They allow you to see through cloaking devices.
The reason there are different types is because either Aaron planned to add different scanners that were effective against certain types of Cloaking or just options for modders.
I think a couple of mods employ that One type of scanner is more effective than others depending on what type of cloaking they use. Either way, in Stock SEIV scanners do the same as each other, you only need one type from Hyper-Optics, Tachyon, Gravtic, Temporal or Psychic to see through claoking devices of an equal level
Re: Scanners - WTF?
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