METHOD FOR THE CONTROL OF A REARVIEW MIRROR AND REARVIEW-MIRROR SYSTEM FOR IMPLEMENTING THE METHOD

• US 20070081251A1
• Filed: 09/29/2006
• Published: 04/12/2007
• Est. Priority Date: 09/29/2005
• Status: Active Grant

• Current Assignee: Flabeg Deutschland GmbH
• Original Assignee: Flabeg GmbH & Co. KG
• Inventors: Lange, Klaus, Hiemer, Stefan, Schiller, Matthias, Hoegerl, Klaus, Martensson, Bengt
• Granted Patent: US 7,967,455 B2
• Time in Patent Office: Days
• US Class Current: 359/604
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors

Abstract

A method for controlling a rearview mirror, in particular for motor vehicles, provided with a reflection part with variable reflectance, includes supplying a control unit assigned to the reflection part with a nominal value for the reflectance. To provide a nominal value which is particularly favorable for the respective driving situation, the nominal value is specified by taking into consideration a first characteristic value characteristic of the sensitivity which adjusts in the viewer'"'"'s eye due to the light situation, and/or a second characteristic value characteristic of the kind of ambient light.

Claims

1. A method for controlling a rearview mirror having a reflection part with a variable reflectance, the method comprising:

specifying a nominal value based on at least one of a first characteristic value characteristic of a sensitivity of a viewer'"'"'s eye which adjusts due to a light situation in the viewer'"'"'s eye, and a second characteristic value characteristic of a kind of ambient light; and

supplying a control unit assigned to the reflection part with the nominal value for the reflectance.

2. The method as recited in claim 1, wherein the rearview mirror is a motor vehicle rearview mirror.

3. The method as recited in claim 1, further comprising determining the light situation in the viewer'"'"'s eye based on an ambient light and a glaring light reflected by the rearview mirror and determining the first characteristic value based on the light situation.

4. The method as recited in claim 3, wherein the determining of the light situation is performed by evaluating a sum of a first measured value characteristic of a luminous intensity of the ambient light, and a second measured value characteristic of a luminous intensity of the glaring light, multiplied by a current reflectance of the rearview mirror.

5. The method as recited in claim 1, further comprising:

cyclically determining anew a further first characteristic value by modifying the first characteristic value using a correction value, wherein the correction value is determined as a function of a deviation of the sensitivity of the viewer'"'"'s eye as a consequence of the current light situation from the given first characteristic value;

and specifying anew the nominal value using the further first characteristic value.

6. The method as recited in claim 5, further comprising weighting the correction value using a quotient of a cycle time and a time constant.

7. The method as recited in claim 6, further comprising choosing the time constant as a function of the sensitivity of the viewer'"'"'s eye as a consequence of the current light situation.

8. The method as recited in claim 7, further comprising,

assigning a first value to the time constant if a glare of the eye is detected;

assigning a second value to the time constant if a mesopic vision state is detected; and

assigning a third value to the time constant if a state scotopic vision is detected.

9. The method as recited in claim 8, wherein the first value is smaller than the second value and the second value is smaller than the third value.

10. The method as recited in claim 5, wherein the cyclically determining anew of the first characteristic value is performed according to the following equation:

11. The method as recited in claim 1, further comprising determining the second characteristic value using a variance parameter characterizing fluctuations around a predetermined mean value for a luminous intensity of the ambient light.

12. The method as recited in claim 11, further comprising cyclically determining anew a further variance parameter by modifying the first variance parameter by a variance correction value, the variance correction value being a function of a deviation of a difference between the luminous intensity of the ambient light and a mean value of the luminous intensity of the ambient light from the variance parameter.

13. The method as recited in claim 12, wherein the cyclically determining anew of the further variance parameter is performed according to at least one of the following equations:

14. The method as recited in claim 11, further comprising specifying a minimum and a maximum value for the second characteristic value.

18. The method as recited in claim 11, further comprising specifying a minimum and a maximum value for the nominal value.

15. The method as recited in claim I 1, further comprising determining the second characteristic value using a monotonously ascending curve.

16. The method as recited in claim 15, wherein the curve is asymptotically limited.

17. The method as recited in claim 15, wherein the determining of the second characteristic value is performed according to the following equation:

19. A rearview-mirror system comprising:

a rearview mirror having a reflection part with a variable reflectance;

a control unit assigned to the reflection part; and

a check unit supplying the control unit with a nominal value for the reflectance, the check unit configured to determining the nominal value based on at least one of a first characteristic value characteristic of a sensitivity of a viewer'"'"'s eye which adjusts due to a light situation in the viewer'"'"'s eye, and a second characteristic value characteristic of a kind of ambient light.

20. The rearview mirror as recited in claim 19, wherein the rearview mirror is a motor vehicle rearview mirror.