{'fraction_non_alphanumeric': 0.022590361445783132, 'fraction_numerical': 0.0015060240963855422, 'mean_word_length': 5.0963302752293576, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Tapered Fibers for Optogenetics: Gaining Spatial Resolution in Deep Brain Regions by Exploiting Angle-Selective Light Injection Systems

This work describes a method to inject light into tapered optical fibers (TFs) in order to achieve site-selective and wide-volume optical control of neural activity with a single optical setup. The method relies on a Galvanometric – Resonant mirrors scan head, employed to inject light into the fiber to: (i) select a specific subset of guided modes obtaining localized illumination or (ii) to scan between the different guided modes at high-rate to obtain full NA-like light injection on time scales >0.2 ms. This is shown by analysing the light emission profiles from the TF with different voltage biases applied to the Galvanometric and the Resonant mirrors, and comparing them with a standard Full NA light-injection. With the aim to find the experimental parameters to obtain efficient Full NA – like emission profile, the Emission Length and the First Emission Diameter of TFs were extracted and compared with an ideal wide-volume emitter. Both Galvanometric and Resonant scanners methods shown a good agreement with the reference values of the standard Full NA injection, allowing neuroscientists to switch from site-selective to wide-volume illumination using a single optical setup.