ACTIVE BLINDSPOT/LANE DEPARTURE DETECTION MIRROR SYSTEM

• US 20100226027A1
• Filed: 03/04/2009
• Published: 09/09/2010
• Est. Priority Date: 03/04/2009
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Kohlstrand, Kelly M.
• Granted Patent: US 8,282,225 B2
• Time in Patent Office: Days
• US Class Current: 359/843
• CPC Class Codes: B60R 1/082 using a single wide field mirror or an association of rigidly connected mirrors
• CPC Class Codes: G02B 2027/0123 comprising devices increasing the field of view
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 5/30 Polarising elements light-modulating devices with active elements G02F1/00

Abstract

A system to polarize a reflective layer on a vehicle mirror to reveal a convex mirror to view objects in a vehicle blindspot and method of operating the same.

Claims

1. A vehicle mounted mirror system to automatically reflect light from a vehicle blind spot toward a driver, comprising:

a primary mirror having a first surface and a second surface, an electrically polarizable reflective coating on at least a portion of its first surface;

said polarizable reflective coating being reflective in a depolarized state and substantially clear when polarized by an electric current applied thereto;

a blind zone viewing convex mirror adjacent to said second surface and proximal to said polarizable coating portion of said first surface; and

a blind spot detection system electrically connected to the primary mirror and a power source adapted to automatically apply current to polarize said primary mirror first surface when an object is detected in a blind spot and change the reflectivity of the reflective polarizable coating on at least a portion of the primary mirror first surface and expose the concave mirror to reflect light from the blind spot to the vehicle driver to permit the driver to see the object in the blind spot;

said blind spot detection system discontinuing current to the primary mirror thereby depolarizing the mirror surface once an object has assed out of the blind spot.

2. The mirror system of claim 1, wherein said blind spot detection system utilizes radar, sonar or lidar to detect objects in the vehicle blind spot.

3. The mirror system of claim 1, wherein the convex mirror is smaller than said primary mirror and located off center from the primary mirror center.

4. The mirror system of claim 1, wherein said mirror is protected with an optically transparent hard layer.

5. The mirror of claim 4, wherein the transparent hard layer is plastic or glass.

6. The mirror of claim 1, wherein the polarizable layer is selected from a nematic, smectic and cholestric liquid crystal layer.

7. The mirror of claim 1, wherein said first layer is coated with an electrically conductive and optically transparent conductor to form electrodes.

8. The mirror of claim 1, wherein said first layer is coated with ITO, tin oxide, or other electrically conductive and optically transparent materials to form electrodes.

9. The mirror system of claim 1, wherein the primary mirror and the blind zone mirror are an integral structure.

10. A method to operate a mirror system to reflect light from a vehicle blind spot toward a driver, comprising:

detecting an object in a vehicle blind spot;

determining whether the detected object is keeping pace or gaining on said vehicle;

applying an electric current to a polarizable layer to polarize at least a portion of the layer to change reflectivity off the layer expose a convex mirror through which the operator may actually view objects in a vehicle blind spot and upon termination of application of electricity, the polarizable layer resumes reflectivity.