Tunable optical filter ford wavelength division multiplexing using dynamic interband photorefractive gratings

摘要

We demonstrate a narrow-bandwidth tunable optical filter in the telecommunication wavelength region near 1550 nm using dynamic holography. A thick holographic reflection grating is produced in a pure potassium niobate crystal with interband photorefractive effects. The filter is tuned by changing the grating spacing by means of an acousto-optic deflector. High wavelength selectivity with a 3 dB channel bandwidth of 0.13 nm is achieved. Tuning times are in the order of a few hundred microseconds. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 21]