Here's a great catching drill that catchers can use to improve their vision.  It is a vision drill as well as a catching drill, but can help catchers improve vision in each individual eye as well as work on depth perception and dynamic vision one eye at a time.

Catching Drills - Single Eye Vision Drill for Catchers

Check out Major League catcher Omir Santos performing this great catching drill which is also a vision drill. He shuts one eye and tries to catch the small balls in different locations, then opens that eye and shuts the other and repeats. This is a great catching drill and as you can see, Major League catchers do it, so you know it's a good catching drill or vision drill.