On a lightly floured work surface, roll out the puff pastry to a 14 1/2-inch square about 1/8 inch thick. Using a sharp knife, cut the pastry into 8 squares. Spoon the pear filling onto a corner of each square, leaving a 1/2-inch border. Fold the pastry over the filling to make a triangle and firmly press the edges to seal. Crimp the edges with a fork. Prick each triangle once with the fork to allow steam to escape during baking. Transfer the turnovers to a baking sheet and refrigerate for at least 30 minutes, until chilled.