IR ILLUMINATOR WITH SECONDARY FUNCTION

Abstract

An IR illuminator used during the operation of autonomous vehicles, which provides improvement in the performance of cameras used in the vehicle at night time. An optical design of an outer lens of the IR illuminator is selected so that the outer lens forms a beam pattern for the output light from the IR light source, and also acts as a light guide for light emitted from a secondary visible light source, which is located in the same module as the IR light source, and which may be positioned on the same or a different printed circuit board as the IR light source. The material of outer lens is opalescent including scattering bodies. The optical design of the outer lens allows for improved field of view of the IR illuminator.

Claims

1. An infrared (IR) illuminator device for a vehicle, comprising: a housing; one or more IR light emitting diodes (LEDs) positioned on a first printed circuit board (PCB) inside the housing to perform IR illumination for the vehicle; and an outer lens at one side of the housing having a first section comprising a first surface and a second surface, and covering the one or more IR LEDs, so that light rays emitted from the one or more IR LEDs are incident on the first surface, are refracted through the body and exit through the second surface, wherein the outer lens is made of an opalescent material and includes scattering bodies therein, and the first and second surfaces of the outer lens have a free form profile so that the field of view (FOV) of the emitted light is increased from 140 to 180.

2. The IR illuminator device according to claim 1, wherein the outer lens comprises a second section which receives light from a secondary light source positioned on a second PCB inside the housing and guides the received light through the body of the outer lens to exit the second surface of the outer lens.

3. The IR illuminator device according to claim 2, wherein the secondary light source comprises a plurality of LEDs.

4. The IR illuminator device according to claim 3, wherein the plurality of LEDs emit light in the visible wavelength range.

5. The IR illuminator device according to claim 2, wherein the second PCB is the same as the first PCB.

6. The IR illuminator device according to claim 2, further comprising a light guide section, separate from the outer lens, which guides light emitted from the one or more IR LEDs to the first surface of the outer lens.

7. The IR illuminator device according to claim 2, wherein the second section receives light exterior to the IR illuminator device and guides the received light through the body of the outer lens to a sensor positioned on a third PCB.

8. The IR illuminator device according to claim 2, wherein the light emitted by the secondary light source is arranged to perform one of a plurality of secondary operations for the vehicle operation, including: indication of autonomous mode of operation of the vehicle, warning signaling, side marking signaling.

9. The IR illuminator device according to claim 8, wherein the secondary light source emits light in the cyan wavelength range or white light to indicate autonomous operation of the vehicle.

10. The IR illuminator device according to claim 8, wherein the secondary light source emits light in the red wavelength range to indicate rear side marking, tail marking, or stop signaling.

11. The IR illuminator device according to claim 8, wherein the secondary light source emits light in the yellow wavelength range to indicate front side marking.

12. The IR illuminator device according to claim 1, wherein four IR LEDs are positioned on the first PCB inside the housing.

13. The IR illuminator device according to claim 2, wherein the IR illumination due to the one or more IR LEDs and the secondary operation due to the secondary light source are performed independently.

14. The IR illuminator device according to claim 7, wherein the received exterior light includes high speed data transmitted to the vehicle or ambient light.

15. An Autonomous Vehicle (AV) comprising: a sensor system including a vision camera; and one or more infrared (IR) illuminator devices, the one or more IR illuminator devices including: a housing, one or more IR light emitting diodes (LEDs) positioned on a first printed circuit board (PCB) inside the housing to perform IR illumination for the AV, and an outer lens at one side of the housing having a first section comprising a first surface and a second surface, and covering the one or more IR LEDs, so that light rays emitted from the one or more IR LEDs are incident on the first surface, are refracted through the body and exit through the second surface, wherein the outer lens is made of an opalescent material and includes scattering bodies therein, and the first and second surfaces of the outer lens have a free form profile so that the field of view (FOV) of the emitted light is increased from 140 to 180, the one or more IR illuminator devices being positioned relative to the vision camera linearly or in an arc.

16. The AV according to claim 15, wherein the outer lens comprises a second section which receives light from a secondary light source positioned on a second PCB inside the housing and guides the received light through the body of the outer lens to exit the second surface of the outer lens.

17. The AV according to claim 16, the IR illuminator further comprising a light guide section separate from the outer lens that guides light emitted from the one or more IR LEDs to the first surface of the outer lens.

18. The AV according to claim 16, wherein the second section receives light exterior to the one or more IR illuminator devices and guides the received light through the body of the outer lens to a sensor positioned on a third PCB.

19. The AV according to claim 16, wherein the light emitted by the secondary light source is arranged to perform one of a plurality of secondary operations for the AV operation, including: indication of autonomous mode of operation of the AV, warning signaling, side marking signaling.

20. The AV according to claim 16, wherein the secondary light source comprises a plurality of visible LEDs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The invention will be better understood in light of the description which is given in a non-limiting manner, accompanied by the attached drawings in which:

[0015] FIG. 1 is a schematic view of an AV illustrating the camera and other sensor-based sensing zones of the vehicle.

[0016] FIG. 2A is a schematic view of a conventional IR illuminator with a clear outer lens.

[0017] FIG. 2B is a schematic view of a conventional IR illuminator with a black, IR transparent, outer lens.

[0018] FIG. 3 is a schematic view of an IR illuminator using free form optical concept for increased FOV.

[0019] FIG. 4A, FIG. 4B and FIG. 4C are schematic views of an IR illuminator using free form optical concept for increased FOV with 4 IR LEDs with specifics of the LEDs and the outer lens.

[0020] FIG. 5 shows graphs that show the improvement of FOV of the IR illuminator due to free form concept design over the conventional outer lens of a conventional IR illuminator.

[0021] FIG. 6 is a schematic view of an embodiment of an IR illuminator using free form optical concept for increased FOV that provides secondary lighting function, the IR illuminator including an IR LED and a visible LED.

[0022] FIG. 7A and FIG. 7B show ray tracing graphs for light travelling inside the IR illuminator using free form optical concept with 4 IR LEDs.

[0023] FIG. 8 is a schematic view of another embodiment of an IR illuminator using free form optical concept for increased FOV that provides secondary lighting function.

[0024] FIG. 9 is a schematic view of another embodiment of an IR illuminator using free form optical concept for increased FOV that provides secondary function.

[0025] FIG. 10 is a schematic view of relative positioning between the IR illuminator and a camera in a camera pod.

[0026] FIG. 11 is a schematic view of different possible relative positions between the IR illuminator and a camera in a camera pod.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Referring to FIG. 3, a light module 4 comprises an IR LED 5 that is positioned on a PCB/Sink 6 inside a housing 7. An outer lens 8 covers one side of the housing 7. Light rays 9 emitted by IR LED 5 are incident on first surface 10 of lens 8, are refracted, travel through the body of lens 8, and exit the second surface 11. The first and second surfaces of lens 8 are designed to have a free form profile (not a sphere or ellipse) and are not offsets with constant thickness, creating optical power. The shape of the surfaces may also be optimized for light guiding.

[0028] It is desirable to increase the FOV of the IR illuminator emission pattern and to improve beam uniformity to improve the camera performance for the camera used together with the IR illuminator. The free form profile of the IR illuminator lens 8 allows for the FOV to increase from 140 to 180 (to match the FOV of the camera) and to improve uniformity over the FOV.

[0029] The above optical concept for the profile of the surfaces of the lens 8 can be used with different numbers of IR LEDs, e.g., 1, 2, 3, 4 . . . .

[0030] A 4-LED design is shown in FIG. 4 with information about the specifics of the LEDs and the outer lens.

[0031] FIG. 5 includes a graph showing the FOV improvement for the free form concept.

[0032] Referring now to FIG. 6, a light module 12 comprises an IR LED 13 that is positioned on a PCB/Sink 14 inside a housing 15. An outer lens 16 covers one side of the housing 15. Light rays 17 emitted by IR LED 13 are incident on first surface 18 of lens 16, are refracted, travel through the body of lens 16, and exit the second surface 19. The first and second surfaces of lens 16 are designed to have a free form profile.

[0033] It is desirable to have the IR illuminator serve a secondary lighting function using the same emitting surface. To achieve this, the free form concept can be enhanced by making the lens of an opalescent material (for example, Evonik Endlighten, or similar) that includes scattering bodies. The optical design may be modified to allow input from a second LED group, without negative impact on the IR performance. The characteristic shape of the free form first and second surfaces of the outer lens 16 allows for efficient light guiding of the secondary LED group.

[0034] A secondary light source comprising a visible LED 20 is positioned on a PCB 21 inside the housing 15. The outer lens 16 includes a secondary light guiding section, for example, on the left side, which receives light rays 22 emitted by the visible LED 20 and guides them into the main body of the lens 16. The light rays 22 exit the lens 16 through the second surface 19.

[0035] The secondary light source may include one or more visible LEDs. In non-limiting embodiments, the visible LEDs may be cyan, red, yellow, or RGB (red, green, blue), depending on the particular secondary lighting function desired.

[0036] For example, a list of possible secondary lighting functions with corresponding visible LEDs as secondary light sources for the IR illuminator includes: [0037] Indication of autonomous mode vehicle operation (cyan LED) [0038] Signature lighting (user controlled color, RGB LED) [0039] Warning (red LED) [0040] Side marking (yellow LED at the front of the car, red LED at the back of the car)

[0041] It is noted that for the IR illuminator with secondary function to be used for side marking, it will need to be positioned (along with the accompanying camera pod) on the car to meet side marker regulations.

[0042] FIG. 7A and FIG. 7B include ray tracing graphs that show that light from the secondary LEDs is sufficiently guided through the base and over the dome of the outer lens 16.

[0043] Referring to FIG. 8, another non-limiting embodiment is shown, where both the IR LED 23 and the secondary LEDs 24 are placed on the same PCB 25 inside the housing 26. In addition, an additional light guide 27, separate from the outer lens 28 having a free form profile, is positioned to receive light rays from the IR LED 23 and guide them towards the outer lens 28. The outer lens 28 also receives and guides light rays from the secondary visible LEDs 24.

[0044] In another non-limiting embodiment, shown in FIG. 9, the secondary, light guiding portion 29 of the outer lens 30 with the free form profile may be used to receive external light 31 and guide it towards a detector 32 inside the IR illuminator 33. The received light 31 may be ambient light or contain data. For example, the data may be data/software updates. A car may be parked at a charging station and while the car is charging, high speed data is transmitted from a base station to the car (the IR illuminator pod being on the outside of the vehicle). In addition, this embodiment may be used for car-to-car communications as well.

[0045] The above discussed type of profile for the outer lens for the IR illuminator can be easily adapted to be extruded in linear fashion or in an arc relative to the camera. As shown in FIG. 10, the IR illuminator 34 can be placed in a pod linearly with respect to the camera, or it can be placed in an arc fashion to surround the camera (see middle of FIG. 11). The lens optical cross section 34 can be extruded in different ways to make rectangular lenses or round lenses for the corresponding positioning geometries.

[0046] The sensor system for the AV, that includes the IR illuminator described in the present application, comprises a central unit comprising at least one computer, for example, one or more microprocessors, for implementing the particular driving assistance method, for example, associating the received detector signals from the cameras, radars, LIDAR, etc. with corresponding outputs, e.g., images, sounds, etc., in order to assist in the driving operation of the AV. This central unit may be placed at any location of the motor vehicle, for example, may be integrated into the on-board computer of the motor vehicle. Alternatively, it may be placed within the camera pods. The sensor system further comprises communication means connecting the camera or the other sensors to the central unit, so that images from the cameras or other sensed data are received and processed by the central unit. The central unit further includes imaging processing software for the information necessary for driving assistance.

[0047] Numerous modifications and variations of the present disclosure are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the described features may be practiced otherwise than as specifically described herein.