| US 7,593,609 B2 | ||
| Method for modulating refractive indices of optical fiber gratings | ||
| Kuei Chu Hsu, Tainan County (Taiwan); and Yin Chieh Lai, Taichung (Taiwan) | ||
| Assigned to National Chiao Tung University, Hsinchu (Taiwan) | ||
| Filed on Jan. 17, 2008, as Appl. No. 12/16,081. | ||
| Claims priority of application No. 96140396 A (TW), filed on Oct. 26, 2007. | ||
| Prior Publication US 2009/0110343 A1, Apr. 30, 2009 | ||
| Int. Cl. G02B 6/34 (2006.01) | ||
| U.S. Cl. 385—37 [385/10; 430/290] | 12 Claims |
| 1. A method for modulating refractive indices of optical fiber gratings comprising:
providing an optical fiber grating having a plurality of assigned locations;
providing a first UV (Ultra-Violet) beam and a second UV beam sequentially exposing said assigned locations section by section;
and
controlling intensities and phases of said first UV beam and said second UV beam for maintaining each said assigned location
at a fixed value of a total exposure intensity exposed by said first UV beam and said second UV beam to modulate a refractive
index of said optical fiber grating,
wherein said first UV beam and said second UV beam respectively expose each said assigned location by an identical intensity;
phase differences between each said assigned location and positions where said first UV beam and said second UV beam are projected
on said optical fiber grating are respectively Δθ and −Δθ; refractive indices of said optical fiber grating are modulated
via varying said phase differences Δθ and −Δθ.
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