Imaging rain sensor illumination positioning system

• US 20020148987A1
• Filed: 04/16/2001
• Published: 10/17/2002
• Est. Priority Date: 04/16/2001
• Status: Active Grant

• Current Assignee: Valeo Electrical Systems Incorporated (Valeo SE)
• Original Assignee: Valeo Electrical Systems Incorporated (Valeo SE)
• Inventors: Hochstein, Peter A.
• Granted Patent: US 6,614,043 B2
• Time in Patent Office: Days
• US Class Current: 250/573
• CPC Class Codes: B60S 1/0822 characterized by the arrangement or type of detection means
• CPC Class Codes: B60S 1/0833 Optical rain sensor
• CPC Class Codes: B60S 1/0844 including a camera
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle

Abstract

A method and assembly for sensing moisture on the exterior surface of a sheet of glass (14) comprising the steps of emitting light rays from an illuminator (12) on an illuminator axis (I) intersecting the glass (14) at an illuminator angle of incidence I_θ to reflect the light rays on a reflection axis (R) at an angle (R_θ) of reflection to the glass (14) and capturing on an imaging axis (C) the reflected light rays including reflections of moisture (19) on the exterior surface of the glass (14). The method is characterized by isolating the reflection of moisture (19) from the direct reflection of the illuminator (12) to prevent the capture of the direct reflection of the illuminator (12). This can be accomplished by offsetting the imaging axis (C) from the reflection axis (R), or by stopping the direct reflection of the illuminator (12) from being captured, as with a beam stop (24).

Claims

1. A method for sensing moisture on the exterior surface of a sheet of glass (14) comprising the steps of;

emitting light rays from an illuminator (12) on an illuminator axis (I) intersecting the glass (14) at an illuminator angle of incidence to reflect the light rays on a reflection axis at an angle of reflection to the glass,

capturing on an imaging axis (C) the reflected light rays including reflections of moisture on the exterior surface of the glass,

said method characterized by isolating the reflection of moisture from the direct reflection of the illuminator (12) to prevent the capture of the direct reflection of the illuminator (12).

2. A method as set forth in claim 1 wherein the step of isolating the reflection is further defined as offsetting the imaging axis (C) from the reflection axis.

3. A method as set forth in claim 1 wherein the step of isolating the reflection is further defined as stopping the direct reflection of the illuminator (12) from being captured.

4. An assembly for sensing moisture on the exterior surface of a sheet of glass (14) comprising;

an illuminator (12) for emitting light rays on an illuminator axis (I) intersecting the glass (14) at an illuminator angle of incidence to reflect the light rays on a reflection axis at an angle of reflection to the glass,

a detector (18) for capturing on an imaging axis (C) the reflected light rays including reflections of moisture on the exterior surface of the glass,

said assembly characterized by a beam stop (24) for isolating the reflection of moisture from the direct reflection of the illuminator (12) to prevent the capture of the direct reflection of the illuminator (12) by the detector.

5. An assembly for sensing moisture on the exterior surface of a sheet of glass (14) comprising;

an illuminator (12) for emitting light rays on an illuminator axis (I) intersecting the glass (14) at an illuminator angle of incidence to reflect the light rays on a reflection axis (R) at an angle of reflection (R_Ø

) to the glass,

a detector (18) for capturing on an imaging axis (C) the reflected light rays including reflections of moisture on the exterior surface of the glass,

said assembly characterized by offsetting (Ø

) the imaging axis (C) from the reflection axis (R) for isolating the reflection of moisture from the direct reflection of the illuminator (12) to prevent the capture of the direct reflection of the illuminator (12).

6. An assembly for sensing moisture on the exterior surface of a sheet of glass (14) comprising;

an illuminator (12) for emitting light rays on an illuminator axis (I) intersecting the glass (14) at an illuminator angle of incidence (I) to reflect the light rays on a reflection axis (R)at an angle of reflection (R_Ø

) to the glass,

a detector (18) for capturing on an imaging axis (C) the reflected light rays including reflections of moisture (19) on the exterior surface of the glass (14),

a rearview mirror housing (26) adapted to be attached adjacent the glass (14) in a vehicle,

said assembly characterized by said illuminator (12) and said detector (18) being supported in said housing (26).

7. An assembly as set forth in claim 6 including a mirror (32) for reflecting the light from said illuminator (12) to the glass (14) for reflection to said detector (18).