FUNPET - half ion funnel, half ion carpet

FUNPET is a hybrid ion funnel ion carpet MS interface. It combines the advantages on an classical stacked ring RF-only driven ion funnel and an ion carpet.
The ion carpet consists of multiple planar (isolated) metal rings with decreasing diameter stacked together. In the center there is orifice.

To each of the rings there is an RF and  DC applied. The RF (180 degrees out of phase between the rings) keeps the ions away from colliding with the rings and confines them in front of the ion carpet and its centric orifice. The DC is decreasing the closer it gets to get orifice, providing a electric gradient field for focusing the ions into the orifice and transmitting them into the next pressure stage.

Interestingly, the design includes an jet disruptor which causes dissipation of neutral gas molecules and therefore reduces the gas load for the next vacuum stage and increases ion transmission.

More information about the FUNPET and the ion carpet technology can be found at

https://link.springer.com/article/10.1007%2Fs13361-018-2038-3

or under http://www.massspecpro.com/technology/ion-optics/ion-carpet