A larger picture would be nice! I'm guessing 1948-1949 not 1946.
http://i.ebayimg.com/10/!B2+guJwCWk~$%28KGrHqQOKnEE%295bCcjpyBMkl3PqO+Q~~_ 35.JPG

http://cgi.ebay.com/antique-1946-Emerson-TV-/290476397528

Hard to tell if that's dirt or blown phosphor on the face of that tube.

1950-51, and I think it's just dirt. It would be nice if there was something more than a thumbnail to go on though.