my iPad won't connect to Apple TV
I have updated latest software on iMac, iPad, iPod and Apple TV, and also reset the Apple TV. I now find that I cannot connect either the iPod or iPad to Apple TV. Where you would expect the Apple TV icon to appear on iPod or iPad screen, it doesn't. Previously, before all of the upgrades it all worked perfectly.
Help please
iPad 2, iOS 6.1.2