Automatic dimming mirror using semiconductor light sensor with integral charge collection
First Claim
1. A rearview mirror for an automotive vehicle allowing a vehicle operator to view a scene generally behind the vehicle operator, the mirror comprising a dimming element having a variably reflective surface, the degree of reflectivity based on signals from an ambient light sensor positioned to receive light from a region generally in front of the vehicle and from a glare sensor positioned to view the scene generally behind the vehicle operator, wherein at least one of the ambient light sensor and the glare sensor accumulates charge in response to incident light over a predetermined integration period.
0 Assignments
0 Petitions
Accused Products
Abstract
An automatically dimming mirror includes a dimming element having variable reflectivity, the degree of reflectivity based on a control signal. An ambient light sensor is positioned to receive light from a region generally in front of the vehicle. The ambient light sensor outputs a discrete ambient light signal based on the amount of light incident on the ambient light sensor over an integration period. A glare sensor is positioned to view the scene generally behind the vehicle operator. The glare sensor outputs a discrete glare signal based on the amount of light incident on the glare sensor over an integration period. A dimming logic determines an ambient light level based on the ambient light signal. The glare integration period is determined based on the ambient light level. The glare signal resulting from the glare integration period determines a mirror glare level used to set the dimming element control signal.
7 Citations
20 Claims
- 1. A rearview mirror for an automotive vehicle allowing a vehicle operator to view a scene generally behind the vehicle operator, the mirror comprising a dimming element having a variably reflective surface, the degree of reflectivity based on signals from an ambient light sensor positioned to receive light from a region generally in front of the vehicle and from a glare sensor positioned to view the scene generally behind the vehicle operator, wherein at least one of the ambient light sensor and the glare sensor accumulates charge in response to incident light over a predetermined integration period.
- 9. A rearview mirror for an automotive vehicle allowing a vehicle operator to view a scene generally behind the vehicle operator, the mirror comprising a dimming element having a variably reflective surface, the degree of reflectivity based on signals from an ambient light sensor positioned to receive light from a region generally in front of the vehicle and from a glare sensor positioned to view the scene generally behind the vehicle operator, wherein at least one of the ambient light sensor and the glare sensor accumulates charge in response to incident light over a variable integration period.
-
11. A rearview mirror system for an automotive vehicle allowing a vehicle operator to view a scene generally behind the vehicle operator, the rearview mirror system including an interior rearview mirror, the interior rearview mirror comprising:
-
a dimming element having a variably reflective surface, the degree of reflectivity based on a dimming element control signal;
an ambient light sensor positioned to receive light from a region generally in front of the vehicle, the ambient light sensor operative to output a discrete ambient light signal based on the amount of light incident on the ambient light sensor over an ambient light integration period;
a glare sensor positioned to view the scene generally behind the vehicle operator, the glare sensor operative to output a discrete glare signal based on the amount of light incident on the glare sensor over a glare integration period; and
a dimming logic in communication with the dimming element, the ambient light sensor, and the glare sensor, the dimming logic operative to;
(a) determine an ambient light level based on the ambient light signal, (b) determine the glare integration period based on the determined ambient light level, (c) determine a mirror glare level based on the glare signal, (d) determine the dimming element control signal, and (e) output an ambient light signal based on the determined ambient light level. - View Dependent Claims (12, 13, 15, 16, 18, 19, 20)
-
-
14. A rearview mirror for an automotive vehicle allowing a vehicle operator to view a scene generally behind the vehicle operator, the mirror comprising:
-
a dimming element having a variably reflective surface, the degree of reflectivity based on a control signal;
a glare sensor positioned to view the scene generally behind the vehicle operator, the glare sensor operative to;
(a) receive an integration signal, (b) determine a glare signal based on the amount of light incident on the glare sensor over an interval based on the integration signal, (c) approximate the amount of thermal noise contained in the glare signal, the amount of thermal noise based on the glare sensor temperature, (d) remove the effect of the approximated thermal noise from the glare signal, and (e) output the glare signal a period of time after receiving the integration signal, the period of time based on the approximated amount of thermal noise; and
a dimming logic in communication with the dimming element and the glare sensor, the dimming logic operative to;
(a) determine an integration period, (b) generate the integration signal based on the determined integration period, (c) receive the glare signal after the period of time, (d) determine a mirror glare level based on the glare signal, (e) determine the dimming element control signal based on the mirror glare level, and (f) determine the glare sensor temperature based on the period of time.
-
-
17. A method for automatically dimming an automotive rearview mirror to reduce the effects of glare seen by a vehicle operator using the rearview mirror, the rearview mirror having an electrochromic element, an ambient light sensor, and a glare sensor, the electrochromic element providing a variable reflectivity based on a control signal, the ambient light sensor generating an ambient light signal based on light from a direction generally in front of the vehicle operator incident on the ambient light sensor over an ambient light integration period, the glare sensor generating a glare signal based on light from a direction generally behind the vehicle operator incident on the glare sensor over a glare integration period, the method comprising:
-
determining an ambient light level based on the ambient light signal;
determining the glare integration period based on the determined ambient light level;
determining a mirror glare level based on the glare signal; and
determining the electrochromic element control signal to adjust mirror reflectivity based on the determined mirror glare level, thereby reducing the effects of glare.
-
Specification