It is possible to secure a sufficient depth from the normal observation to the magnification observation, has a wide angle of view at the time of ordinary observation, and further facilitates focusing at the time of magnified observation. A first lens group (G 1) having a positive optical power, a second lens group (G 2) having a negative optical power, a third lens group having a positive optical power G3), wherein the first lens group includes, in order from the object side to the image side, a first lens (L1) having negative optical power and a second lens (L2) having positive optical power , And the second lens group is moved with respect to a change in the object distance to be in focus to satisfy the following conditional expressions (1) and (2). -19 2 / f 1 <-3.5 (1) 0.5
