PURPOSE: To provide an electron beam device, which can converge beam diameter to submicron or less on a target surface, and of which structure is simplified to reduce a cost, and of which weight can be reduced, and of which space volume is small, especially of which height is low, and in which the number of rack for housing control equipment and power source equipment is small, and in which adjustment part is few to simplify the adjustment for outputting the device performance, and in which the number of parts is small, and which has the high reliability.

CONSTITUTION: In an electron beam device for irradiating electron beam 203 from an electron source 201 to a target 204, One electrode 202 is located between the electron source 201 for discharging electron beams in parallel with each other or in parallel practically and the target 204, and a power source 207 for giving the desired potential to the electrode 202 is provided. The electron beam 203 is accelerated by the electrode 202, and while is converged finally to arrive the target 204.