Vision system

• US 7,423,821 B2
• Filed: 03/22/2007
• Issued: 09/09/2008
• Est. Priority Date: 03/24/2006
• Status: Active Grant

• Current Assignee: HL Klemove Corporation
• Original Assignee: Gentex Corporation
• Inventors: Stray, Joel A., Tuttle, Darin D., Bechtel, Jon H., Ockerse, Harold C., Reese, Spencer D.
• Primary Examiner(s): Spector; David N
• Application Number:
  US11/726,638
• Publication Number:
  US 20070221826A1
• Time in Patent Office: 537 Days
• Field of Search: 348/340, 359/793, 359/794, 359/795, 359/796, 359/797, 359/811
• US Class Current: 359/796
• CPC Class Codes: G02B 13/0025 having one lens only
• CPC Class Codes: G02B 13/006 at least one element being a compound optical element, e.g. cemented elements
• CPC Class Codes: G02B 13/0085 employing wafer level optics
• CPC Class Codes: G02B 3/005 arranged along a single direction only, e.g. lenticular sheets G02B3/0043 takes precedence
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers

Abstract

The present invention relates to improved optical structures, related manufacturing processes and assemblies incorporating the improved optical structures. In at least one embodiment accurate light source color information is provided throughout substantially the entire associated field of view.

Claims

1. An image acquisition system, comprising:

a lens structure configured to project an image on an image surface of an image sensor, said lens structure comprising a compound lens, said compound lens comprising at least a first and a second lens element each comprising at least one substantially non-planar lens surface, said first and second lens elements comprising different lens materials, said first lens element is further away from said image sensor than said second lens element, said first lens element comprising a material with a higher Abbe number than said second lens element, wherein a change in an index of refraction of said second lens element is greater than a change in an index of refraction of said first lens element over a given temperature range, wherein an index of refraction of said first lens element changes more quickly as a function of temperature than an index of refraction of the second lens element thereby reducing the change in focal length of said compound lens over said given temperature range.

2. An image acquisition system as in claim 1 said first lens element comprising acrylic.

3. An image acquisition system as in claim 1 said first lens element comprising cyclic olefin copolymer.

4. An image acquisition system as in claim 1 further comprising an aperture mask between said first lens element and said image sensor.

8. An image acquisition system as in claim 1 wherein a focal length of said second lens element is negative.

9. An image acquisition system as in claim 1 wherein said second lens element is in direct contact with said first lens element.

10. An image acquisition system as in claim 1 wherein said second lens element material is a glue.

11. An image acquisition system as in claim 1 wherein said second lens element material is an epoxy.

5. An image acquisition system, comprising:

a lens structure configured to project an image on an image surface of an image sensor, said lens structure comprising a compound lens, said compound lens comprising at least a first and a second lens element each comprising at least one substantially non-planar lens surface, said first and second lens elements comprising different lens materials, said first lens element is further away from said image sensor than said second lens element, said first lens element comprising a material with a higher Abbe number than said second lens element, wherein a change in an index of refraction of said second lens element is greater than a change in an index of refraction of said first lens element over a given temperature range, thereby reducing the change in focal length of said compound lens over said given temperature range; and

an aperture mask between said first lens element and said image sensor, wherein said aperture mask is printed on a surface of said first lens element closest to said image surface.

6. An image acquisition system, comprising:

a lens structure configured to project an image on an image surface of an image sensor, said lens structure comprising a compound lens, said compound lens comprising at least a first and a second lens element each comprising at least one substantially non-planar lens surface, said first and second lens elements comprising different lens materials, said first lens element is further away from said image sensor than said second lens element, said first lens element comprising a material with a higher Abbe number than said second lens element, wherein a change in an index of refraction of said second lens element is greater than a change in an index of refraction of said first lens element over a given temperature range, thereby reducing the change in focal length of said compound lens over said given temperature range;

wherein said first lens element comprises, a scene side convex surface and an image sensor side convex surface.

7. An image acquisition system, comprising:

a lens structure configured to project an image on an image surface of an image sensor, said lens structure comprising a compound lens, said compound lens comprising at least a first and a second lens element each comprising at least one substantially non-planar lens surface, said first and second lens elements comprising different lens materials, said first lens element is further away from said image sensor than said second lens element, said first lens element comprising a material with a higher Abbe number than said second lens element, wherein a change in an index of refraction of said second lens element is greater than a change in an index of refraction of said first lens element over a given temperature range, thereby reducing the change in focal length of said compound lens over said given temperature range;

wherein a thickness of said first lens element is greater than a scene side surface radius thereof.