What is trifocal eyeglasses lenses? Who should use this type eyeglasses lenses? And what is the estimated price? What is the difference between trifocal eyeglasses lenses and bifocal eyeglasses lenses?

Trifocal lens, just as its name implies, it can combine a segment for near vision (lower / bottom), another for near far vision (upper), and a third one for vision at the screen distance (middle, between the far and near segments).