Walter nods when Ben gets to the instruction of 'keep an eye on it', and gently touches the glasses' frames and cameras throughout the recap.

Takes a breath-

"Ready."

For a millisecond, it's almost anticlimactic; another point of light becomes available. Connecting to that, though-

His breath catches. He has to stop himself from rubbing at his eyes, both because what's in them now won't stop him from seeing, and because rubbing the glasses might be a bad idea.

Once he's sure he's seeing Ben, the first thing he does is go in for a hug.