| abstract |
The optical proximity detector (10) comprises a flexiblensubstrate (1) on which a plurality of light sources (6) andnphotodetectors (8) are arranged, consisting of thin, flexiblenlayers of organic semiconductors (3.1, 3.2) and transparentnelectrodes (2.1, 2.2, 4.1, 4.2). The light sources (6) emitncontinuous or pulsed light (7) through the transparentnelectrodes (2.1, 2.2, 4.1, 4.2). An object (9) close to thenlight-emitting surface of the detector (10) partiallynreflects this light (7), and a fraction of it reaches annadjacent photodetector (8) that converts this light into annelectrical signal. This signal contains information about thenproximity of the object (9), and the information can benextracted with an electronic circuit that is either measuringnthe amount of detected continuous light or demodulating thendetected light pulses. |