| 摘要 |
<P>PROBLEM TO BE SOLVED: To adjust the aberration and focus of a projection optical system partially in the surface of a lens. <P>SOLUTION: A space between neighbored lenses in a lens-barrel is divided into 9 spaces 22a-22i in the surface of the lens by partitioning members consisting of a barrel body 23 and a plate type body 24. Gas is introduced into or withdrawn out of respective spaces 22a-22i independently to change the refractive index of the gas in respective spaces in accordance with the value of adjustment, whereby the aberration and focus are adjusted. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
