| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a wide-angle lens having a high imaging performance with a large angle of view. <P>SOLUTION: This wide-angle lens includes a front group Gf disposed at an object side with respect to an aperture stop, and a rear group Gr disposed at an image side with respect to the aperture stop. The front group includes a sub group Ga having a negative refractive power, the sub group Ga includes, in order from the object side, at least three negative lenses, at least one of the at least three negative lenses is an aspherical negative meniscus lens having such a shape that negative power is getting smaller from the lens center towards the periphery. A cemented lens formed by bonding a positive lens, a negative lens and a positive lens is disposed at the image side with respect to the sub group Ga, and prescribed conditions are satisfied. An antireflection film is provided on at least one surface of optical surfaces of the front group, and the antireflection film includes at least one layer formed by a wet process. <P>COPYRIGHT: (C)2012,JPO&INPIT |
