| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To obtain a high-resolution zoom lens for projection, constituted of six groups and for sufficiently correcting various aberrations in all of the zooming area while securing sufficiently long back focus, and a projection type display apparatus, on which a zoom lens for projection like this is mounted. <P>SOLUTION: The zoom lens for projection includes, from an enlargement side, a negative first group G<SB>1</SB>, a negative second group G<SB>2</SB>, a positive third group G<SB>3</SB>, a positive fourth group G<SB>4</SB>, a positive or negative fifth group G<SB>5</SB>, and a positive sixth group G<SB>6</SB>, and is made to be a telecentric system on a reduction side. During zooming, the first group G<SB>1</SB>, the second group G<SB>2</SB>and the sixth group G<SB>6</SB>are fixed, and the third to fifth groups G<SB>3</SB>to G<SB>5</SB>are moved. Furthermore, the first group G<SB>1</SB>is a group for focusing while being fixed during zooming, the second group G<SB>2</SB>is a group fixed during zooming and during focusing. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
