A field emission element (100) includes an elongated solid body (110), a
carbon nanotube yarn (112) and an electrically conductive adhesive agent
(114). The carbon nanotube yarn wraps round the elongated solid body. The
electrically conductive adhesive agent is applied between the elongated
solid body and the carbon nanotube yarn, and the electrically conductive
adhesive agent is configured for fixing the carbon nanotube yarn to the
elongated solid body. The substantially all of carbon nanotube yarn is
entirely adhered on a peripheral surface of the elongated solid body.