To a provide phase difference plate having high uniformity with an undrawn film of a polycarbonate.

An undrawn film of a polycarbonate obtained by casting, not substantially containing a residual solvent and having ≤0.8 J/g of heat absorption at the glass transition temperature of the film is drawn at a temperature not exceeding the glass transition temperature, preferably in the range from the glass transition temperature to (the glass transition temperature)-20°C.