The published and other information about input ion optics of quadrupole mass spectrometer with inductively coupled plasma are integrated and systematized in this review. This part of review is devoted to asymmetrical optical systems with deflectors for parallel shift of the ion beam. There were revealed the reasons for choosing this optics based on its benefits. All variants of such optics were divided into two chronological groups - before and after their combination with multipole reaction-collision cells. The features of design and functioning of different types of cells and deflectors were discussed. The behavior of extracted plasma particles inside of different parts of optics were also considered. In particular, initial explanation of the positive effect in the soft mode extraction of ions introduced into the optics came under doubts and criticism, so alternative theory was offered instead. Main attention was paid to the сonstruction, positioning and properties of two the above-mentioned chronological groups of optical systems of different mass spectrometers: first (1983-2000 years), used in PMS 100/200/2000, HP 4500, Agilent 7500a/i/s, ICPM 8500, EMS 200 and TS Sola; and second (1999-2014 years), equipped with hexapole cells in Platform ICP/XS, PQExCell, XSeriesI/II, ICP-MS2000, or with octapole cells in model series of Agilent 7500c/cs/ce/cx/7700/8800/7900. There was considered conceptual novelty of triplemultipole mass spectrometer Agilent 8800 ICP-QQQ, which makes possible its outstanding efficiency in the elimination of spectral overlap, improvement the reliability of analytical results and lowering detection limits, confirmed by numerous authors when analyzing the set of difficult samples with complex composition.