| 摘要 |
PROBLEM TO BE SOLVED: To provide a bifocal photographic lens having high performance while shortening the overall optical length, and to provide a photographic lens available for the bifocal photographic lens. SOLUTION: The photographic lens includes a first lens system 13 having, in order from the object side: a first lens 1 having a positive refractive power; a second lens 2 having a negative refractive power; an aperture diaphragm 10; and a third lens 3 having a positive refractive power. The first lens system 13 satisfies the following conditional expressions: (1) TL<SB>t</SB>/f<SB>t</SB><1.0; (2) 3.0<f<SB>t</SB>/f<SB>t1</SB><3.2; (3) 1.9<f<SB>t</SB>/f<SB>t3</SB><2.1; and (4) 20<v<SB>t1</SB>-v<SB>t2</SB>. COPYRIGHT: (C)2007,JPO&INPIT
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