Grating element, light wavelength selection utilizing the same, and optical signal transmitting system

摘要

A core section (10a) is formed in an optical fiber (10) made of a glass material and, electrodes (14a and 14b) are inserted into the clad section (10b) of the fiber (10). When the core section (10a) is irradiated with ultraviolet rays in prescribed intensity patterns while a high voltage is applied to the electrodes (14a and 14b), a grating section (16) in which non linear areas (16a) and normal areas(16b) are alternately formed is formed in the section (10a). The characteristics of the grating section (16) can be changed by utilizing an electrooptic effect by impressing a prescribed electric field upon the section (16) through the electrodes (14a and 14b). A grating element constituted in such a way can be utilized as an optical functional element, such as the wavelength switch, because the Bragg wavelength of the element changes when a voltage is applied.