A passband-flattened acousto-optic filter

Author

Jackel, Janet L. ; Baran, Jane E. ; D´Alessandro, Antonio ; Smith, David A.

Author_Institution

Bellcore, Red Bank, NJ, USA

Volume

7

Issue

3

fYear

1995

fDate

3/1/1995 12:00:00 AM

Firstpage

318

Lastpage

320

Abstract

We have demonstrated a passband-flattened LiNbO/sub 3/ guided-wave acousto-optic tunable filter (AOTF). Passband flattening is achieved by approximating the predicted flattened-filter decaying-sine acoustic intensity drive function by two half cycles of a sine wave of successively lower intensity. These filters have a cross-state 3-dB passband of /spl sim/1.75 nm, equal to that of the apodized filters on which they are based, an approximately 1 nm wide flat region with <0.5 dB variation of transmission, and correspondingly broadened depletion in the bar state, with a maximum rejection ratio of better than 17 dB. Worst-case sidelobes are /spl sim/13 dB. The typical acoustic power required for complete switching is 40 mW, only 20-40% greater than that needed in the apodized filter.<>

Keywords

acousto-optical filters; band-pass filters; lithium compounds; optical communication equipment; optical fibre communication; optical images; optical waveguides; tuning; 40 mW; LiNbO/sub 3/ guided-wave acousto-optic tunable filter; acoustic power; apodized filters; complete switching; cross-state 3-dB passband; flattened-filter decaying-sine acoustic intensity drive function; maximum rejection ratio; passband-flattened acousto-optic filter; sine wave; worst-case sidelobes; Acoustic waveguides; Acoustic waves; Communication switching; Crosstalk; Optical filters; Optical waveguides; Passband; Shape; Surface acoustic waves; Switches;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/68.372758

Filename

372758