| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a projection lens that has a greater image circle, shorter overall length, and longer back focus, maintains high performance, is compact, and is composed of the reduced number of lenses. Ž<P>SOLUTION: In a projection lens composed of three lens groups, the third lens group being a rear group, which is disposed near a diaphragm, is composed of five lenses. The three lenses, which are negative, positive, and negative lenses in this order closest to the diaphragm, are integrally cemented. The remaining two lenses are positive lenses. The entire third lens group, which is the rear group, is positive. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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