Display panel and manufacturing method thereof, display device and splicing display device

A manufacturing method of a display panel, comprising:

• providing a backplane;
• wherien the backplane includes a first surface and a second surface opposite to each other, and at least one side surfaces connecting the first surface and the second surface;
• forming at least one connection lead(s) on the backplane;
• wherein the connection lead extends from the first surface to the second surface via a side surface in the at least one side surface;
• the connection lead includes a first lead segment located on the first surface, a second lead segment located on the second surface and a third lead segment connecting the first lead segment and the second lead segment, and the third lead segment is located on the side surface;
• and
• forming a first protective layer;
• wherein the first protective layer covers at least the first lead segment and the third lead segment;
• at least one opening is disposed in the first protective layer, and at least a portion of the second lead segment is exposed by an opening in the at least one opening;
• the at least a portion of the second lead segment exposed by the opening is configured to be connected to a circuit board.