Vehicle rear-view mirror and method of making same

• US 6,717,732 B2
• Filed: 08/22/2002
• Issued: 04/06/2004
• Est. Priority Date: 08/22/2001
• Status: Expired due to Fees

• Current Assignee: Helmut Piringer
• Original Assignee: Bayerische Motoren Werke AG, Helmut Piringer
• Inventors: Laux, Joseph, Meyr, Wolfgang, Piringer, Helmut
• Primary Examiner(s): Dunn, Drew
• Assistant Examiner(s): BOUTSIKARIS, LEONIDAS
• Application Number:
  US10/225,471
• Publication Number:
  US 20030058540A1
• Time in Patent Office: 593 Days
• Field of Search: 359/584, 359/589, 359/590, 359/884, 359/885, 359/577, 359/603, 359/614, 362/494, 362/510, 362/293, 362/135
• US Class Current: 359/584
• CPC Class Codes: B60R 1/083 Anti-glare mirrors, e.g. "day-night" mirrors
• CPC Class Codes: C03C 17/42 at least one coating of an organic material and at least one non-metal coating

Abstract

A vehicle rear-view mirror has a light-transmitting filtering layer for filtering out interfering fractions of the light entering the filtering layer in the yellow spectral range. The mirror includes an interference reflector which has a plurality of thin layers for the reflection of the light impinging on the mirror. The degree of reflection of the interference reflector is less in the yellow spectral range than in the green and/or red wavelength range.

Claims

1. Mirror, particularly a vehicle rear-view mirror, comprising:

a light-transmitting filtering layer for filtering out interfering fractions of light entering the filtering layer in the yellow spectral range, the filtering layer containing a substance distributed therein which causes an extinction of the interfering fractions, the filtering layer being arranged such that it is situated in the beam path of the light to be reflected which impinges on the mirror, and

an interference reflector having a plurality of thin layers for reflection of the light impinging on the mirror, the degree of reflection of the interference reflector in the yellow spectral range being lower than in an adjoining wavelength range with smaller wavelengths.

2. Mirror according to claim 1, wherein the interference reflector has a reflection degree maximum in a wavelength range of from 450 to 550 nm, and, starting from the maximum, the reflection degree decreases beyond the yellow spectral range.

3. Mirror according to claim 2, wherein the interference reflector has a reflecting degree maximum in a wavelength range of between 480 and 520 nm.

4. Mirror according to claim 1, wherein the interference reflector has three layers including a silicon oxide layer and two layers with a greater refractive index than the silicon oxide layer which embed the silicon oxide layer, and

wherein the three layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range is lower than in an adjoining wavelength range with smaller wavelengths.

5. Mirror according to claim 2, wherein the interference reflector has three layers including a silicon oxide layer and two layers with a greater refractive index than the silicon oxide layer which embed the silicon oxide layer, and

wherein the three layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range is lower than in an adjoining wavelength range with smaller wavelengths.

6. Mirror according to claim 3, wherein the interference reflector has three layers including a silicon oxide layer and two layers with a greater refractive index than the silicon oxide layer which embed the silicon oxide layer, and

wherein the three layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range is lower than in an adjoining wavelength range with smaller wavelengths.

7. Mirror according to claim 1, wherein the filtering layer has a layer thickness of less than 0.5 mm.

8. Mirror according to claim 7, wherein the filtering layer has a layer thickness in the range of from 0.25 to 0.35 mm.

9. Mirror according to claim 3, wherein the filtering layer has a layer thickness in the range of from 0.25 to 0.35 mm.

10. Mirror according to claim 4, wherein the filtering layer has a layer thickness in the range of from 0.25 to 0.35 mm.

11. Mirror according to claim 1, wherein the filtering layer consists of a silicone rubber in which the substance causing the extinction is distributed.

12. Mirror according to claim 3, wherein the filtering layer consists of a silicone rubber in which the substance causing the extinction is distributed.

13. Mirror according to claim 7, wherein the filtering layer consists of a silicone rubber in which the substance causing the extinction is distributed.

14. Mirror according to claim 4, wherein the filtering layer consists of a silicone rubber in which the substance causing the extinction is distributed.

15. Mirror according to claim 10, wherein the filtering layer consists of a silicone rubber in which the substance causing the extinction is distributed.

16. Mirror according to claim 1, wherein the mirror has an absorption layer for the absorption of light which has passed through the interference reflector, which absorption layer, in the visible wavelength range, has an average degree of reflection of less than 0.08.

17. Mirror according to claim 16, wherein the absorption layer has an average degree of reflection in the range of from 0.03 to 0.05.

18. Mirror according to claim 17, wherein the interference reflector has a reflection degree maximum in a wavelength range of from 450 to 550 nm, and, starting from the maximum, the reflection degree decreases beyond the yellow spectral range.

19. Mirror according to claim 17, wherein the interference reflector has three layers including a silicon oxide layer and two layers with a greater refractive index than the silicon oxide layer which embed the silicon oxide layer, and

wherein the three layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range is lower than in an adjoining wavelength range with smaller wavelengths.

20. Mirror according to claim 17, wherein the filtering layer has a layer thickness of less than 0.5 mm.

21. Mirror according to claim 1, wherein the mirror has an illumination device by which the mirror background can be illuminated, which mirror background is defined by a combination of the filtering layer and the interference reflector, so that light generated by the illumination device exits out of the mirror surface.

22. Mirror according to claim 16, wherein the mirror has an illumination device by which the mirror background can be illuminated, which mirror background is defined by a combination of the filtering layer and the interference reflector, so that light generated by the illumination device exits out of the mirror surface.

23. Mirror according to claim 21, wherein, viewed from the mirror surface, the light exit of the illumination device is arranged behind the absorption layer, and, in the visible wavelength range, the absorption layer has an average degree of transmission of more than 0.1.

24. Mirror according to claim 22, wherein, viewed from the mirror surface, the light exit of the illumination device is arranged behind the absorption layer, and, in the visible wavelength range, the absorption layer has an average degree of transmission of more than 0.1.

25. Mirror according to claim 21, wherein, viewed from the mirror surface, the light exit of the illumination device is arranged behind the absorption layer, and, in the visible wavelength range, the absorption layer has an average degree of transmission of more than 0.25.

26. Mirror according to claim 22, wherein, viewed from the mirror surface, the light exit of the illumination device is arranged behind the absorption layer, and, in the visible wavelength range, the absorption layer has an average degree of transmission of more than 0.25.

27. Method of producing a mirror, wherein a light-transmitting filtering layer, for filtering out interfering light fractions in the yellow spectral range, is combined with an interference reflector, wherein the interference reflector has a plurality of thin layers for the reflection of light, and wherein the thin layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range decreases with an increasing wavelength.

28. Method according to claim 27, wherein, for producing a filtering layer of the mirror, an optically effective substance is mixed with a silicone oil, the mixture is added to a first constituent used for the production of a multi-constituent silicone rubber, and the first constituent is combined with a second constituent used for producing the multi-constituent silicone rubber, so that a light-transmitting silicone rubber is formed with the optically effective substance distributed therein.

29. A mirror comprising:

a light transmitting filtering layer operable to filter out light in a yellow spectral range, and

an interference reflector formed of a plurality of layers and operable to reflect light impinging on the mirror with a degree of reflection in the yellow spectral range being lower than in adjoining smaller wavelengths.

30. A mirror according to claim 29,

wherein the interference reflector has a reflecting degree maximum in a wavelength range of between 480 and 520 nm

and wherein starting from the maximum, the reflection degree decreases beyond the yellow spectral range.

31. A mirror according to claim 29, wherein the interference reflector has three layers including a silicon oxide layer and two layers with a greater refractive index than the silicon oxide layer which embed the silicon oxide layer, and

wherein the three layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range is lower than in an adjoining wavelength range with smaller wavelengths.

32. A mirror according to claim 30, wherein the interference reflector has three layers including a silicon oxide layer and two layers with a greater refractive index than the silicon oxide layer which embed the silicon oxide layer, and

wherein the three layers are selected and mutually coordinated such that the degree of reflection of the interference reflector in the yellow spectral range is lower than in an adjoining wavelength range with smaller wavelengths.

33. A mirror according to claim 29, wherein the mirror has an absorption layer for the absorption of light which has passed through the interference reflector, which absorption layer, in the visible wavelength range, has an average degree of reflection of less than 0.08.

34. A method of making a mirror according to claim 29, comprising adhesively bonding said plurality of layers to one another.