1. A multi-touch positioning method, comprising: emitting, by a first infrared ray generator set at a first angle of a display panel, infrared rays at a first wavelength, and emitting, by a second infrared ray generator set at a second angle, infrared rays at a second wavelength; receiving the infrared rays of the first wavelength and generating a first infrared ray image by a first infrared ray image sensor set at an opposite angle of the first angle, and receiving the infrared rays of the second wavelength and generating a second infrared ray image by a second infrared ray image sensor set at an opposite angle of the second angle; and performing touch point position processings for the first infrared ray image and the second infrared ray image to determine at least one touch point, comprising: performing image correction processing for the first infrared ray image and the second infrared ray image; performing analog to digital conversion for the first infrared ray image and the second infrared ray image subjected to the image correction processing, to generate a first digital image and a second digital image; performing discrimination processing for the first digital image and the second digital image, to obtain a first projection position in the first digital image of the touch point and a second projection position in the second digital image of the touch point; determining a position of the touch point according to the first projection position and the second projection position, wherein when the first angle and the second angle are adjacent angles, following processings are performed: generating a first marking position on a second diagonal according to the first projection position, and generating a second marking position on a first diagonal according to the second projection position, wherein the first diagonal is a connecting line between a vertex of the first angle and a vertex of the opposite angle of the first angle, and the second diagonal is a connecting line between a vertex of the second angle and a vertex of the opposite angle of the second angle; generating a first linear function according to a position of the vertex of the opposite angle of the first angle and the first marking position, and generating a second linear function according to a position of the vertex of the opposite angle of the second angle and the second marking position; and obtaining coordinates of the touch point according to the first linear function and the second linear function; and wherein when the first angle and the second angle are opposite angles, following processings are performed: generating a first marking position on a second diagonal according to the first projection position, and generating a second marking position on the second diagonal according to the second projection position, wherein the second diagonal is a connecting line between vertexes of two adjacent angles of the first angle; generating a first linear function according to a position of the vertex of the opposite angle of the first angle and the first marking position, and generating a second linear function according to a position of the vertex of the opposite angle of the second angle and the second marking position; and obtaining coordinates of the touch point according to the first linear function and the second linear function.