Determination of Paraxial Image Plane location by using Ronchi test

A method to determine the location of the Paraxial Image Plane of an imaging system is discussed. This method uses a recently developed quantitative Ronchi test and is different in that the location of Paraxial Image Plane of the system can be determined from the measured Ronchigrams alone. We validate the location determined by the method by modifying the optical setup and comparing the retrieved f-number of the system to the theoretical prediction.