CN206400119U - A kind of new caesium optical pumping magnetic spy instrument probe device - Google Patents
A kind of new caesium optical pumping magnetic spy instrument probe device Download PDFInfo
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- CN206400119U CN206400119U CN201621423193.2U CN201621423193U CN206400119U CN 206400119 U CN206400119 U CN 206400119U CN 201621423193 U CN201621423193 U CN 201621423193U CN 206400119 U CN206400119 U CN 206400119U
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Abstract
The utility model discloses a kind of new caesium optical pumping magnetic spy instrument probe device, mainly include radio frequency induction device, heater, caesium lamp, Fresnel Lenses, split beam formula polarizer, Cs atom absorption chamber, heating coil, sleeve, thermistor, lens, optical filter, photodiode and shell；In the presence of heater and radio frequency induction device, caesium Metal gasification in caesium lamp, Cs atom is luminous by high frequency pumping, produce the pump light of 894.3nm service bands, pump light is by beam-expanding collimation after Fresnel Lenses into directional light, directional light changes into left and right rotatory polarization light by split beam formula polarizer, and polarised light produces optical pumping effect inside Cs atom absorption chamber；Cs atom absorption chamber is heated by heating coil, while thermistor feeds back lamp house temperature, keeps the heating-up temperature of Cs atom absorption chamber stable；Lens, optical filter converge at useful optical signal on photodiode, and photodiode converts optical signals into electric signal.
Description
Technical field
The utility model is related to Weak magentic-field detection, magnetic prospecting, the spy of magnetic anomaly detection equipment caesium optical pumping magnetic spy instrument
Head designing technique, mainly a kind of new caesium optical pumping magnetic spy instrument probe device.
Background technology
Under the long term in magnetic field of the earth, paramagnetic material retains stronger magnetic.When not being produced, paramagnetic material is buried
In the earth, enormous amount can show as being different from architectonic mutation magnetic field around.After man-made recovery, its magnetic characteristic is normal
It is used as a kind of detection means.A large amount of magnetics such as non-explosive UXO, submarine, because there is the change for causing earth's magnetic field around in it,
And magnetic is detected and positioned as magnetic spy instrument.Optical pumping magnetic spy instrument is high because of its sensitivity, as various countries' research object.
Caesium optical pumping magnetic spy instrument is based on Cs atom energy level produces Zeemen effect in magnetic field, in optical action and caesium original
Son is absorbed in the presence of outdoor application radiofrequency field, and Cs atom produces magnetic resonance in Atomic absorption room.Now the frequency f of radiofrequency field is
For Larmor frequency, itself and external magnetic field H0It is directly proportional.
F=γ H0
Wherein γ is gyromagnetic ratio, γ ≈ 3.5Hz/nT.
Utility model content
The purpose of this utility model is to overcome the shortcomings of that prior art is present, and provides a kind of new caesium optical pumping magnetic spy instrument
Probe apparatus.
The purpose of this utility model is completed by following technical solution.This new caesium optical pumping magnetic spy instrument probe dress
Put, mainly including radio frequency induction device, heater, caesium lamp, Fresnel Lenses, split beam formula polarizer, Cs atom absorption chamber, plus
Heat coil, sleeve, thermistor, lens, optical filter, photodiode and shell；In the effect of heater and radio frequency induction device
Under, the caesium Metal gasification in caesium lamp, Cs atom is luminous by high frequency pumping, produces the pump light of 894.3nm service bands, pump light
By beam-expanding collimation after Fresnel Lenses into directional light, directional light changes into left and right rotatory polarization by split beam formula polarizer
Light, polarised light produces optical pumping effect inside Cs atom absorption chamber；Cs atom absorption chamber is heated by heating coil, while hot
Quick resistance feedback lamp house temperature, keeps the heating-up temperature of Cs atom absorption chamber stable；Lens, optical filter converge useful optical signal
In on photodiode, photodiode converts optical signals into electric signal；Larmor frequency passes through after amplifying through multipole signal
Phase shifter formation self-oscillation loop in signal processor, while being counted to Larmor frequency, reads corresponding frequency values, turns
Change the magnetic field of the earth for being presently in position into；When former in the RF field frequency produced by the coil on sleeve and Cs atom absorption chamber
When the Larmor frequency of sub- magnetic resonance is consistent, it can be formed after the phase shifter phase shift in caesium optical pumping magnetic spy instrument in signal processor
Self-excitation is tracked.
Further, thermostatic control is carried out to Cs atom absorption chamber by the temperature control circuit in magnetic spy instrument.
Further, the work spectral line produced by caesium lamp is expanded into by Fresnel Lenses and worked with Cs atom absorption chamber
The big directional light such as face.
Further, Cs atom absorption chamber fills buffer gas, and the relaxation effect for reducing atom in atomic air chamber improves magnetic spy
The sensitivity of instrument；And the OTS films for adapting to hot operation are plated in Cs atom absorption chamber, narrow Atomic absorption room line width and improve sensitive
Degree.
Further, caesium lamp is column, and bottom heater gasifies to the metal in its caesium lamp, while using radio frequency sense
Mode is answered to encourage caesium lamp.
The beneficial effects of the utility model are：With eliminating, steering is poor and narrower.It need not be watched using numerous and diverse complicated orientation
Dress system scheme, simple detector is that global any dipping magnetic inclination angle region can be achieved quickly to carry out the work.The more conventional magnetic anomaly of the present invention
Detector has higher magnetic resonance signal and relatively low optical noise, can realize high-precision magnetic anomaly detection ability.The present invention
Using new-type pumping lamp, the life-span of raising magnetic anomaly detector that can be larger.This feature is beneficial to improve military antisubmarine helium light
The ambient adaptability and reliability of pump magnetic spy instrument, can be visited with the magnetic anomaly of the quick and convenient observation for realizing earth magnetism and military target
Survey, Rapid Implementation can be realized for geological and mineral exploration and military magnetic anomaly detection target.
Brief description of the drawings
The new caesium optical pumping magnetic spy instrument probe apparatus structures of Fig. 1；
Fig. 2 split beam formula polarizer constructions schematic diagrames；
Fig. 3 plates OTS films, fills buffer gas absorption cell structure；
Fig. 4 plating Parafilms absorb cell structure 1；
Fig. 5 plating Parafilms absorb cell structure 2.
Description of symbols：Radio frequency induction device 1, heater 2, caesium lamp 3, Fresnel Lenses 4, split beam formula polarizer 5, caesium is former
Sub- absorption chamber 6, heating coil 7, sleeve 8, thermistor 9, lens 10, optical filter 11, photodiode 12, shell 13.
Embodiment
Detailed introduction is done to the utility model below in conjunction with accompanying drawing：
As illustrated, this new caesium optical pumping magnetic spy instrument probe device, mainly includes radio frequency induction device 1, heater 2, caesium
Lamp 3, Fresnel Lenses 4, split beam formula polarizer 5, Cs atom absorption chamber 6, heating coil 7, sleeve 8, thermistor 9, thoroughly
Mirror 10, optical filter 11, photodiode 12 and shell 13；In the presence of heater 2 and radio frequency induction device 1, the caesium in caesium lamp 3
Metal gasification, Cs atom is luminous by high frequency pumping, produces the pump light of 894.3nm service bands, and pump light is saturating by Fresnel
Beam-expanding collimation is into directional light after mirror 4, and directional light changes into left and right rotatory polarization light by split beam formula polarizer 5, and polarised light exists
The inside of Cs atom absorption chamber 6 produces optical pumping effect, and (solid-state is presented in Cs atom at normal temperatures, when only realizing gasification, and Cs atom is
The atomicity of abundance is can guarantee that, optical pumping effect and electromagnetic induction phenomenon are produced with pump light).Cs atom is inhaled by heating coil 7
Receive room 6 to heat, while thermistor 9 feeds back lamp house temperature, keep the heating-up temperature of Cs atom absorption chamber 6 is stable (to be loaded on and contain line
Atomic absorption room in snare cylinder is under heating coil effect, caesium Metal gasification in Atomic absorption room.Ensured by thermistor
The temperature of Atomic absorption formula is constant, and now incident light produces optical action to the gasification state Cs atom in Atomic absorption room)；Lens
10th, optical filter 11 converges at useful optical signal on photodiode 12, and photodiode 12 converts optical signals into electric signal；
Larmor frequency forms self-oscillation loop after amplifying through multipole signal by the phase shifter in signal processor, while to Rameau
That frequency counting, reads corresponding frequency values, is converted into being presently in the magnetic field of the earth of position；When the coil on sleeve 8 is produced
When raw RF field frequency is consistent with the Larmor frequency of nuclear magnetic resonance in Cs atom absorption chamber 6, by caesium optical pumping magnetic spy instrument
Self-excitation tracking can be formed after phase shifter phase shift in middle signal processor.
Thermostatic control is carried out to Cs atom absorption chamber 6 by the temperature control circuit in magnetic spy instrument, it is higher in operating ambient temperature
When, the temperature heat time of Cs atom absorption chamber is shorter, when the temperature of the surroundings is low, during the gasification heating of Cs atom absorption chamber 6
Between it is longer.Design Fresnel lens and beam-expanding collimation is carried out to non-ideal spot light, by Fresnel Lenses 4 by produced by caesium lamp 3
Work spectral line expand into and the big directional light such as the working face of Cs atom absorption chamber 6.Cs atom absorption chamber 6 fills buffer gas, subtracts
The relaxation effect of atom improves the sensitivity of magnetic spy instrument in few atomic air chamber；To realize Cs atom absorption chamber size reduction, improve
Atomic absorption room density, the OTS films for adapting to hot operation are plated in Cs atom absorption chamber, are narrowed Atomic absorption room line width and are improved sensitive
Degree.Its structure is as shown in Figure 3.Caesium lamp 3 is column, and bottom heater gasifies to the metal in its caesium lamp 3, while using penetrating
Frequency induction mode excitation caesium lamp 3.
Polarized atom number is improved by photoinduction atom desorption (LIAD) method and plated film mode, avoids caesium former
The Henan of Cs atom reduces Cs atom absorption chamber sensitivity decrease in advance in sub- absorption chamber.Design special Atomic absorption cell structure and stone
Wax plated film Cs atom absorption chamber, narrows Atomic absorption room line width and improves sensitivity, it has three kinds of peculiar structure charts 4, Fig. 5 institutes
Show.
Caesium lamp is the pumping source in caesium optical pumping magnetic spy instrument, and it produces 894.3nm pump lights.This new middle Fresnel Lenses by
Lucite is made, and its material has the advantages that thin, light, and its light transmittance is not less than optical glass convex lens.Batch production, system
Make cost relatively low, it is cost-effective.It for non-ideal spot light as caesium lamp there is good beam-expanding collimation to act on.Divide ripple
Beam formula polarizer is made up of left-handed and dextropolarization piece, and this kind of polarizer can effectively reduce turning in caesium optical pumping magnetic spy instrument probe
To difference, the sensitivity of caesium optical pumping magnetic spy instrument is improved.Design left-right rotary polarised light and eliminate the method for turning to difference, pass through split beam formula
The mode of Cs atom in polarizer generation different polarization optical pumping Cs atom absorption chamber, which overcomes caesium optical pumping to pop one's head in, itself to be had
Steering it is poor.
Cs atom absorption chamber is the key componentses for occurring electromagnetic induction phenomenon.Itself and caesium lamp behaviour quality decide caesium optical pumping
The performance of magnetic spy instrument.In the normal work of caesium optical pumping magnetic spy instrument probe, to ensure that enough Cs atom numbers participate in optical action
Under magnetic resonance, caesium absorption chamber needed by winding heating coil to realize that the caesium metal evaporation inside Cs atom absorption chamber reaches
Suitable Cs atom number.In caesium optical pumping magnetic spy instrument, the heating-up temperature of caesium absorption chamber needs accurate stability contorting, 0.1 degree Celsius
Temperature fluctuation can cause the special magnetic fluctuation of several skins.It is the heating and temperature control for realizing Cs atom absorption chamber during this is new,
Heat sensitive electronic is provided with Cs atom absorption chamber tube wall and is accurately controlled absorbing room temperature.
This new design plated film Cs atom absorption chamber, improves Cs atom polarization number.In Cs atom absorption chamber, Cs atom with
Relaxation problem between glass absorption chamber, can cause the Cs atom of absorption chamber to polarize number reduction to reduce the sensitive of caesium optical pumping magnetic spy instrument
Degree.This new design realizes the longer Cs atom relaxation time using paraffin coating technique, OTS coating techniques, has reached several
Hz magnetic resonance line width.
It is the optical pumping magnetic spy instrument of auto-excitation type that this is new.The radiofrequency field produced when the coil of sleeve inside Cs atom absorption chamber
Frequency with external magnetic field when the Larmor frequency that Cs atom energy level transition is produced is consistent, in the presence of phase shifter, caesium light
Pump magnetic spy instrument optical pumping probe produces self-excitation phenomena.Electromagnetic induction phenomenon, the Larmor frequency of atomic transition occur for Cs atom absorption chamber
Signal comes together in photodiode by lens focus.To avoid the spuious optical noise of caesium light from entering photodiode.This is new
It is designed with narrow-band pass filter and noise reduction process is carried out to it.Photodiode changes into the Larmor frequency in electromagnetic induction phenomenon
Electric signal.In optical pumping probe, magnetic resonance only is produced when the frequency that sleeve coil is produced is consistent with Larmor frequency, but not
Self-excitation can be formed.It need to dock and reel the phase shift of More's frequency signal and could realize self-excitation.Now, by being carried out to the Larmor frequency
Count, the magnetic field value of caesium optical pumping magnetic spy instrument present position can be just derived by the relational expression of Larmor frequency and external magnetic field.
Each component that optical pumping is popped one's head in the utility model caesium optical pumping magnetic spy instrument is installed in cylinder-like shell 14, and optical pumping is visited
Each transmission cable is connected composition caesium optical pumping magnetic spy instrument with backend electronics components by special purpose interface.
The utility model caesium optical pumping magnetic spy instrument uses auto-excitation type magnetic spy instrument.Only when radiofrequency field and Larmor frequency one
Cause, when forming self-oscillation by phase shifter phase shift, the tracking of external magnetic field could be formed.By being carried out to Larmor frequency f
Count, external magnetic field value H can be measured0。
In caesium optical pumping magnetic spy instrument, the energy level of Cs atom division is more, so that caesium resonance line is more.Wherein Cs atom is total to
Shake relatively near between spectral line, when the optical axis that optical pumping is popped one's head in changes with external magnetic field angle, caesium optical pumping magnetic spy instrument optical pumping pops one's head in go out
Turn now to difference.When the platform for being mounted with caesium optical pumping magnetic spy instrument probe occurs because of motor-driven to be turned to, optical pumping probe will be due to
There is the situation of magnetic detection false-alarm wrong report in the intrinsic difference problem that itself turns to.
Understand that the sensitivity δ B of optical pumping magnetic spy instrument are according to atomic theory analysis：
Wherein Δ ν is that line width, S/N are signal to noise ratio.Sensitivity for raising magnetic spy instrument must improve Cs atom absorption chamber
The atom line width and signal to noise ratio of magnetic spy instrument can be realized.
It is understood that it will be understood by those skilled in the art that to the technical solution of the utility model and utility model structure
Think of is subject to equivalent substitution or changed all belong to the scope of the claims appended by the utility model.
The overall structure figure of this new caesium optical pumping magnetic spy instrument probe is as shown in Figure 1.In heater 2 and radio frequency induction device 1
Under effect, the caesium Metal gasification in caesium lamp 3, Cs atom is luminous by high frequency pumping, produces the pump light of 894.3nm service bands.
By beam-expanding collimation after Fresnel Lenses 4 into directional light.This new middle polarizer is split beam formula polarizer, and its structure is as schemed
Shown in 2.894.3nm light is changed into left and right rotatory polarization light by it.
Claims (5)
1. a kind of new caesium optical pumping magnetic spy instrument probe device, it is characterised in that：Mainly include radio frequency induction device (1), heater
(2), caesium lamp (3), Fresnel Lenses (4), split beam formula polarizer (5), Cs atom absorption chamber (6), heating coil (7), set
Cylinder (8), thermistor (9), lens (10), optical filter (11), photodiode (12) and shell (13)；In heater (2) and
In the presence of radio frequency induction device (1), the caesium Metal gasification in caesium lamp (3), Cs atom is luminous by high frequency pumping, produces 894.3nm
The pump light of service band, beam-expanding collimation is into directional light afterwards by Fresnel Lenses (4) for pump light, and directional light passes through split beam
Formula polarizer (5) changes into left and right rotatory polarization light, and polarised light produces optical pumping effect inside Cs atom absorption chamber (6)；By adding
Heat coil (7) is heated to Cs atom absorption chamber (6), while thermistor (9) feeds back lamp house temperature, keeps Cs atom absorption chamber
(6) heating-up temperature is stable；Lens (10), optical filter (11) converge at useful optical signal on photodiode (12), photosensitive
Diode (12) converts optical signals into electric signal；Larmor frequency amplify through multipole signal after by the shifting in signal processor
Phase device formation self-oscillation loop, while being counted to Larmor frequency, reads corresponding frequency values, is converted into being presently in position
Magnetic field of the earth；When the RF field frequency produced by the coil on sleeve (8) and Cs atom absorption chamber (6) interior nuclear magnetic resonance
When Larmor frequency is consistent, self-excitation tracking can be formed after the phase shifter phase shift in caesium optical pumping magnetic spy instrument in signal processor.
2. new caesium optical pumping magnetic spy instrument probe device according to claim 1, it is characterised in that：Pass through the temperature in magnetic spy instrument
Control circuit and thermostatic control is carried out to Cs atom absorption chamber (6).
3. new caesium optical pumping magnetic spy instrument probe device according to claim 1, it is characterised in that：Pass through Fresnel Lenses
(4) the work spectral line produced by caesium lamp (3) is expanded into and the big directional light such as Cs atom absorption chamber (6) working face.
4. new caesium optical pumping magnetic spy instrument probe device according to claim 1, it is characterised in that：Cs atom absorption chamber (6)
Buffer gas is filled, the relaxation effect for reducing atom in atomic air chamber improves the sensitivity of magnetic spy instrument；And in the plating of Cs atom absorption chamber
The OTS films of hot operation are adapted to, Atomic absorption room line width is narrowed and improves sensitivity.
5. new caesium optical pumping magnetic spy instrument probe device according to claim 1, it is characterised in that：Caesium lamp (3) is column, bottom
Portion's heater gasifies to the metal in its caesium lamp (3), while encouraging caesium lamp (3) using radio frequency induction mode.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201621423193.2U CN206400119U (en) | 2016-12-23 | 2016-12-23 | A kind of new caesium optical pumping magnetic spy instrument probe device |
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| CN201621423193.2U CN206400119U (en) | 2016-12-23 | 2016-12-23 | A kind of new caesium optical pumping magnetic spy instrument probe device |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108227010A (en) * | 2017-12-29 | 2018-06-29 | 清华大学 | Towards the special caesium optical pumping detector of buried unexploded |
| CN108279438A (en) * | 2017-12-29 | 2018-07-13 | 清华大学 | Special caesium optical pumping detector towards waters day something lost chemical weapons |
| CN108562861A (en) * | 2018-03-30 | 2018-09-21 | 上海通用卫星导航有限公司 | A kind of symmetrical caesium optical pumped magnetometer for magnetic gradient measurements |
| CN111060855A (en) * | 2018-10-17 | 2020-04-24 | 北京自动化控制设备研究所 | High-sensitivity magnetic field measurement method based on width and width of electronic gyromagnetic resonance line |
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2016
- 2016-12-23 CN CN201621423193.2U patent/CN206400119U/en active Active
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108227010A (en) * | 2017-12-29 | 2018-06-29 | 清华大学 | Towards the special caesium optical pumping detector of buried unexploded |
| CN108279438A (en) * | 2017-12-29 | 2018-07-13 | 清华大学 | Special caesium optical pumping detector towards waters day something lost chemical weapons |
| WO2019127840A1 (en) * | 2017-12-29 | 2019-07-04 | 清华大学 | Cesium optically pumped detector specialized for buried abandoned japanese chemical weapons |
| CN108279438B (en) * | 2017-12-29 | 2019-09-20 | 清华大学 | Dedicated caesium optical pumping detector towards waters day something lost chemical weapons |
| US10571532B2 (en) | 2017-12-29 | 2020-02-25 | Tsinghua University | Cesium optical pump detector for buried and abandoned chemical weapons |
| CN108562861A (en) * | 2018-03-30 | 2018-09-21 | 上海通用卫星导航有限公司 | A kind of symmetrical caesium optical pumped magnetometer for magnetic gradient measurements |
| CN108562861B (en) * | 2018-03-30 | 2020-10-16 | 上海通用卫星导航有限公司 | Symmetrical cesium optical pump magnetometer for magnetic gradient measurement |
| CN111060855A (en) * | 2018-10-17 | 2020-04-24 | 北京自动化控制设备研究所 | High-sensitivity magnetic field measurement method based on width and width of electronic gyromagnetic resonance line |
| CN111060855B (en) * | 2018-10-17 | 2022-03-11 | 北京自动化控制设备研究所 | High-sensitivity magnetic field measurement method based on width and width of electronic gyromagnetic resonance line |
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