The England midfielder spent the early part of Rafael Benitez's interim spell in charge of the club as a substitute.
However, since the turn of the year he has forced his way into Benitez's plans and has repaid the Spaniard's faith by finding the net on six occasions in all competitions.
"It's not rocket science - the more you play you get sharper and you get match fit," Lampard told the club's official website. "Since I've been able to play regularly I feel like I've got sharpness and the confidence."
Lampard's current contract at Stamford Bridge is due to expire in the summer.