Abstract: A projection system comprising a first imaging component, at least a second imaging component, and a color combiner. The first and second imaging components each comprise an imager and a reflective polarizer that is configured to at least partially separate a light beam from the imager into a first portion and second portion, where the first portion and the second portion have substantially orthogonal polarization states. The first portions of the light beams are directed in the same direction above or below a plane defined by the second portions of the light beams. The color combiner is configured to combine the second portions of the light beams, where the second portions of the light beams have substantially orthogonal polarization states prior to entering the color combiner.

Abstract: An optical stack includes a first liquid crystal layer and a j-retarder disposed on the liquid crystal layer. The j-retarder includes a simultaneous biaxially stretched polymeric film being substantially non-absorbing and non-scattering for at least one polarization state of visible light. The j-retarder has x, y, and z orthogonal indices of refraction where at least two of the orthogonal indices of refraction are not equal, an in-plane retardance being 100 nm or less and an absolute value for an out-of-plane retardance being 55 nm or greater.

Abstract: An optical body includes a) first particles comprising a first cholesteric liquid crystal material and b) a second cholesteric liquid crystal material. The first particles and the second cholesteric liquid crystal material form a structure where the first cholesteric liquid crystal material has a pitch that is different than the second cholesteric liquid crystal material. In one example, the second cholesteric liquid crystal material is in the form of second particles. In another example, the first particles are dispersed in a matrix of the second cholesteric liquid crystal material. In other examples, the optical body has more than one layer. In addition, one or more additional cholesteric liquid crystal materials can be used in the optical body. These optical bodies can be used as a reflective polarizer and can be used in a display.

Abstract: A method for making a polarizer from a polymeric film having an original length and comprising a hydroxylated linear high polymer includes stretching the polymeric film to a stretched length of from about 3.5 times to about 7.0 times the original length, immersing the polymeric film in an aqueous dehydration catalyst, and heating the polymeric film and the catalyst to effect partial dehydration of the polymeric film, wherein light absorbing, vinylene block segments are formed.