This is an innovative solution that prevents the pain at the back of the neck that usually results from reading books placed on flat table. A book to be read placed on a flat table requires that the head and neck be bent over to get a clear view of the notes. Hence, after some time, pain develops at the back of the neck.
If the book can be placed upright, the head and neck can be kept straight and the back can be rested against the chair, then, studying can be more comfortable.