Automatic headlamp control

• US 7,131,754 B2
• Filed: 02/27/2006
• Issued: 11/07/2006
• Est. Priority Date: 04/23/2002
• Status: Active Grant

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: Schofield, Kenneth
• Primary Examiner(s): Alavi, Ali
• Application Number:
  US11/363,100
• Publication Number:
  US 20060139937A1
• Time in Patent Office: 253 Days
• Field of Search: 362464-466, 315/82, 250/205, 382/104
• US Class Current: 362/466
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: B60Q 2300/054 Variable non-standard intensity, i.e. emission of various beam intensities different from standard intensities, e.g. continuous or stepped transitions of intensity
• CPC Class Codes: B60Q 2300/146 Abnormalities, e.g. fail-safe
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/41 preceding vehicle
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: G06V 20/584 of vehicle lights or traffic lights

Abstract

An automatic headlamp control system includes an image sensor and a control. The image sensor captures an image of a forward exterior scene and the control processes the image to determine if any light sources in the captured image are indicative of headlamps of oncoming vehicles or taillights of leading vehicles. The control adjusts the state of the headlamps between a high beam state and a lower beam state in response to such processing, and may adjust the beam illumination state of one headlamp independent of adjustment of the beam illumination state of the other headlamp. The control adjusts one headlamp to its lower beam state in response to a detection of a headlamp of an approaching vehicle in the forward field of view, and adjusts or maintains the beam illumination state of the other headlamp independent of the adjustment of the first headlamp in response to the detection.

Claims

1. An automatic headlamp control system for controlling the beam illumination state of headlamps of a vehicle, said automatic headlamp control system comprising:

a first headlamp located at a front driver side of the vehicle and a second headlamp located at an opposing front passenger side of the vehicle, each of said first and second headlamps comprising a high beam lighting element for providing high beam illumination in a high beam state and a lower beam lighting element for providing lower beam illumination in a lower beam state;

an image sensor having a field of view forwardly of the vehicle, said image sensor capturing image data of a scene forwardly of the vehicle;

a control operable to process said image data to determine if a light source within the scene is indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle;

said control being operable to adjust the beam illumination state of said first headlamp between its high beam state and its lower beam state independent of adjustment of said second headlamp between its high beam state and its lower beam state; and

said control adjusting said first headlamp to its lower beam state in response to a determination that a detected light source in the captured image is indicative of a headlamp of an approaching vehicle in the forward field of view, said control adjusting or maintaining the beam illumination state of said second headlamp independent of the adjustment of said first headlamp in response to the determination.

2. The automatic headlamp control system of claim 1, wherein said control ramps energization and deenergization of the lighting elements of said first and second headlamps when adjusting the beam illumination state of said first and second headlamps.

3. The automatic headlamp control system of claim 2, wherein said control is operable to ramp up energization of the lower beam lighting element of said first headlamp while ramping down energization of the high beam lighting element of said first headlamp to provide a generally continuous output of said first headlamp during a transition period as said first headlamp is adjusted from its high beam state to its lower beam state.

4. The automatic headlamp control system of claim 3, wherein said control is operable to adjust the beam illumination state of said second headlamp from its lower beam state to its high beam state while adjusting the beam illumination state of said first headlamp from its high beam state to its lower beam state.

5. The automatic headlamp control system of claim 1, wherein said control is operable to adjust said second headlamp to its high beam state in response to a determination that a detected light source in the captured image is a reflection of at least one of said headlamps of the controlled vehicle.

6. The automatic headlamp control system of claim 1, wherein said control is operable to provide a warm-up current to at least one of (a) said high beam lighting element and (b) said lower beam lighting element when adjusting the beam illumination state of said first or second headlamp.

7. The automatic headlamp control system of claim 6, wherein said control is operable to provide said warm-up current to the high beam lighting element in response to a determination that a condition surrounding the vehicle is appropriate for high beam illumination.

8. The automatic headlamp control system of claim 7, wherein said control is operable to provide said warm-up current to the high beam lighting element to warm up the high beam filament without providing high beam illumination.

9. The automatic headlamp control system of claim 6, wherein said control is operable to provide said warm-up current in response to a determination that a condition surrounding the vehicle is appropriate for adjustment of the beam illumination state of the headlamp.

10. The automatic headlamp control system of claim 9, wherein said determination that a condition surrounding the vehicle is appropriate for adjustment of the beam illumination state is made in response to at least one of an ambient light level and a quantity of light sources in said captured image.

11. The automatic headlamp control system of claim 1 including a manual input device, the high beam lighting element of at least one of said first and second headlamps being activatable in response to actuation of said manual input device.

12. An automatic headlamp control system for controlling the beam illumination state of headlamps of a vehicle, said automatic headlamp control system comprising:

a first headlamp located at a front driver side of the vehicle and a second headlamp located at an opposing front passenger side of the vehicle, each of said first and second headlamps comprising a high beam lighting element for providing high beam illumination in a high beam state and a lower beam lighting element for providing lower beam illumination in a lower beam state;

an image sensor having a field of view forwardly of the vehicle, said image sensor capturing image data of a scene forwardly of the vehicle;

a control operable to process said image data to determine if a light source within the scene is indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle;

said control being operable to independently adjust the beam illumination states of said first and second headlamps; and

said control adjusting said first headlamp to its lower beam state in response to a determination that a detected light source in the captured image is indicative of a headlamp of an approaching vehicle in the forward field of view, said control adjusting or maintaining the beam illumination state of said second headlamp independent of the adjustment of said first headlamp in response to the determination; and

said control ramping energization and deenergization of the lighting elements of said first and second headlamps when adjusting the beam illumination state of said first and second headlamps.

13. The automatic headlamp control system of claim 12, wherein said control is operable to adjust said second headlamp to its high beam state in response to a determination that a detected light source in the captured image is a reflection of at least one of said headlamps of the controlled vehicle.

14. The automatic headlamp control system of claim 12, wherein said control is operable to provide a warm-up current to at least one of (a) said high beam lighting element and (b) said lower beam lighting element when adjusting the beam illumination state of said first or second headlamp.

15. The automatic headlamp control system of claim 12 including a manual input device, the high beam lighting element of at least one of said first and second headlamps being activatable in response to actuation of said manual input device.

16. An automatic headlamp control system for controlling the beam illumination state of headlamps of a vehicle, said automatic headlamp control system comprising:

a first headlamp located at a front driver side of the vehicle and a second headlamp located at an opposing front passenger side of the vehicle, each of said first and second headlamps comprising a high beam lighting element for providing high beam illumination in a high beam state and a lower beam lighting element for providing lower beam illumination in a lower beam state;

an image sensor having a field of view forwardly of the vehicle, said image sensor capturing image data of a scene forwardly of the vehicle;

a control operable to process said image data to determine if a light source within the scene is indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle;

said control being operable to independently adjust the beam illumination states of said first and second headlamps;

said control adjusting said first headlamp to its lower beam state in response to a determination that a detected light source in the captured image is indicative of a headlamp of an approaching vehicle or a taillight of a leading vehicle in the forward field of view, said control adjusting or maintaining the beam illumination state of said second headlamp independent of the adjustment of said first headlamp in response to said determination; and

wherein said control is operable to provide a warm-up current to at least one of (a) said high beam lighting element and (b) said lower beam lighting element when adjusting the beam illumination state of said first or second headlamp.

17. The automatic headlamp control system of claim 16, wherein said control ramps energization and deenergization of the lighting elements of said first and second headlamps when adjusting the beam illumination state of said first and second headlamps.

18. The automatic headlamp control system of claim 16, wherein said control is operable to adjust said second headlamp to a high beam state in response to a determination that a detected light source in the captured image is a reflection of at least one of said headlamps of the controlled vehicle.

19. The automatic headlamp control system of claim 16 including a manual input device, the high beam lighting element of at least one of said first and second headlamps being activatable in response to actuation of said manual input device.