TRANSMISSION UNIT AND LIDAR DEVICE INCLUDING IMPROVED OPTICAL EFFICIENCY

Abstract

A transmission unit for a LIDAR device for emitting collimated beams into a scanning area. The transmission unit includes at least one beam source for generating beams in the form of a beam bundle, the beam source being designed as a surface emitter or an emitter array, and a transmission optical unit including at least one lens. The transmission unit includes a diaphragm including at least one aperture, which is configured to delimit a cross section of the beam bundle of the generated beams in a horizontal direction and/or a vertical direction. The at least one lens of the transmission optical unit is situated downstream from the diaphragm in the emission direction of the beams. A LIDAR device is also described.

Claims

1-10. (canceled)

11. A transmission unit for a LIDAR device for emitting collimated beams into a scanning area, the transmission unit comprising: at least one beam source configured to generate beams in the form of a beam bundle, the beam source being configured as a surface emitter or an emitter array; a transmission optical unit including at least one lens; and a diaphragm with at least one aperture, which is configured to delimit a cross section of the beam bundle made up of the generated beams in a horizontal direction and/or a vertical direction, the at least one lens of the transmission optical unit being situated downstream from the diaphragm in an emission direction of the beams.

12. The transmission unit as recited in claim 11, wherein the at least one lens of the transmission optical unit includes a focal length which is configured to collimate the beams exiting from the diaphragm.

13. The transmission unit as recited in claim 12, wherein the at least one lens of transmission optical unit has a focal length of at least 40 mm.

14. The transmission unit as recited in claim 11, wherein the aperture of the diaphragm has an extension in the horizontal direction and/or the vertical direction, by which an edge section of the beam bundle made up of the generated beams is blocked.

15. The transmission unit as recited in claim 14, wherein the edge section of the beam bundle made up of the generated beams which is blocked by the diaphragm includes a portion of at least 10% of a total radiant energy of the generated beams.

16. The transmission unit as recited in claim 11, wherein to increase an eye safety limiting value, at least regional lateral blocking of the generated beams by the diaphragm is provided.

17. The transmission unit as recited in claim 11, wherein the generated beams have a linear cross section or a rectangular cross section, the generated beams having a greater extension in the vertical direction than in the horizontal direction.

18. The transmission unit as recited in claim 11, wherein the at least one aperture of the diaphragm has a round cross section, or an oval cross section, or a rectangular cross section, or a square cross section, or a linear cross section.

19. The transmission unit as recited in claim 11, further comprising: a rotatable or pivotable mirror element downstream from the at least one lens of the transmission optical unit or the diaphragm or the transmission unit, and the mirror is rotatable or pivotable.

20. A LIDAR device for scanning a scanning area using beams, comprising: a transmission unit configured to emit collimated beams into the scanning area, including: at least one beam source configured to generate beams in the form of a beam bundle, the beam source being configured as a surface emitter or an emitter array, a transmission optical unit including at least one lens, and a diaphragm with at least one aperture, which is configured to delimit a cross section of the beam bundle made up of the generated beams in a horizontal direction and/or a vertical direction, the at least one lens of the transmission optical unit being situated downstream from the diaphragm in an emission direction of the beams; and a receiver unit configured to receive beams reflected and/or backscattered from the scanning area.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG. 1 shows a schematic representation of a LIDAR device according to an exemplary embodiment of the present invention.

[0043] FIG. 2 shows a top view of a transmission unit of the LIDAR device from FIG. 1.

[0044] FIG. 3 shows a side view of a transmission unit of the LIDAR device from FIG. 1.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0045] FIG. 1 shows a schematic representation of a LIDAR device 1 according to one exemplary embodiment. LIDAR device 1 is used to scan a scanning area A and includes a transmission unit 2 and a receiver unit 4.

[0046] Transmission unit 2 is configured to generate electromagnetic beams 6 and emit them at a varying scanning angle a into scanning area A.

[0047] For this purpose, transmission unit 2 includes a beam source 8 for generating electromagnetic beams 6. According to the exemplary embodiment, beam source 8 is designed as a semiconductor laser. Beam source 8 may be an arbitrary laser or an LED. Furthermore, beam source 8 may be designed as an array made up of a plurality of lasers and/or LEDs. For example, beam source 8 may be designed as a surface emitter.

[0048] Beam source 8 includes an emission area extended in vertical direction V, by which generated beams 6 are generated in the form of a line. This is illustrated in FIG. 3. In horizontal direction H, the emission area of beam source 8 has an essentially punctiform extension.

[0049] Generated beams 6 may be, for example, in a wavelength range visible or invisible to the human eye, for example, the infrared range or UV range. Generated beams 6 are generated in the form of a one-part or multipart beam bundle by beam source 8.

[0050] The beam bundle made up of generated beams 6 is reduced in its cross section by a diaphragm 10. Diaphragm 10 includes an aperture 12, through which generated beams 6 may pass diaphragm 10. Beams in an edge section 7 of the beam bundle are blocked by diaphragm 10.

[0051] A lens 14 of a transmission optical unit 16 is connected downstream from diaphragm 10. Lens 14 is a convex lens which is usable, for example, to collimate generated beams 6. Beams 9 which have passed aperture 12 have a slightly lower radiant power since edge sections 7 of the beam bundle are blocked by diaphragm 10.

[0052] The beams which are collimated or at least preformed by lens 14 may subsequently be deflected by a mirror element 18 along an axis of rotation R.

[0053] Mirror element 18 may be designed, for example, as a cube prism, a mirror, a MEMS mirror, and the like.

[0054] The beams deflected by mirror element 18 may be formed by a further lens 20 of transmission optical unit 16 and subsequently emitted into scanning area A.

[0055] Generated beams 6 may be collimated by first lens 14, by second lens 20, or by a combination of both lenses 14, 20 of transmission optical unit 16.

[0056] Beams 22 which are backscattered or reflected in scanning area A are received by receiver unit 4 and detected. For this purpose, receiver unit 4 includes, for example, a receiver optical unit 24 and a detector 26.

[0057] Beams 22 detected by detector 26 of receiver unit 4 may subsequently be evaluated.

[0058] FIG. 2 shows a top view of transmission unit 2 of LIDAR device 1 from FIG. 1. In particular, the extension of generated beams 6 in horizontal direction H is illustrated. Diaphragm 10 delimits the beam bundle made up of generated beams 6 in horizontal direction H and blocks beams of edge section 7.

[0059] To illustrate the effect of the diaphragm, a beam profile 28 before diaphragm 10 and the beam profile 30 after diaphragm 10 are shown. Beam profiles 28, 30 describe a radiant energy along a cross section of generated beams 6 and beams 9 after passing diaphragm 10.

[0060] In the illustrated exemplary embodiment, beams 6 are exclusively delimited at the edge along horizontal direction H by diaphragm 10. In vertical direction V, for example, no blocking of beams 6 takes place due to diaphragm 10.

[0061] Diaphragm 10 and corresponding aperture 12 may be designed in such a way that beams 6 are blocked at the edge both in vertical direction V and in horizontal direction H.

[0062] FIG. 3 shows a side view of transmission unit 2 of LIDAR device 1 from FIG. 1 and illustrates the propagation of beams 6 in emission direction Z and along vertical direction V. It is illustrated that first lens 14 of transmission optical unit 16 is formed as a cylinder lens and generated beams 6 may pass in vertical direction V uninfluenced by the diaphragm.

[0063] Furthermore, it is illustrated by FIG. 3 that beam source 8 enables a linear illumination and an emission area extended in vertical direction V for emitting beams 6.