Precise wavelength demodulator used for fiber sensitivity

Shiya He; Tiecheng Guo; Shuyang Hu; Wei Liu; Kuanxin Yu

doi:10.1117/12.782901

21 November 2007 Precise wavelength demodulator used for fiber sensitivity

Shiya He, Tiecheng Guo, Shuyang Hu, Wei Liu, Kuanxin Yu

Proceedings Volume 6724, 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems; 67241L (2007) https://doi.org/10.1117/12.782901
Event: 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, 2007, Chengdu, China

Abstract

Wavelength encoding sensors, such as fiber Bragg grating, have the advantage of strong antijamming ability. However, the wavelength encoding signal is usually converted to electric intensity signal by demodulators in most measurements. The intensity signal is easy to be disturbed by environmental factors, so the advantage of wavelength encoding fails due to the instable intensity demodulation. In this paper, a novel wavelength demodulating method is presented. This method demodulates wavelength encoding signal directly by means of counting using a Sagnac interferometer with birefringent fiber without encoding conversion from wavelength to intensity. Through the interferometer, the changed wavelength signal from sensor becomes the kind of output light, the intensity of which is changed with wavelength periodically. The intensity can easy be disturbed, but its period is very stable. In other words, the change of wavelength in one intensity period is stable. With this character, we count the number at the rising edge and falling edge of intensity appear, and then calculate the accurate change of wavelength signal. From experiment, we get 0.067 nm wavelength resolution by use of a Sagnac interferometer with 30 meter birefringent fiber. It is proved that the intensity frequency (the reciprocal of intensity period) changed with wavelength is proportional to the length of birefringent fiber. If the length is fixed, the frequency is determined. For farther increase of wavelength resolution, it is only necessary to increase the length of birefringent fiber. The wavelength demodulator is characteristic of high stability and high precision.

Citation Download Citation

Shiya He, Tiecheng Guo, Shuyang Hu, Wei Liu, and Kuanxin Yu "Precise wavelength demodulator used for fiber sensitivity", Proc. SPIE 6724, 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, 67241L (21 November 2007); https://doi.org/10.1117/12.782901

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
6 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Fiber Bragg gratings

Computer programming

Demodulation

Sagnac interferometers

Sensors

Spectrum analysis

Polarization

Show All Keywords

Keywords/Phrases

Search In:

Publication Years