DIFFRACTIVE OPTICAL ELEMENT CAPABLE OF BEING USED FOR PROJECTING OBLIQUE LINE, PROJECTION APPARATUS, AND DESIGN METHOD THEREFOR

摘要

Provided is a design method for a diffractive optical element capable of being used for projecting an oblique line. The method comprises: determining an angle θ between an oblique line and a first direction (S101); according to the angle, determining a first period d1 of a diffractive optical element in the first direction and a second period d2 of the diffractive optical element in a second direction, wherein the first direction is perpendicular to the second direction, and the first period d1 and the second period d2 satisfy tgθ = d1/d2 (S102); and obtaining a phase distribution map of the diffractive optical element according to the first period d1, the second period d2 and a target map with an oblique line at 45 degrees (S103). By means of the design method, the visual effect of an optical field projected by means of a diffractive optical element can be improved.