Patent ID: 6195483
Filing Date: 2001-02-27
Classification: G02B

Abstract:
A method of fabricating at least two reflective Bragg gratings in the interior of an infrared transmitting glass fiber, said method comprising the steps of:(a) producing first and second writing beam lines at the same wavelength;(b) orienting the first and second writing beam lines in parallel with respect to each other;(c) crossing the first and second writing beam lines at a preselected angle with respect to each other to form an interference pattern at the intersection of the first and second writing beam lines;(d) positioning a first part of the infrared transmitting glass fiber at the intersection of the first and second writing beam lines so that the interference pattern occurs along a first portion of the length of the infrared transmitting glass fiber;(e) maintaining the first part of the infrared transmitting glass fiber at the intersection of the first and second writing beam lines for a time sufficient to produce a first Bragg grating in the core and of the infrared transmitting glass fiber;(f) positioning a second part of the infrared transmitting glass fiber at the intersection of the first and second writing beam lines so that the interference pattern occurs along a second portion of the length of the infrared transmitting glass fiber; and(g) maintaining the second part of the infrared transmitting glass fiber at the intersection of the first and second writing beam lines for a time sufficient to produce a second Bragg grating in the core and cladding of the infrared transmitting glass fiber;wherein the wavelength of the first and second writing beams is within the range from about 0.5 .mu.m to about 1.5 .mu.m in order to produce a Bragg reflection wavelength in the range between 1.5 .mu.m to about 15 .mu.m.