| 摘要 |
<p>PURPOSE:To eliminate irregularities in the emitting intensity of light of a fluorescent recording head in a longitudinal direction by changing a space between a cathode filament and a grid electrode in accordance with the position of a fluorescent material in an extended direction. CONSTITUTION:A motion equation of electrons released by a cathode filament is F=qE, if a grid electrode 5 and a cathode filament 6 are arranged in parallel. Then formula I is established due to the relationship of E=-qrdV, F=m, E=V/D (but q is the amount of charged electrons, m is the mass of an electron, alphais acceleration, D is a distance between the grid electrode 5 and the cathode filament 6, and V is a potential difference between the grid electrode 5 and the cathode filament 6). Thus the acceleration of the electron is allowed to change due to not only the potential difference V between the grid electrode 5 and the cathode filament 6 but also a distance D between the grid electrode 5 and the cathode filament 6 according to formula I. That is, if the distance D is set in accordance with a potential gradient generated in the cathode filament 6, the acceleration alpha of the electron can be made constant.</p> |
