Rectilinear ion trap（RIT） has the advantages of simple structure

strong trapping capacity

and large storage capacity

and has been widely used.In order to further improve analysis ability of RIT

ion trapping ability of RIT in the third stable zone is researched

and analyze on the influence of the initial kinetic energy of the ion under different end cap voltages on the RIT trapping ability

and the lower trapping ability shown by it is analyzed.According to the analysis

ions from the outside of the ion trap pass through the through hole of the end cover electrode of the ion trap entrance under the effect of initial kinetic energy

and are affected by the end cover electrode and the x and y electrodes when entering the trap

causing ion loss.The traditional RIT geometry structure is optimized to reduce the impact of the uneven electric field on flying ions under the same initial kinetic energy

thereby reducing ion consumption.The research results show that when the end cap electrode voltage EC is 60 V and the initial ion kinetic energy is 6 eV

the RIT capture efficiency can reach 89 %

which not only retains the advantages of the simple structure of the RIT

but also achieves a higher capture capacity.