Abstract: A multilayer optical film includes a plurality of optical repeat units which may number less than about 175 in total and which may have a combined average thickness of less than about 20 micrometers. Each of the optical repeat units includes at least four individual layers which may include at least one polymeric A layer, at least two B layers, and at least one polymeric C layer. At least one layer in the at least four individual layers can have an average thickness of less than about 50 nm. An interlayer adhesion of the individual layers in the plurality of optical repeat units can be at least about 14 grams per inch when measured at a 90 degree peel angle. The multilayer optical film may be a reflective polarizer or a multilayer optical mirror.

Abstract: A multilayer optical film includes a plurality of optical repeat units. Each of the optical repeat units includes at least four sequentially arranged first through fourth layers including first and third layers having respective f-ratios f1 and f3. The optical film has a first order reflection band having a reflection peak height Rp1 and any second order reflection band has a reflection peak height Rp2, where Rp1/Rp2?5. Rp1/Rp2 may remain at least 5 when changing at least one of the f-ratios f1 and f3 continuously by 0.2. A thickness of each of the second and fourth layers can be less than a thickness of each of the first and third layers by at least a factor of 2, or a thickness of a same one of the first and third layers can differ from a thickness of each other layer by at least a factor of 2.5.