Power Efficiency Figure of Merit for Image Sensors

A new figure of merit (FoM) is developed with a theory, which enables the comparison of power efficiency of different image sensors based only on the pixel array size, frame rate, and total power consumption. The mathematical foundation of the FoM is provided, enabling the application of FoM to a generic image sensor supporting various read-out configurations. The model assumes a nonlinear relationship between the power consumption and operating frequency of building blocks, and the nonlinear factor is numerically derived based on the analytical modeling of image sensors. The FoM is applied to the studies from 1999 to 2018, which clarifies the trend of improvement as well as visualizes several breakthroughs in the development history.