Massenspektrographen mit doppelfokussierung erster ordnung für alle massen, die geringe bildfehler in einem grossen massenbereich entlang der photoplatte aufweisen

The properties of the aberration coefficients of the mass spectrographs with first order double focusing along a straight image line are examined, of which in a previous paper⁶) was shown that in one point of the image line two or three of the aberration coefficients are zero. It results that for some of these instruments, besides the mentioned advantages, further improvements are possible. There exist not only instruments in which some aberration coefficients vanish in additional points at the photographic plate, but also instruments with small aberration coefficients in a wide range of the plate. The dimensions of especially favourable mass spectrographs are given in a table, the progress of the aberration coefficients belonging to them is shown in diagrams and the positions of the zero points of the coefficients are indicated in a table.