LIDAR SENSOR

Abstract

A LIDAR sensor, which includes a transmitting unit and a deflection unit. The transmitting unit is configured to generate a laser beam, whose local beam distribution includes a double peak distribution along a deflection direction of the deflection unit. The light energy of which in a central section between the two peaks is less by a predefined factor than the light energy in sections in each case laterally adjacent thereto, which include the peaks. The deflection unit is configured to deflect the laser beam generated by the transmitting unit along the deflection direction into surroundings of the LIDAR sensor.

Claims

1. A LIDAR sensor, comprising: a transmitting unit; and a deflection unit; wherein the transmitting unit is configured to generate a laser beam whose local beam distribution along a deflection direction of the deflection unit includes a double peak distribution including two peaks, light energy of which in a central section between the two peaks is less by a predefined factor than light energy in sections in each case laterally adjacent to the central section which include the peaks, and wherein the deflection unit is configured to deflect the laser beam generated by the transmitting unit along the deflection direction into surroundings of the LIDAR sensor.

2. The LIDAR sensor as recited in claim 1, wherein a height of the peaks of the double peak distribution and/or a width of the peaks of the double peak distribution and/or a spacing of the peaks of the double peak distribution are established in accordance with predefined eye safety requirements of the LIDAR sensor.

3. The LIDAR sensor as recited in claim 2, wherein the LIDAR sensor is configured to ensure the eye safety requirements in a close range of a light exit interface of the LIDAR sensor, the close range corresponding to a distance of up to 10 m from the light exit interface of the LIDAR sensor.

4. The LIDAR sensor as recited in claim 3, wherein the close range corresponds to a distance of up to 5 m.

5. The LIDAR sensor as recited in claim 4, wherein the close range corresponds to a distance of up to 1 m.

6. The LIDAR sensor as recited in claim 1, wherein the light energy in the central section of the beam distribution corresponds maximally up to 50% which is present in each case in sections including the peaks.

7. The LIDAR sensor as recited in claim 1, wherein the light energy in the central section of the beam distribution corresponds maximally up to 20% which is present in each case in sections including the peaks.

8. The LIDAR sensor as recited in claim 1, wherein the light energy in the central section of the beam distribution corresponds maximally up to 10% which is present in each case in sections including the peaks.

9. The LIDAR sensor as recited in claim 1, wherein a width of sections including the peaks corresponds to 2% to 30% of a total width of the laser beam along the deflection direction.

10. The LIDAR sensor as recited in claim 1, wherein a width of sections including the peaks corresponds to 5% to 25% of a total width of the laser beam along the deflection direction.

11. The LIDAR sensor as recited in claim 1, wherein the laser beam exiting the LIDAR sensor is a collimated laser beam and a local spacing between the two peaks at a light exit interface is at least 1 cm.

12. The LIDAR sensor as recited in claim 1, wherein the laser beam exiting the LIDAR sensor is a collimated laser beam and a local spacing between the two peaks at a light exit interface is at least 1.5 cm.

13. The LIDAR sensor as recited in claim 1, wherein the laser beam exiting the LIDAR sensor is a collimated laser beam and a local spacing between the two peaks at a light exit interface is at least 2.0 cm.

14. The LIDAR sensor as recited in claim 1, wherein the LIDAR sensor is configured to generate the double peak distribution using: a plurality of optically coupled semiconductor lasers; and/or an optical system in an optical path of the LIDAR sensor.

15. The LIDAR sensor as recited in claim 12, wherein the optical system includes a cube-shaped optical element, which is situated within the optical path of the LIDAR sensor in such a way that two opposing edges with respect to a focal point of the cube are situated within the optical path.

16. The LIDAR sensor as recited in claim 1, wherein the transmitting unit is configured to emit laser light at a wavelength in a near-infrared range.

17. The LIDAR sensor as recited in claim 1, wherein the LIDAR sensor is a point scanner or a line scanner.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Exemplary embodiments of the present invention are described in detail below with reference to the figures.

[0023] FIG. 1 schematically shows a top view of a LIDAR sensor according to the present invention in a first specific embodiment of the present invention.

[0024] FIG. 2 shows an example of a local beam distribution of a laser beam of a LIDAR sensor according to an example embodiment of the present invention.

[0025] FIG. 3a schematically shows a representation of a local distribution of a laser beam of the LIDAR sensor according to an example embodiment of the present invention.

[0026] FIG. 3b shows a temporal profile of the laser beam corresponding to FIG. 3a as it is viewed by an observer.

[0027] FIG. 4 schematically shows a representation of an optically coupled semiconductor laser stack.

[0028] FIG. 5 schematically shows a top view of a LIDAR sensor according to the present invention in a second specific embodiment of the present invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0029] FIG. 1 schematically shows a top view of a LIDAR sensor according to the present invention in a first specific embodiment. The LIDAR sensor, which is designed here as a line scanner, includes a transmitting unit 10, which includes a plurality of stacks made up of five optically coupled laser diodes 12 each. Laser diodes 12 of the individual stacks are aligned here in each case transversely to the direction of resulting laser beam 15, whereas the respective stacks in the top view are situated one above the other. Laser diodes 12 in this case each emit light in the near-infrared wavelength range.

[0030] Optically coupled laser diodes 12 each generate a beam distribution, which corresponds to the above-described double peak distribution according to the present invention. A central section 40 of laser beams 15 of the respective stacks of laser diodes situated one above the other includes proportional light energy, which corresponds to maximally 10% of the light energy in respective edge sections 45 of laser beams 15. A width of edge sections 45, which include peaks 50 of the double peak distribution, corresponds here to approximately 25% of a total width of respective laser beams 15, whereas 95% of the light energy of laser beams 15 is situated here within a beam angle in the deflection direction of the LIDAR sensor of approximately 40°. The LIDAR sensor further includes a deflection unit 20, which is configured to deflect laser beams 15 generated by transmitting unit 10 and shaped by an optical system 90 along a deflection direction 30 into surroundings 60 of the LIDAR sensor.

[0031] On the basis of the preceding configuration, the LIDAR sensor is configured to ensure eye safety for an observer of laser beam 15 in a close range 70, which is defined here by a distance of up to 1 m with respect to a light exit window 80 of the LIDAR sensor.

[0032] FIG. 2 shows an example of a local beam distribution of a laser beam 15 of a LIDAR sensor according to the present invention. The beam distribution represents a local distribution of light energy E of the laser beam over distance d. A width 17 of laser beam 15 is also defined here, within which preferably 95% of the light energy of laser beam 15 is located.

[0033] FIG. 3a schematically shows a representation of a local distribution of a laser beam 15 of the LIDAR sensor according to the present invention at different points in time t1, t2, and t3, which is generated by a transmitting unit 10. Laser beam 15, which includes the local distribution according to the present invention shown close to eye 100, is deflected by a deflection unit 20 (not shown) of the LIDAR sensor in deflection direction 30. As a result, peaks 50 of laser beam 15 strike the retina of eye 100 at different points in time, as a result of which eye safety of the LIDAR sensor is correspondingly enhanced with such a distribution.

[0034] FIG. 3b shows a temporal profile of the laser beam corresponding to FIG. 3a as it is viewed by an observer. The temporally offset striking of peaks 50 in eye 100 of the observer described in FIG. 3a, in particular, may be seen in FIG. 3b.

[0035] FIG. 4 schematically shows a representation of an optically coupled semiconductor laser stack of a transmitting unit 10 of the LIDAR sensor according to the present invention, the semiconductor laser stack here including by way of example five laser diodes 12, which are situated one above the other on a substrate 110. A local distribution resulting from the optical coupling of laser beams 15 of this stack corresponds to the above-described double peak distribution.

[0036] FIG. 5 schematically shows a top view of a LIDAR sensor according to the present invention in a second specific embodiment. The LIDAR sensor in the second specific embodiment includes a transmitting unit 10, which includes a plurality of stacks of optically non-coupled laser diodes 12, here each stack including an arrangement of three laser diodes 12 each. Laser beams 12 generated by this transmitting unit 10 each include a local distribution that corresponds to a Gaussian shape. The LIDAR sensor in the second specific embodiment also includes an optical system 90, which influences laser beams 15 of transmitting unit 10 in a suitable manner. As a result of cube-shaped optical element 95 in the optical path of the LIDAR sensor, a double peak distribution according to the present invention is generated, which ensures the eye safety of this LIDAR sensor in the close range of the LIDAR sensor. To avoid repetitions, a deflection unit 20 of the LIDAR sensor is not represented here.