Abstract
We investigated fluorescent nano diamonds as fluorescent markers for a direct electron-beam excitation
(D-EXA) optical microscope. The D-EXA microscope excites the nanometric region of the specimen in
an atmospheric pressure by electron beam irradiation. We used the fluorescent nano diamonds as
fluorescent makers because of their less photobleaching, low cytotoxity, high efficiency of emission.
They also can be excited both photoluminescence and cathodoluminescence, so it is possible to
demonstrate the correlative observations between the D-EXA microscope and a fluorescent confocal
laser microscope. We measured the cathodoluminescent spectra of fluorescent nano diamonds, and
presented that the D-EXA microscope can overcome the diffraction limit.
