In many cases the time for optical system design can be considerably reduced if the possibility exists of adoption of the real optical system with acceptable aberration properties and characteristics close to the desired ones (the so-called prototype). In order to use such a possibility a certain work has been fulfilled for realizing the data base with ready optical systems, the results of the work being reported here at our conference in another paper. But the prototype adoption requires us to carry out profound analysis of aberration properties of the possible prototypes and to select the most acceptable one. The use of classical approaches of aberration analysis doesn't permit us to investigate thoroughly the interconnection between the aberration properties and the ones of the lens forms. The questions are: how to reveal the potential possibilities of the lens forms? How to find the most optimal fields of use of the real optical systems and how to select such a lens form that can provide the best imaging? In connection with the foregoing we developed a principally new approach for investigations of the aberration analysis and limiting possibilities of optical systems. This approach is based on investigation of behavior of the aberration functionals depending on the special method of variation of an angular field of view and an aperture.