Two-photon image-scanning microscopy with SPAD array and blind image reconstruction
: Sami V. Koho, Eli Slenders, Giorgio Tortarolo, Marco Castello, Mauro Buttafava, Federica Villa, Elena Tcarenkova, Marcel Ameloot, Paolo Bianchini, Colin J. R. Sheppard, Alberto Diaspro, Alberto Tosi, Giuseppe Vicidomini
Publisher: OPTICAL SOC AMER
: 2020
: Biomedical Optics Express
: BIOMEDICAL OPTICS EXPRESS
: BIOMED OPT EXPRESS
: 11
: 6
: 2905
: 2924
: 20
: 2156-7085
DOI: https://doi.org/10.1364/BOE.374398
: https://research.utu.fi/converis/portal/detail/Publication/48978703
Two-photon excitation (2PE) laser scanning microscopy is the imaging modality of choice when one desires to work with thick biological samples. However, its spatial resolution is poor, below confocal laser scanning microscopy. Here, we propose a straightforward implementation of 2PE image scanning microscopy (2PE-ISM) that, by leveraging our recently introduced single-photon avalanche diode (SPAD) array detector and a novel blind image reconstruction method, is shown to enhance the effective resolution, as well as the overall image quality of 2PE microscopy. With our adaptive pixel reassignment procedure similar to 1.6 times resolution increase is maintained deep into thick semi-transparent samples. The integration of Fourier ring correlation based semi-blind deconvolution is shown to further enhance the effective resolution by a factor of similar to 2 - and automatic background correction is shown to boost the image quality especially in noisy images. Most importantly, our 2PE-ISM implementation requires no calibration measurements or other input from the user, which is an important aspect in terms of day-to-day usability of the technique. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement