In situ and real time monitoring of two-photon polymerization using broadband coherent anti-Stokes Raman scattering microscopy

Technology and Applications Center, Newport Corporation, 1791 Deere Avenue, Irvine, CA 92606, USA.
Optics Express (Impact Factor: 3.49). 08/2010; 18(18):19219-31. DOI: 10.1364/OE.18.019219
Source: PubMed


We demonstrate in situ and real time characterization of two-photon polymerization (TPP) by means of broadband coherent anti-Stokes Raman scattering (CARS) microscopy. The same experimental setup based on one femtosecond oscillator is used to perform both TPP and broadband CARS microscopy. We performed in situ imaging with chemical specificity of three-dimensional microstructures fabricated by TPP, and successfully followed the writing process in real time. Broadband CARS microscopy allowed discerning between polymerized and unpolymerized material. Imaging with good vibrational contrast is achieved without causing any damage to the microstructures or undesired polymerization within the sample.

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    • "In this study, broadband CARS microscopy based on a photonic crystal fiber light source has been used to measure microalgal cells. A wavelength extension unit (WEU) from Newport was used in this study [44]. Although a full description of the WEU can be found elsewhere [44], a short account on the most critical parts of this unit is described here. "
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    • "Recently, SRS has superseded CARS as a contrast mechanism for microscopy, because it has improved sensitivity, no image artifacts from spectral distortions or coherent signal addition, and a linear concentration dependence. There has also been increasing interest in using CRS microscopy for medical diagnostics [4], as well as practical applications outside the field of biological and medical applications, such as studies of two-photon polymerization reaction and mechanical properties of polymer microstructures [5]. "
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