Optical film

A liquid crystal display, comprising:

• a liquid crystal panel having an upper polarizing plate and a lower polarizing plate which are attached to upper and lower portions of the liquid crystal panel, respectively;
• and
• a light source formed at a lower portion of the lower polarizing plate of the liquid crystal panel,
• wherein the lower polarizing plate is a reflective polarizing plate, comprising:
• a polarizer having an optical transmission axis and an optical absorption axis perpendicular to the transmission axis;
• and
• an optical film comprising an anisotropic layer that comprises a dichroic dye capable of forming a lyotropic liquid crystal phase,
• wherein an absolute value of the difference between the refractive index with respect to light that has wavelength within the range of visible light and that has polarized axis in a direction parallel to an optical transition dipole moment of an anisotropically absorbing fragment of the dichroic dye and the refractive index with respect to light that has wavelength within the range of visible light and that has polarized axis in a direction perpendicular to an optical transition dipole moment of an anisotropically absorbing fragment of the dichroic dye is 0.2 or more;
• wherein light having a polarized axis in a direction parallel to the optical transition dipole moment is reflected by the anisotropic layer, and light having polarized axis in a direction perpendicular to the optical transition dipole moment is transmitted through the anisotropic layer;
• and
• wherein the optical transition dipole moment of the dichroic dye or a projection of the optical transition dipole moment on the anisotropic layer plane is parallel to the optical absorption axis of the polarizer.