Patent ID: 8314381

Claim:
Reflector for a time-of-flight mass spectrometer for reflecting ionized atoms and/or molecules, said reflector having an entry opening ( 25 ) and an arrangement of successively arranged ring electrodes ( 31 , 29 ) extending away from the entry opening ( 25 ) along a longitudinal axis ( 21 ) of the reflector ( 9 ), wherein the ring electrode ( 31 ) closest to the entry opening ( 25 ) is at an opposite electric potential compared to the other ring electrodes ( 29 ), wherein a screening electrode ( 41 ) is provided on a side of the entry opening ( 25 ) facing away from the ring electrodes ( 31 , 29 ) and wherein the screening electrode ( 41 ) lies at a potential that differs from that of the ring electrodes ( 31 , 29 ).