We have developed a linear horizontal wedge field emission cathode for field emission displays. The cathode consists of a horizontal wedge with a diameter of curvature ∼10 nm. A self-aligned sloping gate is positioned at a distance of ∼10 nm above the wedge. Computer simulation shows that the wedge cathode can operate at a gate voltage of ⩽15 V to allow the use of complementary metal–oxide semiconductor drivers to modulate the electron emission. Coplanar focusing electrodes are incorporated without additional processing steps to collimate the electron beam to a dimension of ∼50 μm onto a high voltage phosphor screen ∼1 mm away. We have fabricated wedge cathodes operating at a gate voltage of ∼60 V with a relatively uniform emission from an area of ∼5 mm×5 mm. The wedge cathode was developed to be fabricated with mainstream large-area equipment for flat panel displays.