Apodisation of photo-induced waveguide gratings using double-exposure with complementary duty cycles

Xuewen Shu, Kate Sugden, Ian Bennion

Research output: Contribution to journalArticle


We present a novel apodisation scheme for photo-induced waveguide gratings. The apodisation is implemented with double exposures that have reversely varying duty cycles. We have successfully applied the proposed scheme to remove the sidelobes of long period gratings (LPGs). We also observed for the first time super strong sidelobes in LPGs when creating them with only a single varying-duty-cycle exposure. The strong sidelobes can be well explained with a Mach-Zehnder interference model.
Original languageEnglish
Pages (from-to)2221-2225
Number of pages5
JournalOptics Express
Issue number3
Publication statusPublished - 4 Feb 2008


Bibliographical note

© 2008 Optical Society of America


  • apodisation scheme
  • photo-induced waveguide gratings
  • double exposures
  • reversely varying duty cycles

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