Cesium optical pump detector for buried and abandoned chemical weapons

A cesium optical pump detector for buried unexploded ordnance, comprising:

• a pumping light generation module configured to generate a near-infrared light;
• a first optical module configured to convert the near-infrared light into a circularly polarized light;
• a magnetic resonance module comprising:
• a radiofrequency coil configured to generate a radiofrequency electromagnetic field;
• and
• cesium absorption chamber comprising an elemental cesium, wherein based upon an interaction of the circularly polarized light, the radiofrequency electromagnetic field, and a magnetic field detected, the elemental cesium is caused to generate an opto-magnetic resonance to output a modulated near-infrared signal;
• a photoelectric detection module configured to receive the modulated near-infrared signal and convert the modulated near-infrared signal into an electrical signal;
• and
• a signal processing module electrically connected to the photoelectric detection module, comprising:
• an amplifying and filtering unit, a self-oscillation unit, a magnetic resonance frequency measuring unit, and a calculating unit which are sequentially and electrically connected, wherein
• the amplifying and filtering unit comprising:
• a first band-pass filter configured to coarsely measure a frequency of the electrical signal;
• and
• a second band-pass filter configured to finely measure the frequency of the electrical signal;
• the self-oscillation unit is further electrically connected to the radiofrequency coil to excite the radiofrequency coil, comprising:
• a first phase shifter electrically connected to the first band-pass filter;
• and
• a second phase shifter electrically connected to the second band-pass filter;
• the second band-pass filter comprises a plurality of first frequency band selection elements, the second phase shifter comprises a plurality of second frequency band selection elements respectively corresponding to the plurality of first frequency band selection elements, each of the plurality of first frequency band selection elements and each of the plurality of second frequency band selection elements corresponding to each other are configured to define one frequency band for finely measuring the frequency of the electrical signal;
• and
• the calculating unit is configured to calculated an intensity of the magnetic field detected based upon the frequency of the electrical signal;
• and
• a terminal control module electrically connected to the signal processing module, configured to acquire the frequency of the electrical signal coarsely acquired and select frequency bands for working of the second band-pass filter and the second phase shifter based upon the frequency of the electrical signal coarsely acquired when to finely measure the frequency of the electrical signal.