Abstract:
Emitted light rays from a very distant and bright source are deflected between the source and the
observer when they pass near a massive body with an enormous gravity. As a result the massive
body such as a cluster of galaxies have an ability to perform as a gravitational lens. In recent
times, some authors [1] have found that the cosmological constant , affects the phenomenon of
gravitational lensing.
In this paper, we have corrected an expression for the total deflection angle which was published
in 2008 of our first paper regarding this subject [2] . Considering the effect of the cosmological
constant, we have also found two equations for the path of a light ray when it passes near a
massive object with a very high gravitational influence.