Patent ID: 7663686

Claim:
A lens module, comprising: a barrel defining a through hole; at least one plastic lens accommodated in the through hole; and a UV/IR cut filter mounted on the barrel and configured for preventing entry of both UV light and IR light into the barrel; wherein, the UV/IR cut filter comprises a UV/IR cut filter film which is a film stack, the film stack comprising a plurality of high refractive index layers and a plurality of low refractive index layers alternately stacked one on another, wherein the film stack is represented as follows: (3.5H3.5L) 7 (2.5H2.5L) 7 (HL) 6 (0.76H0.76L) 6 , wherein H represents a high refractive index layer having a base optical thickness equal to one fourth of a reference wavelength associated with the UV/IR cut filter, L represents a low refractive index layer having a base optical thickness equal to one fourth of the reference wavelength associated with the UV/IR cut filter, the expression enclosed in each pair of parentheses represents a filter cavity, and each superscript represents the number of repetitions of the expression enclosed in that pair of parentheses.