the second position is randomly determined. The definition of a minimum position

or one of a minimum displacement does not necessarily have to be related to the first position, but may also be related to the last position or current position of the movable component. In other words, a limitation of the minimum shift compared to the previous field can be done. This is for example particularly advantageous in order to avoid clumping of the partial images and thus to achieve a meaningful balance between coverage of the field of view and resolution improvement. In addition, the second position can also be determined by superposition of a temporally regular function with a random value. The advantage of Moving the moveable component to randomly determined positions and resulting randomized generation of subimages is such that aliasing or moire artifacts can be reduced or de facto avoided.

In a further advantageous embodiment of the invention, the detection unit has at least one first optical element, which represents the movable component. Such an optical element may, for example, a the

Detector associated optics, which consist of a

determine field of view of the LIDAR system on these optics incident beams in a predetermined manner on the detector images. So instead of the detector over others

Moving components, for example, the optical element, it is also possible in an analogous manner, to move this first optical element relative to the detector. Here, too, it is advantageous if the movement of the first optical element takes place, for example, in the first direction by a distance which is at most as long as the width of a pixel of the detector. For example, the first optical element may be shifted relative to the detector by half a pixel width in the second position from the first position. Again, a movement of the first optical element in one as well as in two independent directions, which are in particular perpendicular to each other, possible here again. In addition, here too, the movement of the first

follow a regular pattern or, as already described for the detector, follow a stochastic scheme according to which the second position,

Preferably, between a predetermined minimum position and maximum position, which may be defined analogous to the above, is randomly selected and set. Thus, therefore, advantageously with respect to the

Movement of the detector described embodiments in an analogous manner for the movement of the first optical

Component are implemented relative to the detector, whereby the advantages and effects achieved by the same remain the same. The detection unit can not only have a single optical element, but also a plurality of optical elements in a particular arrangement to each other, in turn, an entire arrangement of a plurality of optical

Elements can also represent the movable component. For example, the detection unit can be a

Have secondary optics and a detector optics. The

Secondary optics can be, for example, a lens or, in turn, an optical system composed of several individual optical elements

Represent elements. The secondary optics can do this

Defining the overall view of the LIDAR system. Furthermore, this secondary optics can be designed to have a respective solid angle segment or a specific one

Solid angle range of the LIDAR field of view to a respective pixel of the detector. It defines the field of vision of the LIDAR system across all solid angle segments. The optional additional detector optics can be located between the secondary optics and the detector. In addition, the detector optics can optimize the mapping of the solid angle segments to the individual pixels of the detector. For example, this detector optics can be designed as a microlens array or the like. Accordingly, therefore, for example, the secondary optics or the detector optics can also represent the movable component. However, the preferred

Detector optics and not the secondary optics of the detector designed as a movable component, since the detector optics has a significantly lower weight and thus is much faster movable.

This provides numerous options for increasing the resolution and for more effectively detecting the field of view of the LIDAR system. However, the increase in resolution can not only be accomplished on the detector side, but can also be implemented on the emitter side in an analogous manner. Therefore, it is an advantageous embodiment of the invention, when the movable component is a part of the transmitting unit. This also makes it advantageously possible to increase the resolution and to capture the field of view of the LIDAR sensor more efficient.

For example, the transmitting unit may have an emitter arrangement comprising a plurality of emitter units arranged in at least one row, wherein the

Emitter arrangement represents the movable component. This emitter arrangement can be designed analogously to a detector with a plurality of pixels arranged in a matrix. In other words, such an emitter matrix can also be made

Emitter units be formed with multiple rows and columns. In the simplest case, such an emitter array is provided as a single row of emitter units. This emitter arrangement can now likewise be moved analogously to the detector described, namely preferably in the direction of the at least one row by a length which is at most as great as the width of an emitter unit in this direction. Also, the shift may in turn be done diagonally to the emitter units arranged in one or more rows, for example by half the length of one emitter

Diagonals of an emitter unit. In this case, too, a shift by a length which corresponds to half the width, or also the diagonal, of an emitter unit in a specific direction preferably also takes place here. Theoretically, however, the displacement can also be greater, in particular greater than half the width of an emitter unit and also larger than the entire width of an emitter unit. Again, the shift in both one and in two dimensions, depending on the application and the formation of the emitter arrangement, that is, whether as a single row or as a two-dimensional matrix, take place.

In a further advantageous embodiment of the invention, it is provided that a respective emitter unit in the first position of the emitter arrangement, a respective one associated with the third solid angle range, which is illuminated by the respective emitter unit, wherein a

respective emitter unit in the second position of

Emitter arrangement is assigned a respective one of the respective third solid angle ranges at least partially different fourth solid angle range. If, for example, the transmitting unit is set up in such a way that the respective third solid angle ranges are disjoint, that is, not connected to one another, there are unilluminated solid angle ranges between these third ones

Solid angle ranges, it can be achieved by a displacement of the emitter array that in the second

Position now also these previously not illuminated

Solid angle ranges are illuminated. An overlap with the previously illuminated solid angle ranges is still possible. This, in turn, also makes it possible

Detect the field of vision of the LIDAR system much more efficiently.

Alternatively or additionally, the emitter arrangement does not necessarily have to be moved again, for example relative to an emitter optic, but an optic can also be moved relative to the emitter arrangement, which, however, in turn causes the same effect. Accordingly, it represents a further advantageous embodiment of the invention, when the transmitting unit at least a second optical

Element having which the movable component

represents. This second optical element can again represent a single lens, or it can also be a single lens

Arrangement of a plurality of optical elements may be provided as the movable component. For example, here again, the transmitting unit may have a secondary optic, which is designed to control the light emission of the individual

Emitter units in a predetermined manner suitable in the

Depict far-field. In the case of a pure Flash LIDAR so by means of the secondary optics each in one

arranged two-dimensional matrix emitter unit in an associated solid angle segment or a

mapped solid angle range shown. In addition, the Sending unit optionally also a further emitter optics

which in turn may be arranged between the emitter assembly and the secondary optics. The emitter optic may optionally provide for emitter emission deformation to accommodate secondary optics. To realize the

At the transmitter-side resolution increase, the emitter optics can represent the movable component and can be moved as described in order to be able to displace the irradiated solid angle segments or solid angle ranges. In turn, since the emitter optics can have a significantly lower weight than the secondary optics, it is preferable to design the emitter optics as a movable component, since correspondingly much faster movements are then possible.

Furthermore, the LIDAR system can do this, for example

be formed, the at least one light beam as

Send light pulse. In addition, the light rays

or light pulses are emitted at a wavelength which is preferably in the range between 850 nanometers and 1600 nanometers, or in other areas.

For example, the wavelength of the emitted

Light rays or light pulses at 905 nanometers or 1064 nanometers or 1548 nanometers or 5600

Nanometers or 8100 nanometers. However, other wavelengths are also conceivable, for example less than 850 nanometers, for example 600 nanometers, 650 nanometers, 700 nanometers, 750 nanometers or 800 nanometers. Furthermore, the LIDAR system can be designed to emit light pulses having a frequency between one kilohertz and one megahertz, preferably with a frequency smaller than 100 kilohertz. In addition, the detection range of the LIDAR system can be between a few centimeters, for example 20 centimeters, up to 300 meters, possibly even further. Accordingly, the measurement time window, ie the measurement period from the emission of a light pulse, within which the detector or the individual detector pixels are read out, for example, last two microseconds, which is the duration of a light pulse in Case of reflection on an object 300 meters away. However, the respective measurement time windows do not necessarily always have to remain the same, but can, for example, also be adapted dynamically to the distance of recently detected objects. In addition, the

Time duration for which the movable component is in the first, the second and optional further positions, correlated with the time duration of the respective measuring time window, in particular such that during a respective measuring time window no displacement of the movable

Component takes place. Instead, the shift occurs between two consecutive measurement time windows, but not necessarily after each measurement time window. The individual light pulses can continue to have a pulse length between 1 and 100 nanoseconds. Preferably, the pulse length is in the range of a few nanoseconds, such as 1 nanosecond, 5 nanoseconds, 10

Nanoseconds, 15 nanoseconds, 20 nanoseconds, and so on, but preferably less than 5 nanoseconds. Also, the LIDAR system, for example, as

be designed Flash LIDAR, his

Resolution exclusively generated by means of the detector, which consists in this case of several individually readable segments or pixels. In order to enable a spatial resolution in only one dimension, a single row with readable segments or pixels is sufficient. If a resolution in two dimensions is to be provided, this can be accomplished by a detector having a plurality of individually readable and arranged in a matrix with a plurality of rows and columns segments or pixels. The transmitting unit can in this case only one single emitter arrangement

Have emitter unit. In addition, in this case, the

Resolution increase accomplished by a detector-side movable component. Thus, for example, the detector itself can be moved or also an optics associated with the detector relative to the detector. In addition, the LIDAR system can also be designed as a raster LIDAR, the having an emitter, which the measuring light pulses targeted in different spatial directions or

Solid angle ranges emits, especially in time

sequential, whereby here as a detector also a single segment, that is a single pixel is sufficient. In this case, the detector may be combined with an optic which images the entire field of view of the LIDAR system onto the single pixel element. Furthermore, in this example, the transmitting unit can have an emitter arrangement, which can be used as an or

formed two-dimensional emitter matrix whose parts, that is, the individual emitter units, each can be controlled individually. Advantageous are

Laser light sources which emit in the range between 850 nanometers and 1600 nanometers pulses of power between 30 watts and 200 watts, preferably with a pulse length in the range between 1 nanosecond and 100 nanoseconds. In principle, both strip emitters and VCSEL types, for example VCSEL and VECSEL, can be used

Surface emitter, are used. The light sources can basically be provided both as LEDs and as laser diodes. The individual, by such

Emitter emitted light pulses can have a power in the range of a few milliwatts (VCSEL) and between 30 watts and 200 watts (VECSEL). In the case of a raster LIDAR, it is preferred that the one described above

Resolution increase by an emitter-side moving

Component is realized. For example, as described, either the emitter arrangement relative to an optic or the optics associated with the emitter arrangement can be moved relative to the emitter arrangement.

Also, the LIDAR system may be formed as a hybrid of both LIDAR types, that is, Flash LIDAR and raster LIDAR, for example, such that one in one dimension

Detent movement takes place, the resolution in the second dimension but by means of an angle-sensitive in this dimension

Detector is achieved. In this example, therefore, the emitter or the emitter arrangement as a

one-dimensional matrix can be formed from individual emitters which, optionally by means of a suitable optics, illuminates in a first dimension or direction temporally sequentially a certain solid angle range. The detector may also be formed as a one-dimensional pixel matrix, which has a spatial or angular resolution in the

provide corresponding second dimension by a respective pixel a corresponding solid angle range

assigned. In such a case, the

Resolution increase be realized by a movable component both emitter side and detector side.

For example, in this example, both the detector and the emitter arrangement can be designed to be movable and, for the increase in resolution, be moved from a respective first position into a corresponding second position.

In addition, the LIDAR system or one of its embodiments according to the invention preferably finds application

Motor vehicles. Accordingly, a motor vehicle with a LIDAR system according to the invention or one of his

Embodiments are considered as belonging to the invention. In principle, however, there are no limits to the fields of application of the LIDAR system according to the invention or its embodiments. This can also be used, for example, in aircraft, drones, ships, lighthouses,

pivotable lighting devices in the entertainment and studio lighting area, or the like are used.

Furthermore, the invention also relates to a method for operating a LIDAR system, which performs repeated measurements for environment detection, in which each case

at least one light beam is emitted by the LIDAR system and, in the event that during a measurement at least one reflected steel component is detected, the detected

Beam portion is assigned based on a predetermined assignment a solid angle range, from which the Beam component comes. Furthermore, at least one

movable component of the LIDAR system, in particular

between two respective measurements, from a first position to at least one second position different from the first position, in which the assignment in

is changed in a predetermined manner.

The LIDAR system according to the invention and its

Embodiments mentioned advantages apply in the same way for the inventive method. Furthermore

allow the mentioned in connection with the LIDAR system according to the invention and its embodiments

representational characteristics of the further education of the

inventive method by further

Procedural steps.

Further advantages, features and details of the invention will become apparent from the claims, the following

Description of preferred embodiments, and with reference to the drawing.

Brief description of the drawings

In the following, the invention is based on

Embodiments will be explained in more detail.

Showing:

Fig. 1 is a schematic representation of a LIDAR system according to an embodiment of the invention;

Fig. 2 is a schematic cross-sectional view of a

Detection unit of a LIDAR system according to an embodiment of the invention;

Fig. 3 is a schematic cross-sectional view of a

Detection unit according to another

Embodiment of the invention; Fig. 4 is a schematic representation of a

Detection unit of a LIDAR system in cross section according to another

Embodiment of the invention.

Fig. 5 is a schematic cross-sectional view of a

Transmitting unit according to an embodiment of the invention; and

Fig. 6 is a schematic representation of a transmitting unit of a LIDAR system in cross section according to another embodiment of the invention.

Fig. 1 shows a schematic representation of a LIDAR system 10 according to an embodiment of the invention. The LIDAR system 10 has in this example a transmitting unit 12, a detection unit 14 and a control device 16. The transmitting unit 12 is designed to emit repeated measuring light pulses. If such measuring light pulses on an object in the vicinity of the LIDAR system 10th

reflected, so at least a reflected portion of the detection unit 14 of the LIDAR system 10 can be detected. The LIDAR system 10 may further be configured as a Flash LIDAR, as a raster LIDAR or as a combination of both LIDAR types. In the embodiment as a flash LIDAR, the resolution is generated exclusively by means of the detection unit 14, which in such a case has a detector 18 with a plurality of individually readable and arranged in a matrix segments in the form of pixels 20. Furthermore, a

corresponding optics 25 (see FIG. 3 and FIG. 4)

be provided, which images different solid angle segments or solid angle areas on the individual pixels 20. The LIDAR system 10 may alternatively be referred to as

Raster LIDAR be formed, in which by the

Transmitting unit 12 measuring pulses targeted to different

Spaces or solid angle ranges are emitted, in particular temporally sequential. For this purpose, the Transmitting unit 12, a corresponding emitter array 22 in the form of a one- or two-dimensional emitter matrix

have, in turn, a plurality of individual emitter 24 as separately controllable emitter units. A respective one

Single emitter 24 can then via an appropriate optics 26 (see FIG. 5 and FIG. 6) an associated

Illuminate solid angle range. In the case of a raster LIDAR, a single segment, that is to say a single pixel 20, in particular in combination with a corresponding optical system 25, which images the entire field of view of the LIDAR system 10 onto this individual segment, is sufficient as the detector.

In the example shown in FIG. 1, the LIDAR system 10 is embodied as a hybrid of the LIDAR types mentioned, so that a raster movement takes place in a first dimension D1, that is to say temporally sequential illumination of individual solid angle regions arranged side by side in the first dimension D1 by individual control of the individual emitter 24. The resolution in the second dimension D2 is determined by a in this second dimension D2

angle-selective detector 18 accomplished. Thus, in the second dimension D2 are arranged side by side

Solid angle ranges mapped to respective associated pixels 20 of this detector 18. Thus, every object can

or object point in the vicinity of the LIDAR system 10, which is in the detection range of the LIDAR system 10, a 2D coordinate based on the knowledge of which the single emitter 24 has emitted a light pulse and based on the knowledge of which of the pixels 18

reflected fraction of this light pulse has been determined. The third spatial coordinate, which indicates the distance to the LIDAR system 10, is determined on the basis of the transit time measurement of this emitted and detected light pulse. So to provide a three-dimensional image of the environment, so in this example are a one-dimensional

Emitter matrix 22, as well as a one-dimensional trained detector 18 sufficient. Such a combination of raster and flash LIDAR is also referred to as hybrid raster LIDAR. The detector 18 can generally consist of a one- or two-dimensional arrangement of individual pixels 20, which can each be read out individually.

In principle, any type of detector 18 is contemplated, which is the LIDAR wavelength, typically between 850

Nanometers and 1600 nanometers, with one

Minimum bandwidth, which is typically greater than 1 megahertz, can convert into an electrical voltage. Specifically, these may be, for example, a PIN diode, an avalanche photo diode (APD), a single photon avalanche photo diode (SPAD) or a photomultiplier. In addition, other types of detectors 18 come into question.

The controller 16 is adapted to both the

To control transmitting unit 12 and to make the evaluation of the signals received by the receiving unit 14.

To achieve an increase in resolution, it is now

advantageously provided that at least one LIDAR component is moved in position, in particular repeatedly. The control of such a shift D can also be taken over by the control device 16. As a movable component that can be moved in position, and whose shift D can be used to increase the resolution, come now

Various in consideration. In particular, in this case a component of the transmitting unit 12 and / or the detection unit 14 can be moved. In particular, the detector 18 itself, or at least one component of the optics 25 associated with the detector 18, or the emitter arrangement 22 or at least a part of the optics 26 associated with the emitter arrangement 22 can be embodied as a movable component. Thus, temporally sequential partial images can be generated, wherein each partial image has a resolution as determined by the resolution of, for example, the detector matrix 18 or the

Emitter array 22 is specified. By a shift D by, for example, a half detector pixel width can through the combination of the two fields ideally double the resolution. This can in particular

corresponding image processing algorithms that can be executed by the control device 16 are used to process these partial images.

FIG. 2 shows a schematic illustration of a cross section through the detection unit 14 according to FIG

Embodiment of the invention. The detection unit 14 in turn has a detector 18 with a plurality of pixels 20 arranged at least in one row. These are arranged in a starting situation in a respective first position PI. Furthermore, each of these pixels 20 is assigned a corresponding solid angle range Q1, W2, W3 based on its position PI. This assignment is indicated schematically in FIG. 2 by ZI. If, for example, one of these pixels 20 receives a light pulse, then the

Controller 16 based on the information from which the pixel 20 has received this light pulse according to this assignment ZI determine from which direction

or from which of the solid angle ranges W1, W2, W3 the light pulse was received and thereby determine the direction in which the object is located, from which this light pulse was reflected. For a subsequent measurement can now advantageously the detector 18th

be moved. In particular, while the entire

Arrangement of the individual pixels 20, for example, by a half pixel width B as shown in Fig. 2, in a direction R shifted. The pixel width B can be defined as the length of the distance between two center points of respectively adjacent pixels in the direction R. In this pixel width B are also taken into account between the pixels 20 spaces. Thus, after this shift D, the pixel arrangement with the respective pixels 20 is now located at a position opposite the first position PI

shifted second position P2. Accordingly, the assignment Z2 to the respective solid angle ranges WI ',

W2 ', W3' shifted or changed. With others Words, each pixel 20 in the changed second position P2 now looks at a solid angle range WI ', W2', W3 'shifted or tilted relative to the solid angle ranges Q1, W2, W3 assigned in the first position PI. At a shift D of, for example, half

Pixel width B also overlap the associated

Solid angle segments or solid angle range W1, W1, W2, W2 ', W3, W3' in each case half. Thus, for these two different positions PI, P2

recorded partial images by means of a suitable

Image processing algorithm to a higher resolution

Combine overall picture.

To improve disturbance intervals can also several

Single pulse measurements are netted with each other to

For example, to improve the signal to noise ratio by averaging. So before corresponding subpictures from each

Positions PI, P2 were recorded, can be combined with each other before several such first fields and second fields are averaged over several measurements and then combined accordingly. It is preferred that a maximum of 100 consecutive measurements are averaged, especially if a measurement time window is two microseconds. In the case of shorter measuring time windows, correspondingly more averaging is possible.

For example, according to one embodiment

alternating measurements with the detector 18 in the first position PI and the second position P2 are performed. A displacement D of the movable component as here the detector 18 is not only possible in one direction, but for example in two mutually perpendicular directions. This can be done, for example, in the case of a flash LIDAR with a two-dimensional detector matrix 18

be beneficial. In this case, the resolution is provided solely by the detector array 18, and then in accordance with a movement of the detector in two

Spaces corresponding to the first and in Fig. 1 shown second dimension Dl, D2 correspond, a corresponding increase in resolution in these two dimensions Dl, D2 can take place. The sequence of movements may in principle be arbitrary, for example, the movable component of a first position PI in a second position P2 and then in a third position then in turn in the first position PI again in the second position P2 and so on. Of course, more than just three positions can be provided. The shift D of this movable component can thus not only follow such a regular scheme in which the individual

Positions in their temporal sequence are predetermined and fixed, but it can also be applied to a stochastic scheme. For example, the detector 18 may be randomized from the first position PI

between two extreme values selected second position P2 are moved. These two extreme values can define a minimum and a maximum position in the direction R. For example, it may be provided that the second

Position P2 is shifted by at least 10 percent of the pixel width B from the first position PI in the direction R, and at most by half the pixel width B. The same is true for the displacement D in a second dimension.

The achieved by the displacement D of the detector 18

However, advantages can also be achieved in the same way by shifting D of other movable components of the LIDAR system 10, which will now be described with reference to FIGS. 3 and 4

should be explained.

FIG. 3 shows a schematic cross-sectional representation of the detection unit 14 for a LIDAR system 10 according to an exemplary embodiment of the invention. The detection unit 14 in turn has a detector 18, which may be designed as described above. In addition, the

Detection unit 14 to the detector 18 associated optics 25. This optics 25 may have a secondary optics 28, which has the task, each a certain solid angle segment or a solid angle range Q1, W2, W3, WI ', W2', W3 'of the LIDAR viewing region to a mirror of the matrix, that is to say a corresponding pixel 20 of the detector 18,

map. It thus defines the field of view of the LIDAR system 10 over all solid angle segments.

Also, Fig. 4 shows a schematic representation of

Detection unit 14, as shown in Fig. 3

can be trained. In addition, the optics 25 assigned to the detector 18 now have a detector optics 30 in addition to the secondary optics 28. This can be formed for example as a microlens array. However, any other training options for these are

Detector optics 30 conceivable. The detector optics 30 is arranged between the secondary optics 28 and the actual detector 18 and can optimize the imaging of the solid angle ranges W1, W2, W3, WI ', W2', W3 'to the individual pixels 20. The detector optics 30 and / or the secondary optics of the detector can also have holographic optical elements.

In Fig. 3, in turn, as described also to Fig. 2, the movable component of the LIDAR system 10, the detector 18 is. This may turn in or opposite direction R, both optionally additionally in a further direction, preferably perpendicular to the direction R is to be moved, which is illustrated by the movement arrow 31. in the

In contrast, in Fig. 4, the movable component of the LIDAR system 10 is a part of the optical system 25, in particular in this example, the detector optics 30. These too

Detector optics 30 can now be moved in or against the direction R and optionally additionally in a second direction, which in turn is preferably perpendicular to the direction R, which is also indicated by the movement arrow 31

is illustrated. The movement of the detector optics 30 can be carried out as described for the movement of the detector 18.

In particular, the detector optics 30 can also be moved from a first position to a corresponding second position. This movement can also be a regular scheme follow or in turn a stochastic scheme.

In addition, the shift of the

Detector optics 30 by a maximum length of the pixel width B, preferably by a length corresponding to half the pixel width B, and in the case of a stochastic scheme by a length which is at least 10 percent and at most 50 percent of the pixel width B. The displacement of the detector 18 with respect to the optical system 25 and on the other hand, the displacement of an optical component relative to the detector 18 have the same technical effect. If, as shown in FIG. 4, the detector optics 30 are displaced, the assignment of the solid angle ranges Q1, Q2, W3 to the individual pixels 20 of the detector 18 also changes, as has already been described with reference to FIG.

Fig. 5 now shows a schematic representation in one

Cross section through the transmitting unit 12 for a LIDAR system 10 according to an embodiment of the invention. The

Transmitting unit 12 has an emitter arrangement 22 with a plurality of individual emitters 24 arranged in a one- or two-dimensional matrix. In addition, this emitter assembly 22 is associated with a corresponding optics 26. These

associated optics 26 may in turn include a secondary optics 32, which has the task of the light emission of

Single emitter 24 suitable to image in the far field. In the case of a pure flash LIDAR, therefore, each emitter 24 arranged in a two-dimensional matrix would be imaged into its own solid angle segment W1, W2, W3.

In addition, Fig. 6 shows a schematic

Cross-sectional view of the transmitting unit 12, which as shown in FIG.

5, but here additionally an emitter optic 34 as part of the optics 26, which is the

Emitter assembly 22 has associated. These

Emitter optic 34 can optionally be a deformation of the

Emitter emission for adaptation to secondary optics 32

guarantee . In the example of FIG. 5, the movable component of the LIDAR system 10 now represents the emitter arrangement 22. Displacement of the emitter arrangement 22, which in turn is illustrated by the movement arrow 31, also results in a displacement or tilting of the light emitted by the individual emitters 24 illuminated solid angle ranges Ql, Q2, W3. This also makes it possible to achieve an increase in resolution as in the displacement of the detector 18. As an alternative to a displacement of the emitter arrangement 22, a displacement of a part of the emitter arrangement 22 can also take place

associated optics 26 take place, as shown in Fig. 6

is shown. In this example, the

Emitter optics 34 shifted, which is illustrated by the movement arrow 31. Again, this causes a shift in the lit by the individual emitter 24

Solid angle ranges W1, W2, W3, which in turn one

Resolution increase can be achieved as described.

To shift these described movable components can generally an unillustrated actuator

be used. The actuator is preferably to

is configured to move the movable component in only one direction, but may optionally also be adapted to move the movable component in two independent directions. Especially in automotive applications, where usually a high horizontal resolution

desired, however, a high vertical resolution of

is downstream interest, a possibility of deflection of the movable component by the actuator in only one dimension or in only one direction is completely sufficient. Generally, however, are also two-dimensional

Movements possible. The minimum requirement on the amplitude of the movement, which can be implemented by the actuator,

results from the desired resolution improvement. For an increase, for example, by a factor of 2, the

movable component, such as the sensor array of the detector, by half the pixel width B relative to

Detector optics 30 are moved, which means the downstream optics 25 accordingly in the detected

Solid angle segments translated. At a typical width of a PIN diode along the narrow edge of 500

Microns would be a movement amplitude of about 250

Microns to generate a subpixel and approximately double the resolution. Also in this example, the pixel width already includes the optically inactive border area. Furthermore, the update rate of LIDAR data is typically in the range between 10 hertz and 200 hertz. A resolution increase by a factor of N in one dimension reduces the update rate accordingly. Depending on the application request, it is advantageous if the actuator thus necessary for the resolution increase

Can perform movement with a frequency in the range greater than 20 hertz. One possible embodiment of the actuator is in the form of a piezoelectric actuator having a piezoelectric element.

The movement of the emitter assembly 22 in at least one dimension relative to the _V orgesetzten optics 32, the

Radiation into the far field changed, so that also subpixels can be defined in this way. For example, LIDAR system 10 is a hybrid scanning LIDAR

formed, in which in one dimension

Rasterbildaufbau, in the second, however, a flash approach is used, then in the direction of the second dimension then one of the possibilities described above

Move the movable component are used to increase the resolution using temporally sequential fields.

Overall, so are by the invention and their

Embodiments provided numerous possibilities to detect the field of view of the LIDAR system particularly efficiently and to increase the resolution of the LIDAR system in a particularly effective manner. LIST OF REFERENCE NUMBERS

10 LIDAR system

12 transmitting unit

14 detection unit

16 control device

18 detector

20 pixels

22 emitter assembly

24 single emitter

25 optics

26 optics

28 secondary optics

30 detector optics

31 movement arrow

32 secondary optics

34 emitter optics

B pixel width

PI position

P2 position

R direction

D shift

Ql solid angle range

W2 solid angle range

W3 solid angle range

W1 'solid angle range

W2 'solid angle range

W3 'solid angle range

Claims

claims

1. LIDAR system (10) for environment detection,

- The lidar system (10) is adapted to measure the environment repeatedly measurements

perform,

- wherein the lidar system (10) has a transmitting unit (12), which is designed for the

Performing a measurement at least one

To emit light beam,

- wherein the lidar system (10) has a detection unit (14) which is designed to detect a steel portion reflected during a measurement,

- The lidar system (10) a control device

(16) which is designed, in the event that at least one reflected beam component is detected, to associate the detected beam component with a spatial angle range (Q1, W2, W3) on the basis of a predetermined assignment (ZI) from which the beam component originates,

characterized in that

the lidar system (10) at least one movable

Component (18, 22, 28, 20, 32, 34) and an actuator adapted to move the component (18, 22, 28, 20, 32, 34) from a first position (PI) in FIG

at least one from the first position (PI)

different second position (P2) to move, wherein, when the component (18, 22, 28, 20, 32, 34) is in the second position (P2), the assignment (Z2) is changed in a predetermined manner.

2. LIDAR system (10) according to claim 5,

characterized in that

the lidar system (10) is adapted to perform a first measurement in which the movable component (18, 22, 28, 20, 32, 34) in the first

Position (PI) and perform at least a second measurement in which the movable component (18, 22, 28, 20, 32, 34) is in the second position (P2), wherein the control means (16) is arranged to combine the first measurement and the at least one second measurement and a spatially resolved one based on the combination Provide measurement result, which has a resolution that is higher than one based on only the first or only the second measurement

provided spatially resolved measurement result.

3. LIDAR system (10) according to claim 1,

characterized in that

the component (18, 28, 30, 32, 34) forms part of

Detection unit (14) represents.

4. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

the detection unit (14) has a detector (18) with a plurality of pixels (20), the detector (18) representing the movable component (18).

5. LIDAR system (10) according to claim 3,

characterized in that

when the detector (18) is in the first position (PI), each of the pixels (20) is a respective one

predetermined first solid angle range (Q1, Q2, W3), wherein, when the detector (18) is in the second position (P2), each of the pixels (20) has a respective second solid angle range (Q1 ', W2', W3 '). ), wherein a respective second

Solid angle range (W1 ', W2', W3 ') at least partially different from a respective first solid angle range (W1, W2, W3), and preferably with a respective first solid angle range (W1, W2, W3) overlaps.

6. LIDAR system (10) according to one of claims 4 or 5,

characterized in that the pixels (20) of the detector (18) are arranged in a row in at least a first direction (R), a respective pixel (20) having a width (B) in the first direction (R), the detector (18 ) in the second position (P2) is shifted from the first position (PI) in the first direction (R) by less than a width (B) of a pixel (20).

7. LIDAR system (10) according to claim 6,

characterized in that

the detector (18) in the second position (P2) is shifted from the first position (PI) by half the width (B) of the pixel (20) in the row.

8. LIDAR system (10) according to claim 4 or 5,

characterized in that

the pixels (20) of the detector (18) are arranged in a row in at least a first direction (R), wherein a respective pixel (20) has a width in the first direction (R) and a second direction perpendicular to the first direction (R) Direction (R), has a length and a diagonal in a third direction extending between the first direction (R) and second direction, and wherein the detector (18) in the second position (P2) with respect to the first position (PI) in the third

Direction is shifted, in particular by less than a length of the diagonal of a pixel (20).

9. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

the actuator is designed to be the moving one

Component (18, 22, 28, 30, 32, 34) of the first

To move position (PI) to the second position (P2) in a first direction (R), and to move from the first position (PI) to a third position in a second direction different from the first direction (R), in particular, wherein the second direction to the first

Direction (R) is vertical.

10. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

the control device (16) is designed to randomly select at least the second position (P2) between a minimum position and a maximum position and to control the actuator for setting the second position (P2).

11. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

the detection unit (14) at least a first

optical element (28, 30), which the

movable component (28, 30) represents.

12. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

the component (22, 32, 34) constitutes a part of the transmitting unit (12).

13. LIDAR system (10) according to claim 5,

characterized in that

the transmitting unit (12) has an emitter arrangement (22)

comprising a plurality of emitter units (24) arranged in at least one row, wherein the

Emitter assembly (22), the movable component (22).

14. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

a respective emitter unit (24) in the first

Position (PI) of the emitter assembly (22) a respective one associated with the third solid angle range, which is illuminated by the respective emitter unit (24), wherein a respective emitter unit (24) in the second

Position (P2) of the emitter assembly (22) a respective of the respective third solid angle ranges at least partially different fourth solid angle range

assigned.

15. LIDAR system (10) according to one of the preceding

Claims,

characterized in that

the transmitting unit (12) has at least one second optical element (32, 34) which controls the movable one

Component (32, 34) represents.

16. A method for operating a LIDAR system (10), which performs repeated measurements for environment detection, which in each case at least one light beam from the lidar system (10) is emitted and in the event that during a measurement at least one reflected steel component is detected, the detected beam component based on a predetermined assignment (ZI) is assigned a solid angle range (Ql, W2, W3), from which the beam component comes from,

characterized in that

at least one movable component (18, 22, 28, 30,

32, 34) of the lidar system (10) is moved from a first position (PI) to at least one second position (P2) different from the first position (PI), in which the assignment (Z2) is predetermined

is changed.