Automotive lamp

• US 20040218400A1
• Filed: 04/15/2004
• Published: 11/04/2004
• Est. Priority Date: 10/31/2001
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Egashira, Ken
• Granted Patent: US 7,137,718 B2
• Time in Patent Office: Days
• US Class Current: 362/520
• CPC Class Codes: B60Q 1/2607 comprising at least two indicating lamps
• CPC Class Codes: F21S 43/255 Filters
• CPC Class Codes: F21S 43/26 Refractors, transparent cover plates, light guides or filters not provided in groups F21S43/235 - F21S43/255
• CPC Class Codes: F21S 43/31 Optical layout thereof
• CPC Class Codes: F21V 9/14 for producing polarised light

Abstract

An automotive lamp (20) which, under unlighting conditions, can achieve harmonized and uniform appearance with a color of body and others, windows, parts and others, in addition to satisfactory function as a lamp under lighting conditions. An automotive lamp provided with a lamp chamber (21) containing at least one light source (22) in an interior thereof and having a light-emitting opening (25), is constructed such that the light-emitting opening (25) of the lamp chamber (21) has attached thereto a lamp cover (10) which comprises a transparent cover body and a polarizing film (11) applied to an inner surface of the cover body, the polarizing film (11) having fine textured structures on a surface thereof. In addition, an automotive lamp which can achieve the highest ever appearance design quality and permits observation of a uniform surface appearance high in quality with the feeling of depth emphasized when the lamp is extinguished. An automotive lamp (20) comprising a lamp chamber (21) with a light source (22) arranged therein and having a light-emitting opening (25), wherein a transparent lamp cover (10) is mounted on the light-emitting opening of the lamp chamber, and the inner surface of the lamp cover includes a selective polarizing layer (11) formed, in a predetermined pattern, with structure portions having a finely textured structural surface and non-structure portions not having such a textured structure.

Claims

1. A vehicle lamp comprising:

a lamp chamber containing at least one light source in an interior thereof and having a light-emitting opening;

a lamp cover attached to said light-emitting opening, said lamp cover comprising a transparent cover body having a configuration and size capable of covering at least a light emission surface of said lamp; and

a polarizing film applied to an inner surface of said cover body, said polarizing film having fine textured structures on a surface thereof for changing color of the exterior of said lamp when it is in a lit condition compared to an unlit condition.

2. A vehicle lamp according to claim 1, wherein said textured structures are fine textured structures exhibiting special optical characteristics such that the exterior of said lamp changes color when it is in a lit condition compared to an unlit condition.

3. A vehicle lamp according to claim 1, wherein said textured structures are fine prisms and said polarizing film is a prism sheet such as that useful in a back light for a liquid crystal display panel.

4. A vehicle lamp according to claim 1, wherein said lamp further comprises a cover color such that light from said light source acquires a predetermined functional color when emitted through said lamp cover out of said lamp chamber, and the functional color and the cover color are different from each other.

5. A vehicle lamp according to claim 1, wherein said lamp further comprises a cover color, and said polarizing film is a prism sheet that prevents the recognition of the color of the light source under unlit conditions so that only the cover color can be seen under unlit conditions and a color difference can be seen under lit conditions.

6. A vehicle lamp according to claim 1, wherein said polarizing film transmits P polarized light and reflects S polarized light, and the reflected S polarized light is transmitted through said polarizing film after the polarization is removed from the light upon its multiple reflection.

7. A vehicle lamp according to claim 1, wherein said polarizing film is a prismatic-structured film and said fine textured structures are prismatic structures.

8. A vehicle lamp according to claim 1, wherein said polarizing film is a luminance increasing film.

9. A vehicle lamp according to claim 1, wherein said vehicle lamp further comprises a filter element between said light source and said lamp cover.

10. A vehicle lamp according to claim 1, wherein the color of said cover body and the color of the light outwardly emitted through said polarizing film from said light source are different.

11. A vehicle lamp according to claim 1, wherein said vehicle lamp is a separated chamber type lamp structure comprising at least two lamp chambers each having a light source, and the color of at least one lamp chamber is different under lit and unlit conditions.

12. A vehicle lamp according to claim 11, wherein said vehicle lamp is used as a rear combination lamp of at least two lamps, from the group consisting of a brake lamp, a tail lamp, a brake and tail lamp, a turn-signal lamp and a back-up lamp, are contained in an optional pattern and combination, with the color of one of said lamps being different than the color of another of said lamps under lit conditions.

13. A vehicle lamp according to claim 12, wherein said lamp includes a turn-signal lamp and a brake lamp, said turn signal lamp is the same color under lit and unlit conditions, and said brake lamp is a different color under lit and unlit conditions, with the color of said brake lamp being different than the color of said turn-signal lamp under lit conditions.

14. A vehicle lamp according to claim 13, wherein the color of said brake lamp is the same as the color of said turn-signal lamp under unlit conditions.

15. A vehicle lamp according to claim 1, wherein said polarizing film is a single polarizing layer.

16. A vehicle lamp according to claim 15, wherein said single polarizing layer is a single selective polarizing layer.

17. A vehicle lamp according to claim 16, wherein said single selective polarizing layer is formed, in a predetermined pattern, with structure portions of a finely textured structural surface and non-structure portions not having such a textured structural surface.

18. A vehicle lamp according to claim 17, wherein said textured structure of said structure portions is such that the pitch p of said prisms is not more than 1 mm and the apex angle α

of said prisms is not more than 150°

.

19. A vehicle lamp according to claim 17, wherein the inner surface of said lamp cover is formed with said selective polarizing layer by processing the patterns of said structure portions and said non-structure portions.

20. A vehicle lamp according to claim 17, wherein the transparency degree (defined as the area ratio between said structure portions and said non-structure portions) of said selective polarizing layer is in the range of 5 to 90%.

21. A vehicle lamp according to claim 17, wherein said structure portions or said non-structure portions of said selective polarizing layer are formed of a pattern of selected one of stripes, grids, dots and a combination thereof.

22. A vehicle lamp according to claim 1, wherein said lamp cover is colored.

23. A vehicle lamp according to claim 1, wherein said lamp cover has the function of a lens.

24. A vehicle lamp according to claim 1, wherein said textured structures are located on only one surface of said polarizing film.

25. A vehicle lamp according to claim 1, wherein said textured structures are located on only one surface of said polarizing film, which is facing toward said light source.

26. A vehicle lamp according to claim 1, wherein said textured structures are located on only one surface of said polarizing film, which is facing toward said lamp cover.

27. A vehicle lamp according to claim 1, wherein said textured structures are prism structures located on only one surface of said polarizing film.