An organic electroluminescent display substrate, comprising: a substrate ; a display region ; a transitional region ; a packing film that extends from the display region to the transitional region ; and a through hole ; wherein the transitional region is between the display region and the through hole ; wherein the display region includes: an insulating layer on the substrate ; and an organic electroluminescent component on the insulating layer; whereby the transitional region includes: a recessed portion defined through the insulating layer in a direction perpendicular to the substrate ; wherein at least one part of the recessed portion has one side away from the substrate and another side adjacent the substrate ; the one side away from the substrate has an opening size not greater than an opening size of the another side adjacent the substrate ; and a redundant layer on the substrate and in the recessed portion ; wherein the redundant layer and at least one layer of the organic electroluminescent component are made of the same material, and the redundant layer is disconnected from the organic electroluminescent component; wherein the packing film covers the organic electroluminescent component and at least one part of the recessed portion ; and wherein the through hole extends through the packing film , the redundant layer and the substrate in a region where the recessed portion is located. a substrate ; a display region ; a transitional region ; a packing film that extends from the display region to the transitional region ; and a through hole ; wherein the transitional region is between the display region and the through hole ; wherein the display region includes: an insulating layer on the substrate ; and an organic electroluminescent component on the insulating layer; whereby the transitional region includes: a recessed portion defined through the insulating layer in a direction perpendicular to the substrate ; wherein at least one part of the recessed portion has one side away from the substrate and another side adjacent the substrate ; the one side away from the substrate has an opening size not greater than an opening size of the another side adjacent the substrate ; and a redundant layer on the substrate and in the recessed portion ; wherein the redundant layer and at least one layer of the organic electroluminescent component are made of the same material, and the redundant layer is disconnected from the organic electroluminescent component; wherein the packing film covers the organic electroluminescent component and at least one part of the recessed portion ; and wherein the through hole extends through the packing film , the redundant layer and the substrate in a region where the recessed portion is located. a recessed portion defined through the insulating layer in a direction perpendicular to the substrate ; wherein at least one part of the recessed portion has one side away from the substrate and another side adjacent the substrate ; the one side away from the substrate has an opening size not greater than an opening size of the another side adjacent the substrate ; and a redundant layer on the substrate and in the recessed portion ; wherein the redundant layer and at least one layer of the organic electroluminescent component are made of the same material, and the redundant layer is disconnected from the organic electroluminescent component; wherein the packing film covers the organic electroluminescent component and at least one part of the recessed portion ; and wherein the through hole extends through the packing film , the redundant layer and the substrate in a region where the recessed portion is located. <EOS>