Multi-level optical diffuser with high near infrared clarity

An optically diffusive film comprising a structured first major surface comprising a plurality of substantially parallel substantially planar first surfaces arranged across the first major surface at a plurality of different first height levels along a thickness direction of the optically diffusive film, a height difference between any two of the first surfaces being S times Hmin, S a number within 15% of an integer and Hmin a height difference between lowest and next-lowest first surfaces;

• wherein, for a substantially collimated incident light substantially normally incident on a plane of the first major surface:
• for at least a first wavelength in a visible wavelength range extending from about 400 nm to about 700 nm, the optically diffusive film has an optical haze Hv and an optical clarity Cv;
• and
• for at least a second wavelength in an infrared wavelength range extending from about 700 nm to about 2000 nm, the optically diffusive film has an optical haze Hi and an optical clarity Ci, Hv/Hi≥1.5 and Ci/Cv≥1.5.