Plastic lens system for vehicle imaging system

• US 20020048086A1
• Filed: 12/06/2001
• Published: 04/25/2002
• Est. Priority Date: 07/27/1999
• Status: Active Grant

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Donnelly Corporation (Magna International Incorporated)
• Inventors: Bos, Brent J.
• Granted Patent: US 6,757,109 B2
• Time in Patent Office: Days
• US Class Current: 359/566
• CPC Class Codes: B60R 2300/107 using stereoscopic cameras
• CPC Class Codes: B60R 2300/108 using 'non-standard' camera systems, e.g. camera sensor used for additional purposes i.a. rain sensor, camera sensor split in multiple image areas
• CPC Class Codes: B60R 2300/8006 for monitoring and displaying scenes of vehicle interior, e.g. for monitoring passengers or cargo
• CPC Class Codes: B60R 2300/802 for monitoring and displaying vehicle exterior blind spot views
• CPC Class Codes: B60R 2300/8066 for monitoring rearward traffic
• CPC Class Codes: G02B 13/04 Reversed telephoto objectives
• CPC Class Codes: G02B 27/0037 with diffracting elements G02B27/0056 takes precedence; holographic optical elements G02B5/32; zone systems G02B5/1876
• CPC Class Codes: G02B 27/4211 correcting chromatic aberrations G02B27/0056, G02B27/4222, G02B27/4227 take precedence
• CPC Class Codes: G02B 9/34 having four components only

Abstract

An optical or lens system for use with an imaging system of a vehicle includes a plurality of optical elements. The optical elements include less than five optical elements and, preferably, include four optical elements. Each of the optical elements is formed of a plastic material. At least two of the optical elements include a diffractive element. Preferably, a diffractive element is formed on an outer surface of two of the optical elements. The optical system provides and focuses a field of view of a targeted area of at least approximately 100 degrees to an imaging plane. The imaging plane is at an imaging sensor or camera or other imaging device operable to receive the image from the optical system. The optical system further includes an aperture stop between two of the optical elements.

Claims

1. An optical system for use with an imaging system of a vehicle, said optical system comprising:

a plurality of optical elements, said plurality of optical elements comprising less than five optical elements, each of said plurality of optical elements comprising a plastic material, at least two of said plurality of optical elements comprising a diffractive element, said optical system providing a field of view of at least approximately 100 degrees to an imaging plane.

2. The optical system of claim 1, wherein one surface of two of said plurality of optical elements includes a diffractive element.

3. The optical system of claim 1, wherein said optical system provides the field of view to a sensor of a vehicular imaging system positioned at said imaging plane, said sensor being operable to receive an image of the field of view from said optical system.

4. The optical system of claim 3, wherein said sensor comprises a component of at least one of a vehicular vision system for providing scenic information of an area exteriorly of a vehicle to an occupant of the vehicle, a rain sensor, a headlamp control, a backup camera, a stereo imaging system and an interior monitor camera.

5. The optical system of claim 1, wherein said plurality of optical elements comprises an outer optical element, an inner optical element and first and second intermediate optical elements positioned between said outer and inner optical elements, said inner optical element being at an end of said optical system toward said imaging plane.

6. The optical system of claim 5, wherein said outer optical element comprises a clear aperture diameter of less than approximately 15 mm.

7. The optical system of claim 6, wherein said outer optical element comprises an outer surface and an inner surface, said outer and inner surfaces being positively curved.

8. The optical system of claim 7, wherein said outer surface has a radius of curvature which is greater than a radius of curvature of said inner surface.

9. The optical system of claim 8, wherein said outer surface of said outer optical element has a radius of curvature of approximately 15 mm and said inner surface of said outer optical element has a radius of curvature in the range of approximately 2.8 to 3.8 mm.

10. The optical system of claim 7, wherein said first intermediate optical element is positioned adjacent said outer optical element and said second intermediate optical element is positioned between said first intermediate optical element and said inner optical element.

11. The optical system of claim 10, wherein said first intermediate optical element has an outer negatively curved surface and an inner positively curved surface, said outer negatively curved surface facing said inner surface of said outer optical element.

12. The optical system of claim 11, wherein said outer negatively curved surface has a radius of curvature of approximately −

23 mm and said inner positively curved surface of said first intermediate optical element has a radius of curvature of approximately 3.5 to 4.1 mm.

13. The optical system of claim 11, wherein said second intermediate optical element has an outer positively curved surface and an inner negatively curved surface, said outer positively curved surface of said second intermediate optical element facing said inner positively curved surface of said first intermediate optical element.

14. The optical system of claim 13, wherein said outer positively curved surface of said second intermediate optical element comprises a diffractive element.

15. The optical system of claim 13, wherein said outer positively curved surface of said second intermediate optical element has a radius of curvature in the range of approximately 7 to 8 mm and said inner negatively curved surface has a radius of curvature of approximately −

4.4 to −

5.4 mm.

16. The optical system of claim 13, wherein said inner optical element comprises an outer positively curved surface and an inner negatively curved surface.

17. The optical system of claim 16, wherein said second outer positively curved surface of said inner optical element comprises a diffractive element.

18. The optical system of claim 16, wherein said outer positively curved surface of said inner optical element has a radius of curvature in the range of approximately 7 to 8 mm and said inner negatively curved surface of said inner optical element has a radius of curvature of approximately −

9 mm.

19. The optical system of claim 5 further including an aperture stop.

20. The optical system of claim 19, wherein said aperture stop is positioned between said second intermediate optical element and said inner optical element.

21. The optical system of claim 5, wherein said diffractive element is formed on said at least two of said plurality of optical elements.

22. The optical system of claim 21, wherein said at least two of said plurality of optical elements comprise said second intermediate optical element and said inner optical element.

23. The optical system of claim 22, wherein said diffractive element is formed on outer surfaces of said second intermediate optical element and said inner optical element, said outer surfaces facing toward said outer optical element.

24. The optical system of claim 1, wherein said plurality of optical elements comprises four optical elements.

26. The optical system of claim 25, wherein said outer optical element comprise a clear aperture diameter of less than approximately 15 mm.

27. The optical system of claim 25 further including an aperture stop.

28. The optical system of claim 27, wherein said aperture stop is positioned between said second intermediate optical element and said inner optical element.

29. The optical system of claim 25, wherein said diffractive element is formed at a surface of said second intermediate optical element and at a surface of said inner optical element.

30. The optical system of claim 29, wherein said diffractive element is formed on outer surfaces of said second intermediate optical element and said inner optical element, said outer surfaces facing toward said outer optical element.

25. An optical system for use with an imaging system of a vehicle, said optical system comprising:

a plurality of optical elements comprising an outer optical element, an inner optical element and first and second intermediate optical elements positioned between said outer and inner optical elements, said outer optical element being positioned at an end of said optical system toward a targeted scene, said first intermediate optical element being positioned between said outer optical element and said second intermediate optical element, said second intermediate optical element being positioned between said first intermediate optical element and said inner optical element, said plurality of optical elements comprising less than five optical elements, each of said plurality of optical elements comprising a plastic material, at least two of said plurality of optical elements having a diffractive element formed at a surface thereof, said optical system providing a field of view of the targeted scene of at least approximately 100 degrees to an image plane at said inner optical element.