Discrete dynode detector with dynamic gain control

摘要

A novel electron multiplier that regulates in real time the gain of downstream dynodes as the instrument receives input signals is introduced. In particular, the methods, electron multiplier structures, and coupled control circuits of the present invention enable a resultant on the fly control signal to be generated upon receiving a predetermined threshold detection signal so as to enable the voltage regulation of one or more downstream dynodes near the output of the device. Accordingly, such a novel design, as presented herein, prevents the dynodes near the output of the instrument from being exposed to deleterious current pulses that can accelerate the aging process of the dynode structures that are essential to the device.

主权项

1. A method for operating a particle detector comprising:
(a) receiving incident particles that represent at least one input signal in the particle detector; (b) emitting electrons from a first dynode in response to receiving the incident particles; (c) directing the emitted electrons to a plurality of additional dynodes arranged in a cascading relationship; (d) measuring a partitioned detection current generated at an intermediate dynode wherein electrons striking a part of the total surface emitting area provide the partitioned detection current and wherein electrons striking a remaining surface emitting area are allowed to propagate in a normal mode; and, (e) adjusting a voltage applied to at least one dynode positioned downstream of the intermediate dynode in real time based on the measured partitioned detection current.