IMAGE ACQUISITION DEVICE, BIOMETRIC AUTHENTICATION DEVICE, AND ELECTRONIC APPARATUS

• US 20120257031A1
• Filed: 04/02/2012
• Published: 10/11/2012
• Est. Priority Date: 04/07/2011
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: TSUCHIYA, Hitoshi, ISHIGURO, Hideto, EGUCHI, Tsukasa
• Granted Patent: US 9,379,157 B2
• Time in Patent Office: Days
• US Class Current: 348/77
• CPC Class Codes: G06V 40/1318 using electro-optical elements or layers, e.g. electroluminescent sensing
• CPC Class Codes: H01L 27/14618 Containers
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H01L 27/14627 Microlenses
• CPC Class Codes: H01L 27/14632 Wafer-level processed structures
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An image acquisition device includes: an imaging unit which has a plurality of light receiving elements; a condensing unit which condenses light which is input to the light receiving elements, and includes a plurality of microlenses which are arranged one to one with the light receiving elements on a plane; and a band pass filter including amorphous silicon films on a path on which light from an object is input to the light receiving elements.

Claims

1. An image acquisition device comprising:

an imaging unit which has a plurality of light receiving elements;

a condensing unit which condenses light which is input to the light receiving elements, and includes a plurality of microlenses which are arranged one to one with the light receiving elements on a plane; and

a band pass filter including amorphous silicon films on a path on which light from an object is input to the light receiving elements.

2. The image acquisition device according to claim 1, comprising:

a light shielding unit which is arranged between the imaging unit and the condensing unit, and which prevents light beam crosstalk between the microlenses which are adjacent to each other,

wherein the band pass filter is built into at least one of the imaging unit, the condensing unit, and the light shielding unit.

3. The image acquisition device according to claim 1, further comprising:

a light source which irradiates the object with light.

4. The image acquisition device according to claim 3,

wherein an emission peak wavelength of the light source and a transmission peak wavelength of the band pass filter match each other.

5. The image acquisition device according to claim 4,

wherein the band pass filter is configured by two mirror layers and a spacer layer which is pinched by the two mirror layers, in which each of the mirror layers has a structure in which the amorphous silicon thin films which have an optical path length of approximately λ

/4 each other in the peak wavelength (λ

) of the light source, and a thin film which is formed of a material with a different refractivity from the amorphous silicon films are alternately laminated, and the spacer layer is the amorphous silicon thin film which has optical path length of approximately λ

/2 in the peak wavelength (λ

) of the light source, or a thin film which is formed of a material with a different refractivity from the amorphous silicon films.

6. The image acquisition device according to claim 4,

wherein the band pass filter is configured by two mirror layers and a spacer layer which is pinched by the two mirror layers, in which the mirror layer has a structure in which the amorphous silicon thin films which have an optical path length of approximately (λ

2)/4 each other in a wavelength (λ

2) which is shorter than the peak wavelength (λ

) of the light source, and a thin film which is formed of a material with a different refractivity from the amorphous silicon films are alternately laminated, and the spacer layer is the amorphous silicon thin film which has optical path length of approximately (λ

3)/2 in a wavelength (λ

3) which is longer than the peak wavelength (λ

) of the light source, or a thin film which is formed of a material with a different refractivity from the amorphous silicon films.

7. The image acquisition device according to claim 4,

wherein the band pass filter has a structure in which the amorphous silicon thin film and a thin film which is formed of a material with a different refractivity from the amorphous silicon films are alternately laminated by odd number layers (2n+1, n=2, 3, and the optical path length of the band pass filter other than the n+lth layer is approximately (λ

5)/4 in a wavelength (λ

5) which is shorter than the peak wavelength (λ

) of the light source, and the optical path length of the n+lth layer is smaller than the approximate (λ

5)/4 in the wavelength (λ

5) which is shorter than the peak wavelength (λ

) of the light source.

8. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 1.

9. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 2.

10. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 3.

11. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 4.

12. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 5.

13. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 6.

14. A biometric authentication device which obtains human biological information, and performs personal authentication, comprising:

the image acquisition device according to claim 7.

15. An electronic apparatus comprising:

the biometric authentication device according to claim 8.

16. An electronic apparatus comprising:

the biometric authentication device according to claim 9.

17. An electronic apparatus comprising:

the biometric authentication device according to claim 10.

18. An electronic apparatus comprising:

the biometric authentication device according to claim 11.

19. An electronic apparatus comprising:

the biometric authentication device according to claim 12.

20. An electronic apparatus comprising:

the biometric authentication device according to claim 13.