Here is the diagram of my Arduino infrared close proximity sensor. As you can see, ... (TP4), which is logic-low (L) by default, shifts to a logic-high (H) state for a while when an object appears ...

In-sensor image memorization and encoding via optical neurons for bio-stimulus domain reduction toward visual cognitive processing. Nature Communications , 2022; 13 (1) DOI: 10.1038/s41467-022-32790-3 ...