In order to control a device, you need to supply some form of input. That input can take many forms, from remote controls to keyboards to touch screens. In most cases, this means that you either have a corded device tied to a particular location, or you have a slew of portable wireless devices that you have to track down when you need them and be sure to keep the batteries charged. This is a problem that just begs for a simpler solution.
Seeking to provide that solution, a team from the Georgia Institute of Technology has developed OptoSense. OptoSense is a self-powered sensor that can detect ambient light levels. It has a thin and flexible form factor that can conform to the shape of the surface it is installed on. Being designed for large-area use and highly customizable applications, OptoSense has the potential to serve as a multi-purpose input controller ubiquitously deployed on everyday surfaces.
OptoSense consists of two primary components: a flexible sensing and energy harvesting surface, and a control circuit for computation and communication. The sensing surface can be implemented as a single sensor, or a one or two dimensional array of sensors, depending on the use case. The custom control circuit contains a microcontroller (Nordic nRF52832 with an Arm Cortex-M4 CPU) to interpret sensor input, and a Bluetooth Low Energy transceiver to communicate with devices such as phones and televisions.
With the various sensor configurations, the device can be used for many applications including multitouch pads, hover inputs, and gesture recognition. The sensors can also capture implicit inputs such as the detection of open/closed doors, presence detection, liquid sensing, and walking detection. Through the use of 3D-printed flexible optical masks, the sensor can adjust its detection range to fit a wide variety of tasks.
One drawback to the technology is that ambient light is required — it cannot function unless sufficient lighting is present. As such, you may not find OptoSense to be very useful if you need to turn your lights on. However, most human activities take place in a lighted environment, which leaves plenty of opportunity for this device to act as the universal, ubiquitous input device it promises to be.
Currently, the researchers are looking into the possibility of replacing their current silicon-based photodetectors with organic semiconductors. They have had some initial success and note that this could make the production of a thinner, more flexible, and less expensive device possible in the future.