Using a rotating test pattern for MTF measurement of staring array sensors

摘要

This paper describes the use of a rotating test pattern or reticle to measure the Modulation Transfer Function (MTF) of a staring array sensor. The method finds the Edge Spread Function (ESF) from which the MTF can be calculated. The rotating reticle method of finding the ESF of a sensor has several advantages over the static tilted edge method. The need for precise edge alignment is removed. Motion blur is used to simultaneously average out the effect of undersampling and to oversample the edge. The improved oversampling allows reduction of the noise in the generated ESF while keeping a high resolution. A unique data readout technique reads edge data perpendicular to the edge. Perpendicular readout eliminates the need to know or estimate the slope of the tilted edge. This MTF measurement method is validated using simulation and actual data captured by a digital camera. The resulting ESF plots agree well with expected results.