Optical filter and method of manufacturing

A method for manufacturing an optical filter, the optical filter comprising a UV-IR-absorbing layer,

• the method comprising:
• preparing a UV-IR-absorbing composition, the UV-IR-absorbing composition including a UV-IR absorber containing a phosphonic acid and a copper component, and a curable resin dispersing the UV-IR absorber therein;
• forming a UV-IR-absorbing composition film by applying the UV-IR-absorbing composition;
• and
• curing the UV-IR-absorbing composition film into the UV-IR-absorbing layer,
• wherein curing the UV-IR-absorbing composition film includes:
• exposing the UV-IR-absorbing composition film to an environment at temperature of 50 degree Celsius to 200 degree Celsius;
• and
• exposing the UV-IR-absorbing composition film to an environment at temperature of 40 degree Celsius to 100 degree Celsius and at relative humidity of 40% to 100%, and
• wherein the optical filter, in spectral transmittance at incident angle of 0 degree, has an average transmittance of 78% or more in the wavelength range of 450 nm to 600 nm, a maximum transmittance of 1% or less in the wavelength range of 750 nm to 1080 nm, a decreasing spectral transmittance with increasing wavelength in the wavelength range of 600 nm to 750 nm, and a first IR cut-off wavelength corresponding to transmittance of 50% in the wavelength range of 620 nm to 680 nm.