Developing ultrafast laser inscribed volume gratings

David Guillaume MacLachlan, Debaditya Choudhury, Alexander Arriola, Colin Cunningham, Robert R. Thomson, Andrew Kirkham, David Lee

Research output: Chapter in Book/Report/Conference proceedingConference contribution

4 Citations (Scopus)

Abstract

Due to their high efficiency and broad operational bandwidths, volume phase holographic gratings (VPHGs) are often the grating technology of choice for astronomical instruments, but current VPHGs exhibit a number of drawbacks including limits on their size, function and durability due to the manufacturing process. VPHGs are also generally made using a dichromated gelatine substrate, which exhibits reduced transmission at wavelengths longer than similar to 2.2 mu m, limiting their ability to operate further into the mid-infrared.

An emerging alternative method of manufacturing volume gratings is ultrafast laser inscription (ULI). This technique uses focused ultrashort laser pulses to induce a localised refractive index modification inside the bulk of a substrate material. We have recently demonstrated that ULI can be used to create volume gratings for operation in the visible, near-infrared and mid-infrared regions by inscribing volume gratings in a chalcogenide glass. The direct-write nature of ULI may then facilitate the fabrication of gratings which are not restricted in terms of their size and grating profile, as is currently the case with gelatine based VPHGs.

In this paper, we present our work on the manufacture of volume gratings in gallium lanthanum sulphide (GLS) chalcogenide glass. The gratings are aimed at efficient operation at wavelengths around 1 mu m, and the effect of applying an anti-reflection coating to the substrate to reduce Fresnel reflections is studied.

Original languageEnglish
Title of host publicationAdvances in Optical and Mechanical Technologies for Telescopes and Instrumentation
EditorsR Navarro, CR Cunningham, AA Barto
Place of PublicationBellingham
PublisherSPIE
Number of pages6
DOIs
Publication statusPublished - 2014
EventConference on Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation - Montreal, Canada
Duration: 23 Jun 201427 Jun 2014

Publication series

NameProceedings of SPIE
PublisherSPIE
Volume9151
ISSN (Print)0277-786X

Conference

ConferenceConference on Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation
CountryCanada
Period23/06/1427/06/14

Keywords

  • Diffraction grating
  • volume phase holographic gratings
  • ultrafast laser inscription
  • chalcogenide
  • FEMTOSECOND LASER
  • FUSED-SILICA
  • GLASS
  • FABRICATION
  • PULSES
  • EFFICIENCY

Cite this

MacLachlan, D. G., Choudhury, D., Arriola, A., Cunningham, C., Thomson, R. R., Kirkham, A., & Lee, D. (2014). Developing ultrafast laser inscribed volume gratings. In R. Navarro, CR. Cunningham, & AA. Barto (Eds.), Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation [91511H] (Proceedings of SPIE; Vol. 9151). SPIE. https://doi.org/10.1117/12.2055882