Life beyond 1MeV – like life after 40 – is not too different unless one
takes advantage of past experience and is receptive to new opportunities. At
first glance, the returns on performing electron microscopy at voltages
greater than 1MeV diminish rather rapidly as the curves which describe the
well-known advantages of HVEM often tend towards saturation. However, in a
country with a significant HVEM capability, a good case can be made for
investing in instruments with a range of maximum accelerating voltages. In
this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will
complement the other 650KeV, 1MeV, and 1.2MeV instruments currently
operating in the U.S. One other consideration suggests that 1.5MeV is an
optimum voltage machine – Its additional advantages may be purchased for not
much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which
seem to be operated at 2MeV maximum, are much more expensive.