TRANSMITTING DEVICE FOR AN OPTICAL MEASURING DEVICE FOR DETECTING OBJECTS, LIGHT SIGNAL DEVICES DEVICE, MEASURING DEVICE AND METHOD FOR OPERATING A TRANSMITTING DEVICE

Description

Technical field

[0001] The invention relates to a transmitting device for an optical measuring device for detecting objects in a monitored area, with at least one transmitter light source for emitting light signals, with at least one light signal deflection device for deflecting the light signals into at least one monitoring area of ​​the measuring device, wherein the at least one light signal deflection device has at least one deflection area which can change the direction of the light signals depending on the incidence of the light signals, and with at least one drive device with which the incidence of the light signals on the at least one deflection area can be adjusted.

[0002] Furthermore, the invention relates to a light signal deflection device for a transmitter of an optical measuring device for detecting objects in a monitoring area, wherein the light signal deflection device has at least one deflection area which can change the direction of light signals from the transmitter depending on the incidence of the light signals.

[0003] Furthermore, the invention relates to an optical measuring device for detecting objects in a monitoring area, with at least one transmitting device for sending light signals into the monitoring area, at least one receiving device with which light signals reflected from objects present in the monitoring area can be received, and at least one control and evaluation device with which the at least one transmitting device and the at least one receiving device can be controlled and with which received light signals can be evaluated, wherein at least one transmitting device has at least one transmitter light source for emitting light signals, at least one light signal deflection device for deflecting the light signals into the at least one monitoring area, wherein the at least one light signal deflection device has at least one deflection area which can change the direction of the light signals depending on the incidence of the light signals, and at least one drive device.with which the incidence of the light signals on at least one deflection area can be adjusted.

[0004] Furthermore, the invention relates to a method for operating a transmitting device of an optical measuring device for detecting objects in a monitoring area, in which light signals are sent with at least one transmitter light source to at least one deflection area of ​​at least one light signal deflection device, with which at least one deflection area is used to change the direction of the light signals depending on the incidence of the light signals and to direct the light signals into the monitoring area, wherein the incidence of the light signals on the at least one deflection area is set with at least one drive device. State of the art

[0005] A deflection mirror arrangement for an optical measuring device is known from WO 2012 / 045603 A1. The optical measuring device comprises a housing with a base plate. The housing contains a transmitting window, through which, for example, pulsed laser light is emitted, and a receiving window, through which laser light reflected from objects in a monitoring area is received. A transmitting unit, a receiving unit, and a deflection mirror arrangement are arranged within the housing. The deflection mirror arrangement comprises a transmitting mirror unit with two transmitting deflection mirrors, which are arranged radially spaced apart on a support plate in a common horizontal plane, and a receiving mirror unit with two receiving deflection mirrors, which are each attached radially spaced to one side of a support body. The transmitting mirror unit and the receiving mirror unit are arranged axially spaced from each other on a common rotatable axis.A drive unit, which powers the rotating axis, is essentially located in the space between the two transmitting deflection mirrors. The stationary optical transmitter generates pulsed laser beams, which are deflected by the rotating transmitting mirror unit and emitted through the transmitting window into the area to be monitored.

[0006] DE 10 2017 116 598 A1 discloses a transmitting device for a detection system in which the beam direction of a transmitting beam can be swivelled in a monitoring area by controlling the phase of the transmitted signal using an optical phased array.

[0007] DE 10 2017 201 127 A1 discloses an optical arrangement for receiving light waves, comprising a receiving optic for focusing at least one incoming light wave onto a surface of a detector. At least one diffractive optical element with a planar extent is arranged between the receiving optic and the detector.

[0008] US 10 061 019 B1 discloses a lidar system in which light pulses can be deflected in different directions by a diffractive optical element depending on the wavelength of the light pulses in order to scan a field of view.

[0009] EP 2 492 738 A1 discloses a laser scanner in which a transmitted light beam is directed via a deflection unit through a beam rotation element and a rotating mirror into a monitoring area. The beam rotation element can be designed as a diffractive optical element.

[0010] The invention is based on the objective of designing a transmitting device, a light signal deflection device, an optical measuring device, and a method of the type mentioned above, in which the deflection of the light signals into the monitoring area can be simplified. In particular, the aim is to simplify the component effort, assembly effort, and / or adjustment effort, and / or to improve reliability, especially service life. Alternatively or additionally, an increase in the field of view and / or an improvement in resolution should be achieved. Disclosure of the invention

[0011] This problem is solved according to the invention by the features of independent claims 1, 12 and 13. Advantageous embodiments thereof are set forth in the dependent claims.

[0012] According to the invention, at least one diffractive structure is used to diffract the light signals and thereby change and / or adjust their direction. Diffractive structures can be easily implemented and handled. Adjustment effort can be reduced compared to known deflecting mirrors. The requirements regarding the quality of the light signals can be correspondingly lowered. Furthermore, diffractive structures can be individually adapted to achieve the desired direction-changing effect on the light signals.

[0013] Diffractive structures are known to be structures that can shape light beams, especially laser beams. This occurs through diffraction at optical gratings. Diffractive structures can be individually designed. They can be configured so that the direction of an incident light beam is altered depending on the angle of incidence and / or the point of incidence on the diffractive structure. Diffractive structures can operate in transmission and / or reflection modes.

[0014] Advantageously, at least one deflection region can be at least one diffractive structure. In this way, at least one deflection region exhibits at least one diffractive structure.

[0015] The invention enables the realization of a transmitter for an optical measuring device with a durable and maintenance-free light signal deflection device. Furthermore, the light signal deflection device can be designed to be simple and compact. This allows for high flexibility without the need for a complex optical design. Additionally, the measuring device according to the invention can capture a large field of view with high resolution. This reduces, for example, the need for large lenses on the transmitting or receiving side.

[0016] The at least one drive unit modifies the incidence of the light signals on the at least one deflection area. The incidence is characterized by the angle of incidence and the point of incidence where the light signal strikes the at least one deflection area. To change the incidence, either the angle of incidence or the point of incidence, or both, are altered.

[0017] The angle of incidence can advantageously be changed by rotating or pivoting the at least one deflection area relative to the beam direction of the incident light signal. Either the at least one deflection area, the transmitting light source, or both can be rotated or pivoted.

[0018] The point of incidence can advantageously be changed by shifting, in particular by means of a linear shift, the at least one deflection region relative to the beam direction of the incident light signal. Advantageously, the shift can be carried out transversely, in particular perpendicularly, to the beam direction of the incident light signal. Either the at least one deflection region or the transmitting light source, or both, can be shifted.

[0019] The incidence of light signals on at least one deflection area can be direct or indirect. In particular, a light signal coming from the transmitting light source can be indirectly directed onto the at least one deflection area by means of at least one upstream optical element. Additionally or alternatively, the light signal can be directed onto at least one rearward deflection area by means of at least one forward deflection area (viewed in the direction of the beam).

[0020] Advantageously, at least one emitted light signal can be implemented as a light pulse. The beginning and end of a light pulse can be determined, and in particular measured. In this way, light travel times can be determined.

[0021] Advantageously, at least one light signal can also contain additional information. For example, a light signal can be coded. In this way, it can be more easily identified and / or carry relevant information.

[0022] Advantageously, the optical measuring device can operate according to a time-of-flight method, in particular a time-of-flight method. Optical measuring devices operating according to the time-of-flight method can be designed and designated as Time-of-Flight (TOF), Light Detection and Ranging (LiDAR), Laser Detection and Ranging (LaDAR), or similar systems. In this method, the time of flight from the emission of a light signal by the transmitting device to the reception of the corresponding reflected light signal by a corresponding receiving device of the measuring device is measured, and from this, a distance between the measuring device and the detected object is determined.

[0023] Advantageously, the optical measuring device can be designed as a scanning system. In this system, a monitoring area can be scanned using light signals. For this purpose, the beam directions of the corresponding light signals can be swung across the monitoring area. At least one light signal deflection device is used for this.

[0024] Advantageously, the optical measuring device can be designed as a laser-based distance measuring system. The laser-based distance measuring system can have at least one laser, in particular a diode laser, as the transmitting light source. Pulsed laser signals, in particular, can be transmitted as light signals using the at least one laser. The laser can emit light signals in frequency ranges visible or invisible to the human eye. Accordingly, at least one receiving device can have a detector designed for the frequency of the emitted light, in particular an (avalanche) photodiode, a diode array, a CCD array, or the like. The laser-based distance measuring system can advantageously be a laser scanner. A monitoring area can be scanned with a laser scanner, in particular with pulsed laser signals.

[0025] The invention can advantageously be used in a vehicle, in particular a motor vehicle. Advantageously, the invention can be used in a land vehicle, in particular a passenger car, a truck, a bus, a motorcycle or the like, an aircraft and / or a watercraft. The invention can also be used in vehicles that can be operated autonomously or at least semi-autonomously. The invention can also be used in a stationary measuring device.

[0026] The measuring device can detect stationary or moving objects, in particular vehicles, persons, animals, obstacles, road surface irregularities, in particular potholes or stones, road boundaries, open spaces, in particular parking spaces, or the like.

[0027] Advantageously, the optical measuring device can be part of, or connected to, a driver assistance system and / or a vehicle's chassis control system. The information obtained with the optical measuring device can be used to control functional components of the vehicle. These functional components can be used to control, in particular, driving functions, especially steering, a braking system, and / or an engine, and / or signaling devices of the vehicle. Thus, when an object is detected by the optical measuring device, the vehicle can be steered and / or its speed changed, in particular stopped, and / or at least a signal can be output using the corresponding functional components.

[0028] In an advantageous embodiment, the at least one diffractive structure can be configured as a diffractive optical element. Diffractive optical elements (DoE) can be individually manufactured and adapted to the relevant requirements. With diffractive optical elements, a targeted and individually predefined modification, in particular diffraction, of the light signals can be achieved.

[0029] In a further advantageous embodiment, at least one deflection area can be transparent to the light signals.

[0030] Advantageously, the light signal deflection device can also have deflection areas which have a reflective effect on the light signals.

[0031] Alternatively, the light signal deflection device can have at least one translucent deflection area as well as at least one reflective deflection area.

[0032] Deflection zones that are transparent to light signals have the advantage that the light source can be located on the side opposite the monitored area. This way, there are no zones that are obscured by the transmitter's light source.

[0033] Reflective deflection areas have the advantage that they can radiate into the rear space where the at least one transmitting light source can be located. In particular, reflective deflection areas can be used when the deflection area is intended to be part of a position detection device for detecting the position or adjusting the light deflection device. In this case, the light signal can advantageously be encoded with corresponding position information using at least one diffractive structure of the at least one deflection area.

[0034] In a further advantageous embodiment, the at least one deflection area can be realized in, on, and / or on at least one substrate transparent to the transmitted light. The substrate can increase mechanical stability. Furthermore, the substrate can serve as a mechanical support. In particular, the substrate can be mounted on a corresponding axis about which it can be rotated or pivoted. This allows the incidence of the light signals on the at least one deflection area to be changed, and in particular, adjusted.

[0035] Advantageously, the substrate can be made of glass, plastic or the like, onto which the respective diffractive optical element can be realized by coating or ablation, in particular etching or the like.

[0036] Advantageously, at least one substrate can be implemented as a thin film.

[0037] In a further advantageous embodiment, the at least one deflection region can be arranged on the light-entry side of a substrate. According to the invention, at least one deflection region is arranged on the light-emission side of a substrate.

[0038] Deflection zones on the light-entry side allow the appropriate diffraction of the light signals before they enter the substrate. This allows the light to be directed within the substrate to different deflection zones located on the light-emission side.

[0039] According to the invention, deflection areas on the light output side direct the light signals directly into the monitoring area.

[0040] In a further advantageous embodiment, the at least one light signal deflection device can have at least two deflection areas arranged one behind the other with respect to the beam path of the light signals. In this way, depending on the incidence of the light signals on a first deflection area located ahead in the beam direction of the light signals, the light signals can be deflected by the front deflection area to a rear, second deflection area. Thus, the front deflection area can act as a kind of switch, by assigning the light signals to different rear deflection areas depending on the incidence of the light signals.

[0041] Advantageously, at least two deflection areas can be arranged diagonally one behind the other, directly behind the other, or partially overlapping one behind the other.

[0042] Advantageously, at least one front deflection area can be arranged on the front side of a substrate, the light-entry side, with respect to the direction of the light signals. At least one rear deflection area is arranged on the rear side, the light-emission side, of the substrate.

[0043] Advantageously, a front deflection area and at least two rear deflection areas can be provided. In this way, the light signals can be assigned to one of the at least two rear deflection areas depending on the incidence on the front deflection area. The rear deflection areas can have different properties with regard to the shaping of the light signals.

[0044] Advantageously, different diffraction angles for the light signals can be achieved using the rear deflection sections. In this way, the overall field of view of the light signal deflection device can be changed, and in particular, enlarged. The deflection of the light signal beam direction by the light signal deflection device consists of a corresponding angle of incidence of the light signals onto the front deflection section and a corresponding individual diffraction angle achieved by the respective rear deflection section. Overall, by pivoting or rotating the deflection sections, and especially the substrate on which the deflection sections are mounted, the beam direction of the light signals within the monitored area can be pivoted.

[0045] Advantageously, a large number of diffractive structures can be arranged on the light exit side. This allows for a correspondingly large number of different individual diffraction angles to be achieved along the extent of the deflection areas.

[0046] In a further advantageous embodiment, a direction-changing property of the at least one deflection area can vary across its extent in at least one direction of extension, and / or the at least one light signal deflection device can have at least two deflection areas with different direction-changing properties. With a deflection area whose direction-changing properties vary across its extent, a continuous variation in the direction of change of the light signals can be achieved, depending on the incidence of the light.

[0047] Alternatively or additionally, the at least one traffic signal deflection device can have at least two deflection areas with different direction-changing properties. In this way, the at least two deflection areas can act separately to change the direction of the traffic signals depending on their angle of incidence.

[0048] Advantageously, at least two deflection areas can be arranged side by side without gaps.

[0049] In a further advantageous embodiment, the at least one transmitting light source and / or the at least one deflection area of ​​the at least one light signal deflection device can be moved by at least one drive unit. In this way, the incidence of the light signals on the at least one deflection area can be adjusted, in particular changed, by means of the at least one drive unit.

[0050] Advantageously, at least one drive unit can implement a rotary drive, a linear drive, or another type of drive. This allows for corresponding rotational and / or displacement movements of the light signals relative to at least one deflection area.

[0051] Advantageously, at least one drive unit can comprise at least one motor, in particular a rotary motor, a linear motor, a linear DC motor, a voice coil motor, a voice coil drive, or the like, or another type of motor or actuator. Electric motors can easily be used to implement an electric drive. Voice coil motors, in particular, can be of simple design. They are easy to control and exhibit low wear. Furthermore, voice coil motors are brushless, which extends their service life and reduces maintenance. A voice coil motor can be used without polarity reversal, thus increasing operational reliability.

[0052] Voice coil motors consist of two separate parts: a magnetic housing and a coil. Applying a voltage moves the motor in one direction. Reversing the voltage moves the motor in the opposite direction. The force generated is proportional to the electric current through the coil. This force remains nearly constant within the specified stroke range of the voice coil motor.

[0053] Advantageously, the coil of the voice coil motor can act as the rotor and the magnet as the stator. This reduces the moving mass. The rotor requires a power supply.

[0054] Alternatively, the magnet of the voice coil motor can be implemented as the rotor and the coil as the stator. This eliminates the need for a separate power supply for the rotor. The correspondingly larger moving mass can be reduced by using rare-earth magnets.

[0055] Advantageously, at least one drive unit can be directly connected to the at least one deflection area, in particular to at least one substrate on which the at least one deflection area is implemented. In this way, the at least one deflection area can be accelerated and decelerated more quickly. Thus, compared to a conventional rotating mirror driven by a motor, the light signal deflection device according to the invention can be operated at a higher speed and with a longer service life.

[0056] Advantageously, the at least one deflection area, in particular the substrate on which the at least one deflection area is implemented, can be driven by rotation or vibration. Advantageously, the rotation angle of the at least one drive unit can be limited. In this way, the deflection of the light signals can be adjusted to the desired viewing area.

[0057] Advantageously, the same drive unit can be used for both the transmitting and receiving units of the optical measuring device. This reduces the number of drive units required.

[0058] Advantageously, the light signal deflection device of the transmitting device can be mechanically coupled to a corresponding light signal deflection device of the receiving device. In this way, both light signal deflection devices can be driven together.

[0059] Advantageously, the light signal deflection device of the receiving device can have at least one deflection area in the form of a diffractive structure.

[0060] Advantageously, at least one deflection area of ​​the transmitting device and at least one deflection area of ​​the receiving device can be implemented on a common substrate. In this way, the deflection areas can be manufactured together. Furthermore, the deflection areas can be easily moved using the substrate and a suitable drive mechanism.

[0061] Advantageously, at least one transmitting light source can be moved parallel to at least one deflection area using a linear drive. In this way, the points of incidence of the light signals on the at least one deflection area can be changed.

[0062] In a further advantageous embodiment, the at least one deflection area can be arranged to be rotatable and / or pivotable and / or displaceable, and / or the at least one transmitting light source can be arranged to be displaceable and / or rotatable and / or pivotable. In this way, the incidence of the light signals on the at least one deflection area can be changed by appropriately moving the at least one deflection area relative to the transmitting light source.

[0063] Advantageously, the at least one deflection area, in particular a substrate on which the at least one deflection area is arranged, and / or the at least one transmitting light source can have at least one axis of rotation and / or swiveling. In this way, the incidence can be changed in one spatial dimension. Alternatively or additionally, at least one deflection area, in particular a substrate on which the at least one deflection area is arranged, and / or at least one transmitting light source can have at least two axes of rotation or swiveling. In this way, corresponding rotation or swiveling in two dimensions can be performed. Accordingly, the monitored area can be scanned in two dimensions. Advantageously, the at least two axes of rotation or swiveling can be perpendicular to each other. In this way, efficient two-dimensional scanning can be achieved.

[0064] In a further advantageous embodiment, the at least one transmitting light source can comprise at least one laser. Light pulses can be emitted selectively using a laser. In this way, the distance of a detected object to the measuring device can be determined using a time-of-flight method. The at least one transmitting light source can consist of at least one laser. Alternatively, at least one laser component can be part of the at least one transmitting light source.

[0065] Advantageously, at least one emitting light source can comprise at least one surface emitter (VCSEL), one edge emitter, one fiber laser, one diode laser, or another type of laser, in particular a semiconductor laser. Such emitting light sources can be implemented simply and compactly.

[0066] Advantageously, the transmitting device can have more than one light source. This allows multiple deflection areas to be illuminated with corresponding light signals simultaneously or with a time delay. In this way, several light signals can be sent to different parts of the monitored area at the same time. This increases the frame rate when scanning the monitored area, resulting in a faster overall scan speed. Furthermore, combining multiple light sources with multiple deflection areas can increase the field of view of the measuring device.

[0067] Advantageously, at least one transmitting light source can be arranged on a holder of a linear displacement device. In this way, the transmitting light source can be moved with the displacement device, and thus the point of incidence of the light signals can be shifted accordingly to the at least one deflection area.

[0068] In a further advantageous embodiment, the transmitting device can have at least one optical system arranged between the at least one transmitting light source and the at least one deflection area. The optical system can shape the light signals accordingly, in particular focusing and / or widening them.

[0069] Advantageously, the at least one optical system can be designed such that it spreads, in particular fans out, the light signals in one spatial direction. In this way, a correspondingly larger section of the at least one deflection area can be illuminated in this spatial direction. Thus, the field of view of the measuring device can be expanded in this direction. Additionally, the spread-out light signals can illuminate at least one further deflection area, which, viewed in this spatial direction, can be arranged next to the at least one deflection area used to pivot the beam direction of the light signals. This further deflection area can be a position area of ​​a position detection device with which the position, in particular the pivot position, of the at least one deflection area can be determined.In this way, with just one transmitter light source, both the monitoring area can be scanned and the position, in particular the swivel position, of the at least one deflection area can be determined.

[0070] Alternatively or additionally, at least one optical system can be designed to focus the light signals in a specific spatial direction. This improves the resolution of the measuring devices in that direction. Advantageously, the spatial direction in which the light signals are spread out can be parallel to an axis about which the at least one deflection unit can be pivoted or rotated. This allows the monitored area to be scanned in the spatial direction perpendicular to the axis using the light signal deflection device.

[0071] Advantageously, at least one optical system can have at least one optical lens. An optical lens can be used to shape the light signals.

[0072] Furthermore, the object of the invention is achieved in the light signal deflection device by the fact that at least one deflection area has at least one diffractive structure.

[0073] According to the invention, the light signals are diffracted by the at least one diffractive structure. This allows the direction of the light signals to be changed simply and precisely.

[0074] Furthermore, the object of the invention is achieved in the optical measuring device by the fact that at least one deflection area of ​​the at least one transmitting device has at least one diffractive structure.

[0075] Advantageously, at least one transmitting device can be designed as a transmitting device according to the invention.

[0076] Advantageously, the at least one receiver can have at least one light signal deflection device. The at least one light signal deflection device on the receiver side can be constructed and / or operate according to the same principle as the at least one light signal deflection device on the transmitter side, in particular the transmitter according to the invention.

[0077] Advantageously, the at least one light signal deflection device on the receiver side can have at least one deflection area with at least one diffractive structure.

[0078] Advantageously, the at least one light signal deflection device, in particular the at least one deflection area, on the receiver side can be mechanically coupled to the at least one light signal deflection device on the transmitter side. In this way, the corresponding deflection areas can be set and, in particular, controlled together.

[0079] Alternatively, the at least one light signal deflection device on the receiver side can be operated separately from the at least one light signal deflection device on the transmitter side. The at least one light signal deflection device on the receiver side can also operate according to a different principle than the at least one light signal deflection device on the transmitter side.

[0080] Furthermore, the object of the invention is achieved in the method by adjusting the direction of the light signals using at least one diffractive structure.

[0081] According to the invention, at least one diffractive structure is used to adjust the beam direction of the light signals.

[0082] In an advantageous embodiment of the method, the at least deflection region and at least one transmitting light source can be moved relative to each other in order to change the incidence of the light signals on the at least one deflection region. In this way, depending on the given property of the at least one diffractive structure, a corresponding change in the direction of the light signal beam can be achieved.

[0083] Furthermore, the features and advantages described in connection with the inventive transmitting device, the inventive light signal deflection device, the inventive measuring device, and the inventive method and their respective advantageous embodiments apply to each other accordingly, and vice versa. The individual features and advantages can, of course, be combined with one another, potentially resulting in further advantageous effects that go beyond the sum of the individual effects. Brief description of the drawings

[0084] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are explained in more detail with reference to the drawing. The person skilled in the art will expediently consider the features disclosed in the drawing, the description, and the claims individually and combine them into meaningful further combinations. The drawing schematically illustrates Figure 1 shows a front view of a vehicle with an optical measuring device connected to a driver assistance system; Figure 2 shows an optical measuring device according to a first embodiment with a driver assistance system, which is integrated into the vehicle from the Figure 1 can be used; Figure 3 a light deflection device of a transmitting device of the measuring device from the Figure 2in a view in the direction of an axis with which the light signal deflection device can be pivoted; Figures 4 and 5 a transmitter of an optical measuring device according to a second embodiment, which has two transmitter light sources, wherein the light deflection device is shown in two different pivot positions; Figure 6 a transmitter of an optical measuring device according to a third embodiment, wherein the transmitter light source is linearly displaceable; Figures 7 to 9 a light signal deflection device of an optical measuring device according to a fourth embodiment in three different pivot positions.

[0085] In the figures, identical components are labelled with the same reference symbols. embodiment(s) of the invention

[0086] In the Figure 1Figure 10 shows a vehicle 10, for example a passenger car, in a front view. The vehicle 10 has an optical measuring device 12, for example a laser scanner. The optical measuring device 12 is, for example, located in a front bumper of the vehicle 10. Furthermore, the vehicle 10 has a driver assistance system 14, with which the vehicle 10 can be operated autonomously or semi-autonomously. The optical measuring device 12 is functionally connected to the driver assistance system 14 so that information obtained by the measuring device 12 can be transmitted to the driver assistance system 14. With the measuring device 12, a monitoring area 16, in the illustrated embodiment, in front of the vehicle 10 in the direction of travel, can be monitored for objects 18.

[0087] The measuring device 12 operates according to a time-of-flight method. For this purpose, light signals 20, for example in the form of laser pulses, are sent into the monitoring area 16. Light signals 22 reflected from any object 18 are received by the measuring device 12. The distance of the object 18 to the measuring device 12 is determined from the time of flight between the emission of the light signals 20 and the reception of the reflected light signals 22. The beam direction of the light signals 20 is swept across the monitoring area 16 during the measurements. In this way, the monitoring area 16 is scanned. From the beam direction of the light signals 20 reflected from the object 18, the direction of the object 18 relative to the measuring device 12 is determined.

[0088] The measuring device 12 comprises a transmitting device 24, a receiving device 26 and an electronic control and evaluation device 28.

[0089] The transmitting device 24, which is exemplified in the Figure 2 The system shown comprises a transmitting light source 30, an optical system in the form of a transmitting lens 32 and a transmitter light signal deflection device 34.

[0090] The receiving device 26 comprises an optical receiver 36, a receiver lens 38 and a receiver light signal deflection device 40.

[0091] The transmitter light source 30, for example, includes a laser. Pulsed laser signals can be generated as light signals 20 using the transmitter light source 30.

[0092] The transmitting lens 32 can spread the light signals 20 in a direction perpendicular to their beam direction. This in the Figure 2 indicated by a dashed trapezoid. In the illustrated embodiment, the light signals are spread out by the transmitting lens 32 in the direction of an axis 46, for example in the vertical direction.

[0093] The transmitter light signal deflection device 34 is located in the beam path of the transmitter light source 30 behind the transmitter lens 32. The transmitter light signal deflection device 34 allows the beam direction of the light signals 20 to be pivoted in a plane. For example, the pivoting plane is perpendicular to the direction in which the light signals 20 are widened by the transmitter lens 32, i.e., horizontally. In this way, the monitoring area 16 can be scanned horizontally with successive light signals 20.

[0094] The receiver-light signal deflection device 40 deflects light signals 22 reflected from the monitoring area 16 onto the receiver lens 38. The receiver lens 38 then images the reflected light signals 22 onto the receiver 36.

[0095] The receiver 36 is configured, for example, as a CCD chip, array, photodiode, or other type of detector for receiving the reflected light signals 22 in the form of laser pulses. The receiver 36 converts the received light signals 22 into electronic signals. These electronic signals are then transmitted to the control and evaluation unit 28.

[0096] The control and evaluation unit 28 controls the transmitting unit 24 and the receiving unit 26. Furthermore, the control and evaluation unit 28 evaluates the electronic signals derived from the received light signals 22. The control and evaluation unit 28 determines the light travel time and, from this, the distance to the object 18 from which the light signals 22 were reflected. The control and evaluation unit 28 also determines the direction of the object 18.

[0097] The transmitter light deflection device 24 includes, by way of example, a transmitter deflection area 42a in the form of a diffractive structure. The diffractive optical structure is implemented, for example, as a so-called diffractive optical element. The transmitter deflection area 42a is implemented, by way of example, on a rectangular, flat substrate 44. The substrate 44 is, for example, a glass plate or plastic plate, also as a thin film, which is transparent to the light signals 20. The transmitter deflection area 42a is arranged on the side of the substrate 44 that faces away from the transmitting lens 32. The transmitter deflection area 42a extends as a strip almost across the entire width of the substrate 44 transversely to the axis 46.

[0098] The substrate 44 is mounted on the axis 46. The axis 46 is driven by a motor 50, causing the substrate 44 and, with it, the deflection section 42a to pivot back and forth around the axis 46. The pivoting direction of the substrate 44 and thus of the deflection section 42a is specified in the Figure 2 indicated by a double arrow 48.

[0099] Motor 50, for example, is a voice coil motor. Motor 50 is controllably connected to the control and evaluation unit 28. However, instead of a voice coil motor, a different type of drive unit can also be used as motor 50.

[0100] The transmitter deflection area 42a is located, as in the Figure 3The beam path of the light signals 20 of the transmitting device 24 is shown. The light signals 20 are diffracted depending on their incidence onto the deflection area 42a. The incidence is defined by an angle of incidence 52 and a point of incidence 53. The angle of incidence 52 is the angle between an incident beam direction 54 of the light signals 20 and the entrance surface of the transmitter deflection area 42a.

[0101] The diffractive structure of the transmitter deflection area 42a is designed, for example, such that a diffraction angle 56 on the exit side relative to the exit surface of the deflection area 42a is constant, independent of the angle of incidence 52. A deflection angle 58 between the direction of incidence 54 and the direction of exit radiation 57 of the deflected light signals 20 is composed of the angle of incidence 52 and the constant diffraction angle 56. To change the deflection angle 58, the transmitter deflection area 42 is pivoted about the axis 46, which only results in a change in the angle of incidence 52. By pivoting the transmitter deflection area 42a, the direction of exit radiation 57 of the light signals 20 in the monitoring area 16 is thus pivoted. Using the swiveling transmitter deflection range 42a, a viewing area 64, which defines the monitoring area 16, can be scanned. The viewing area boundaries 49 of the viewing area 64 are shown in the Figure 3indicated with dashed lines.

[0102] The receiver light signal deflection device 40 comprises, as in the Figure 2 shown is a receiver deflection region 42b. The receiver deflection region 42b is a diffractive structure, for example a diffractive optical element.

[0103] In the illustrated embodiment, the receiver deflection area 42b is implemented on the same substrate 44 as the transmitter deflection area 42a. The receiver deflection area 42b is located on the side of the substrate 44 facing the receiver lens 38. The receiver deflection area 42b extends almost across the entire width of the substrate 44 transversely to the axis 46. The extent of the receiver deflection area 42b in the direction of the axis 46 is greater than the corresponding extent of the transmitter deflection area 42a.

[0104] In the illustrated embodiment, the transmitting light deflection device 34 and the receiver light signal deflection device 40 are mechanically coupled by means of the common substrate 44. This allows the transmitting deflection area 42a and the receiver deflection area 42b to be pivoted together with the axis 46. Only a single motor 50 is required for this purpose.

[0105] In an alternative embodiment not shown, the transmitter deflection area 42a and the receiver deflection area 42b can be implemented separately, for example, on separate substrates. The separate substrates can be mechanically connected to each other, for example, on a common axis, and driven together. The transmitter deflection area 42a and the receiver deflection area 42b can also be mechanically separated from each other. In this case, the transmitter comprises at least one transmitter deflection area 42a and its own drive unit. Likewise, the receiver comprises at least one receiver deflection area 42b and its own drive unit.

[0106] The receiver deflection area 42b is designed such that light signals 22 reflected by it, which originate from the monitoring area 16, are directed onto the receiver lens 38 in every pivot position of the receiver deflection area 42b, or of the substrate 44. The receiver lens 38 focuses the deflected reflected light signals 22 onto the receiver 36.

[0107] The measuring device 12 also includes a position detection device 60. The position detection device 60 can determine the pivot position of the substrate 44 and thus of the transmitter light deflection device 34 and the receiver light signal deflection devices 40.

[0108] The position detection device 60 comprises a position area 62 in the form of a diffractive structure, for example a diffractive optical element, and an optical position detector 66.

[0109] The position area 62 is arranged on the side of the substrate 44 facing the transmitting light source 30. The position area 62 is located, for example, between the transmitter deflection area 42a and the receiver deflection area 42b in the direction of the axis 46. The position area 62 extends as a strip, for example, perpendicular to the axis 46, almost across the entire width of the substrate 44. The position area 62 is arranged close enough to the transmitter deflection area 42 that a portion of the light signal 20, fanned out by the transmitting lens 32, is reflected, as shown in the Figure 2 shown, falling in position range 62.

[0110] The diffractive structure of the position area 62 is designed such that light signals 20 striking the position area 62 are encoded on the position area 62 depending on the angle of incidence 52 of the light signals 20. The encoding characterizes the respective angle of incidence 52. In the illustrated embodiment, the light signals 20 are encoded and reflected as position light signals 68 and sent to the position detector 66.

[0111] The position detector 66 is shown, by way of example, arranged at the same height as the transmitter light source 30. The position detector 66 can be configured, for example, as a single detector, a line detector, or an area detector. A CCD chip, a photodiode, or the like can be used for this purpose.

[0112] The coded light signals 68 are converted into electrical position signals by the position detector 66 and transmitted to the control and evaluation units 28. The control and evaluation units 28 use the electrical position signals to determine the swivel deflection of the position area 62 and thus the swivel deflection of the substrate 44, the transmitter deflection area 42a, and the receiver deflection area 42b. In this way, the swivel position of the transmitter light deflection device 34 and the receiver light signal deflection device 40 can be determined using the detection device 60.

[0113] In an embodiment not shown, the position area 62 can be configured for transmission instead of reflection of the light signals. In this case, the position detector 66 is located on the side of the position area 62 opposite the transmitter light source 30.

[0114] During operation of the measuring device 12, pulsed light signals 20 are sent by the transmitting light source 30 through the transmitting lens 32 to the transmit deflection area 42a and the position area 62.

[0115] The transmitter deflection range 42a directs the light signals 20 into the monitoring area 16 depending on the swivel position of the substrate 44, i.e., depending on the angle of incidence 52. The light signals 22 reflected from the object 18 are directed onto the receiver lens 38 by the receiver deflection range 42. The receiver lens 38 focuses the reflected light signals 22 onto the receiver 36. The receiver 36 converts the reflected light signals 22 into electrical signals and transmits them to the control and evaluation unit 28. The control and evaluation unit 28 determines the travel time of the light signals 20 and the corresponding reflected light signals 22 and uses this information to calculate the distance between the detected object 18 and the measuring device 12.

[0116] Furthermore, the portion of the light signals 20 that strikes the position area 62 is encoded and transmitted as position light signals 68 to the position detector 66. The pivot position of the transmitter light signal deflection device 34 and the receiver light signal deflection devices 40 is determined from the position light signals 68. The direction of the detected object 18 relative to the measuring device 12 is then determined from this pivot position.

[0117] During the measurement, the motor 50 rotates the axis 46, thereby pivoting the substrate 44 back and forth. In this way, successively emitted pulsed light signals 20 experience different deflections into the monitoring area 16. Thus, the monitoring area 16 is scanned with the pulsed light signals 20.

[0118] In the Figures 4 and 5A transmitting device 24 according to a second embodiment is shown, wherein the transmitter light signal deflection device 34 is depicted in two different pivoting positions. Those elements which correspond to those of the first embodiment from the Figures 2 and 3 Similar embodiments are provided with the same reference numerals. In contrast to the first embodiment, the transmitting device 24 of the second embodiment has two transmitting light sources 30, namely one in the Figures 4 and 5 left transmitter light source 30I and a right transmitter light source 30r, on.

[0119] Furthermore, the transmitter light deflection device 34 of the second embodiment has two transmitter deflection areas 42a, namely one in the Figures 4The left transmitter deflection area 42a-I and a right transmitter deflection area 42a-r are located. The two transmitter deflection areas 42a-I and 42a-r are arranged next to each other corresponding to the two transmitter light sources 30. Thus, each of the transmitter light sources 30 illuminates one of the transmitter deflection areas 42a-I or 42a-r.

[0120] The two transmitter deflection areas 42a-I and 42a-r have different deflection characteristics for light signals 20, specifically for the light signals 20I from the left transmitter light source 30I and the light signals 20r from the right transmitter light source 30r. Incident light signals 20r are deflected to the right by the right transmitter deflection area 42a-r with respect to a perpendicular to the surface of the transmitter deflection area 42a-r. Light signals 20I striking the left transmitter deflection area 42a-r are deflected to the left with respect to the perpendicular to the surface of the transmitter deflection area 42a-I. In this way, the field of view 64 of the measuring device 12, and thus the monitoring area 16, is extended compared to using only one transmitter deflection area 42a.

[0121] By pivoting the substrate 44 and thus the transmitter deflection areas 42a-I and 42a-r about the axis 46, the beam direction of the light signals 20I and 20r of the two transmitting light sources 30I and 30r is pivoted over the monitoring area 40. In the Figure 4 The transmitter light signal deflection device 34 is shown in a maximum swivel position to the right. Figure 5 The transmitter light signal deflection device 34 is shown in a maximum swivel position to the left.

[0122] The transmitting light sources 30I and 30r are operated simultaneously as an example. This allows two sections of the monitoring area 16 to be scanned at the same time. Alternatively, the transmitting light sources 30I and 30r can be operated alternately.

[0123] In the Figure 6 A transmitting light deflection device 34 according to a third embodiment is shown. Those elements which correspond to those of the first embodiment from the Figures 2 and 3Similar embodiments are provided with the same reference numerals. In contrast to the first embodiment, in the third embodiment the substrate 44 is not pivotable. Instead, the transmitting light source 30 is linearly displaceable in a displacement direction 70 parallel to the surface of the substrate 44 and thus parallel to a transmitter deflection area 42a-var by means of a linear motor (not shown).

[0124] The transmitter deflection area 42a-var is a diffractive structure, for example a diffractive optical element, whose direction-changing properties vary with respect to the light signals 20 in the displacement direction 70 of the linear motor. For example, the diffraction angle 56 between the beam direction of the diffracted light signals 20 and the surface of the transmitter deflection area 42a-var in the Figure 6 From right to left, for example, continuously. Light signals 20, which are in the Figure 6The light rays entering the transmitter deflection region 42a-var at the right position of the transmitter light source 30 at a right incidence point 53r are deflected to the right. Figure 6 At the left position of the transmitter light source 30, which is indicated by a dashed line, the light signals 20, which hit a left point of incidence 53I, are deflected to the left.

[0125] Alternatively, instead of a single transmitter deflection area 42a-var with varying diffraction angle 56, a plurality of individual transmitter deflection areas 42a with different diffraction angles 56 can be arranged next to each other.

[0126] In the Figures 7 to 9 A transmitting light signal deflection device 34 according to a fourth embodiment is shown in different pivot positions. Those elements which correspond to those of the first embodiment from the Figures 2 and 3Similar components are provided with the same reference numerals. In the fourth embodiment, the transmitting light signal deflection device 34, unlike the first embodiment, has, by way of example, three transmitting deflection areas 42a on the side facing away from the transmitting lens 32, namely one in the Figures 7 to 9 left transmitter deflection range 42a-I, a middle transmitter deflection range 42a-m and a right transmitter deflection range 42a-r.

[0127] The transmitter deflection ranges 42a have different direction-changing properties with respect to the light signals 20. For example, the one in the Figures 7 to 9 The right transmitter deflection area 42a-r emits the light signals 20 with a fixed diffraction angle α relative to the surface of the transmitter deflection area 42a-r, as shown in the Figure 9 shown, only slightly. The one in the Figures 7 to 9The central transmitter deflection area 42a-m deflects light signals 20 with a fixed diffraction angle β relative to the surface of the transmitter deflection area 42a-m, as shown in the Figure 8 shown, turning right. The one in the Figures 7 to 9 The left transmitter deflection area 42a-I deflects light signals 20 with a fixed diffraction angle γ relative to the surface of the transmitter deflection area 43a, as shown in the Figure 7 shown, turning left.

[0128] Furthermore, on the side of the substrate 44 facing the transmitter light source 30, another transmitter deflection region 42a, namely a forward transmitter deflection region 42a-v (viewed in the direction of the light signals 20), is arranged. The forward transmitter deflection region 42c is a diffractive structure, in particular a diffractive optical element. The forward transmitter deflection region 42a-v is located in front of the axis 46 at the center of the substrate 44. In this way, the forward transmitter deflection region 42a-v is struck by light signals 20 directed towards the axis 46.

[0129] The front transmitter deflection area 42a-v is designed such that, depending on the angle of incidence 52 of the light signals 20 incident in the direction of incidence 54, i.e. depending on the pivot position of the transmitter light signal deflection device 34, it deflects the light signals 20 to one of the three rear transmitter deflection areas 42a-I, 42a-m or 42a-r.

[0130] In the Figure 7The transmitting light deflection device 34 is shown in its maximum right-hand pivot position. In this pivot position, the incoming light signals 20 are deflected to the left by the front transmitter deflection area 42a-v onto the left transmitter deflection area 42a-I. The light signals 20 are deflected to the left by the left transmitter deflection area 42a-I with a diffraction angle γ. Overall, this deflects the exit beam direction 57 of the light signals 20 in the area of ​​the center of the monitoring area 16.

[0131] By pivoting the substrate 44 to the left, the exit beam direction 57 is pivoted further to the left until the incident light signals 20, which are diffracted by the front transmitter deflection area 42a-v, leave the left transmitter deflection area 42a-I and instead meet the middle transmitter deflection area 42a-m.

[0132] With the medium transmitter deflection range 42a-m, the light signals 20 are in the in the Figure 8The center swivel position shown is directed to the right side of the monitoring area 16.

[0133] By pivoting the substrate 44 to the left, the exit beam direction 57 is pivoted further to the left until the incident light signals 20, which are diffracted by the front transmitter deflection area 42a-v, leave the middle transmitter deflection area 42a-m and instead meet the right transmitter deflection area 42a-r.

[0134] The right transmitter deflection section 42a-r directs the light signals 20 into the left area of ​​the monitoring area 16. As the transmitter light signal deflection device 34 continues to swivel to the left, the light signals 20 scan the left area of ​​the monitoring area 16 until the transmitter light signal deflection device 34 reaches its position in the Figure 9 The left swivel position shown has been reached. In the left swivel position, the light signals 20 are directed to the left side of the monitoring area 16.

[0135] The direction of rotation of the transmitter light signal deflection device 34 is then reversed, so that the right area of ​​the monitoring area 16 and subsequently the middle area of ​​the monitoring area 16 are scanned with the light signals 20 using the middle transmitter deflection range 42a-m and the left transmitter deflection range 42a-I.

[0136] By using the different diffraction angles α, β, γ of the three transmitter deflection ranges 42a, namely 42a-I, 42a-m and 42a-r, in combination with the swivel angle of the transmitter light signal deflection device 34 about the axis, a correspondingly larger viewing area 64 is swivelled than is possible with only one transmitter deflection range 42a from the first embodiment.

[0137] In further embodiments not shown, the features of the different transmitter light signal deflection devices 34, as described in the Figures 2 to 9The diagrams shown can also be used for different receiver light signal deflection devices 40. In particular, receiver deflection ranges can be implemented similarly to the transmitter deflection ranges described.

Claims

1. Transmitting device (24) for an optical measuring device (12) for detecting objects (18) in a monitoring area (16), - with at least one transmitter light source (30) for emitting light signals (20), with at least one light signal deflection device (34) for deflecting the light signals (20) into at least one monitoring area (16) of the measuring device (12), wherein the at least one light signal deflection device (34) has at least one deflection area (42a), which acts on the light signals (20) to change direction depending on an angle of incidence (52) and / or a point of incidence (53) of the light signals (20), - and with at least one drive device (50), with which angle of incidence (52) and / or point of incidence (53) of the light signals (20) on the at least one deflection area (42a) is adjusted, wherein the at least one deflection area (42a) has at least one diffractive structure, characterized in that the at least one deflection area (42a) is arranged on the light exit side of a substrate (44) in order to direct the light signals (20) directly into the monitoring area (16).

2. Transmitting device according to claim 1, characterized in that the at least one diffractive structure (42a) is designed as a diffractive optical element.

3. Transmitting device according to claim 1 or 2, characterized in that the at least one deflection area (42a) acts transparently for the light signals (20).

4. Transmitting device according to one of the preceding claims, characterized in that the at least one deflection area (42a) is realized in, on and / or upon at least one substrate (44) that is transparent for the transmitted light.

5. Transmitting device according to one of the preceding claims, characterized in that the at least one deflection area (42a) is arranged on the light entry side of a substrate (44).

6. Transmitting device according to one of the preceding claims, characterized in that the at least one light signal deflection device (34) has at least two deflection areas (42a) that are arranged one behind the other with respect to the beam path of the light signals (20).

7. Transmitting device according to one of the preceding claims, characterized in that a direction-changing property of the at least one deflection area (42a-var) varies over its extent in at least one direction of extent and / or the at least one light signal deflection device (34) has at least two deflection areas (42a) with different direction-changing properties.

8. Transmitting device according to one of the preceding claims, characterized in that the at least one transmitter light source (30) and / or the at least one deflection area (42a) of the at least one light signal deflection device (34) is movable with at least one drive device (50).

9. Transmitting device according to one of the preceding claims, characterized in that the at least one deflection area (42a) is arranged to be rotatable and / or pivotable and / or displaceable and / or the at least one transmitter light source (30) is arranged to be displaceable and / or rotatable and / or pivotable.

10. Transmitting device according to one of the preceding claims, characterized in that the at least one transmitter light source (30) comprises at least one laser.

11. Transmitting device according to one of the preceding claims, characterized in that the transmitting device (24) has at least one optical system (32) which is arranged between the at least one transmitter light source (30) and the at least one deflection area (42a).

12. Optical measuring device (12) for detecting objects (18) in a monitoring area (16), with - at least one transmitting device (24) for transmitting light signals (20) into the monitoring area (16), - at least one receiving device (26), with which light signals (22) reflected from objects (18) present in the monitoring area (16) can be received, - and with at least one control and evaluation device (28), with which the at least one transmitting device (24) and the at least one receiving device (26) can be controlled and with which received light signals (22) can be evaluated, wherein at least one transmitting device (24) comprises - at least one transmitter light source (30) for emitting light signals (20), - at least one light signal deflection device (34) for deflecting the light signals (20) into the at least one monitoring area (16), wherein the at least one light signal deflection device (34) has at least one deflection area (42a), which acts on the light signals (20) to change direction depending on an angle of incidence (52) and / or a point of incidence (53) of the light signals (20), - and at least one drive device (50), with which angle of incidence (52) and / or point of incidence (53) of the light signals (20) on the at least one deflection area (42a) is adjusted, wherein at least one deflection area (42a) of the at least one transmitting device (24) has at least one diffractive structure, characterized in that at least one deflection area (42a) is arranged on the light exit side of a substrate (44) in order to direct the light signals (20) directly into the monitoring area (16).

13. Method for operating a transmitting device (24) of an optical measuring device (12) for detecting objects (18) in a monitoring area (16), in which light signals (20) are sent with at least one transmitter light source (30) onto at least one deflection area (42a) of at least one light signal deflection device (34), with the at least one deflection area (42a) changing a direction of the light signals (20) depending on an angle of incidence (52) and / or a point of incidence (53) of the light signals (20) and directing the light signals (20) into the monitoring area (16), wherein angle of incidence (52) and / or point of incidence (53) of the light signals (20) on the at least one deflection area (42a) is adjusted with at least one drive device (50), wherein the direction of the light signals (20) is adjusted by means of at least one diffractive structure of the deflection area (42a), characterized in that the light signals (20) are directed directly into the monitoring area (16) by means of the at least one deflection area (42a) arranged on the light exit side of a substrate (44).

14. Method according to claim 13, characterized in that the at least one deflection area (42a) and the at least one transmitter light source (30) are moved relative to each other in order to change the angle of incidence (52) and / or the point of incidence (53) of the light signals (20) on the at least one deflection area (42a).