2018 Global RFID Innovations Technology Leadership Awards Abstract
...
'Optical RFID' is a new type of RFID technology created by fusion of visible light communication and RFID technology. Briefly, it is based on existing RFID technology, but the reader commands are transmitted using modulated LED light. Since tags are recognized only when exposed to LED light, you can select and read only the tags you want even though there are many adjacent tags.