Patent ID: 6353504
Filing Date: 2002-03-05
Classification: G02B

Abstract:
An endoscope objective lens comprising, successively from an object side, a first lens group having a negative refracting power, a second lens group having a positive refracting power, a third lens group having a negative refracting power, and a fourth lens group having a positive refracting power; wherein two lens groups consisting of said third lens group and one of said second and fourth lens groups are moved along an optical axis so as to change magnification and carry out focusing; said endoscope objective lens further satisfying the following conditional expressions (1) and (2):2.01T/&bgr;1W<10.0â€ƒâ€ƒ(1) 1.2T/fWâ€ƒâ€ƒ(2) where&bgr;1T is the magnification of the first lens group at the telephoto end; &bgr;1W is the magnification of the first lens group at the wide end; fT is the focal length of the whole lens at the telephoto end; and fW is the focal length of the whole lens at the wide end.