A variable power finder is proposed, which comprises: an objective system; an
inverting
system; and an ocular system, in order from object side. The third lens group of
the objective system is constituted by one lens prism having at least one reflection
surface, and following expressions are satisfied:
f3/fw2.5 (1)
-1.0(R32+R31)/(R32-R31)1.0 (2)
L1/fw20.45 1/mm (3)
L2/fw20.03 1/mm (4)
where f3 is a focal distance of in millimeters (mm) third lens group,
fw is a focal distance in mm at wide angle end of objective system, R31
is a curvature radius of object side lens surface of lens prism, R32 is
a curvature radius of image side lens surface of lens prism, L1 is an air
equivalent distance in mm from middle imaging surface to object side lens surface
of lens prism, and L2 is a distance in mm from middle imaging surface to
image side lens surface of lens prism.