POLARIZED LIGHT SEPARATING ELEMENT AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To obtain a polarized separating element capable of suppressing the evaporation of carboxylic acid contained in a transparent phase obtained after exposing a pattern to ultraviolet rays and preventing or suppressing the generation of dents on the transparent phase. SOLUTION: The polarized light separating element has a glass substrate 10. A periodical grating 12 consiting of a poly-diacetylene derivative film 11 is formed on the surface of the substrate 10. The grating 12 is formed by selectively irradiating the film 11 with ultraviolet rays. The hue of the 1st hue changing part 121 of the grating 12 is changed to a transparent phase. Volatile carboxylic acid generated by the 1st hue changing part 121 based on ultraviolet irradiation is chelated by calcium ions. Thus the evaporation of the carboxylic acid with the lapse of time can be suppressed. Consequently the polarized light separating element can prevent or suppress the generation of dents on the 1st hue changing part and stabilize the diffraction characteristics of the grating 12.