Plastic optical characteristics include two categories: one for the transfer characteristics, including light transmission, reflection, scattering and refraction; the other for light conversion features, including light absorption, thermal, photochemical, optoelectronics and light photochromic and so on.Used to characterize light transmission characteristic indicators are transmittance, haze, refractive index, birefringence and the dispersion and so on.In the indicators, the light transmittance and haze two indicators main characterize translucent of the material,the refractive index, birefringence and scattering three main indicators used to characterize the quality of translucent. A good transparent material, requiring the excellent performance and balanced.