Abstract: Methods of manufacturing optical elements such as diffraction type lenses, aspherical lenses and diffraction gratings are disclosed. Deposited on a glass substrate is a workpiece film made of a material which can be machined much more easily than the substrate. Then the workpiece film is machined to form a predetermined shape or contour therein. After forming the predetermined shape or contour in the workpiece film, the workpiece film and substrate are subjected to etching to duplicate the predetermined shape or contour formed in the workpiece film into the substrate.