  A special beam line for high energy electron radiography is designed,
including achromat and imaging systems. The requirement of the angle and
position correction on the target from imaging system can be approximately
realized by fine tuning the quadrupoles used in the achromat. The imaging
system is designed by fully considering the limitation from the laboratory and
beam diagnostics devices space. Two kinds of imaging system are designed and
both show a good performance of imaging by beam trajectory simulation. The
details of the beam optical requirement and optimization design are presented
here. The beam line is designed and prepared to install in Tsinghua university
linear electron accelerator laboratory for further precise electron radiography
experiment study.
