We tested our 2-D Detector's in "negative charged particle mode".
This is a spectra.
As you seen, this resolution was worse than "positive mode" (for example this).
In this situation, the count rates was higher, a factor of 3, than before.
And another problem exists.
The signel from MCP-front has had ringing noise.
In the following image, the yellow line is it.
This image was taken when MCP-back signal was grounded.
This image was taken by MCP-back signal was bypassed through Amplifer.