本文介绍的是一种简单、紧凑和可靠的液氮液面监测器。此种监测器用细铜丝连续监测杜瓦容器内的液氮液面。监测器有一只相似计和作为指示器的高发射二极管,液面分辨率好于±10mm。介绍了传感器结构和传感电路。监测器装有一套液氮自动重新充填系统和供给探测器高偏压的远距离断路,还装有一台警报器。当液氮液面过低或供液用完时,就会发出声响。 This article describes a simple, compact and reliable liquid nitrogen level monitor. This monitor continuously monitors the liquid nitrogen level in the Dewar vessel with thin copper wire. Monitor has a similar meter and as a high-emitting diode indicator, the liquid level resolution better than ± 10mm. The sensor structure and sensing circuit are introduced. The monitor is equipped with an automatic nitrogen liquid nitrogen refill system and remote disconnection to the detector at high bias and is equipped with an alarm. When the liquid nitrogen level is too low or the liquid runs out, it will make a sound.