Dissector tube

Image dissector tube. Figure 2 shows a schematic representation of an image dissector tube. The active surface of the image dissector tube is an S-20 photocathode (2 ) similar to that... 

Image dissector tubes (Fig. 26) make use of an entrance aperture behind the photocathode, by which the photoelectrons stemming from different locations of the photocathode can be scanned and measured after amplification in the dynode train, as in a conventional photomultiplier. Although used in combination with an echelle spectrometer with crossed dispersion for flexible rapid sequential analyses [59], these systems have not had any commercial breakthrough. This might be due to the limited cathode dimensions but also to stability problems. 

Fig. 26. Image dissector tube, (a) Photocathode, (b) accelerating electrode (mesh), (c) deflection coils, (d) aperture, (e) electron multiplier.

Dissector tube [45] up to 60 mm " 200-800 similar linear dynamic range >10"... 

The photo-multiplier tube (PMT) as a one-channel detector could not be an alternative. Even though the PMT is an almost perfect photon detector, offering shot-noise limited measurements for almost every photon flux, but its resfliction to exclusive sequential registration of spectral intervals makes it, and also the different types of dissector tubes, unsuitable for application in CS AAS. 

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