OPTICAL FILTER, SOLID-STATE IMAGING ELEMENT, IMAGING DEVICE LENS AND IMAGING DEVICE

• US 20140091419A1
• Filed: 12/06/2013
• Published: 04/03/2014
• Est. Priority Date: 06/06/2011
• Status: Active Grant

• Current Assignee: AGC, Inc.
• Original Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Inventors: Hasegawa, Makoto, Kashiwabara, Satoshi, Shimoda, Hiroshi, Shibuya, Takashi, Osawa, Mitsuo, Kumai, Hiroshi, Sekikawa, Kenta, Kamijyo, Katsushi, Arishima, Hiroyuki
• Granted Patent: US 9,268,072 B2
• Time in Patent Office: Days
• US Class Current: 257/432
• CPC Class Codes: C09B 23/086 more than five >CH- groups
• CPC Class Codes: C09B 23/107 four >CH- groups
• CPC Class Codes: C09B 57/007 Squaraine dyes
• CPC Class Codes: G02B 1/04 made of organic materials, e.g. plastics G02B1/08 takes precedence
• CPC Class Codes: G02B 13/004 having four lenses
• CPC Class Codes: G02B 13/005 having spherical lenses only
• CPC Class Codes: G02B 5/208 for use with infrared or ultraviolet radiation, e.g. for separating visible light from infrared and/or ultraviolet radiation
• CPC Class Codes: G02B 5/223 containing organic substances, e.g. dyes, inks or pigments
• CPC Class Codes: G02B 5/282 reflecting for infrared and transparent for visible light, e.g. heat reflectors, laser protection
• CPC Class Codes: H01L 27/14621 Colour filter arrangements

Abstract

The present invention relates to an optical filter, a solid-state imaging element and an imaging device lens which contain a near infrared ray absorbing layer having a specific near infrared ray absorbing dye dispersed in a transparent resin having a refractive index of 1.54 or more, and also relates to an imaging device containing the solid-state imaging element or the imaging device lens. The near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change of transmittance of not more than −0.8

Claims

1. An optical filter comprising a near infrared ray absorbing layer having a near infrared ray absorbing dye (A) dispersed in a transparent resin (B), wherein

the near infrared ray absorbing dye (A) comprises a near infrared ray absorbing dye (A1) having a maximum absorption peak such that in an absorption spectrum of light in a wavelength region of from 400 to 1,000 nm as measured upon being dissolved in a solvent for dye having a refractive index (n₂₀d) of less than 1.500, a peak wavelength is present in a region of from 695 to 720 nm, a full width at half maximum is not more than 60 nm, and when calculated with an absorbance at the peak wavelength being 1, a value obtained by dividing a difference between an absorbance at 630 nm and an absorbance at the peak wavelength by a wavelength difference between 630 nm and the peak wavelength is from 0.010 to 0.050;

the transparent resin (B) has a refractive index (n₂₀d) of 1.54 or more; and

the near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change D of transmittance expressed by the following equation (1) of not more than −

0.8;

D(%/nm)=[T₇₀₀(%)−

T₆₃₀(%)]/[700(nm)−

630(nm)] 

 

(1)

wherein

in the equation (1), T₇₀₀ is a transmittance at a wavelength of 700 nm in a transmission spectrum of the near infrared ray absorbing layer; and

T₆₃₀ is a transmittance at a wavelength of 630 nm in the transmission spectrum of the near infrared ray absorbing layer.

2. The optical filter according to claim 1, wherein the near infrared ray absorbing dye (A1) is a dye having a maximum absorption peak exhibiting a peak wavelength in a region of from 700 to 720 nm in the absorption spectrum, and the near infrared ray absorbing layer has an amount of change D of transmittance expressed by the equation (1) of not more than −

0.86.

3. The optical filter according to claim 1, wherein the near infrared ray absorbing dye (A1) is composed of at least one member selected from squarylium compounds represented by the following formula (F1):

4. The optical filter according to claim 1, wherein the near infrared ray absorbing dye (A) further comprises a near infrared ray absorbing dye (A2) having a maximum absorption peak such that in an absorption spectrum of light in a wavelength region of from 400 to 1,000 nm as measured upon being dissolved in a solvent for dye having a refractive index (n₂₀d) of less than 1.500, a peak wavelength is present in a region of more than 720 nm and not more than 800 nm, and a full width at half maximum is not more than 100 nm.

5. The optical filter according to claim 4, wherein the near infrared ray absorbing dye (A2) is composed of at least one member selected from cyanine compounds represented by the following general formula (F2):

6. The optical filter according to claim 1, wherein the transparent resin (B) comprises at least one member selected from the group consisting of an acrylic resin, an epoxy resin, an ene/thiol resin, a polycarbonate resin, and a polyester resin.

7. The optical filter according to claim 1, wherein in the near infrared ray absorbing layer, a proportion of the near infrared ray absorbing dye (A1) is from 3 to 100% by mass relative to the whole amount of the near infrared ray absorbing dye (A), and a proportion of the near infrared ray absorbing dye (A) is from 0.05 to 5 parts by mass based on 100 parts by mass of the transparent resin (B).

8. The optical filter according to claim 1, wherein the near infrared ray absorbing layer has a film thickness of from 0.1 to 100 μ

m.

9. The optical filter according to claim 1, further comprising, on one side or both sides of the near infrared ray absorbing layer, a selective wavelength shielding layer transmitting visible light of from 420 to 695 nm therethrough and shielding light in a wavelength region of from 710 to 1,100 nm.

10. The optical filter according to claim 9, wherein the selective wavelength shielding layer is composed of a dielectric multilayered film in which a low refractive index dielectric film and a high refractive index dielectric film are stacked alternately each other.

11. The optical filter according to claim 9, having a transmittance of visible light of from 420 to 620 nm being 70% or more;

a transmittance of light in a wavelength region of from 710 to 860 nm being not more than 0.3%; and

an amount of change Df of transmittance expressed by the following equation (2) being not more than −

0.8;

Df(%/nm)=[Tf₇₀₀(%)−

Tf₆₃₀(%)]/[700(nm)−

630(nm)] 

 

(2)

wherein

in the equation (2), Tf₇₀₀ is a transmittance at a wavelength of 700 nm in a transmission spectrum of the optical filter; and

Tf₆₃₀ is a transmittance at a wavelength of 630 nm in the transmission spectrum of the optical filter.

12. A solid-state imaging element comprising a photoelectric conversion element and, formed on the photoelectric conversion element, a near infrared ray absorbing layer having a near infrared ray absorbing dye (A) dispersed in a transparent resin (B), wherein

the near infrared ray absorbing dye (A) comprises a near infrared ray absorbing dye (A1) having a maximum absorption peak such that in an absorption spectrum of light in a wavelength region of from 400 to 1,000 nm as measured upon being dissolved in a solvent for dye having a refractive index (n₂₀d) of less than 1.500, a peak wavelength is present in a region of from 695 to 720 nm, a full width at half maximum is not more than 60 nm, and when calculated with an absorbance at the peak wavelength being 1, a value obtained by dividing a difference between an absorbance at 630 nm and an absorbance at the peak wavelength by a wavelength difference between 630 nm and the peak wavelength is from 0.010 to 0.050;

the transparent resin (B) has a refractive index (n₂₀d) of 1.54 or more; and

the near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change D of transmittance expressed by the following equation (1) of not more than −

0.8;

D(%/nm)=[T₇₀₀(%)−

T₆₃₀(%)]/[700(nm)−

630(nm)] 

 

(1)

wherein

in the equation (1), T₇₀₀ is a transmittance at a wavelength of 700 nm in a transmission spectrum of the near infrared ray absorbing layer; and

T₆₃₀ is a transmittance at a wavelength of 630 nm in the transmission spectrum of the near infrared ray absorbing layer.

13. The solid-state imaging element according to claim 12, further comprising, on the photoelectric conversion element, at least one member selected from a light shielding layer, a flattened layer, a color filter layer, and a microlens.

14. The solid-state imaging element according to claim 12, further comprising, on one side or both sides of the near infrared ray absorbing layer, a selective wavelength shielding layer transmitting visible light of from 420 to 695 nm therethrough and shielding light in a wavelength region of from 710 to 1,100 nm.

15. The solid-state imaging element according to claim 14, wherein the selective wavelength shielding layer is composed of a dielectric multilayered film in which a low refractive index dielectric film and a high refractive index dielectric film are stacked alternately each other.

20. An imaging device comprising the solid-state imaging element described in claim 12.

16. An imaging device lens comprising a near infrared ray absorbing layer having a near infrared ray absorbing dye (A) dispersed in a transparent resin (B), wherein

the near infrared ray absorbing dye (A) comprises a near infrared ray absorbing dye (A1) having a maximum absorption peak such that in an absorption spectrum of light in a wavelength region of from 400 to 1,000 nm as measured upon being dissolved in a solvent for dye having a refractive index (n₂₀d) of less than 1.500, a peak wavelength is present in a region of from 695 to 720 nm, a full width at half maximum is not more than 60 nm, and when calculated with an absorbance at the peak wavelength being 1, a value obtained by dividing a difference between an absorbance at 630 nm and an absorbance at the peak wavelength by a wavelength difference between 630 nm and the peak wavelength is from 0.010 to 0.050;

the transparent resin (B) has a refractive index (n₂₀d) of 1.54 or more; and

the near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, a transmittance of light in a wavelength region of from 695 to 720 nm of not more than 10%, and an amount of change D of transmittance expressed by the following equation (1) of not more than −

0.8;

D(%/nm)=[T₇₀₀(%)−

T₆₃₀(%)]/[700(nm)−

630(nm)] 

 

(1)

wherein

in the equation (1), T₇₀₀ is a transmittance at a wavelength of 700 nm in a transmission spectrum of the near infrared ray absorbing layer; and

T₆₃₀ is a transmittance at a wavelength of 630 nm in the transmission spectrum of the near infrared ray absorbing layer.

17. The imaging device lens according to claim 16, wherein the near infrared ray absorbing layer is formed on at least one surface of a lens main body.

18. The imaging device lens according to claim 16, further comprising, on one side or both sides of the near infrared ray absorbing layer, a selective wavelength shielding layer transmitting visible light of from 420 to 695 nm therethrough and shielding light in a wavelength region of from 710 to 1,100 nm.

19. The imaging device lens according to claim 18, the selective wavelength shielding layer is composed of a dielectric multilayered film in which a low refractive index dielectric film and a high refractive index dielectric film are stacked alternately each other.

21. An imaging device comprising the imaging device lens described in claim 16.