The present invention provides a birefringent optical film having a high orientation for easily obtaining a desired retardation value and also a small photoelastic coefficient. The birefringent optical film includes at least two kinds of polymer materials. A total of products of Cn and Wn satisfies a numerical formula (1): .SIGMA.(Cn.times.Wn).ltoreq.30.times.10.sup.-8 cm.sup.2/N (1) where Cn and Wn denote respectively a photoelastic coefficient and a volume fraction of each polymer material, and at least one of the polymer materials of the film has a photoelastic coefficient value of at least 60.times.10.sup.-8 cm.sup.2/N.

 
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