Vehicle headlamp control utilizing a light sensor having at least two light transducers

• US 7,361,875 B2
• Filed: 05/27/2004
• Issued: 04/22/2008
• Est. Priority Date: 01/25/1999
• Status: Expired due to Fees

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Steenwyk, Timothy E., Plangger, David L., Schmidt, David J., Fossum, Eric R., Bauer, Frederick T., Turnbull, Robert R., Stam, Joseph S., Bechtel, Jon H., Knapp, Robert C., Poe, G. Bruce, Nixon, Robert H.
• Primary Examiner(s): Luu; Thanh X
• Application Number:
  US10/855,124
• Publication Number:
  US 20050002103A1
• Time in Patent Office: 1,426 Days
• Field of Search: 250/208.1, 250/205, 315/82
• US Class Current: 250/208.1
• 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 2300/054 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 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/314 Ambient light
• CPC Class Codes: B60Q 2300/337 Tunnels or bridges
• CPC Class Codes: B60Q 2400/30 Daytime running lights [DRL], e.g. circuits or arrangements therefor
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: G01J 1/1626 Arrangements with two photodetectors, the signals of which are compared
• CPC Class Codes: G01J 1/46 using a capacitor

Abstract

Equipment on automotive vehicle is controlled by a system including at least one semiconductor light sensor having variable sensitivity to light. Each light sensor generates a light signal indicative of the intensity of light incident on the light sensor. Control logic varies the sensitivity of the light sensor and generates equipment control signals based on received light signals. Sensitivity of light sensors may be varied by changing the integration time for producing charge from light incident on light transducers, by selecting between light transducers of different sensitivity within the light sensor, by using a light transducer with a sensitivity that is a function of the amount of incident light, and the like. Controlled equipment includes devices such as automatically dimming rearview mirrors, headlamps, and moisture removal means.

Claims

1. A vehicular automatic exterior light control system comprising:

a non-imaging light sensor for sensing light levels, said light sensor comprising an integrated circuit comprising a first light transducer, a second light transducer, and another electronic component; and

a control circuit coupled to said light sensor for generating an exterior light control signal as a function of the light levels sensed by said light sensor,

wherein said light sensor further comprises a lens for redirecting light onto at least one of said light transducers, and wherein said light sensor farther comprises an infrared filter,

wherein said light sensor further comprises an encapsulant material disposed over said integrated circuit, wherein a surface of said encapsulant material defines said lens.

2. A vehicular automatic exterior light control system comprising:

a non-imaging light sensor for sensing light levels, said light sensor comprising a first light transducer, a second light transducer, and another electronic component that are all integrated within an integrated circuit; and

a control circuit coupled to said light sensor for generating an exterior light control signal as a function of the light levels sensed by said light sensor,

wherein said another electronic component is a light-to-pulse circuit for generating a pulse in response to light levels sensed by said first light transducer during each of a plurality of integration periods, wherein a length of each pulse indicates the light level incident on said first light transducer over an integration period.

3. The control system of claim 2, wherein said light sensor further comprises a filter for separating infrared radiation from visible radiation, wherein said second light transducer is not exposed to the same optical spectrum as said first light transducer.

4. The control system of claim 2, wherein at least one of said light transducers accumulates charge in proportion to light incident over an integration period.

5. The control system of claim 2, wherein the exterior light control signal generated by said control circuit activates and deactivates at least one exterior light.

6. The control system of claim 5, wherein the at least one exterior light comprises headlamps.