1. A foldable display device, comprising:a main body structure; and
a flexible screen on a surface of the main body structure;
wherein the main body structure includes two flat plate areas and a bending area connecting the two flat plate areas so the two flat plate areas have an opening and closing angle of 0 degrees to at least 180 degrees;
wherein the bending area includes a bending body and a bending bracket group positioned in the bending body, the bending bracket group includes three or more T-shaped brackets arranged successively, a horizontal bar of each T-shaped bracket includes two bracket arms, a vertical bar of each T-shaped bracket is a bracket body, upper surfaces of the T-shaped brackets are located on an inner side surface of the bending body, and the bracket arms of two adjacent T-shaped brackets are hinged by a first hinge; and
wherein a pivot link is positioned between the bracket bodies of any two adjacent T-shaped brackets, the pivot link includes two pivoting rods hinged together by a second hinge at one end of each of the two pivoting rods, and each of the two pivoting rods are hinged to one of the bracket bodies at the other end of said pivoting rod by a third hinge.