一、引言光栅盘、度盘为数控、数显的关键元件之一。目前制造光栅有刻划法,投影曝光法和接触复制法等。投影光刻法优点较多,如效率高、精度高。其弱点是采用火棉胶作感光乳剂膜层,强度差,怕摩擦。且由于是有底层的胶膜,故光栅对比度及均匀性较差,分 First, the introduction grating disc, dial for the NC, one of the key digital components. At present, there are grating engraving method, projection exposure method and contact reproduction method. Projection lithography has many advantages, such as high efficiency and high precision. Its weakness is the use of collodion for emulsion film, poor strength, fear of friction. And because there is a bottom of the film, so the grating contrast and uniformity is poor, points