{'fraction_non_alphanumeric': 0.028469750889679714, 'fraction_numerical': 0.013048635824436536, 'mean_word_length': 4.943661971830986, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, '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}}
High-resolution micro-grating accelerometer based on a gram-scale proof mass.

Micro-grating accelerometer detecting small displacement by an optical system can be widely applied in inertial navigation and seismic monitoring. We proposed a micro-grating accelerometer prototype with a proof mass of gram-scale to decrease the thermal mechanical noise, which is the fundamental limit of a high-resolution accelerometer. The theoretical model for the contrast ratio of a micro-grating accelerometer is established based on Gaussian beam theory, and the adjustment method based on a scanning slit beam profiler improves the contrast ratio of 0th order effectively. Compared to our former prototype, experiment results indicate the noise floor is decreased from 0.9 mg/√Hz to 137 ng/√Hz, and the bias stability is decreased from 0.35 mg to 3.1 µg.