INFRARED TRANSMISSIVE FILM AND PRODUCTION METHOD OF INFRARED TRANSMISSIVE FILM

摘要

PROBLEM TO BE SOLVED: To provide an infrared transmissive film that transmits light at a wavelength greater than 780 nm and equal to or smaller than 2000 nm.SOLUTION: A infrared transmissive film 10 includes: a rugged structure layer 20 having a rugged surface 21 formed by minute protrusions 22 arranged at an average interval dof 380 nm or less; and a metal thin film 3 disposed on the rugged surface of the rugged structure layer and extending to follow the rugged profile of the rugged surface. A maximum transmittance for light that is incident along the normal direction of the infrared transmissive film and is in an infrared band at a wavelength greater than 780 nm and equal to or smaller than 2000 nm is larger than a maximum transmittance for light that is incident along the normal direction of the infrared transmissive film and is in a visible ray band at a wavelength of 380 nm or greater and 780 nm or smaller.