IMAGE PICKUP DEVICE-EQUIPPED REAR-VIEW MIRROR

• US 20090040778A1
• Filed: 04/30/2008
• Published: 02/12/2009
• Est. Priority Date: 08/07/2007
• Status: Active Grant

• Current Assignee: Murakami Corporation
• Original Assignee: Murakami Corporation
• Inventors: TAKAYANAGI, Shinya, NAKAMURA, Masatoshi
• Granted Patent: US 8,308,325 B2
• Time in Patent Office: Days
• US Class Current: 362/494
• CPC Class Codes: B60R 1/00 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 Class Codes: B60R 1/12 Mirror assemblies combined with other articles, e.g. clocks
• CPC Class Codes: B60R 1/26 to the rear of the vehicle
• CPC Class Codes: B60R 1/30 providing vision in the non-visible spectrum, e.g. night or infrared vision
• CPC Class Codes: B60R 2001/1253 with cameras, video cameras or video screens
• CPC Class Codes: B60R 2300/106 using night vision cameras
• CPC Class Codes: B60R 2300/8053 for bad weather conditions or night vision
• CPC Class Codes: B60R 2300/8066 for monitoring rearward traffic
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

The present invention is intended to provide an image pickup device-equipped rear view mirror with improved image pickup performance, glare prevention and appearance (design) in addition to improved performance as a vehicle mirror. A mirror element is formed by forming a reflecting film consisting of high refractive index material films and a low refractive index material film on a back surface of a transparent glass substrate. The integrating sphere reflectance of the mirror element in the visible range is 40% to 60% and the near-infrared transmittance is no less than 70% for the whole or part of the band belonging to the near-infrared range within the entire sensitive wavelength range of the near-infrared camera. A black mask member is attached to an entire back surface of the reflecting film. The near-infrared camera is arranged behind the black mask member. The region corresponding to the area for the image-pickup by the near-infrared camera within the entire region of the black mask member is formed of a visible-light absorption and near-infrared transmission filter. The near-infrared transmittance of the visible-light absorption and near-infrared transmission filter is no less than 70% for the whole or part of the band belonging to the near-infrared range within the entire sensitive wavelength range of the near-infrared camera.

Claims

1. An image pickup device-equipped rear-view mirror, comprising:

a mirror element;

a dark color mask member arranged behind the mirror element; and

a near-infrared camera arranged behind the dark color mask member, an optical axis of the near-infrared camera being directed to a surface of the mirror element via the dark color mask member, wherein;

the mirror element has an integrating sphere reflectance of 40% to 60% in the visible range, and a near-infrared transmittance of no less than 70% for a whole or part of a band belonging to a near-infrared range within an entire sensitive wavelength range of the near-infrared camera;

a near-infrared transmittance of at least a region of the dark color mask member where the near-infrared camera is arranged is no less than 70% for a whole or part of a band belonging to a near-infrared range within the entire sensitive wavelength range of the near-infrared camera; and

the band for which the near-infrared transmittance of the mirror element is no less than 70%, and the band for which the near-infrared transmittance of the dark color mask member is no less than 70% have a band where they overlap each other.

2. The image pickup device-equipped rear-view mirror according to claim 1, wherein the at least a region of the dark color mask member where the near-infrared camera is arranged is formed of a visible-light absorption and near-infrared transmission filter attached to a back surface of the mirror element.

3. The image pickup device-equipped rear-view mirror according to claim 1, further comprising a near-infrared lamp arranged behind the dark color mask member, wherein

near-infrared light emitted from the near-infrared lamp is transmitted through the region of the dark color mask member with a near-infrared transmittance of no less than 70% and the mirror element, and released from a front surface of the mirror element.

4. The image pickup device-equipped rear-view mirror according to claim 2, further comprising a near-infrared lamp arranged behind the dark color mask member, wherein

near-infrared light emitted from the near-infrared lamp is transmitted through the region of the dark color mask member with a near-infrared transmittance of no less than 70% and the mirror element, and released from a front surface of the mirror element.

5. The image pickup device-equipped rear-view mirror according to claim 1, wherein a visible-range reflection peak wavelength of the mirror element is 500 nm to 550 nm.

6. The image pickup device-equipped rear-view mirror according to claim 2, wherein a visible-range reflection peak wavelength of the mirror element is 500 nm to 550 nm.

7. The image pickup device-equipped rear-view mirror according to claim 3, wherein a visible-range reflection peak wavelength of the mirror element is 500 nm to 550 nm.

8. The image pickup device-equipped rear-view mirror according to claim 4, wherein a visible-range reflection peak wavelength of the mirror element is 500 nm to 550 nm.

9. The image pickup device-equipped rear-view mirror according to claim 1, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

10. The image pickup device-equipped rear-view mirror according to claim 2, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

11. The image pickup device-equipped rear-view mirror according to claim 3, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

12. The image pickup device-equipped rear-view mirror according to claim 4, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

13. The image pickup device-equipped rear-view mirror according to claim 5, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

14. The image pickup device-equipped rear-view mirror according to claim 6, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

15. The image pickup device-equipped rear-view mirror according to claim 7, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

16. The image pickup device-equipped rear-view mirror according to claim 8, wherein a reflecting film of the mirror element is formed of a laminated film including a high refractive index material film and a low refractive index material film.

17. The image pickup device-equipped rear-view mirror according to claim 9, wherein the high refractive index material film is a TiO₂ film, the low refractive index material film is an SiO₂ film, and the number of deposited layers is three or four.

18. The image pickup device-equipped rear-view mirror according to claim 1, wherein a hydrophilic functional layer containing a photocatalytic substance is formed on the front surface of the mirror element.

19. The image pickup device-equipped rear-view mirror according to claim 1, wherein a laminated film including a photocatalytic layer and a hydrophilic layer is formed on the front surface of the mirror element.

20. An image pickup device-equipped rear-view mirror, comprising:

a mirror element with a reflecting film formed on a surface of a substrate formed of a dark color mask member; and

a near-infrared camera arranged behind the mirror element, an optical axis of the near-infrared camera being directed to a surface of the mirror element, wherein;

the reflecting film has an integrating sphere reflectance of 40% to 60% in the visible range and a near-infrared transmittance of no less than 70% for a whole or part of a band belonging to a near-infrared range within an entire sensitive wavelength range of the near-infrared camera;

a near-infrared transmittance of at least a region of the substrate where the near-infrared camera is arranged is no less than 70% for a whole or part of a band belonging to a near-infrared range within the entire sensitive wavelength range of the near-infrared camera; and

the band for which the near-infrared transmittance of the reflecting film is no less than 70%, and the band for which the near-infrared transmittance of the substrate is no less than 70% have a band where they overlap each other.