  In this paper we reverse engineer the Sony IMX219PQ image sensor, otherwise
known as the Raspberry Pi Camera v2.0. We provide a visual reference for pixel
non-uniformity by analysing variations in transistor length, microlens optic
system and in the photodiode. We use these measurements to demonstrate
irregularities at the microscopic level and link this to the signal variation
measured as pixel non-uniformity used for unique identification of discrete
image sensors.
