How Many Einstein Rings Have Been Discovered?

[wolram]

How many Einstein rings have been found to date, i mean galaxies lensed by gravity?

 

[phinds]

How many Einstein rings have been found to date, i mean galaxies lensed by gravity?

So many, I think, that I seriously doubt anyone has bothered to count them.

 

[Chronos]

Gravitational lensing is a relatively rare phenomenon, but, several hundred candidate lensing events have been identified to date. The OGLE [Optical Gravitational Lensing Experiment] project has probably catalogued the majority of candidate events identified to date. See http://ogle.astrouw.edu.pl/ for further details.