| 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. The surface on the object side of the second lens L2 is a plain surface or a recessed surface, and the surface on the image side of the third lens L3 is a plain surface or a recessed surface. When D6+D7 represents an air gap on an optical axis between the third lens L3 and the fourth lens L4, f represents the focal length of the entire system, and D12 represents the central thickness of the sixth lens L6, the image pickup lens satisfies the following conditional expressions (1) and (2): (1) 0.00<(D6+D7)/f<1.30, and (2) 1.25<D12/f. <P>COPYRIGHT: (C)2013,JPO&INPIT |
