meaning of "locked on"

[kjc0123]

What is the meaning of "locked on" in the following sentences?

 

"I saw the photo," Langdon said. "Your agent said Jacques Sauni�re himself did�"
"Mr. Langdon," Fache's ebony eyes locked on. "What you see in the photo is only the beginning of what Sauni�re did."

[B00]

You're really struggling with Dan Brown aint ya hon?

Locked on...as in staring, usually means to stare at someone/ something intently.

[jno]

I think it's a military metaphor - when an electronically guided missile 'locks on' to its target, meaning it sees it and electronically starts to home in on it.

[kdbug93]

Think of locked on as in "locked on a target" I'm pretty sure it means directly staring at something.