plural of that noun unless something else is specifically stated furthermore the terms first second third and the like in the description and in the claims are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order it is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein moreover the terms top bottom over under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions it is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other orientations than described or illustrated herein in the context of the invention target can be any interior region including lung bladder abdominal cavity knee joint and the like the examining physician could examine the interior region and upon noticing a suspicious region i e a lesion he can view in situ the single cells of the lesion in the same context macroscopic view refers to viewing a larger area of the target and microscopic viewing refers to viewing the target at a cellular level with high sensitivity fig1 shows an objective lens system 100 with an optical axis 150 according to the invention it consists of one lens as shown in this example the lens 100 has a first part 120 with an aperture radius r 1 and a second part 110 with an aperture radius r 2.