The gravitational lensing effects in the weak gravitational field by exotic lenses have been investigated intensively to find nonluminous exotic objects .
Gravitational lensing based on 1 / r ^ { n } fall-off metric , as a one-parameter model that can treat by hand both the Schwarzschild lens ( n=1 ) and the Ellis wormhole ( n=2 ) in the weak field , has been recently studied .
Only for n = 1 case , however , it has been explicitly shown that effects of relativistic lens images by the strong field on the light curve can be neglected .
We discuss whether relativistic images by the strong field can be neglected for n > 1 in the Tangherlini spacetime which is one of the simplest models for our purpose .
We calculate the divergent part of the deflection angle for arbitrary n and the regular part for n = 1 , 2 and 4 in the strong field limit , the deflection angle for arbitrary n under the weak gravitational approximation .
We also compare the radius of the Einstein ring with the radii of the relativistic Einstein rings for arbitrary n .
We conclude that the images in the strong gravitational field have little effect on the total light curve and that the time-symmetric demagnification parts in the light curve will appear even after taking account of the images in the strong gravitational field for n > 1 .