One-dimensional sensor modulation transfer function, revisited

Abstract

In this theoretical study the modulation transfer function (MTF) of an ideal one-dimensional image sensor array is calculated using computer simulations and simple mathematical concepts. These calculations take into account the finite size of the pixels, the discrete and periodic arrangement of the pixels, and the effect of the phase shift between the pixel array and the signal incident on the imager. It is found that the actual MTF of the sensor is more feature rich than implied by the Sinc function. In particular, when imaging periodic patterns on the sensor, for example to measure the resolution, phase shift between the incident pattern and the sensor and the spatial frequency can dramatically affect the results. An exact formula for the phase averaged MTF is derived.