Optical film, polarizing plate including the same, and liquid crystal display including the same

An optical film comprising:

• a protective layer;
• and
• a contrast improving layer;
• wherein the contrast improving layer comprises a first resin layer and a second resin layer facing the first resin layer, the second resin layer and the first resin layer being sequentially stacked from the protective layer, wherein the second resin layer has a lower index of refraction than the first resin layer,
• the first resin layer has a patterned portion with at least two embossed optical patterns and a flat section between and adjacent to the at least two embossed optical patterns, the patterned portion being in at least some region of the first resin layer facing the second resin layer and satisfying Equation 1,
• a corresponding one of the embossed optical patterns having a base angle θ of about 75° to about 90°, and
• the second resin layer comprising a metal complex salt dye and/or an organic black dye, the metal complex salt dye comprising a black dye in an absence of the organic black dye:
• about 1<P/W≤about 10, Equation 1
• wherein, in Equation 1, P is a pitch (unit:
• μm) of the patterned portion, and W is a maximum width (unit:
• μm) of a corresponding one of the embossed optical patterns, and
• wherein the second resin layer has a light transmittance of about 50% to about 92% at a wavelength of 550 nm.