Study Of Large Format High Speed Laser Direct Writing System Based On PMAC

Laser direct writing (LDW) that has been widely used in many areas of industry is an advanced of optical fabrication technique. The research and application fields of LDW have some differences at home and abroad. Foreign studies mainly focus on the high speed precise laser lithography based on single laser beam, which is widely used in IC manufacturing, micro-optics components micromachining, laser wiring and optical detecting, etc. And many domestic institutes mainly focus on the research of the optical variable device, binary optical components fabrication and various mask plates based on the LDW technique.This thesis designed a LDW system with high speed and wide writing area, which can be used in single laser beam writing and interference writing. Linear motors and high precise grating rulers are used to realize a full-closed-loop location control system, the PMAC controller also has been used to get the high speed and precision control. The accuracy between dots is 1 micron while 0.5 micron in dot, the speed reaches 500dots/s in the dot-dot lithography and 3000dots/s in the vector lithography. The diode-pumped solid state laser (DPSSL) is used as an optical source. By converting the files of image to PMAC control signals in VC++6.0, the output of laser pulse and the system's motion can be controlled. The 610mm×800mm optical variable image with kinetic and 3D effect can be obtained by the high speed direct writing experiment using continuing pulse exposal mode. This LDW system already achieved the level of industrialization, can be utilized to manufacture broad dot-matrix normal rainbow hologram and universal stencil. The paper also did some exploratory researches of the single laser beam writing which can be used in the area of IC manufacture and laser sophisticated processing.