Battery-less spatial optical communication terminals for location-based indoor information services

Implementations of ultra low power consuming information terminals and the base stations have been developing to realize human supporting information services not only for ordinary people, but for information divided people. Spatial optical wavelength multiplexing technique at near infrared and eye-safe wavelength region was employed to serve multiple contents simultaneously. Reflectivity modulating technique using a liquid crystal light modulator and a corner-reflecting sheet was realized for uploading data with ultra low power consumption