A display panel comprising: a substrate having an opening area, and a display area at least partially surrounding the opening area, wherein the opening area comprises a through hole formed through the substrate; a plurality of display elements arranged in the display area, each of the plurality of display elements comprising a pixel electrode, an opposite electrode, and an intermediate layer interposed between the pixel electrode and the opposite electrode; a plurality of transistors arranged in the display area, each of the plurality of transistors electrically connected to a corresponding one of the plurality of display elements; and a multilayer film characterized by the multilayer film comprising a first insulating layer arranged between the plurality of transistors and the pixel electrode and a second insulating layer arranged on the first insulating layer, the display panel further comprising: a thin film encapsulation layer covering the plurality of display elements, wherein the multilayer film comprises a first groove located between the opening area and the display area, wherein the first groove defined by a first hole of the first insulating layer and a second hole of the second insulating layer, and wherein the first groove has an undercut structure in which a lower width of the second hole of the first groove is less than an upper width of the first hole of the first groove, and each of opposite interior sides of the second insulating layer facing the second hole protrudes farther toward a center of the first groove than each of opposite interior sides of the first insulating layer facing the first hole. a substrate having an opening area, and a display area at least partially surrounding the opening area, wherein the opening area comprises a through hole formed through the substrate; a plurality of display elements arranged in the display area, each of the plurality of display elements comprising a pixel electrode, an opposite electrode, and an intermediate layer interposed between the pixel electrode and the opposite electrode; a plurality of transistors arranged in the display area, each of the plurality of transistors electrically connected to a corresponding one of the plurality of display elements; and a multilayer film the multilayer film comprising a first insulating layer arranged between the plurality of transistors and the pixel electrode and a second insulating layer arranged on the first insulating layer, the display panel further comprising: a thin film encapsulation layer covering the plurality of display elements, wherein the multilayer film comprises a first groove located between the opening area and the display area, wherein the first groove defined by a first hole of the first insulating layer and a second hole of the second insulating layer, and wherein the first groove has an undercut structure in which a lower width of the second hole of the first groove is less than an upper width of the first hole of the first groove, and each of opposite interior sides of the second insulating layer facing the second hole protrudes farther toward a center of the first groove than each of opposite interior sides of the first insulating layer facing the first hole. a thin film encapsulation layer covering the plurality of display elements, wherein the multilayer film comprises a first groove located between the opening area and the display area, wherein the first groove defined by a first hole of the first insulating layer and a second hole of the second insulating layer, and wherein the first groove has an undercut structure in which a lower width of the second hole of the first groove is less than an upper width of the first hole of the first groove, and each of opposite interior sides of the second insulating layer facing the second hole protrudes farther toward a center of the first groove than each of opposite interior sides of the first insulating layer facing the first hole.