A hinge apparatus includes a substantially cylindrical holder having at least one guide hole with a predetermined degree slope that extends in a longitudinal direction. A hinge shaft includes a substantially cylindrical surface configured to linearly move in the longitudinal direction of the holder. A guide pin has an end located inside the guide hole and is configured to extend through the cylindrical surface of the hinge shaft. Therefore, when the hinge shaft moves linearly in the holder, the guide pin moves along the guide hole so that the hinge shaft rotates in the holder.