Noise optimisation analysis of an active pixel sensor for low-noise real-time X-ray fluoroscopy

Theoretical calculations and simulation results for the noise of a hybrid active pixel sensor designed for real-time digital fluoroscopy are presented. Noise performance is given as a function of transistor dimensions, allowing the designer to choose appropriate device dimensions when designing flat-panel imaging circuits. Optimal device dimensions are derived for minimising the input referred noise of the active pixel to meet the stringent requirements for low-noise digital X-ray fluoroscopy (< 1000 noise electrons).