According to the US Navy:
U.S. Navy Fact Sheet: Attack Submarines - SSN(in English). The US Navy (2007-11-13). Retrieved on 2008-05-15. "In Virginia class boats, traditional periscopes have been supplanted by two Photonics Masts
that house color, high-resolution black and white, and infrared digital cameras atop
telescoping arms. With the removal of the barrel periscopes, the ships’ control room has
been moved down one deck and away from the hull’s curvature, affording it more room and an
improved layout that provides the commanding officer with enhanced situational awareness."
{{Information |Description={{en|1=An image of a photonic mast array on a USS Virginia class submarine.}} |Source=http://science.howstuffworks.com/photonic-mast.htm |Author=Photo courtesy Naval Sea Systems Command |Date=2004 |Permission= |other_version