| 摘要 |
PURPOSE:To highly precisely heat a cathode, stably oscillate electron beams, and monitor the heating temperature of the cathode by controlling laser output with the radiated light from the heated surface of the cathode as a heating information source. CONSTITUTION:The laser beam 7 from a laser oscillator 6 radiates and heats a cathode 1 through an incident optical system 8, an optical fiber 9 and an emitting optical system 10. The cathode 1 is increased in temperature to emit thermions, and an accelerating voltage is added thereto to generate electron beams through a Wehnelt 3. The radiated light 11 from the cathode heated surface is entered to a monitor fiber 12 through the emitting optical system 10, reversely sent, and branched by a branching part, and only a necessary wavelength is taken out by a cut filter 17 on the emitting end surface. The signal obtained by a temperature measuring instrument 13 is then sent to a temperature controller 14 to monitor, and stable heating and also stable output of electron beams are conducted by a laser controller 15. |
