Patent ID: RE39857

Claim:
An infrared absorption filter which has a transmittance of not higher than 30 % in the near-infrared region in the wavelength range of 800 to 1100 nm; a difference of 10 % or less between a maximum value and a minimum value of transmittance in the visible light region in the wavelength range of 450 to 650 nm; and a transmittance of not lower than 50 % at a wavelength of 550 nm, said filter, after being left to stand in the air atmosphere at a temperature of 60 ° C. and a humidity of 95 % for 1000 hours, having a transmittance of not higher than 30 % in the near-infrared region in the wavelength range of 800 to 1100 nm, and a difference of 10 % or less between a maximum value and a minimum value of transmittance in the visible light region in the wavelength range of 450 to 650 nm, said filter having an infrared-absorbing layer on a transparent substrate, the infrared-absorbing layer being composed of a coloring matter, dye or pigment absorbing infrared radiation and a polymer serving as a dispersing medium and the transparent substrate having a total light transmittance of not lower than 89 %, a haze of not higher than 1 . 6 %, a coefficient of static friction of not higher than 0 . 6 and a coefficient of dynamic friction of not higher than 0 . 6 .