To improve the durability (particularly light fastness) of a dye and to obtain an optical filter having an appropriate compensating function or a function to prevent a teleoperator from producing improper operating signals by incorporating a specified organic oxidizing agent into a filter layer.

An antireflection film (the objective optical filter with an antireflection layer) has a layer structure having the order of a filter layer 2, a transparent substrate 1 and a low refractive index layer 3. The reflective index of the low refractive index layer 3 is lower than that of the transparent substrate 1. The filter layer 2 contains an organic oxidizing agent of the formula, a dye and a polymer binder. In the formula, X1 and X2 are each independently O, S, =NR1 or =CR2R3, R1-R3 are each independently H or a monovalent group, (m) and (n) are each 0, 1, 2 or 3, m+n≥2 and L1 and L2 are each independently a divalent combining group.