| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an imaging optical system capable of sufficiently generating axial chromatic aberration while suppressing generation of chromatic aberration of magnification. <P>SOLUTION: The imaging optical system comprises in order from an object side, a front group, an aperture, and a rear group. The front group includes a positive lens and a negative lens, and satisfies all of the following conditional expressions: 30≤¾νd<SB POS="POST">p</SB>-νd<SB POS="POST">n</SB>¾; 0.1≤y<SB POS="POST">pn</SB>/y<SB POS="POST">i</SB>≤0.7; and -0.4≤Δf<SB POS="POST">g</SB>/f≤-0.1, whereνd<SB POS="POST">p</SB>is the Abbe number of the positive lens,νd<SB POS="POST">n</SB>is the Abbe number of the negative lens, y<SB POS="POST">pn</SB>is a maximum height of a principal ray in the positive lens or the negative lens, y<SB POS="POST">i</SB>is the height of an image,Δf<SB POS="POST">g</SB>is the axial chromatic aberration of light (g line) with a wavelength of 435 nm when using light (e line) with the wavelength of 546nm as a criterion, and f is a focal length of an entire system in the light (e line) with the wavelength of 546nm. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
