POLARIZATION INVERSION STRUCTURE MANUFACTURING METHOD, OPTICAL DEVICE MANUFACTURING METHOD, ELECTRODE FOR INVERSION, AND ELECTROOPTIC CRYSTAL SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To solve the problem in which: in an optical device having periodic polarization inversion structures arranged in multiple stages in the longitudinal direction, a desired optical device character cannot be obtained because unevenness occurs in an applied electric field due to the difference of periods of the plurality of periodic polarization inverse structures and even periodic polarization inversion structure cannot be formed.SOLUTION: The shape of an electrode for inversion 361 is made into a shape of being arranged in the longitudinal direction so that the center line of a second electrode region 364 in the arrangement direction of the electrode for inversion 361 overlaps with part of the center line of a first electrode region 363 in the arrangement direction of the electrode for inversion 361. This can prevent swelling from occurring at polarization inversion sections 321. In addition, if swelling occurs at the polarization inversion sections 321, the swelling occurs symmetrically in the arrangement direction at each of the polarization inversion sections 321; therefore, deterioration in diffraction characteristic due to bilateral asymmetry can be prevented.SELECTED DRAWING: Figure 14