熱陰極フイリップス型電離真空計に就て

抄録

By adding a thermal electron emitter to the ordinary cold cathode Philips gauge, a high sensitive ionization gauge is expected which works with the linear characteristics at normal operating voltage where usual ion gauges are operated, An additive fine needle extended at the cylindrical axis of the hot-cathode philips type ion gauge to collect the ion current, enables one to extend its measurable range to the ultra-high-vacuum region, in accordance to the principle of Bayard-Alpert ionization gauge with greater ease, Under these considerations, we have prepared several gauge tubes and have measured their characteristics.
With such Philips-Alpert type ion gauge, the experimental results were satisfactory. The sensitivity was about 5 microamperes for the pressure p=1×10^-6 mmHg under the working condition of 600 volts to the anode, -200 volts to the repeller and the needle at a magnetic flux density of about 200 gauss. At this time the electron c current Ie was about 1 mA. The linearity was confirmed over the pressure range from 2×10^-6 to 1×10^-4mmHg, and a good stability was found.
The simpler hot-cathode Philips type ion gauge showed also a large sensitivity, but its characteristics was meager in its linearity and stability.