Vehicle vision system with lens pollution detection

Patent metadata

Field	Value
Publication number	US-10021278-B2
Application number	US-201615131595-A
Country	US
Kind code	B2
Filing date	Apr 18, 2016
Priority date	Mar 27, 2012
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

A vision system for a vehicle includes a camera having an imaging array having multiple columns of photosensing elements and multiple rows of photosensing elements, with the columns of photosensing elements being generally vertically orientated and the rows of photosensing elements being generally horizontally orientated relative to ground. The multiple rows of photosensing elements comprising top rows, middle rows and bottom rows. When the vehicle is moving, top row brightness values at top rows, middle row brightness values at middle rows, and bottom row brightness values at bottom rows are determined by processing of captured image data by a processor. Contrast of middle row brightness values compared to bottom row brightness values or top row brightness values is determined and, based on determined contrast of middle row brightness values compared to bottom row brightness values or top row brightness values, an at least partial blockage of the camera is detected.

First claim

The invention claimed is:

1. A vision system for a vehicle, said vision system comprising:
a camera disposed at a vehicle and having a field of view exterior of the vehicle;
wherein said camera comprises a lens and an imaging array comprising an array of photosensing elements having multiple columns of photosensing elements and multiple rows of photosensing elements;
said multiple columns of photosensing elements being generally vertically orientated relative to ground when said camera is disposed at the vehicle;
said multiple rows of photosensing elements being generally horizontally orientated relative to ground when said camera is disposed at the vehicle;
said multiple rows of photosensing elements comprising top rows, middle rows and bottom rows;
wherein, with said camera disposed at the vehicle, top rows are higher above ground than middle and bottom rows;
wherein, with said camera disposed at the vehicle, middle rows are higher above ground than bottom rows and are lower above ground than top rows;
wherein, with said camera disposed at the vehicle, middle rows are between top rows and bottom rows;
a processor operable to process image data captured by said camera;
wherein, when the vehicle is moving, top row brightness values at top rows are determined by processing of captured image data by said processor;
wherein, when the vehicle is moving, middle row brightness values at middle rows are determined by processing of captured image data by said processor;
wherein, when the vehicle is moving, bottom row brightness values at bottom rows are determined by processing of captured image data by said processor;
wherein contrast of middle row brightness values compared to bottom row brightness values or top row brightness values is determined; and
wherein, based on determined contrast of middle row brightness values compared to bottom row brightness values or top row brightness values, an at least partial blockage of said camera is detected.

2. The vision system of claim 1 , wherein said processor is incorporated in circuitry of said camera.

3. The vision system of claim 1 , wherein said processor is incorporated in circuitry of a control of the vehicle.

4. The vision system of claim 1 , wherein said processor is operable to read a selected set of imager register values and compare a contrast of auto exposure control zones, and wherein, responsive to a determination that a range of contrast levels is less than a threshold level, said processor determines that there are contaminants at said lens of said camera.

5. The vision system of claim 4 , wherein said processor is operable to compare a contrast of auto exposure control zones when an auto exposure function of said camera is enabled.

6. The vision system of claim 4 , wherein said processor compares contrast levels between a generally middle zone and an upper or lower zone.

7. The vision system of claim 4 , wherein said processor is incorporated in circuitry of said camera.

8. The vision system of claim 1 , wherein the vehicle moving comprises the vehicle being driven forward on a road.

9. The vision system of claim 8 , wherein determining contrast of middle row brightness values compared to bottom row brightness values or top row brightness values comprises determining the difference of middle row brightness values to bottom row brightness values or top row brightness values in the same column compared to in a different column.

10. The vision system of claim 8 , wherein said processor is incorporated in circuitry of a control of the vehicle.

11. The vision system of claim 1 , wherein, when an at least partial blockage of said camera is detected, said system at least one of (i) generates an alert, (ii) adapts processing of captured image data to at least partially accommodate for the at least partial blockage and (iii) cleans said lens.

12. The vision system of claim 1 , wherein said camera comprises a CMOS camera.

13. The vision system of claim 12 , wherein said imaging array comprises at least 640 columns of photosensing elements and at least 480 rows of photosensing elements.

14. The vision system of claim 13 , wherein said camera is part of a multi-camera birds-eye surround view system of the equipped vehicle.

15. A vision system for a vehicle, said vision system comprising:
a camera disposed at a vehicle and having a field of view exterior of the vehicle;
wherein said camera comprises a lens and an imaging array comprising an array of photosensing elements having at least 640 columns of photosensing elements and at least 480 rows of photosensing elements;
said at least 640 columns of photosensing elements being generally vertically orientated relative to ground when said camera is disposed at the vehicle;
said at least 480 rows of photosensing elements being generally horizontally orientated relative to ground when said camera is disposed at the vehicle;
said at least 480 rows of photosensing elements comprising top rows, middle rows and bottom rows;
wherein, with said camera disposed at the vehicle, top rows are higher above ground than middle and bottom rows;
wherein, with said camera disposed at the vehicle, middle rows are higher above ground than bottom rows and are lower above ground than top rows;
wherein, with said camera disposed at the vehicle, middle rows are between top rows and bottom rows;
a processor operable to process image data captured by said camera;
wherein, when the vehicle is moving, top row brightness values at top rows are determined by processing of captured image data by said processor;
wherein, when the vehicle is moving, middle row brightness values at middle rows are determined by processing of captured image data by said processor;
wherein, when the vehicle is moving, bottom row brightness values at bottom rows are determined by processing of captured image data by said processor;
wherein contrast of middle row brightness values compared to bottom row brightness values or top row brightness values is determined;
wherein, based on determined contrast of middle row brightness values compared to bottom row brightness values or top row brightness values, an at least partial blockage of said camera is detected; and
wherein, when an at least partial blockage of said camera is detected, said system at least one of (i) generates an alert, (ii) adapts processing of captured image data to at least partially accommodate for the at least partial blockage and (iii) cleans said lens.

16. The vision system of claim 15 , wherein said processor is incorporated in circuitry of said camera.

17. The vision system of claim 15 , wherein said processor is incorporated in circuitry of a control of the vehicle.

18. A vision system for a vehicle, said vision system comprising:
a camera disposed at a vehicle and having a field of view exterior of the vehicle;
wherein said camera comprises a lens and an imaging array comprising an array of photosensing elements having at least 640 columns of photosensing elements and at least 480 rows of photosensing elements;
said at least 640 columns of photosensing elements being generally vertically orientated relative to ground when said camera is disposed at the vehicle;
said at least 480 rows of photosensing elements being generally horizontally orientated relative to ground when said camera is disposed at the vehicle;
said at least 480 rows of photosensing elements comprising top rows, middle rows and bottom rows;
wherein, with said camera disposed at the vehicle, top rows are higher above ground than middle and bott

Assignees

• Magna Electronics Inc

Inventors

• Lu Yuesheng
• Hunt Shawn T

Classifications

• H04N23/811 Primary

  by dust removal, e.g. from surfaces of the image sensor or processing of the image signal output by the electronic image sensor · CPC title

• B60R2300/30

  characterised by the type of image processing · CPC title

• H04N7/18

  Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast · CPC title

• B60R1/00

  Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles · CPC title

• H04N5/2171 Primary

  Electricity · mapped topic