阅读说明：本技术 一种反射式光路可调cpt原子磁力仪探头 (Reflection type optical path adjustable CPT atomic magnetometer probe ) 是由 王学锋 李明阳 邓意成 刘院省 卢向东 徐强锋 张天宇 李建军 路航 于 2021-08-11 设计创作，主要内容包括：本发明公开一种反射式光路可调CPT原子磁力仪探头,包括探头主结构、偏振分光棱镜、1/4波片、原子气室、原子气室套筒、弹簧导杆、反射棱镜、镜片调节螺钉、镜片挡板、镜片调节弹簧、光纤准直器和弹簧调节螺母。所述偏振分光棱镜、1/4波片、原子气室、光纤准直器和反射棱镜为光学器件,所述光学器件和探头主结构组成反射光路,入射激光经偏振分光棱镜偏转90°,由S光轴输出,输出激光通过1/4波片和原子气室后射入反射棱镜,经反射棱镜反射,激光再次偏转90°,经输出端光纤准直器出射,最终实现出射光路180°偏转。本发明通过偏振分光棱镜和反射棱镜实现反射光路设计,在保证磁力仪测量精度的同时,减小了探头体积,提高了探头的工程适应性。(The invention discloses a reflection type optical path adjustable CPT atomic magnetometer probe, which comprises a probe main structure, a polarization beam splitter prism, 1/4 wave plates, an atomic air chamber sleeve, a spring guide rod, a reflection prism, a lens adjusting screw, a lens baffle, a lens adjusting spring, an optical fiber collimator and a spring adjusting nut. The polarization beam splitter prism, the 1/4 wave plate, the atomic air chamber, the optical fiber collimator and the reflection prism are optical devices, the optical device and the probe main structure form a reflection light path, incident laser is deflected by 90 degrees through the polarization beam splitter prism and is output through an S optical axis, output laser passes through the 1/4 wave plate and the atomic air chamber and then enters the reflection prism, is reflected through the reflection prism, is deflected by 90 degrees again, is emitted through the output end optical fiber collimator, and finally 180-degree deflection of the emission light path is achieved. The invention realizes the design of the reflection light path through the polarization beam splitter prism and the reflection prism, reduces the volume of the probe and improves the engineering adaptability of the probe while ensuring the measurement precision of the magnetometer.)

1. A reflection-type optical path adjustable CPT atomic magnetometer probe is characterized by comprising: the device comprises a probe main structure (1), a polarization beam splitter prism (2), an 1/4 wave plate (3), an atom air chamber (4), an atom air chamber sleeve (5), a reflection prism (6), a spring guide rod (7), a spring adjusting nut (8), a lens baffle (9), a lens adjusting spring (10) and an optical fiber collimator (11);

the number of the atomic gas chamber sleeves (5) is 2, and the atomic gas chambers are clamped at two sides of the atomic gas chamber (4) along the axial direction; the probe main structure (1) is an installation carrier of all other parts; the polarization beam splitter prism (2), the atom air chamber sleeve (5) and the reflection prism (6) are fixedly adhered inside the probe main structure; the 1/4 wave plate (3) is adhered to the surface of the polarization beam splitter prism (2); external threads are arranged at two ends of the spring guide rod (7) and used for installing and fixing a spring adjusting nut (8); the lens baffle (9) is provided with a guide hole for penetrating through the spring guide rod (7); the diameter of the guide hole is larger than the outer diameter of the spring guide rod (7), and the diameter of the guide hole is smaller than the inner diameter of the spring, so that the guide hole penetrates through the spring guide rod (7) and limits the lens adjusting spring (10) through the two lens baffles (9); the spring adjusting nut (8) is used for fixedly connecting the lens baffle plates (9) and the lens adjusting spring (10) on the spring guide rod (7) through threads, and the distance between the lens baffle plates (9) is adjusted by rotating the spring adjusting nut (8); the outer diameter of the spring adjusting nut (8) is larger than the guide holes of the lens baffles (9) and is used for limiting the two lens baffles (9); the lens adjusting spring (10) penetrates through the spring guide rod (7); the optical fiber collimator (11) is arranged on the same side of the probe main structure (1), and the cable enters and exits the probe from the same side;

incident laser deflects 90 degrees through the polarization beam splitter prism (2), is output by the S optical axis by P axle output change, and output laser penetrates 1/4 wave plate (3), atom air chamber (4) and reflecting prism (6) in proper order, reflects through reflecting prism (6), and laser deflection 90 degrees is emergent through output end fiber collimator (11), finally realizes 180 degrees deflections of emergent light path.

2. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: also comprises a lens adjusting screw (12); threaded holes are designed on the vertical mounting surfaces of the polarization splitting prism (2) and the reflecting prism (6); the lens adjusting screw (8) is arranged in the threaded hole, and the distance between the polarization beam splitter prism (2) and the reflecting prism (6) is adjusted by rotating the lens adjusting screw (12) and the spring adjusting nut (8), so that the light path is adjusted.

3. A reflective optical path tunable CPT atomic magnetometer probe according to claim 2, characterized in that: the lens adjusting screw (12) and the spring adjusting nut (8) adopt fine threads so as to improve the adjusting precision.

4. A reflective optical path tunable CPT atomic magnetometer probe according to claim 2, characterized in that: the probe main structure (1), the lens adjusting screw (12), the lens baffle (9), the spring guide rod (7), the spring adjusting nut (8) and the lens adjusting spring (10) are all made of nonmagnetic metal so as to reduce residual magnetism of the probe and avoid interference with a magnetic field measurement result.

5. A reflective optical path tunable CPT atomic magnetometer probe according to claim 2, characterized in that: the surface of the probe main structure (1), the lens adjusting screw (12), the lens baffle (9), the spring guide rod (7) and the spring adjusting nut (8) is blackened, so that laser is prevented from leaking in the probe structure, and the laser is reflected back to the laser to burn out a chip.

6. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: the polarization beam splitter prism (2), the 1/4 wave plate (3), the atomic gas chamber (4), the reflecting prism (6) and the optical fiber collimator (11) are used as optical devices; the probe main structure (1) is used as a mounting carrier of the optical device; the optical device and the probe main structure (1) form a reflection light path; the lens adjusting mechanism comprises a lens adjusting screw (12), a lens baffle (9), a lens adjusting spring (10), a spring guide rod (7) and a spring adjusting nut (8).

7. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: the lens adjusting spring (10) penetrates out of the spring guide rod (7), is in a compressed state, and applies outward thrust to the 1/4 wave plate (3) and the reflecting prism (6) through the two lens baffles (9).

8. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: the lens baffle (9) is also provided with a light through hole, the aperture of the light through hole is smaller than the outer diameter of the 1/4 wave plate (3), so that a light path is not blocked, and meanwhile, external force can act on the 1/4 wave plate (3) and the reflecting prism (6).

9. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: the atomic gas chamber (4) is a hollow cylindrical glass shell structure, and the bottom surface of the cylinder is a light-passing surface.

10. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: the atom gas chamber (4) is filled with alkali metal atoms for sensitive magnetic field signals.

11. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: the atom air chamber (4) is filled with buffer gas.

12. A reflective optical path tunable CPT atomic magnetometer probe according to claim 1, characterized in that: all right-angle surfaces of the polarization beam splitter prism (2) are plated with antireflection films; the inclined plane of the reflecting prism (6) is plated with a metal high-reflection film.

Technical Field

The invention relates to a reflection-type optical path adjustable CPT atomic magnetometer probe, and belongs to the technical field of CPT atomic magnetometers.

Background

The magnetic field measurement can be applied to the scientific and technological and civil fields of mineral exploration, earth magnetic map mapping, navigation positioning, medical care and the like. The CPT (coherent population tracking) atomic magnetometer has the characteristics of high precision, low energy consumption and good long-term stability, and becomes the research focus in the field of current magnetic field measurement.

The CPT atomic magnetometer achieves magnetic field measurement by measuring the energy level split spacing which is proportional to the magnitude of the external magnetic field. The CPT atomic magnetometer consists of a probe, an electronic box and a connecting wire (optical) cable. The probe is a magnetic field signal acquisition component, the wire (optical) cable is a magnetic field signal transmission component, and the electronic box is a magnetic field signal demodulation component. The performance of the probe has great influence on indexes such as precision, noise and the like of the magnetometer, and the probe is a core component of the CPT atomic magnetometer.

At present, CPT atomic magnetometer probe is correlation coaxial-type cylinder, and line (light) cable stretches out from probe both ends, links back the electronic box after the bending again, and the very big increase of return bend optical cable has the outline size of probe, and the optical cable of bending part is in unsettled state, need additionally protect it during the use, not only the operation is complicated, and reliability and environmental suitability are relatively poor moreover, can not satisfy most engineering application demands. In addition, the optical path coupling efficiency of the correlation coaxial probe is related to the machining precision, and the optical device cannot be adjusted after being assembled. Therefore, it is necessary to provide a probe structure with small volume, strong engineering applicability and adjustable optical path.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the defects of the prior art, the reflective CPT atomic magnetometer probe with the adjustable optical path is provided, so that the optical cable extends out from the same side of the probe, the optical cable is prevented from being bent, the volume of the probe is reduced, the laying difficulty is reduced, the adjustability of the optical path is increased, the fault tolerance during machining and assembling is improved, and the CPT atomic magnetometer has excellent measurement precision and better engineering applicability.

The technical solution of the invention is as follows: a reflection type optical path adjustable CPT atomic magnetometer probe comprises a polarization beam splitter prism, an 1/4 wave plate, an atomic air chamber, an optical fiber collimator, a probe main structure, a reflection prism, a lens adjusting screw, a lens baffle, a lens adjusting spring, a spring guide rod and a spring adjusting nut. The optical path adjusting mechanism comprises a polarization beam splitter prism, a 1/4 wave plate, an atomic air chamber and an optical fiber collimator, wherein the 1/4 wave plate is fixedly adhered to the surface of the polarization beam splitter prism, the 1/4 wave plate, the atomic air chamber and the optical fiber collimator are optical devices, the main probe structure is an installation carrier of the optical devices, the optical devices and the main probe structure form a reflection optical path, and the lens adjusting screws, a lens baffle, a lens adjusting spring, a spring guide rod and a spring adjusting nut form a light path adjusting mechanism.

The reflection type is a reflection light path composed of a polarization beam splitter prism and a reflection prism, incident laser deflects 90 degrees through the polarization beam splitter prism, the output of the polarization beam splitter prism is changed from P axis to S axis, output laser sequentially enters 1/4 wave plates, an atomic gas chamber and the reflection prism, is reflected by the reflection prism, the laser deflects 90 degrees, is emitted through an output end optical fiber collimator, and finally the 180-degree deflection of the emission light path is realized.

And all right-angle surfaces of the polarization beam splitter prism are plated with antireflection films.

The inclined plane of the reflecting prism is plated with a metal high-reflection film.

The optical fiber collimator is arranged on the same side of the probe main structure, and the cable enters and exits the probe from the same side, so that the wiring and the installation of the optical fiber collimator are more convenient, and the engineering applicability is improved.

And external threads are arranged at two ends of the spring guide rod and used for arranging and fixing the spring adjusting nut.

The lens adjusting spring penetrates through the spring guide rod and is used for applying internal stress.

The lens baffle is provided with a guide hole for penetrating the spring guide rod, and the lens adjusting spring is limited by the two lens baffles.

The lens baffle is provided with a light through hole, the aperture of the light through hole is smaller than the outer diameter of the 1/4 wave plate, so that a light path can pass through the light through hole without being blocked, and meanwhile, external force can act on the 1/4 wave plate and the reflecting prism.

The spring adjusting nut fixes the lens baffle and the lens adjusting spring on the spring guide rod through threaded fastening connection, and the distance between the lens baffles is adjusted through rotating the nut.

Threaded holes are formed in the vertical mounting surfaces of the polarization splitting prism and the reflecting prism of the probe structure, the lens adjusting screws are mounted in the threaded holes, and the adjustment of the distance between the polarization splitting prism and the reflecting prism is achieved by rotating the lens adjusting screws.

The probe main structure, the lens adjusting screw, the lens baffle, the spring guide rod and the spring adjusting nut are made of nonmagnetic metal such as aluminum alloy or titanium alloy and the like, so that the residual magnetism of the probe is reduced, and the interference on the measurement result of a magnetic field is avoided.

The lens adjusting spring is made of beryllium bronze alloy and other non-magnetic metals and is used for reducing the residual magnetism of the probe and avoiding interfering the measurement result of the magnetic field.

The lens adjusting spring is in a compressed state after being assembled, so as to provide internal pretightening force, and the two lens baffles apply outward thrust to the 1/4 wave plate and the reflection prism.

The surfaces of the probe main structure, the lens adjusting screw, the lens baffle, the spring guide rod and the spring adjusting nut are blackened, so that laser is prevented from leaking in the probe structure, and the laser is reflected back to the laser to burn out a chip.

The lens adjusting screw and the spring adjusting nut are fine threads, so that the adjusting precision is improved.

The atomic gas chamber sleeve is made of plastic with high and low temperature resistance, good heat preservation performance and excellent mechanical performance, such as polyimide plastic.

The atomic air chamber sleeve adopts a 'wave edge' design to reduce the heat conduction area and improve the heat insulation performance.

The atomic gas chamber is of a hollow cylindrical glass shell structure, and the upper bottom surface and the lower bottom surface are smooth surfaces.

The atom gas chamber is filled with alkali metal atoms, such as rubidium atoms, and is used for sensing magnetic field signals.

The atom gas chamber is filled with buffer gas such as helium, nitrogen and the like, and is used for improving the atom polarizability.

Compared with the prior art, the invention has the beneficial effects that:

(1) the reflection type optical path adjustable CPT atomic magnetometer probe provided by the invention realizes the design of a reflection optical path by using the polarization beam splitter prism and the reflection prism, so that the incident optical cable and the emergent optical cable are positioned at the same side of the probe, the problem of optical cable bending in the current correlation coaxial probe is avoided, the volume of the probe is reduced, the laying difficulty is reduced, and the engineering applicability is improved.

(2) The reflection type light path adjustable CPT atomic magnetometer probe provided by the invention uses the lens adjusting screw, the lens baffle, the lens adjusting spring, the spring guide rod and the spring adjusting nut to form the light path adjusting mechanism, so that an optical device in the probe can be adjusted, the fault tolerance during machining and assembling is improved, and the measurement precision of the CPT atomic magnetometer is ensured.

(3) The reflection type light path adjustable CPT atomic magnetometer probe has the advantages of strong engineering applicability, small machining difficulty, high assembly fault tolerance and better economic benefit.

Drawings

FIG. 1 is a top view of a reflective optical path adjustable CPT atomic magnetometer probe;

FIG. 2 is an oblique view of a reflection type optical path adjustable CPT atomic magnetometer probe;

fig. 3 is an oblique view of the optical path adjusting structure.

Detailed Description

The technical solutions in the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The invention aims to provide a reflection type optical path adjustable CPT atomic magnetometer probe, so that the CPT atomic magnetometer has excellent measurement precision and better engineering applicability.

Referring to fig. 1 to 3, an embodiment of the present invention provides a reflection type optical path adjustable CPT atomic magnetometer probe, which includes a probe main structure 1, a polarization splitting prism 2, an 1/4 wave plate 3, an atomic gas chamber 4, an atomic gas chamber sleeve 5, a reflection prism 6, a spring guide rod 7, a spring adjusting nut 8, a lens baffle 9, a lens adjusting spring 10, an optical fiber collimator 11, and a lens adjusting screw 12.

The reflection type is a reflection light path composed of a polarization beam splitter prism 2 and a reflection prism 6, incident laser is deflected by 90 degrees through the polarization beam splitter prism 2, the output of the P axis is changed into the output of the S axis, and the output laser sequentially enters 1/4 wave plates 3, atomic gas chambers 4 and the reflection prism 6. The laser is reflected by the reflecting prism 6, deflected by 90 degrees and emitted by the output end optical fiber collimator 11, and finally the 180-degree deflection of the emergent light path is realized.

The number of the atom cell sleeves 5 is 2, and the atom cell sleeves are clamped on two sides of the atom cell 4 along the axial direction.

The main structure 1 of the probe is an installation carrier of all other parts, and the polarization beam splitter prism 2, the atomic gas chamber sleeve 5 and the reflection prism 6 are adhered inside the main structure of the probe.

The polarization splitting prism 2 and the 1/4 wave plate 3 are cemented together.

And all right-angle surfaces of the polarization beam splitter prism 2 are coated with antireflection films.

The inclined plane of the reflecting prism is plated with a metal high-reflection film.

The optical fiber collimator 11 is arranged on the same side of the probe main structure 1, and the cable enters and exits the probe from the same side, so that the wiring and the installation of the optical fiber collimator are more convenient, and the engineering applicability is improved.

And external threads are arranged at two ends of the spring guide rod 7 and used for arranging and fixing a spring adjusting nut 8.

The lens adjusting spring 10 penetrates the spring guide 7 for applying internal stress.

The lens baffle 9 is provided with a guide hole for passing through the spring guide rod 7, and the lens adjusting spring 10 is limited by the two lens baffles 7.

The lens baffle is provided with a light through hole, the aperture of the light through hole is smaller than the outer diameter of the 1/4 wave plate 3, so that a light path can pass through the light through hole without being blocked, and meanwhile, external force can act on the 1/4 wave plate 3 and the reflecting prism 6.

The spring adjusting nut 8 fixes the lens baffle 9 and the lens adjusting spring 10 on the spring guide rod 7 through screw fastening connection, and the distance between the lens baffle 9 is adjusted by rotating the spring adjusting nut 8.

Threaded holes are designed on the vertical mounting surfaces of the polarization splitting prism 2 and the reflecting prism 6 in the probe main structure 1, the lens adjusting screws 13 are mounted in the threaded holes, and the adjustment of the distance between the polarization splitting prism 2 and the reflecting prism 6 is realized by rotating the lens adjusting screws 13.

The probe main structure 1, the lens adjusting screw 13, the lens baffle 9, the spring guide rod 7 and the spring adjusting nut 8 are made of nonmagnetic metal such as aluminum alloy or titanium alloy and the like, so that the residual magnetism of the probe is reduced, and the magnetic field measurement precision is improved.

The lens adjusting spring 10 is made of non-magnetic metal such as beryllium bronze alloy and the like, and is used for reducing the residual magnetism of the probe and improving the measurement precision of a magnetic field.

The lens adjustment spring 10 is in a compressed state after assembly to provide internal pre-tightening force.

The surfaces of the probe main structure 1, the lens adjusting screw 13, the lens baffle 9 and the spring guide rod 7 are blackened, so that laser is prevented from leaking in the probe structure, and the laser is reflected back to the laser to burn out a chip.

The lens adjusting screw 13 and the spring adjusting nut 8 are fine threads to improve the adjusting accuracy.

The atomic gas chamber sleeve 5 is made of plastic with high and low temperature resistance, good heat preservation performance and excellent mechanical performance, such as polyimide plastic.

The atomic gas chamber sleeve 5 adopts a 'wave edge' design, so that the heat conduction area can be reduced, and the heat insulation performance is improved.

The atomic gas chamber 4 is a hollow cylindrical glass shell structure, and the upper bottom surface and the lower bottom surface are light-passing surfaces.

The atom gas chamber 4 is filled with alkali metal atoms, such as rubidium atoms, for sensitive magnetic field signals.

The inside of the atom gas chamber 4 is filled with buffer gas such as helium, nitrogen, etc. for improving the atomic polarizability.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make modifications and variations of the present invention without departing from the spirit and scope of the present invention.