A multi-link hinge comprising: a cam rotatably coupled to a main body of an apparatus having a door to be rotatable on a shaft; an arm link provided at the door; an outer link having a first side portion rotatably coupled to the cam and a second side portion rotatably coupled to the arm link; an inner link provided at a lower portion of the outer link and having a first side portion rotatably coupled to the main body and a second side portion rotatably coupled to the arm link; a connection link having a first side portion rotatably coupled to the cam and a second side portion rotatably coupled to the inner link, and configured to transmit a force rotating the inner link in a direction opposite to a rotating direction of the cam; and an elastic member provided at a lower portion of the cam, and having a first side portion rotatably coupled to the main body and a second side portion rotatably coupled to the cam, and configured to provide a pushing force toward the cam to push the cam so as to rotate it clockwise in response to a door opening motion and to push the cam so as to rotate it counterclockwise in response to a door closing motion, characterized in that the multi-link hinge further comprises a tray driving part wherein the tray driving part is configured to operate a tray in conjunction with the door motions, wherein the tray is configured to slide into and out of the main body, and wherein a cam profile is formed on an outer circumferential surface of the cam, and wherein a tray driving cam profile includes a concave portion and a convex portion wherein the tray driving cam profile is defined as a portion between a portion coupled to the outer link and a portion coupled to the elastic member, and wherein the tray driving part comprises: a connector having a first side portion rotatably coupled to the main body and a second side portion coupled to the tray; a cam link having a first side portion coupled to the connector and a second side portion connected to the cam to be rollably moved along the tray driving cam profile; and a tray spring having a first side portion coupled to the connector and a second side portion coupled to the main body, and configured to provide a force pulling the connector toward the cam. a cam rotatably coupled to a main body of an apparatus having a door to be rotatable on a shaft; an arm link provided at the door; an outer link having a first side portion rotatably coupled to the cam and a second side portion rotatably coupled to the arm link; an inner link provided at a lower portion of the outer link and having a first side portion rotatably coupled to the main body and a second side portion rotatably coupled to the arm link; a connection link having a first side portion rotatably coupled to the cam and a second side portion rotatably coupled to the inner link, and configured to transmit a force rotating the inner link in a direction opposite to a rotating direction of the cam; and an elastic member provided at a lower portion of the cam, and having a first side portion rotatably coupled to the main body and a second side portion rotatably coupled to the cam, and configured to provide a pushing force toward the cam to push the cam so as to rotate it clockwise in response to a door opening motion and to push the cam so as to rotate it counterclockwise in response to a door closing motion, characterized in that the multi-link hinge further comprises a tray driving part wherein the tray driving part is configured to operate a tray in conjunction with the door motions, wherein the tray is configured to slide into and out of the main body, and wherein a cam profile is formed on an outer circumferential surface of the cam, and wherein a tray driving cam profile includes a concave portion and a convex portion wherein the tray driving cam profile is defined as a portion between a portion coupled to the outer link and a portion coupled to the elastic member, and wherein the tray driving part comprises: a connector having a first side portion rotatably coupled to the main body and a second side portion coupled to the tray; a cam link having a first side portion coupled to the connector and a second side portion connected to the cam to be rollably moved along the tray driving cam profile; and a tray spring having a first side portion coupled to the connector and a second side portion coupled to the main body, and configured to provide a force pulling the connector toward the cam.