[OPTICAL REVIEW Vol. 8, No. 4 (2001) 267-270]
A Novel Fabrication Technique of Long Period Fiber Gratings Using a Holographic Optical Element
Atsushi SUGITATSU1,*, Hiroyuki KAWANO2, Tatsuo HATTA1 and Kumio KASAHARA1
1Information Technology R & D Center, Mitsubishi Electric Corp., 4-1, Mizuhara, Itami, Hyogo, 664-8641 Japan, 2Advanced Technology R & D Center, Mitsubishi Electric Corp., 8-1-1, Tsukaguchi-Honmachi, Amagasaki, Hyogo, 661-8661 Japan
(Received January 31, 2001; Accepted April 26, 2001)
We develop a new flexible and precise ultraviolet exposure technique to fabricate a long period fiber grating using a computer-generated holographic optical element (HOE). The HOE can generate a striped beam pattern with about a 300 μm period from a KrF excimer laser. This method offers (1) ease in varying the grating period and (2) grating period precision. We achieve a grating period within an accuracy of ±0.04 μm. This means that the peak wavelength can be controlled within an accuracy of ±0.2 nm with an operating wavelength of 1.55 μm.
Key words : fiber grating, long period fiber grating, computer-generated hologram, holographic optical element, excimer laser, ultrabiolet exposure