{'fraction_non_alphanumeric': 0.07834101382488479, 'fraction_numerical': 0.04608294930875576, 'mean_word_length': 4.52542372881356, 'pattern_counts': {'":': 0, '<': 8, '<?xml version=': 0, '>': 8, '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}}
Mapping of Three-Dimension Optical Force Field on Micro-particle in Optical Tweezers

We use a pair of orthogonal tracking beams to track and analyze the Brownian motion of a micro-particle or a living cell trapped in optical tweezers to map the three-dimensional optical force field on these samples. For optical trapping with λ = 532nm, NA = 0.85, and total power = 100mW, the axial and the transverse spring constants are around 1x10<sup>-8</sup>N/m and 2x10<sup>-8</sup>N/m, respectively for a silica particle (diameter = 2.58 μm), and 3x10<sup>-8</sup>N/m and 2x10<sup>-7</sup>N/m, respectively for a Chinese hamster ovary cell (diameter ∼15 μm).