Light distribution method for adaptive driving beam headlamp system, and adaptive driving beam headlamp system

• US 10,468,571 B2
• Filed: 01/29/2019
• Issued: 11/05/2019
• Est. Priority Date: 10/31/2014
• Status: Active Grant

• Current Assignee: Nichia Corporation
• Original Assignee: Nichia Corporation
• Inventors: Nakabayashi, Takuya
• Primary Examiner(s): A, Minh D
• Assistant Examiner(s): Cho, James H
• Application Number:
  US16/260,243
• Publication Number:
  US 20190157536A1
• Time in Patent Office: 280 Days
• Field of Search: None
• 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 1/16 illuminating the way asymmetrically
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: B60Q 2300/45 Special conditions, e.g. pedestrians, road signs or potential dangers
• CPC Class Codes: F21S 41/153 arranged in a matrix
• CPC Class Codes: F21S 41/18 Combination of light sources of different types or shapes
• CPC Class Codes: F21S 41/663 by switching light sources by switching incandescent light sources F21S41/162
• CPC Class Codes: F21Y 2105/10 comprising a two-dimensional array of point-like light-generating elements
• CPC Class Codes: F21Y 2105/12 characterised by the geometrical disposition of the light-generating elements, e.g. arranging light-generating elements in differing patterns or densities
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/18161 of a flip chip
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05K 1/0287 : having an universal lay-out, e.g. pad or land grid patterns or mesh patterns
• CPC Class Codes: H05K 1/111 : Pads for surface mounting, e.g. lay-out
• CPC Class Codes: H05K 2201/09663 : Divided layout, i.e. conductors divided in two or more parts branched layout H05K2201/09254
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

A light distribution method is for an adaptive driving beam headlamp system including a light emitting device, an on-board camera and an electronic control unit. The light distribution method includes: obtaining data indicative of a state in front of a vehicle by the on-board camera; computing one or more of: attributes of an object in front of the vehicle; attributes of a vehicle ahead; a speed of the vehicle ahead; a distance between vehicles; brightness of the object; and a road shape; determining a light distribution pattern; determining a control amount indicative of at least one of an ON or OFF state of each of the light emitting elements and an applied power to each of the light emitting elements according to the light distribution pattern determined; and controlling driving of the adaptive driving beam headlamp system based on the control amount determined.

Claims

1. A light distribution method for an adaptive driving beam headlamp system including a light emitting device, an on-board camera and an electronic control unit, the light emitting device including:

a substrate having a first main surface;

a plurality of first wiring members formed on the first main surface;

a plurality of second wiring members formed on the first main surface; and

a plurality of light emitting elements each including a first electrode, a second electrode, and a semiconductor stacked-layer structure, with the first electrode and the second electrode being disposed on the same face side of the semiconductor stacked-layer structure, the first electrode facing and being connected to a corresponding one of the first wiring members, the second electrode having a first connection part and a second connection part electrically connected to each other with electrode material, and the first connection part and the second connection part respectively facing at least two of the second wiring members and bridging the at least two of the second wiring members,

the light distribution method comprising;

obtaining data indicative of a state in front of a vehicle by the on-board camera;

computing, based on the data obtained, one or more of;

attributes of an object in front of the vehicle;

attributes of a vehicle ahead;

a speed of the vehicle ahead;

a distance between vehicles;

brightness of the object; and

a road shape;

determining a light distribution pattern based on a computed data;

determining a control amount indicative of at least one of an ON or OFF state of each of the light emitting elements and an applied power to each of the light emitting elements according to the light distribution pattern determined; and

controlling driving of the adaptive driving beam headlamp system based on the control amount determined.

2. The light distribution method according to claim 1, wherein

the determining of the light distribution pattern includes selecting one of a high-beam light distribution pattern, a focused light distribution pattern, a diffused light distribution pattern, and a low-beam light distribution pattern.

3. The light distribution method according to claim 1, wherein

a series of steps of the light distribution method is repeated at a prescribed interval.

4. The light distribution method according to claim 1, wherein

the obtaining of the data indicative of the state in front of a vehicle includes obtaining one or more of:

an image of an area in front of the vehicle, the vehicle speed, the distance between the vehicles, the road shape, and the light distribution pattern.

5. The light distribution method according to claim 1, wherein

the attributes of the object in front of the vehicle includes whether the object is a signal light or a street lamp,

the attributes of the vehicle ahead include whether the vehicle ahead is an oncoming vehicle, a vehicle driving ahead or a pedestrian, and

the road shape includes at least one of a lane width and whether the road is a straight road.

6. The light distribution method according to claim 1, wherein

the first electrode is connected to the corresponding one of the first wiring members via a stud bump or a solder ball, or

the second electrode is connected to the corresponding one of the second wiring members via the stud bump or the solder ball.

7. The light distribution method according to claim 1, wherein

the second electrode surrounds the first electrode, and

surfaces of the first electrode and the second electrode are located at the same height.

8. The light distribution method according to claim 1, wherein

each of the first wiring members has a region that faces the second electrode, and

an insulating protective film is formed on a surface of each of the first wiring members in the region or on a surface of the second electrode in the region.

9. The light distribution method according to claim 1, further comprising

a reflective member in contact with side surfaces of the light emitting elements.

10. The light distribution method according to claim 1, wherein

the plurality of light emitting elements is drive-controlled independently of each other.

11. The light distribution method according to claim 1, wherein

the first wiring members and the second wiring members are made of the same metal material.

12. The light distribution method according to claim 1, wherein

the substrate is a ceramic substrate with a single-layer structure.

13. The light distribution method according to claim 1, wherein

the first wiring members and the second wiring members are arranged in a regular pattern in column and row directions.

14. The light distribution method according to claim 1, wherein

at least one of the first wiring members or at least one of the second wiring members has a part that is partially branched.

15. The light distribution method according to claim 1, wherein

at least one of the second wiring members is wider than at least one of the first wiring members.

16. The light distribution method according to claim 1, wherein

the first wiring members extend in a first direction;

the second wiring members extend in a second direction, each of the second wiring members being segmented into a plurality of sections; and

the light emitting elements are aligned along the second direction,

the at least two of the second wiring members are separated from each other with respect to the second direction.

17. An adaptive driving beam headlamp system comprising:

an on-board camera configured to obtain data indicative of a state in front of a vehicle;

a light emitting device including;

a substrate having a first main surface;

a plurality of first wiring members formed on the first main surface;

a plurality of second wiring members formed on the first main surface; and

a plurality of light emitting elements each including a first electrode, a second electrode, and a semiconductor stacked-layer structure, with the first electrode and the second electrode being disposed on the same face side of the semiconductor stacked-layer structure, the first electrode facing and being connected to a corresponding one of the first wiring members, the second electrode having a first connection part and a second connection part electrically connected to each other with electrode material, and the first connection part and the second connection part respectively facing at least two of the second wiring members and bridging the at least two of the second wiring members; and

an electronic control unit configured to;

compute, based on the data obtained, one or more of;

attributes of an object in front of the vehicle;

attributes of a vehicle ahead;

a speed of the vehicle ahead;

a distance between vehicles;

brightness of the object; and

a road shape;

determine a light distribution pattern based on a computed data;

determine a control amount indicative of at least one of an ON or OFF state of each of the light emitting elements and an applied power to each of the light emitting elements according to the light distribution pattern determined; and

control driving of the adaptive driving beam headlamp system based on the control amount determined.