Apparatus for controlling a headlight of a vehicle

• US 4,891,559 A
• Filed: 12/28/1987
• Issued: 01/02/1990
• Est. Priority Date: 06/13/1985
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd., NIPPONDENSO SOKEN, INC.
• Original Assignee: Nippondenso Co., Ltd., NIPPONDENSO SOKEN, INC.
• Inventors: Matsumoto, Muneaki, Nishida, Minoru, Numata, Koji, Masegi, Mitsuhiko, Akita, Shigeyuki
• Primary Examiner(s): NOT, DEFINED
• Assistant Examiner(s): Palladino, Brian
• Time in patent office: 736 Days
• Field of Search: 315/80, 315/81, 315/82, 315/83, 315/79, 362/63, 362/64, 362/65, 362/66, 362/71, 250/211 R
• US Class Current: 315/82
• 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 2300/052 Switching delay, i.e. the beam is not switched or changed instantaneously upon occurrence of a condition change
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/132 Pitch
• CPC Class Codes: B60Q 2300/3321 Detection of streetlights
• CPC Class Codes: B60Q 2300/41 preceding vehicle
• CPC Class Codes: B60Q 2300/42 oncoming vehicle
• CPC Class Codes: B60Q 2300/45 Special conditions, e.g. pedestrians, road signs or potential dangers

Abstract

In an apparatus for controlling a headlight of a vehicle, a light from a preceding or oncoming vehicle can be detected without being disturbed by a light reflected on guardrails and the like, or light from a traffic signal, street lights and the like, and the illumination area of the headlight can be suitably adjusted without unnecessary switching of an illumination mode of the headlight. This control is carried out by receiving a light impinging on the front end of the vehicle by a light receiving member divided into a plurality of regions, by carrying out a comparison and discrimination between the light detection signals from the plurality of regions, and based on a result thereof, by selecting an appropriate illumination mode of the headlight.

Claims

1. A computer-controlled apparatus for controlling a headlight of a vehicle comprising:

light detecting means for receiving a light impinging on a front end of the vehicle, including a photosensor having a plurality of photoelectric elements at least one of which is a special photoelectric element, said light detecting means for generating a plurality of light detection signals, each said light detection signal corresponding respectively to a quantity of the light received in each of said photoelectric elements, said special photoelectric element being arranged in a central portion of said photosensor and receiving an increased incident range of angles of light on the upper side thereof as compared with others of said photoelectric elements;

control means, coupled to receive said light detection signals from said light detecting means, for;

(1) comparing a level of at least one of said light detection signals corresponding to a quantity of light received in a predetermined photoelectric element with a predetermined level;

(2) discriminating a presence or absence of a preceding vehicle or an oncoming vehicle based on a distribution of a quantity of light received at said plurality of photoelectric elements;

(3) selecting a high beam mode or low beam mode as an illumination mode of a headlight of said vehicle based on a result of said comparing and discriminating; and

(4) generating a control signal for commanding said selected high beam mode or low beam mode; and

illumination switching means for receiving said control signal from said control means and switching the illumination mode of said headlight to obtain said selected high beam mode or low beam mode.

2. An apparatus according to claim 1, wherein said plurality of photoelectric elements are arranged such that a range of angles of light incident on the upper side of said photosensor which can be detected, is increased in a central portion of said photosensor, and the light detection signal of said special photoelectric element is used as a signal for said discriminating for switching the illumination of the headlight of said vehicle.

6. An apparatus according to claim 1, wherein a sensitivity of said at least one special photoelectric element is made lower than that of each of the remaining photoelectric elements.

3. A computer-controlled apparatus for controlling a headlight of a vehicle comprising:

a speed sensor for generating a running condition signal representing a running condition of said vehicle;

light detecting means for receiving a light impinging on a front end of the vehicle using a light receiving member divided into first regions extending in the vertical direction and covering a predetermined range in the horizontal direction and second regions extending in the vertical direction and covering a range narrower than said predetermined range, and for generating a plurality of light detection signals, each corresponding to a quantity of the light received in each of said regions of said light receiving member;

means for selecting at least one of said plurality of regions based on said generated running condition signal;

means for switching a range of angles of the light incident on said light detecting means based on said selected at least one region;

control means, coupled to receive said light detection signals from said light detecting means, for;

(1) comparing a level of at least one of said light detection signals corresponding to a quantity of the light received in a predetermined region of said light receiving member with a predetermined level;

(2) discriminating a presence or absence of a preceding vehicle or an oncoming vehicle based on a distribution of a quantity of light received at said plurality of regions;

(3) selecting a high beam mode or a low beam mode as an illumination mode of the headlight of said vehicle based on results of said comparing and discriminating; and

(4) generating a control signal for commanding said selected high beam mode or low beam mode; and

illumination switching means for receiving said control signal from said control means and switching the illumination mode of said headlight to obtain said selected high beam mode or low beam mode;

wherein said first or second regions in said light receiving member being selected in accordance with the signal output from said speed sensor, whereby a range of angles of the light incident on said light detecting means is switched to the left or right direction based thereon.

4. An apparatus according to claim 3, wherein said first regions are selected so that a range of angles of the light incident on said light detecting means is increased in a horizontal direction when said running condition signal indicates that said vehicle is running at a high speed.

5. An apparatus according to claim 3, wherein said second regions are selected so that a range of angles of the light incident on said light detecting means is decreased in a horizontal direction when said running condition signal indicates that said vehicle is running at a low speed.

7. A computer-controlled apparatus for controlling a headlight of a vehicle comprising:

an inclination sensor for detecting an inclination with regard along a running direction of said vehicle and generating an inclination signal;

light detecting means for receiving a light impinging on a front end of the vehicle using a light receiving member divided into first regions extending in the horizontal direction and covering a predetermined range in the vertical direction and second regions extending in the horizontal direction and covering another predetermined range in the vertical direction, and for generating a plurality of light detection signals, each corresponding to a quantity of the light received in each of said regions of said light receiving member;

means for selecting one of said plurality of regions based on said inclination signal;

means for switching a range of angles of the light incident on said light detecting means;

control means, coupled to receive said light detection signals from said light detecting means for;

(1) comparing a level of at least one of said light detection signals corresponding to a quantity of the light received in a predetermined region of said light receiving member with a predetermined level;

(2) discriminating a presence or absence of a preceding vehicle or an oncoming vehicle based on a distribution of quantity of light received at said plurality of regions;

(3) selecting a high beam mode or low beam mode as an illumination mode of the headlight of said vehicle based on a result of said comparing and discriminating; and

(4) generating a control signal for commanding said selected high beam mode or low beam mode; and

illumination switching means for receiving said control signal from said control means and switching the illumination mode of said headlight to obtain said selected high beam mode or low beam mode;

wherein said first or second regions in said light receiving member being selected in accordance with the signal output from said inclination sensor, whereby a range of angles of the light incident on said light detecting means is switched to the upper or lower direction based thereon.

8. An apparatus according to claim 7, wherein said first regions are selected so that a range of angles of the light incident on said light detecting means is directed to the lower direction when said inclination signal indicates that said vehicle is running on an upward slope or is accelerating.

9. An apparatus according to claim 7, wherein said second regions are selected so that a range of angles of the light incident on said light detecting means is directed to the upper direction when said inclination signal indicates that said vehicle is running on an downward slops or is decelerating.