A macro lens comprised of a front lens group of a retrofocus type and a rear lens group of which component lenses are aligned in the order from the closest to the subject. The front lens group includes a first lens of a negative meniscus lens having its convex surface projecting toward the object, a second lens of a positive lens having its one surface with greater curvature oriented toward the object, a third lens of a positive lens having its one surface with greater curvature oriented toward the object, a fourth lens of a negative lens having its concave surface with greater curvature oriented toward the imaging plane, fifth and sixth lenses of a junction lens in combination of a negative lens with a positive lens, the negative lens having its one surface with greater curvature oriented toward the object, across a space having an aperture stop, and a seventh lens of a positive lens having its one surface with greater curvature oriented toward the imaging plane, the rear lens group including an eighth negative lens and a ninth positive lens, the macro lens providing relations expressed as follows:

1.0|F1|/Ft1.3  (1)

4.0|Fr|/Ft6.0  (2)

where F1 is a focal length of the first lens, Fr is the focal length of the rear lens group, and Ft is the focal length of the total optics of the.

 
Web www.patentalert.com

< Compact projection lenses for use with large format pixelized panels

< Imaging optical system, image display apparatus and imaging optical apparatus

> Zoom lens and apparatus using the same

> Pickup lens

~ 00244