A touchless user interface based on a near-infrared-sensitive transparent optical imager

Touchless user interfaces that are based on gestures typically rely on near-infrared cameras. However, such systems are often hampered by their limited field of view and high-accuracy calibration requirements. Here we report a touchless user interface that is based on a visually transparent near-infrared-sensitive organic photodetector array and can be used on top of a display. Optical transparency is achieved by using a printed copper grid as a bottom transparent conductive electrode and an array of patterned organic photodetector subpixels. Electro-optical modelling is used to optimize the design of the image sensor, leading to a photodetectivity of approximately 10^12 Jones at 850 nm and a high visible-light transmittance of 70%. We show that the imager can be used as a penlight-controlled and gesture-controlled touchless user interface when combined with a commercial display.

Takeshi Kamijo, Albert J. J. M. van Breemen, Xiao Ma, Santhosh Shanmugam, Thijs Bel, Gerard de Haas, Bart Peeters, Razvan Petre, Daniel Tordera, Roy Verbeek, Hylke B. Akkerman, Luis Moreno Hagelsieb, Florian de Roose, Itai Lieberman, Fujito Yamaguchi, René A. J. Janssen, Eric A. Meulenkamp, Auke Jisk Kronemeijer, Gerwin H. Gelinck