| Electron Multiplier |
Amplifies signals by utilizing
a sequence of dynodes that emit secondary electrons when struck by
an incident electron, creating a cascading effect. This results in
an amplified output current at the final anode, proportional to the
intensity of the initial signal. |
Very good signal amplification
to even one electron (may cause more noise dependent on gain), high
sensitivity, need high vacuum and high voltage, expensive. Limited
dynamic range, finite lifespan and need to be replaced periodically. |
| Faraday
Cup |
Charged particles,
such
as ions or electrons, enter the cup and transfer their charge to it,
causing a change in electric potential that can be measured over time
to infer the number of particles. |
Suitable for particles and
charge state detection. Simplicity and robustness, Wide dynamic range,
no need for high voltage and high vacuum. Lower sensitivity. Sensitive
to Secondary Emission directional sensitivity (direction of incoming
particles). |
| Microchannel Plate |
Similar to electron multiplier,
a two-dimensional matrix or “plate” of many tiny, parallel,
hollow channels made from a type of glass that can generate secondary
electron emissions upon incident particles striking the channel walls.
These secondary emissions create an electron avalanche down the channels
and amplifies the original signal. |
Signal Amplification (Not
as good as electron multiplier, but lower noise), Spatial Resolution
ability, shorter life expectancy due to channel aging and depletion
of the secondary emission material, smaller and cheaper than electron
multiplier. |
| Daly Detector |
Directing
ions onto a surface
(Doorknob) to trigger the emission of electrons, which are then accelerated
towards a phosphor screen to produce photons, that are subsequently
detected and amplified by a photomultiplier tube, thereby converting
the ion signal into a measurable electrical signal. |
High gain, ruggedness, wide
dynamic range, suitable for high mass and high energy ions. Limited
mass resolution, larger size and need high voltage, finite lifespan. |
