Why does Tobi have a Sharingan with Kamui ability after having used Izanagi? As per my understanding, Izanagi permanently blinds the Sharingan's vision once used. Tobi (Obito) donated one eye to Kakashi, and used Izanagi with the other eye to escape from Konan's paper bombs. This means he should only have a Rinnegan now, but why does he still have a Sharingan with Kamui ability? 

Note: I do not read manga.
Tobi assisted Itachi in the Uchiha clan massacre, and collected several Sharingan eyes of the dead Uchiha clan members. He must have implanted one of these Sharingan eyes in his left eye socket. 

During the battle with Konan, he has two Sharingan eyes. He did not use his original right eye for the Izanagi, but the left eye, which can be seen "losing its light" (closing) as he is talking to Konan. See images below (taken from Chapter 510).