Vision enhancers are built into his mask

"Lord Vader, the skiff is positioning a hyperdrive booster in the CloakShape's flight path." The vision enhancers built into Vader's mask delivered a close-up of the red-and-white hypermatter ring. Quickly he thumbed the triggers on the steering yoke, and a hail of crimson bolts streaked from the interceptor's long-barreled laser cannons. But it was unlikely that the bolts would ever reach their targets, because the targets would be long gone.

Dark Lord: The Rise of Darth Vader, Part II, Page 115