負グローの周波数依存性についての研究

Abstract

The performance of a Ne-Hg negative glow lamp (having no positive column) was measured at different frequencies. The results showed that the efficiency decreased as frequency increased. The plasma characteristics were measured by a Langmuir probe and spectroscope to analyze this phenomenon. The following results were observed:1. There were two groups of electrons, first electrons and second electrons, in this plasma, and there was a period without first electrons at high frequency.2. The energy of the second electrons at high frequency operation is lower than at low frequency.3. Peak energy of the first electrons at high frequency operation is higher than at low frequency.From these results we attribute the reason the efficiency of this lamp becomes lower at high frequency to the following.(1) The energy of the second electrons at high frequency operation is lower than at low frequency because the second electrons, which can get the energy only from electron-electron collision, but cannot get energy in the period without first electrons.(2) Ionization loss at high frequency operation is higher than at low frequency because the peak energy of the first electrons at high frequency operation is higher than at low frequency.Lastly the performance of negative glow, in a Ne-Hg lamp and Ar-Hg lamp with a positive column, was checked by observing the spectrum. The measurement results shows that there was no discrepancy to the conclusion that the peak value of cathode fall voltage at high frequency operation is higher than at low frequency.It has been reported that the cathode fall voltage at high frequency operation is lower than at low frequency. In this paper we found out that the m.r.s. of cathode fall voltage at high frequency operation was lower than at low frequency, but that the peak value of cathode fall voltage at high frequency was higher than at low frequency.