Image pickup device-equipped rear-view mirror
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.
1. An image pickup device-equipped rear-view mirror, comprising:
a mirror element, comprising a dielectric multilayer reflecting film formed on a rear surface of a substrate, the reflecting film consisting of three or four laminated layers, including at least one high refractive index material film layer and at least one low refractive index material film layer;
a dark color mask member arranged behind the mirror element such that the rear surface of the substrate faces the dark color mask member; 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 a visible wavelength range, and a near-infrared transmittance of no less than 70% in a near-infrared wavelength range within a 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% in a near-infrared wavelength range within a sensitive wavelength range of the near-infrared camera; and
the near-infrared wavelength range in which the mirror element has a near-infrared transmittance of no less than 70% overlaps with the near-infrared wavelength range in which the near-infrared transmittance of the region of the dark color mask member is no less than 70%.
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 the high refractive index material film is a TiO 2 film and the low refractive index material film is an SiO 2 film.
10. 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.
11. 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.
12. The image pickup device-equipped rear-view mirror according to claim 1 , wherein a first layer of the dielectric multilayer reflecting film, which is formed on the rear surface of the substrate, is formed of a high refractive index material film.
13. The image pickup device-equipped rear-view mirror according to claim 12 , wherein the first layer of the dielectric multilayer reflecting film comprises a TiO 2 film.