Patent ID: 7025908

Claim:
An optical filter, comprising a near infrared light absorption layer containing the following component A and/or the following component B, wherein the phosphorus atom content in the near infrared light absorption layer is 0.4 to 1.3 mol per mole of copper ions, and the copper ion content in the near infrared light absorption layer is 2 to 60 wt %: Component A: a component composed of copper ions and a phosphoric ester compound expressed by the following Formula (1); Component B: a copper phosphate compound obtained by reaction of a copper compound with said phosphoric ester compound, (in Formula (1), R is a group expressed by the following Formula (2), (3), (4), (5), (6), (7), (8), or (9), an alkyl group, an aryl group, an aralkyl group, or an alkenyl group, n is 1 or 2, and when n is 1, the R groups may be the same or different), (in Formulas (2) to (9), R 11 to R 17 are C 1 to C 20 alkyl groups or C 6 to C 20 aryl groups or aralkyl groups (where the one or more hydrogen atoms bonded to the carbon atoms that make up aromatic rings may be substituted with C 1 to C 6 alkyl groups or halogens), R 21 to R 25 are hydrogen atoms or C 1 to C 4 alkyl groups (where R 23 , R 24 , and R 25 cannot all be hydrogen atoms), R 31 and R 32 are C 1 to C 6 alkylene groups, R 41 is a C 1 to C 10 alkylene group, R 51 and R 52 are C 1 to C 20 alkyl groups, R 61 is a hydrogen atom or methyl group, m is an integer from 1 to 6, k is an integer from 0 to 5, p is an integer from 2 to 97, and r is an integer from 1 to 4).