Ultrasensitive Flexible Proximity Sensor Based on Organic Crystal for Location Detection

A new type of flexible proximity sensor that uses a microsized organic crystal as the sensing element is demonstrated. The two-terminal organic sensor can accurately perceive the external objects, such as the human finger, fiber, and even atomic force microscopy tip. The proximity sensor shows an unprecedented distance resolution of 0.05 mm, which is 2 orders of magnitude higher than that of the previously reported conventional capacitor proximity sensors. A novel method has been proposed to realize the location detection of the approaching unknown-charge object by changing the distance between the stimulus and the sensor. Our results open a new route to realize an ultrasensitive perception of objects, making it a promising candidate for applications in artificial intelligence, healthcare systems, and high-precision robots.