US Patent 10935708 Retardation film and a display apparatus including the same

A retardation film including a stacked structure including 2m tilt +C plates with m as a positive integer and a +A plate disposed over the 2m tilt +C plates. Each of the 2m tilt +C plates includes a liquid crystal layer. The liquid crystal layer includes a material satisfying nx≠ny<nz, wherein a longitudinal direction axis of the retardation film is an X-axis, a width direction axis of the retardation film substantially perpendicular to the X-axis is a Y-axis, a thickness direction axis of the retardation film substantially perpendicular to the X-axis and the Y-axis is a Z-axis, and refractive indexes of the X-axis, the Y-axis, and the Z-axis respectively correspond to nx, ny, and nz.