Automatic rearview mirror incorporating light pipe

• US 5,434,407 A
• Filed: 08/23/1993
• Issued: 07/18/1995
• Est. Priority Date: 08/23/1993
• Status: Expired due to Fees

• Current Assignee: Gentex Corporation
• Original Assignee: Gentex Corporation
• Inventors: Bauer, Frederick T., Bechtel, Jon H.
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): LE, QUE TAN
• Time in patent office: 694 Days
• Field of Search: 250/227.11, 250/206, 250/214 B, 250/214 D, 250/214 AL, 250/227.24, 359/601, 359/602, 359/603, 359/604, 359/742, 385/12, 385/143, 385/146
• US Class Current: 250/227.24
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors

Abstract

An improved automatic rearview mirror for automotive vehicles, the mirror incorporating a light pipe effective to direct light from a convenient location to a conveniently placed light sensor and effective to optimize the performance and economy of the mirror.

Claims

1. In a light sensing device, the combination including light sensing means effective to detect light and generate a corresponding electrical signal indicative of the light level, light directing means, and means mounting said light directing means in spaced relationship with respect to said light sensing means whereby light passing through said light directing means impinges on said light sensing means, said light directing means being in the form of a light pipe, one end of said light pipe defining a curvilinear lens.

2. In an automatic rearview mirror system for automotive vehicles, the combination including a variable reflectance member the reflectivity of which varies as a function of an electrical signal, light sensing means effective to sense light and generate a corresponding electrical signal indicative of the sensed light level, a light pipe, said light pipe having the capability of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a curvilinear lens, means mounting said light pipe adjacent said light sensing means whereby light emanating from said other end of said light pipe impinges upon said light sensing means, and means operable to change the reflectivity of said reflectance member as a function of an electrical signal generated by said light sensing means.

3. In an automatic rearview mirror system for automotive vehicles, the combination including a variable reflectance member the reflectivity of which varies as a function of an electrical signal, light sensing means effective to sense light and generate a corresponding electrical signal indicative of the sensed light level, a light pipe, said light pipe having the capability of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a concave lens, means mounting said light pipe adjacent said light sensing means whereby light emanating from said other end of said light pipe impinges upon said light sensing means, and means operable to change the reflectivity of said reflectance member as a function of an electrical signal generated by said light sensing means.

4. In an automatic rearview mirror system for automotive vehicles, the combination including a variable reflectance member the reflectivity of which varies as a function of an electrical signal, light sensing means effective to sense light and generate a corresponding electrical signal indicative of the sensed light level, a light pipe, said light pipe having the capability of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a convex lens means mounting said light pipe adjacent said light sensing means whereby light emanating from said other end of said light pipe impinges upon said light sensing means, and means operable to change the reflectivity of said reflectance member as a function of an electrical signal generated by said light sensing means.

5. In an automatic rearview mirror system for automotive vehicles, the combination including a variable reflectance member the reflectivity of which varies as a function of an electrical signal, light sensing means effective to sense light and generate a corresponding electrical signal indicative of the sensed light level, a light pipe, said light pipe having the capability of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a Fresnel lens, means mounting said light pipe adjacent said light sensing means whereby light emanating from said other end of said light pipe impinges upon said light sensing means, and means operable to change the reflectivity of said reflectance member as a function of an electrical signal generated by said light sensing means.

6. In a light sensing device, the combination including a housing having a front wall and defining a chamber, said front wall defining an opening communicating with said chamber, a base disposed within said chamber, light sensing means mounted on such base and effective to detect light and generate a corresponding electrical signal indicative of the light level, a light pipe, said light pipe being mounted in said chamber and extending between said opening in said front wall and said base, said light pipe being capable of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a curvilinear lens, said other end of said light pipe being disposed in confronting relationship with respect to said light sensing means.

7. In a light sensing device, the combination including a housing having a front wall and defining a chamber, said front wall defining an opening communicating with said chamber, a base disposed within said chamber, light sensing means mounted on such base and effective to detect light and generate a corresponding electrical signal indicative of the light level, a light pipe, said light pipe being mounted in said chamber and extending between said opening in said front wall and said base, said light pipe being capable of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a concave lens, said other end of said light pipe being disposed in confronting relationship with respect to said light sensing means.

8. In a light sensing device, the combination including a housing having a front wall and defining a chamber, said front wall defining an opening communicating with said chamber, a base disposed within said chamber, light sensing means mounted on such base and effective to detect light and generate a corresponding electrical signal indicative of the light level, a light pipe, said light pipe being mounted in said chamber and extending between said opening in said front wall and said base, said light pipe being capable of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a convex lens, said other end of said light pipe being disposed in confronting relationship with respect to said light sensing means.

9. In a light sensing device, the combination including a housing having a front wall and defining a chamber, said front wall defining an opening communicating with said chamber, a base disposed within said chamber, light sensing means mounted on such base and effective to detect light and generate a corresponding electrical signal indicative of the light level, a light pipe, said light pipe being mounted in said chamber and extending between said opening in said front wall and said base, said light pipe being capable of internally reflecting light impinging on one end thereof to the other end thereof, said one end of said light pipe defining a Fresnel lens, said other end of said light pipe being disposed in confronting relationship with respect to said light sensing means.