| 摘要 |
<P>PROBLEM TO BE SOLVED: To implement a compact, inexpensive, wide-angle, and high-performance image pickup lens and eliminate restrictions on an image pickup element to be used. <P>SOLUTION: An image pickup lens 1 comprises substantially six lenses, in order from an object side: a negative first lens L1; a negative second lens L2; a positive third lens L3; a positive fourth lens L4; a negative fifth lens L5; and a positive sixth lens L6. When R8 represents the radius of curvature of the surface on the object side of the fourth lens L4, R9 represents the radius of curvature of the surface on an image side of the fourth lens L4, and D9 represents an air gap on an optical axis between the fourth lens L4 and the fifth lens L5, the image pickup lens satisfies the following conditional expressions (1) and (2): (1) -0.11<(R8+R9)/(R8-R9)<0.26, and (2) 0.22<D9/f. <P>COPYRIGHT: (C)2013,JPO&INPIT |
