The paper introduces a newly-developed broad beam cold cathod ion source used for ion-assisted-deposition of thin films.Compared with Kaufman-type hot cathod ion source widely used at home and abroad,it has many advantages of long life,unpollution,simple construction,less power,easy operation,etc..The strength of ZnS films and G|AlSiO_x|A films deposited by ion-assisted-deposition with broad beam cold cath- od ion source are separately 10 times and 8 times higher than that stipulat- ed for by National Stand...