Abstract
Ultrafast laser inscription (ULI) has been used to fabricate an 18 mm long sub-surface optical waveguide in fused silica. The waveguide started and terminated 75 mu m below the substrate surface, approaching it to a minimum depth of 6 +/- 1 mu m for the central section. The device was fabricated in a single step, exhibiting a fiber-to-fiber insertion loss of 2.6 dB. When a high refractive index oil was placed on the substrate surface, the polarization-averaged waveguide insertion loss increased by 3.7 dB. This work demonstrates that a single ULI stage can be used to fabricate optical waveguides sufficiently close to a substrate surface for evanescent field sensing applications.
Original language | English |
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Pages (from-to) | 1263-1266 |
Number of pages | 4 |
Journal | IEEE Sensors Journal |
Volume | 12 |
Issue number | 5 |
DOIs | |
Publication status | Published - May 2012 |
Keywords
- CHANNEL
- optical sensing
- FEMTOSECOND LASER
- femtosecond laser writing
- WRITTEN
- side-polished fiber
- Buried optical waveguides
- GLASS