LOW COLOR VARIATION OPTICAL DEVICES AND BACKLIGHT MODULES AND LIQUID CRYSAL DISPLAYS COMPRISING THE OPTICAL DEVICES

摘要

A low color variation optical device is provided. The optical device includes a cholesteric liquid crystal film, a first phase retardation film disposed above the cholesteric liquid crystal film and a second phase retardation film disposed below the cholesteric liquid crystal film, wherein the second phase retardation film includes a plurality of molecules with a tilted and twisted arrangement. The invention also provides a backlight module and a liquid crystal display including a low color variation optical device.