Optical fiber communication method and transmitting device

#This application claims priority of Taiwanese Application No. 098141527, filed on Dec. 4, 2009.

#1. Field of the Invention

#This invention relates to an optical fiber communication method and a transmitting device, more particularly to an optical fiber communication method and a transmitting device using a second-order fiber Bragg grating structure.

#Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments of this invention, with reference to the accompanying drawings, in which:

#FIG. 1 is a schematic diagram illustrating a transmitting device according to the first preferred embodiment of this invention;

#FIG. 2 is a schematic diagram illustrating an application of the transmitting device of FIG. 1;

#Before the present invention is described in greater detail with reference to the accompanying preferred embodiments, it should be noted herein that like elements are denoted by the same reference numerals throughout the disclosure.

#Referring to FIGS. 1 and 2, a transmitting device 7 according to the first preferred embodiment of this invention includes a converting unit 71, a first optical fiber 72, a second optical fiber 73, a first light guide unit 74, and a second light guide unit 75.

#Each of the first and second optical fibers 72, 73 includes a core 721, 731 that is provided with at least one second-order Bragg grating structure 723, 733, and a cladding 722, 732 that surrounds the core 721, 731. The second-order Bragg grating structure 723 of the first optical fiber 72 has a periodically varying refractive index that varies according to a first period and that defines a first effective refractive index, and permits transmission, via radiation, of a signal with a wavelength that falls within a first predetermined wavelength range, which is determined according to a product of the first period and the first effective refractive index. The second-order Bragg grating structure 732 of the second optical fiber 73 has a periodically varying refractive index that varies according to a second period and that defines a second effective refractive index, and permits transmission, via radiation, of a signal with a wavelength that falls within a second predetermined wavelength range, which is determined according to a product of the second period and the second effective refractive index. Preferably, the first and second optical fibers 72, 73 are photosensitive optical fibers, and the second predetermined wavelength range is different from the first predetermined wavelength range.