An antenna comprising: a substrate; an antenna area which is formed on a corner of the substrate; an antenna conductor which is formed in the antenna area and extends between a ground end and an open end, a bend being formed between the ground end and the open end, the part of the antenna conductor extending from the ground end to the bend being a first conductor part and the part of the antenna conductor extending from the bend to the open end being a second conductor part; a first ground area which is formed next to the antenna area and is connected to the ground end of the first conductor part; a second ground area which is formed next to the antenna area, an edge of the second ground area closest to the antenna area being defined by a borderline, and is spaced away from the open end of the second conductor part in a direction from the bend to the open end of the second conductor part, wherein the open end is directed towards the second ground area; and a feed unit which feeds electricity to the antenna conductor; and characterized in that: an L-shaped wave director is formed in the antenna area, having a director part and a capacitor part connected by a bend, the director part being generally parallel to the second conductor part of the antenna conductor and the capacitor part being generally parallel to the borderline between the antenna area and the second ground area; the second ground area is disposed with respect to the wave director in a longitudinal direction of the director part of the wave director so that an image of the wave director can be formed in the second ground area; a capacitor (70, 96) is formed by the capacitor part of the wave director and the second ground area; and in use, the antenna provides a higher field intensity at the open end of the antenna conductor than at the bend. a substrate; an antenna area which is formed on a corner of the substrate; an antenna conductor which is formed in the antenna area and extends between a ground end and an open end, a bend being formed between the ground end and the open end, the part of the antenna conductor extending from the ground end to the bend being a first conductor part and the part of the antenna conductor extending from the bend to the open end being a second conductor part; a first ground area which is formed next to the antenna area and is connected to the ground end of the first conductor part; a second ground area which is formed next to the antenna area, an edge of the second ground area closest to the antenna area being defined by a borderline, and is spaced away from the open end of the second conductor part in a direction from the bend to the open end of the second conductor part, wherein the open end is directed towards the second ground area; and a feed unit which feeds electricity to the antenna conductor; and characterized in that: an L-shaped wave director is formed in the antenna area, having a director part and a capacitor part connected by a bend, the director part being generally parallel to the second conductor part of the antenna conductor and the capacitor part being generally parallel to the borderline between the antenna area and the second ground area; the second ground area is disposed with respect to the wave director in a longitudinal direction of the director part of the wave director so that an image of the wave director can be formed in the second ground area; a capacitor (70, 96) is formed by the capacitor part of the wave director and the second ground area; and in use, the antenna provides a higher field intensity at the open end of the antenna conductor than at the bend. an L-shaped wave director is formed in the antenna area, having a director part and a capacitor part connected by a bend, the director part being generally parallel to the second conductor part of the antenna conductor and the capacitor part being generally parallel to the borderline between the antenna area and the second ground area; the second ground area is disposed with respect to the wave director in a longitudinal direction of the director part of the wave director so that an image of the wave director can be formed in the second ground area; a capacitor (70, 96) is formed by the capacitor part of the wave director and the second ground area; and in use, the antenna provides a higher field intensity at the open end of the antenna conductor than at the bend.