Optical filter, solid-state imaging element, imaging device lens and imaging device

An imaging device lens comprising:

• a near infrared ray absorbing layer formed on at least one surface of a lens main body, which comprises:
• a near infrared ray absorbing dye (A);
• and
• a transparent resin (B), the near infrared ray absorbing dye (A) being dispersed in the transparent resin (B);
• and
• a selective wavelength shielding layer provided on one side or both sides of the near infrared ray absorbing layer, the selective wavelength shielding layer transmitting visible light in a wavelength range of from 420 to 695 nm therethrough and shielding near infrared light in a wavelength range of from 720 to 1,100 nm,
• wherein
• the near infrared ray absorbing dye (A) comprises a near infrared ray absorbing dye (A1), an absorption spectrum of the near infrared ray absorbing dye (A1) in a wavelength range of from 400 to 1,000 nm having a maximum absorption peak at a peak wavelength, wherein the absorption spectrum is measured in a state in which the near infrared ray absorbing dye (A1) is dissolved in a solvent for dye having a refractive index (n20d) of less than 1.500;
• the absorption spectrum of the near infrared ray absorbing dye (A1) satisfies conditions (a) and (b):
• (a) a full width at half maximum of the maximum absorption peak is not more than 60 nm;
• and
• (b) 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 maximum absorption peak by a wavelength difference between 630 nm and the peak wavelength (nm) is from 0.010 to 0.050;
• the selective wavelength shielding layer comprises a first dielectric multilayered film and a second dielectric multilayered film, wherein the first dielectric multilayer film transmits visible light and has a first reflecting range in which near infrared light is reflected and a transmittance of the near infrared light is not more than 5%, and the second dielectric multilayer film transmits visible light, reflects ultraviolet light, and optionally has a second reflecting range in which near infrared light is reflected and a transmittance of the near infrared light is not more than 5%;
• and
• the near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, and an amount of change of transmittance (D) expressed by 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.

An optical filter comprising:

• a near infrared ray absorbing layer which comprises:
• a near infrared ray absorbing dye (A);
• and
• a transparent resin (B), the near infrared ray absorbing dye (A) being dispersed in the transparent resin (B);
• and
• a selective wavelength shielding layer provided on one side or both sides of the near infrared ray absorbing layer, the selective wavelength shielding layer transmitting visible light therethrough and shielding near infrared light,
• wherein
• the near infrared ray absorbing dye (A) comprises a near infrared ray absorbing dye (A1), an absorption spectrum of the near infrared ray absorbing dye (A1) in a wavelength range of from 400 to 1,000 nm having a maximum absorption peak at a peak wavelength, wherein the absorption spectrum is measured in a state in which the near infrared ray absorbing dye (A1) is dissolved in a solvent for dye having a refractive index (n20d) of less than 1.500;
• the absorption spectrum of the near infrared ray absorbing dye (A1) satisfies conditions (a) and (b):
• (a) a full width at half maximum of the maximum absorption peak is not more than 60 nm;
• and
• (b) 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 maximum absorption peak by a wavelength difference between 630 nm and the peak wavelength (nm) is from 0.010 to 0.050;
• the selective wavelength shielding layer comprises a first dielectric multilayered film and a second dielectric multilayered film, wherein the first dielectric multilayer film transmits visible light and has a first reflecting range in which near infrared light is reflected and a transmittance of the near infrared light is not more than 5%, and the second dielectric multilayer film transmits visible light in a wavelength range of from 420 to 695 nm, reflects ultraviolet light in a wavelength range of 400 nm or shorter, and has a second reflecting range in which near infrared light is reflected and a transmittance of the near infrared light is not more than 5%, wherein a wavelength at a shorter wavelength end of the second reflecting range is equal to or shorter than a wavelength at a longer wavelength end of the first reflecting range, and a wavelength at a longer wavelength end of the second reflecting range is at least 1100 nm;
• and
• the near infrared ray absorbing layer has a transmittance of visible light of from 450 to 600 nm of 70% or more, and an amount of change of transmittance (D) expressed by 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.