The development of coating technique to lower the reflected light and increase the optical efficiency of an optical system is a very important topic for modern optical elements. Recently, the use of anti-reflection (AR) structured surface has been proposed as an applicable alternative based on both the theoretical and the experimental study. In this article, antireflection structured surface was analyzed by the finite difference time domain (FDTD) method in the visible light spectrum and has been successfully fabricated on plastic substrate by nano-imprint process. The FDTD numerical calculation was used to analyze the AR structured surface by the designed profile 3-D pyramid and conical structure. Both of the structures showed the antireflection (AR) effect (reflectance<1%) when the aspect ratio of the 3D structure was larger than 0.8. In the nano-imprint process, hot embossing and UV curing process were applied to generate 3D nano-structure on plastic substrate as PMMA and PET. The optical property of the fabricated polymer film showed good agreement with the simulation result. In another work, we proposed a new type of metal embedded soft photo-mask based on a PMDS mold. Due to its compliance, this new soft photo-mask can from intimate contact with a slight-curved sapphire wafer and carry out UV exposure in photolithography and therefore forming PR microstructures on a sapphire substrate. During the exposure process, part of incident light is selectively blocked from metal film and others are guided by the convex PDMS structures and onto the photo-resist layer. For the soft PDMS photo-mask, hexagonal arrays of PR micro-pillars with a diameter around 1 µm and a height of 1.4 µm are successfully created on a 2 inch sapphire substrate. Subsequently, the pattern sapphire substrates (PSS) for LEDs can be readily obtained by applying ICP etching on this PR-patterned sapphire substrate. In addition, pulsed lasers were used to fabricate micro/nano structures on the transparent conducting oxide (TCO) layers of the light emitting diodes (LEDs) with pattern sapphire substrate to destroy the total internal reflectionat TCO/air and enhance the light extraction efficiency. It can improve LED light extraction efficiency up to 16%.