Pixel having a photoemitter and a photodetector triggered by a pixel selector signal bus

An electronic device comprising:

• a cover glass of a display having a display surface;
• a pixel selector signal bus configured to communicate a pixel selection signal component;
• a pixel array of the display, the pixel array being electrically connected to the pixel selector signal bus and including multiple pixels configured to sense an image of an object in contact with a surface of the display, each pixel in the pixel array including one or more photodetecting elements and one or more photoemitting elements, operation of each pixel being switched between the one or more photodetecting elements and the one or more photoemitting elements by the pixel selector signal component received from the pixel selector signal bus;
• and
• image processing circuitry electrically coupled to the pixel array and configured to scan light from multiple pixels of the pixel array and stitch a light signal reflected from a refractive boundary at the display surface and received by photodetecting elements of the pixelated photodetecting element array into a composite image of the object.