Which type of waves are used in electron microscope ?

Explanation

To measure very small distance (like size of molecule) `(10^(-8) m "to" 10^(-10) m)` vernier callipers or screw gauge can not be used. Optical microscope uses visible light. Wavelength of visible light is of the order of `4000Å` to `7000Å(1Å=10^(-10)m)`
Light has wave nature. Hence to measure (resolve) length equal to size of visible light optical microscope can be used.
But it can not be used to measure (resolve) dimension less than `10^(-10)` m.