SUBPICOMETER ACCURACY LASER WAVELENGTH SENSOR USING MULTIPLEXED BRAGGGRATINGS

Wavelength-and angle-multiplexed holographic Bragg gratings are used a s a highly sensitive wavelength sensor, An absolute wavelength accurac y as high as 0.3 pm has been demonstrated with gratings recorded in an Fe-doped LiNbO3 photorefractive crystals of dimension of 5 x 5 x 4 (m m(3)), This technique provides a simple and accurate solution to laser wavelength measurement in applications such as wavelength-division mu ltiplexed (WDM) fiber-optic networks, precision interferometry, Dopple r spectroscopy, and others.