Hi @swei1215, thanks for your query. Yes, Tobii Ocumen provides fixation filters (more info @ https://developer.tobii.com/xr/develop/ocumen/filter-documentation/) which include Saccade detection.
The time threshold using the G20M algorithm is not set but determined via the Machine learning algorithm of the G20M.
For information on pricing for Tobii Ocumen please fill out your contact details @ https://developer.tobii.com/xr/contact/