Face image taking device

• US 5,801,763 A
• Filed: 12/20/1995
• Issued: 09/01/1998
• Est. Priority Date: 07/06/1995
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Suzuki, Hiroyoshi
• Primary Examiner(s): BRITTON, HOWARD W
• Application Number:
  US08/575,487
• Time in Patent Office: 986 Days
• Field of Search: 348/15, 348/77, 348/409, 348/439, 382/103, 382/118, 382/128, 340/439, 340/575, 340/576
• US Class Current: 348/77
• CPC Class Codes: A61B 5/1176 Recognition of faces
• CPC Class Codes: G06V 20/597 Recognising the driver's state or behaviour, e.g. attention or drowsiness
• CPC Class Codes: G06V 40/19 Sensors therefor
• CPC Class Codes: G06V 40/193 Preprocessing; Feature extraction

Abstract

A face image taking device including a two-dimensional image taker for taking an image of a predetermined region including a face of a person to be detected; an optical filter having a pass band passing at least an infrared ray in a predetermined wavelength region and arranged on an optical axis of the two-dimensional image taking; an eye detector for detecting eyes of the person to be detected based on the image of the face of the person to be detected which has been taken by the two-dimensional image taker; an infrared ray illuminator for illuminating at least the face of the person to be detected by an infrared ray which has passed through the optical filter, said infrared ray illuminator being arranged such that an angle made by the optical axis of the two-dimensional image taker and an optical axis of the infrared ray is a predetermined angle or more; and an exciting means for exciting the infrared ray illuminator when the eye detector does not detect the eyes of the person to be detected.

Claims

1. A face image taking device comprising:

a two-dimensional image taking means for taking an image of a predetermined region including a face of a person to be detected;

an optical filter having a pass band passing at least an infrared ray in a predetermined wavelength region and arranged on an optical axis of the two-dimensional image taking means;

an eye detecting means for detecting eyes of the person to be detected based on the image of the face of the person to be detected which has been taken by the two-dimensional image taking means, said eye detecting means outputting a signal indicative of whether at least one eye has been detected;

an infrared ray illuminating means for illuminating at least the face of the person to be detected by an infrared ray which has passed through the optical filter, said infrared ray illuminating means being arranged such that an angle made by the optical axis of the two-dimensional image taking means and an optical axis of the infrared ray is a predetermined angle or more; and

an exciting means for exciting the infrared ray illuminating means based on said signal output by said eye detecting means indicating a failure to detect an eye of said person.

2. The face image taking device according to claim 1, wherein the exciting means stops the infrared ray illuminating means when a predetermined period of time has elapsed since the infrared ray illuminating means was excited.

3. The face image taking device according to claim 1, further comprising a spectacle detecting means for detecting presence or absence of spectacle worn by the person to be detected;

and

wherein the exciting means excites the infrared ray illuminating means in case where the spectacle detecting means detects spectacles and the eye detecting means does not detect the eyes of the person to be detected.

4. The face image taking device according to claim 1, wherein said signal is independent of the brightness in the vicinity of said person.

5. The face image taking device according to claim 1, further comprising a brightness/darkness detecting means for detecting either one of a bright state and a dark state at a surrounding of the person to be detected or at a vicinity of the face by detecting a brightness of the surrounding of the person to be detected or the vicinity of the face;

and

wherein the exciting means excites the infrared ray illuminating means in case where the brightness/darkness detecting means detects the bright state and the eye detecting means does not detect the eyes of the person to be detected.

6. The face image taking device according to claim 5, wherein the brightness/darkness detecting means determines either one of the bright state and the dark state based on whether a brightness of an image including the face of the person to be detected which has been taken by the two-dimensional image taking means is a predetermined brightness or more.

7. The face image taking device according to claim 5, further comprising a second infrared ray illuminating means for the dark state for illuminating the face of the person to be detected by an infrared ray which has passed through the optical filter when the brightness/darkness detecting means detects the dark state, said second infrared ray illuminating means for the dark state being provided separately from the infrared ray illuminating means excited when the eye detecting means does not detect the eyes of the person to be detected.

8. A face image taking device comprising:

a two-dimensional image taking means for taking an image of a predetermined region including a face of a person to be detected; and

an optical filter having a first pass band passing a visible light in a predetermined wavelength range and a second pass band passing an infrared ray having a predetermined wavelength or more and arranged on an optical axis of the two-dimensional image taking means.

9. The face image taking device according to claim 8, wherein the second pass band of the optical filter passes only an infrared ray in a predetermined wavelength range.

11. The face image taking device according to claim 8, further comprising a first optical filter having a first pass band and a second optical filter having a second pass band both constituting the optical filter;

a brightness/darkness detecting means for detecting either one of a bright state and a dark state at a surrounding of the person to be detected or at a vicinity of the face by detecting a brightness of the surrounding of the person to be detected or the vicinity of the face; and

a filter interchanging means for disposing the first optical filter on an optical axis of the two-dimensional image taking means when the brightness/darkness detecting means detects the bright state and disposing the second optical filter on the optical axis of the two-dimensional image taking means when the brightness/darkness detecting means detects the dark state.

10. A face image taking device comprising:

a two-dimensional image taking means for taking an image of a predetermined region including a face of a person to be detected;

an optical filter having a first pass band passing a visible light in a predetermined wavelength range and a second pass band passing an infrared ray having a predetermined wavelength or more and arranged on an optical axis of the two-dimensional image taking means;

an eye detecting means for detecting eyes of a person to be detected based on an image of the face of the person to be detected which has been taken by the two-dimensional image taking means, said eye detecting means outputting a signal indicative of whether at least one eye has been detected;

an infrared ray illuminating means for illuminating at least the face of the person to be detected by an infrared ray which has passed through the optical filter, said infrared ray illuminating means being arranged such that an angle made by an optical axis of the two-dimensional image taking means and an optical axis of the infrared ray is a predetermined angle or more; and

an exciting means for exciting the infrared ray illuminating means based on said signal output by said eye detecting means indicating a failure to detect an eye of said person.

12. The face image taking device according to claim 10, further comprising a first optical filter having a first pass band and a second optical filter having a second pass band both constituting the optical filter;

a brightness/darkness detecting means for detecting either one of a bright state and a dark state at a surrounding of the person to be detected or at a vicinity of the face by detecting a brightness of the surrounding of the person to be detected or the vicinity of the face; and

a filter interchanging means for disposing the first optical filter on an optical axis of the two-dimensional image taking means when the brightness/darkness detecting means detects the bright state and disposing the second optical filter on the optical axis of the two-dimensional image taking means when the brightness/darkness detecting means detects the dark state.

13. A face image taking device comprising:

a two-dimensional image receiver operable to receive an image of a predetermined region including a face of a person to be detected;

an optical filter having a pass band passing at least an infrared ray in a predetermined wavelength region and arranged on an optical axis of the two-dimensional image receiver;

an eye detector operable to detect an eye of the person to be detected based on the image of the face of the person to be detected which has been taken by the two-dimensional image receiver, said eye detector outputting a signal to said image taking device indicative of whether at least one eye has been detected, said signal based at least in part on information besides the brightness of the area in the vicinity of said person;

an infrared ray illuminator operable to illuminate the face of the person to be detected by an infrared ray which has passed through the optical filter, said infrared ray illuminator being arranged such that an angle made by the optical axis of the two-dimensional image receiver and an optical axis of the infrared ray is a predetermined angle or more; and

an exciter operable to excite the infrared ray illuminator based on said signal output by said eye detector indicating a failure to detect an eye of the person to be detected.

14. The face image taking device according to claim 13, wherein the exciter once stops the infrared ray illuminator when a predetermined period of time has elapsed since the infrared ray illuminator was excited.

15. The face image taking device according to claim 13, further comprising a spectacle detector operable to detect the presence or absence of a spectacle worn by the person to be detected;

and

wherein the exciter excites the infrared ray illuminator if the spectacle detector detects spectacles and the eye detector does not detect the eyes of the person to be detected.

16. The face image taking device according to claim 13, wherein said signal is independent of the brightness in the vicinity of said person.

17. The face image taking device according to claim 13, further comprising a brightness/darkness detector operable to detect either one of a bright state and a dark state at a surrounding of the person to be detected or at a vicinity of the face by detecting a brightness of the surrounding of the person to be detected or the vicinity of the face;

and

wherein the exciter excites the infrared ray illuminator if the brightness/darkness detector detects the bright state and the eye detector does not detect an eye of the person to be detected.

18. The face image taking device according to claim 17, wherein the brightness/darkness detector determines either one of the bright state and the dark state based on whether a brightness of an image including the face of the person to be detected which has been taken by the two-dimensional image receiver is a predetermined brightness or more.

19. The face image taking device according to claim 13, further comprising a second infrared ray illuminator operable to illuminate the face of the person to be detected in the dark state by an infrared ray which has passed through the optical filter when the brightness/darkness detector detects the dark state, said second infrared ray illuminator being provided separately from the infrared ray illuminator excited when the eye detector does not detect the eyes of the person to be detected.

20. A face image taking device comprising:

a two-dimensional image receiver operable to receive an image of a predetermined region including a face of a person to be detected; and

an optical filter having a first pass band passing a visible light in a predetermined wavelength range and a second pass band passing an infrared ray having a predetermined wavelength or more and arranged on an optical axis of the two-dimensional image receiver.

21. The face image taking device according to claim 20, wherein the second pass band of the optical filter passes only an infrared ray in a predetermined wavelength range.

22. The face image taking device according to claim 20, further comprising a first optical filter having a first pass band and a second optical filter having a second pass band both constituting the optical filter;

a brightness/darkness detector operable to detect either one of a bright state and a dark state at a surrounding of the person to be detected or at a vicinity of the face by detecting a brightness of the surrounding of the person to be detected or the vicinity of the face; and

a filter interchanger operable to dispose the first optical filter on an optical axis of the two-dimensional image receiver when the brightness/darkness detector detects the bright state and disposing the second optical filter on the optical axis of the two-dimensional image receiver when the brightness/darkness detector detects the dark state.

23. A face image taking device comprising:

a two-dimensional image receiver operable to receive an image of a predetermined region including a face of a person to be detected;

an optical filter having a first pass band passing a visible light in a predetermined wavelength range and a second pass band passing an infrared ray having a predetermined wavelength or more and arranged on an optical axis of the two-dimensional image receiver;

an eye detector operable to detect an eye of a person to be detected based on an image of the face of the person to be detected which has been taken by the two-dimensional image receiver, said eye detector outputting a signal indicative of whether at least one eye has been detected, said signal based at least in part on information besides the brightness of the area in the vicinity of said person;

an infrared ray illuminator operable to illuminate the face of the person to be detected by an infrared ray which has passed through the optical filter, said infrared ray illuminator being arranged such that an angle made by an optical axis of the two-dimensional image receiver and an optical axis of the infrared ray is a predetermined angle or more; and

an exciter operable to excite the infrared ray illuminator based on said signal output by said eye detector indicating a failure to detect an eye of the person to be detected.

24. The face image taking device according to claim 23, further comprising a first optical filter having a first pass band and a second optical filter having a second pass band both constituting the optical filter;

a brightness/darkness detector operable to detect either one of a bright state and a dark state at a surrounding of the person to be detected or at a vicinity of the face by detecting a brightness of the surrounding of the person to be detected or the vicinity of the face; and

a filter interchanger operable to dispose the first optical filter on an optical axis of the two-dimensional image receiver when the brightness/darkness detector detects the bright state and dispose the second optical filter on the optical axis of the two-dimensional image receiver when the brightness/darkness detector detects the dark state.