| 摘要 |
PROBLEM TO BE SOLVED: To achieve a size reduction, a wider angle, and a cost reduction in an image pickup lens while maintaining the high optical performance in which color aberrations are satisfactorily corrected. SOLUTION: The image pickup lens includes, in order from the object side: a first lens group G1 that has negative refractive power as a whole; a second lens group G2 that has positive or negative power as a whole; an aperture diaphragm; a third lens group G3 that has positive power as a whole; and a diffractive optical element GD in which at least one face is flat and a diffractive structure is formed on at least one face. When the focal distance of the entire system is defined as f and the focal distance of the diffractive optical element GD is f<SB>DOE</SB>, conditional expression (1)-0.2<f/f<SB>DOE</SB><0.2 is satisfied. COPYRIGHT: (C)2009,JPO&INPIT
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