Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

We present a technique to measure the refractive index profile of direct laser written waveguides. This method has the potential for straightforward implementation in an existing laser fabrication system. Quantitative phase microscopy, based on the Transfer of Intensity equation, is used to analyse waveguides fabricated with an ultrashort pulsed laser embedded several hundred micron below the surface of fused silica. It is shown that the cumulative phase change induced by the waveguide perpendicular to its axis may be monitored in real-time during the fabrication process. Results are verified through comparison with interferometry. Tomographic measurements using illumination from a high numerical aperture condenser lens are used to infer the waveguide cross-section. Results are compared with measurements of the waveguide cross-section from a third harmonic generation microscope. © 2013 Optical Society of America.

Original publication

DOI

10.1364/OME.3.001223

Type

Journal article

Journal

Optical Materials Express

Publication Date

20/09/2013

Volume

3

Pages

1223 - 1232