Camera for vehicle vision system

• US 9,451,138 B2
• Filed: 11/07/2014
• Issued: 09/20/2016
• Est. Priority Date: 11/07/2013
• Status: Active Grant

• Current Assignee: Magna Electronics Incorporated (Magna International Incorporated)
• Original Assignee: Magna Electronics Incorporated (Magna International Incorporated)
• Inventors: Winden, Brian J., Devota, Robert A., Sesti, Matthew C., Stemmer, Joseph A., Byrne, Steven V., Garcia, John R., Olson, David F.
• Primary Examiner(s): WILLIAMS, JEFFERY A
• Application Number:
  US14/535,739
• Publication Number:
  US 20150124098A1
• Time in Patent Office: 683 Days
• Field of Search: 348/148
• US Class Current: 1/1
• CPC Class Codes: C09J 163/00 Adhesives based on epoxy resins; Adhesives based on derivatives of epoxy resins
• CPC Class Codes: C09J 2463/00 Presence of epoxy resin
• CPC Class Codes: C09J 5/00 Adhesive processes in general; Adhesive processes not provided for elsewhere, e.g. relating to primers
• CPC Class Codes: H04N 23/51 Housings
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof

Abstract

A vehicular camera includes a lens, a printed circuit board and an imager. The lens has a plurality of optical element and is disposed at a lens holder. The imager is disposed at the printed circuit board. The adhesive is initially curable in an initial radiation curing process that comprises exposure to UV light, and initially-cured adhesive is further curable to a further cured strength in a secondary thermal curing process. The adhesive is initially cured via the initial radiation curing process after the lens is brought into focus with the imager and is optically center-aligned therewith. The initially-cured adhesive, as cured via the initial radiation curing process, holds the lens optically center-aligned and in focus with the imager. After the initial radiation curing process, the lens holder, adhesively attached to one of the printed circuit board and the holding element, is moved to the secondary thermal curing process.

Claims

1. A vehicular camera suitable for use on a vehicle, said vehicular camera comprising:

a lens comprising a plurality of optical elements;

wherein said lens is disposed at a lens holder;

a printed circuit board;

an imager disposed at said printed circuit board;

wherein one of (i) said printed circuit board is held by a holding element and said lens holder is attached at said holding element by a cured adhesive and (ii) said lens holder is attached at said printed circuit board by a cured adhesive;

wherein the adhesive is initially curable in an initial radiation curing process that comprises exposure to UV light, and wherein initially-cured adhesive is further curable to a further cured strength in a secondary thermal curing process;

wherein the adhesive is initially cured via the initial radiation curing process after said lens is brought into focus with said imager and is optically center-aligned therewith;

wherein the initially-cured adhesive, as cured via the initial radiation curing process, holds said lens optically center-aligned and in focus with said imager;

wherein, after the initial radiation curing process, said lens holder, adhesively attached to one of said printed circuit board and said holding element, is moved to the secondary thermal curing process;

wherein, when further cured via the secondary thermal curing process, the further-cured adhesive maintains focus and optical center-alignment of said lens with said imager for use of said camera in a vehicle; and

wherein the adhesive comprises a UV curable and heat curable one-part filled adhesive having a viscosity at 23 degrees C. from about 5,000 mPa to about 150,000 mPa and comprising an epoxy resin.

2. The vehicular camera of claim 1, wherein said optical elements are disposed within a lens barrel and wherein said lens barrel is one of (i) attached at said lens holder and (ii) integral with said lens holder.

3. The vehicular camera of claim 1, wherein said optical elements are disposed within a lens barrel and wherein said lens barrel one of (i) threadedly attaches at said lens holder, (ii) adhesively attaches at said lens holder and (iii) threadedly and adhesively attaches at said lens holder.

4. The vehicular camera of claim 1, wherein said optical elements are disposed within a lens barrel and wherein said lens barrel is integrated into the lens holder such that they comprise a single or unitary element.

5. The vehicular camera of claim 1, comprising a camera housing portion joined to said lens holder, wherein said camera housing portion and said lens holder, when joined, substantially encase said printed circuit board, and wherein said camera housing portion comprises an electrical connector for electrically connecting circuitry at said printed circuit board to electrical wiring of the vehicle, and wherein said camera housing portion is joined to said lens holder via at least one of (i) ultrasonic welding, (ii) adhesive and (iii) press fitting.

6. The vehicular camera of claim 1, wherein said lens holder is attached at said printed circuit board by the cured adhesive, and wherein the further-cured adhesive maintains at least a minimum strength of bond between the lens holder and the printed circuit board after being exposed to at least one operating condition for a period of time, wherein the at least one operating condition includes a temperature of approximately 85 degrees Celsius, and wherein the at least one operating condition includes a humidity of approximately 85%, and wherein the period of time is greater than 1000 hours, and wherein the minimum strength of bond is approximately the same as the strength of the fully cured adhesive.

7. The vehicular camera of claim 1, wherein at least one of (a) a lens resolution of said lens is selected to meet but not substantially exceed a resolution determined from (i) the size of a display associated with said camera, (ii) a distance between an observer and the display, (iii) a selected point on a contrast sensitivity function and (iv) the size of the imager sensing surface, and (b) the lens omits achromatic lenses and employs digital chromatic correction based on a predetermined chromatic aberration measurement.

8. The vehicular camera of claim 1, wherein optical center-alignment and focusing of said lens relative to said imager is achieved robotically.

9. The vehicular camera of claim 1, wherein the adhesive comprises one of (i) a Delo OB749 adhesive, (ii) a Delo AD VE 112203 adhesive and (iii) a Delo OB787 adhesive.

10. The vehicular camera of claim 1, wherein said vehicular camera is configured for use as a rearward viewing camera of a vehicle.

11. A vehicular camera suitable for use on a vehicle, said vehicular camera comprising:

a lens comprising a plurality of optical elements;

wherein said lens is disposed at a lens holder;

a printed circuit board;

an imager disposed at said printed circuit board;

a camera housing portion joined to said lens holder, wherein said camera housing portion and said lens holder, when joined, substantially encase said printed circuit board, and wherein said camera housing portion comprises an electrical connector for electrically connecting circuitry at said printed circuit board to electrical wiring of the vehicle, and wherein said camera housing portion is joined to said lens holder via at least one of (i) ultrasonic welding, (ii) adhesive and (iii) press fitting;

wherein said lens holder is attached at said printed circuit board by a cured adhesive;

wherein the adhesive is initially curable in an initial radiation curing process that comprises exposure to UV light, and wherein initially-cured adhesive is further curable to a further cured strength in a secondary thermal curing process;

wherein the adhesive is initially cured via the initial radiation curing process after said lens is brought into focus with said imager and is optically center-aligned therewith;

wherein the initially-cured adhesive, as cured via the initial radiation curing process, holds said lens optically center-aligned and in focus with said imager;

wherein, after the initial radiation curing process, said lens holder, adhesively attached to one of said printed circuit board and said holding element, is moved to the secondary thermal curing process;

wherein, when further cured via the secondary thermal curing process, the further-cured adhesive maintains focus and optical center-alignment of said lens with said imager for use of said camera in a vehicle;

wherein the further-cured adhesive maintains at least a minimum strength of bond between the lens holder and the printed circuit board after being exposed to at least one operating condition for a period of time, wherein the at least one operating condition includes a temperature of approximately 85 degrees Celsius, and wherein the at least one operating condition includes a humidity of approximately 85%, and wherein the period of time is greater than 1000 hours, and wherein the minimum strength of bond is approximately the same as the strength of the fully cured adhesive; and

wherein the adhesive comprises a UV curable and heat curable one-part filled adhesive having a viscosity at 23 degrees C. from about 5,000 mPa to about 150,000 mPa and comprising an epoxy resin.

12. The vehicular camera of claim 11, wherein said optical elements are disposed within a lens barrel and wherein said lens barrel is one of (i) attached at said lens holder and (ii) integral with said lens holder.

13. The vehicular camera of claim 11, wherein said optical elements are disposed within a lens barrel and wherein said lens barrel one of (i) threadedly attaches at said lens holder, (ii) adhesively attaches at said lens holder and (iii) threadedly and adhesively attaches at said lens holder.

14. The vehicular camera of claim 11, wherein said optical elements are disposed within a lens barrel and wherein said lens barrel is integrated into the lens holder such that they comprise a single or unitary element.

15. The vehicular camera of claim 11, wherein a lens resolution of said lens is selected to meet but not substantially exceed a resolution determined from (i) the size of a display associated with said camera, (ii) a distance between an observer and the display, (iii) a selected point on a contrast sensitivity function and (iv) the size of the imager sensing surface.

16. The vehicular camera of claim 11, wherein the adhesive comprises one of (i) a Delo OB749 adhesive, (ii) a Delo AD VE 112203 adhesive and (iii) a Delo OB787 adhesive.

17. The vehicular camera of claim 11, wherein optical center-alignment and focusing of said lens relative to said imager is achieved robotically.

18. A vehicular camera suitable for use on a vehicle, said vehicular camera comprising:

a lens comprising a plurality of optical elements;

wherein said optical elements of said lens are disposed within a lens barrel and wherein said lens barrel is one of (i) attached at a lens holder and (ii) integral with a lens holder;

a printed circuit board;

an imager disposed at said printed circuit board;

a camera housing portion joined to said lens holder, wherein said camera housing portion and said lens holder, when joined, substantially encase said printed circuit board, and wherein said camera housing portion comprises an electrical connector for electrically connecting circuitry at said printed circuit board to electrical wiring of the vehicle;

wherein one of (i) said printed circuit board is held by a holding element and said lens holder is attached at said holding element by a cured adhesive and (ii) said lens holder is attached at said printed circuit board by a cured adhesive;

wherein the adhesive is initially curable in an initial radiation curing process that comprises exposure to UV light, and wherein initially-cured adhesive is further curable to a further cured strength in a secondary thermal curing process;

wherein the adhesive is initially cured via the initial radiation curing process after said lens is brought into focus with said imager and is optically center-aligned therewith;

wherein optical center-alignment and focusing of said lens relative to said imager is achieved robotically;

wherein the initially-cured adhesive, as cured via the initial radiation curing process, holds said lens optically center-aligned and in focus with said imager;

wherein, after the initial radiation curing process, said lens holder, adhesively attached to one of said printed circuit board and said holding element, is moved to the secondary thermal curing process;

wherein, when further cured via the secondary thermal curing process, the further-cured adhesive maintains focus and optical center-alignment of said lens with said imager for use of said camera in a vehicle; and

wherein the adhesive comprises a UV curable and heat curable one-part filled adhesive having a viscosity at 23 degrees C. from about 5,000 mPa to about 150,000 mPa and comprising an epoxy resin.

19. The vehicular camera of claim 18, wherein the further-cured adhesive maintains at least a minimum strength of bond strength after being exposed to at least one operating condition for a period of time, wherein the at least one operating condition includes a temperature of approximately 85 degrees Celsius, and wherein the at least one operating condition includes a humidity of approximately 85%, and wherein the period of time is greater than 1000 hours, and wherein the minimum strength of bond is approximately the same as the strength of the fully cured adhesive.

20. The vehicular camera of claim 18, wherein at least one of (a) a lens resolution of said lens is selected to meet but not substantially exceed a resolution determined from (i) the size of a display associated with said camera, (ii) a distance between an observer and the display, (iii) a selected point on a contrast sensitivity function and (iv) the size of the imager sensing surface, and (b) the lens omits achromatic lenses and employs digital chromatic correction based on a predetermined chromatic aberration measurement.