pureLiFi uses both visible and invisible light (InfraRed) for communications. For example our Light Antenna ONE, the LiFi@Home system and the LiFi Cube system all use Infrared for communications. Therefore no illumination is required for these LiFi access points to transmit data.
For systems such as LiFi-XC and the Kitefin System that use visible light for communications, they require some amount of illumination to transmit data.
If all power to a light is turned off then there is no LiFi. However, LiFi technology can be enabled to dim low enough that a room will appear dark and still transmit data. There is a consistent performance between 10 and 90 percent illumination.
Currently, pureLiFi’s LiFi-XC for example provides communications at light levels down to 60 lux. For comparison, the British standard for minimum light level for reading is 400 lux.