Singapore is the first country to be allowed to use this Auto Gate at Suvarnabhumi airport. The Immigration Bureau of Thailand will consider adding other countries to the list for the Auto Gate in the near future.
Singapore travellers who wish to use the Auto Gate do not need to do preliminary register with the Thai immigration office. At the Auto Gate, the system will record passenger information and fingerprints for identification on subsequent trips. It can also be linked to airlines’ check-in systems to verify passengers’ identities.
Note that, currently, the Auto Gate access only applies for Singaporeans entering Thailand for tourism (not business) purposes.
Read more at http://www.channelnewsasia.com/news/singapore/singaporeans-can-use-passport-scanners-at-thailand-s-9139338