| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a compact fixed-focus lens including a compact and light-weight focus group and a compact and light-weight vibration proof group and having high image forming performance. <P>SOLUTION: The fixed-focus lens includes a master group M<SB POS="POST">1</SB>having positive refractive power, a focus group F<SB POS="POST">1</SB>arranged to be closer to the side of an image surface IMG than the master group M<SB POS="POST">1</SB>and having negative refractive power, a vibration proof group V<SB POS="POST">1</SB>arranged to be closer to an object side than the master group M<SB POS="POST">1</SB>and having negative refractive power, a front component group FC<SB POS="POST">1</SB>arranged to be closer to the object side than the vibration proof group V<SB POS="POST">1</SB>and having positive refractive power, and a rear group R<SB POS="POST">1</SB>arranged to be closer to the side of the image surface IMG than the focus group F<SB POS="POST">1</SB>and having positive refractive power. The vibration proof group V<SB POS="POST">1</SB>is moved in a direction perpendicular to an optical axis, to perform vibration proof correction. The focus group F<SB POS="POST">1</SB>is moved to the side of the image surface IMG from the object side along the optical axis, to perform focusing from the infinity focusing state to the closest distance focusing state. <P>COPYRIGHT: (C)2013,JPO&INPIT |
