US 7,004,593 · Granted 2006-02-28
The Backlit Compass Mirror That Knew Which Way You Were Headed
Imagine a rearview mirror that doesn't just show you what's behind your car—it also tells you which direction you're driving using a built-in compass. This patent describes a mirror with tiny holes and lights behind them that light up to display compass directions, so drivers can check their heading without taking their eyes off the road.
The plain-English version
What it protects
The claim covers a rearview mirror system that combines a reflective mirror element with a compass display. What's protected here is the specific design of using small ports (holes) punched through the reflective coating, with illumination sources positioned behind those ports that can be individually controlled by a microprocessor to backlight each port independently. The system may also integrate GPS technology for determining vehicle direction, and the arrangement allows compass heading information to be displayed through the mirror's surface itself rather than on a separate screen.
Why it matters
This patent represents an early attempt to integrate heads-up information directly into existing vehicle components rather than adding separate dashboard displays. By embedding a compass into the rearview mirror, the design reduces driver distraction and uses existing mirror real estate efficiently. The approach of using backlit ports for display was an innovative way to show directional information before large head-up displays became common in vehicles, making it a notable entry point for smart mirrors in automotive design.
Real-world use
A driver glancing in the rearview mirror to check traffic behind them can simultaneously see which direction the vehicle is pointing without looking away or checking a separate compass dial.
Original USPTO abstract
An interior rearview mirror system includes a compass system and a display. The compass system is operable to display information indicative of a directional heading of the vehicle to a driver of the vehicle. The display comprises a plurality of ports formed in a reflective coating of a mirror reflective element and includes illumination sources positioned behind and generally aligned with corresponding ones of the ports. Each of the illumination sources may be energized to project illumination through a respective one of the ports such that the ports are backlit by the respective illumination sources, in order to convey the directional information to the driver of the vehicle. The system may include a microprocessor operable to control each illumination source via a respective wire connected between the microprocessor and each illumination source. The compass system may utilize a global positioning system for vehicle direction determination.
Patent details
- Publication number
- US 7,004,593
- Filing date
- 2003-06-06
- Grant date
- 2006-02-28
- Assignee
- Donnelly Corporation
- Inventor(s)
- WELLER ANDREW D., BLANK RODNEY K., SCHIERBEEK KENNETH L., SCHOFIELD KENNETH, LYNAM NIALL R., COOPRIDER TROY O.
- CPC class
- B60R1/12
Want to file your own patent?
Curious about what other automotive tech might be patented? Search our free database to see how many innovations are hiding in plain sight on today's cars.
Free patentability scan