I think around 3-3.5 months a baby would be able to see, but you'd do better to search for that type of info on the web.
I found this sight:
http://www.ski.org/Vision/babyvision.htmlBut didn't look through it, but it looks like a great starting place.
Best of luck, enjoy your bucket of joy!
P.S. I know that it's typically *bundle*, but I wanted to try something new