Patent ID: 7872711

Claim:
An optical sheet for a backlight unit of a TFT-LCD, comprising: a transparent base sheet; and a light diffusion layer in which a diffusion pattern comprised of a plurality of protrusions is formed on the transparent base sheet, wherein the diffusion pattern has an aspect ratio of 0.8 or more, the aspect ratio satisfies below: a ⁢ ⁢ thickness ⁡ ( d ) ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ protrusion a ⁢ ⁢ radius ⁢ ⁢ ( 1 ) ⁢ ⁢ of ⁢ ⁢ a ⁢ ⁢ unit ⁢ ⁢ body ⁢ ⁢ portion ⁢ ⁢ of ⁢ ⁢ the ⁢ ⁢ protrusion ≥ 0.8 .