TL;DR
Boris Homiakov has created an ultra-simple digital camera that uses a single photoresistor as its image sensor. This camera captures images one pixel at a time by moving the photoresistor along two axes, effectively functioning like a primitive scanner. Instead of the complex sensor arrays found in modern cameras, Homiakov's design relies on the photoresistor's ability to vary resistance based on light exposure, recording brightness at each point to build a complete image.