Abstract:

A new exposure mode to produce optical variable images was studied and advanced by using digital grating,and a laser direct writing experimental system was designed,where Lcos was the image generator.There are two improvements in this new method compared with the traditional ways,①planar array exposure was adopted instead of using Lcos to be image generator,②the Lcos worked  as image generator,and as the optical diffractive element.As a result,the Lcos digital grating can get higher quality arbitrary spot pattern with phase information.Resolution of  the method can reach to 1000 lines per mm,and in the whole resolution range can generate the spot of any line width wanted,therefore higher quality optical variable image is accessible.

Key words: laser direct writing, digital grating, spatial light modulator, optical variable device

摘要：

研究了以数字光栅模板形成光变图像的方法,搭建了以Lcos空间光调制器为图像发生器的光刻实验平台。该方法与传统光刻技术相比有两大改进:采用数字光栅模板替代分束元件及机械旋转结构;以Lcos为图像发生器,采用面阵式的曝光得到高质量的具有位相信息的任意光斑图形。该方法的分辨率可达1000线/mm,能够制作出高质量的光变图像，如2D/3D图像以及各种精密的微刻图像和文字。



关键词: 激光直写, 数字光栅, 空间光调制器, 光变图像