At train stations and in stores, wherever there are people gathering, there will be needs for people to access all kinds of information. But information on signs is limited to only when eyes can see. Now, we are coming in a new world in which "anyone can instantaneously receive the information they need in the language they use," by putting information inside the light from the light fixtures, show windows and digital displays those equipment is so common in those areas and enables light to carry information directly to smart phones.
Display Information on a Smart Phone, Simply by Holding it up
The Light ID technology developed by Panasonic has demonstrated "visible light transmission technology," which enables to transmit any kind of information by high-speed and invisible flashing of an LED light source. Utilizing a dedicated app and their smart phone's built-in image sensor, users receive ID codes (Light ID) by holding a smart phone up to an LED light source equipped with high-speed and invisible flashing. After receiving the ID, the app will connect to a server to acquire the associated information, and show it on the screen.
Previous technologies allowing users to receive information with their smart phones have included image reading technology, such as QR Codes and AR Markers. However, they take a little time to focus on a printed pattern and to process a complicated image.
In contrast, Panasonic's Light ID technology does not require clear image of a source. Just by holding up a smart phone to an LED light source or an item reflecting that light source, the Light ID can be transmitted quickly. Even over short distances, when there are obstacles between light source and user, or even if a little hidden, Light ID technology works in any place which can be reached by the light. In a normal environment, Light ID's reading speed is within 0.3 seconds, and has made it possible to receive information transmissions in a comfortable way.
High-speed Reading with the Special Properties of Image Sensors
In order to read Light IDs at a high speed, the technology utilizes the special image-reading properties of the image sensor built-in smartphone cameras. Photography with a common image sensor can acquire an image in 1/30th of a second, but the new method developed by Panasonic has made it possible to detect the variations in brightness of an LED light source from within a single image. Data speeds of conventional visible light communication technology that utilizes image sensors, have been limited to ten-odd bps. But with this new technology, transmission of several kbps has become a possibility.
How Light ID is read at high speeds
Special Properties of Light ID, and its Superiority
To deal with radio-frequency interference and acoustic interference, information transmission methods utilizing Bluetooth or ultrasonic waves require a source to be located well away from the other sources - but there is no necessity as Light ID. Even when multiple Light ID-transmitting devices are located in immediate proximity to one another, users are able to switch between sources to receive information by slightly adjusting the direction of their smart phone.
A Technology Making Reverse O2O Possible
Light ID-transmitting devices can take the form of any LED light source: From indirect lightings for sign and show windows, to backlights of LCD used in digital signage. By high-speed and invisible flashing we can't see, it is possible to make it into a Light ID-transmitting light fixture or sign.
With Light ID, it is possible to provide detailed product information or coupons when a user holds up a smart phone to signage, posters, etc. It can be used even through indirect light, so it is also possible to receive information by holding up a smart phone to a product displayed in a show window. By using light, it is possible to link the real world to information on the internet, a technology which could also be called "reverse O2O (Offline to Online)."
Furthermore, this technology is expected to prove useful in providing information in the various native languages of users. Providing information for foreign visitors during the 2020 Japan Olympics and Paralympics is a topic of concern. This technology manages to show information translated into the language selected in the "language setting" of a user's smart phone simply by direct the smart phone to a sign.