An optical sheet with a cone array is designed, simulated, and fabricated in order to substitute the dual crossed prism sheets in the edge-type LCD backlight. The optimum structure of cone textures that is compatible with the dual crossed prism sheets was obtained by simulating the backlight installed with the cone array optical sheet. A SU-8 photoresist films of thickness $30{sim}50{mu}m$ were spin-coated on a polyethylene terephtalate film (PET), and the cone texture array was formed by using the diffuse lithography that employed a photomask with circular patterns and an optical diffuser.