CN110260200B

CN110260200B - Open type integrated small rubidium spectrum lamp for small rubidium atomic frequency standard

Info

Publication number: CN110260200B
Application number: CN201910493561.2A
Authority: CN
Inventors: 王晨; 王鹏飞; 赵峰; 梅刚华
Original assignee: Wuhan Institute of Physics and Mathematics of CAS
Current assignee: Jiangyin Tongxiang Technology Co ltd; Institute of Precision Measurement Science and Technology Innovation of CAS
Priority date: 2019-06-06
Filing date: 2019-06-06
Publication date: 2021-03-05
Anticipated expiration: 2039-06-06
Also published as: CN110260200A

Abstract

The invention discloses an open type integrated small rubidium spectrum lamp for a small rubidium atomic frequency standard, which comprises a bulb and a lamp holder, wherein a coil framework mounting through hole is formed in the lamp holder, a conical clamping seat is arranged at the inner end of the coil framework mounting through hole, a coil framework is arranged in the coil framework mounting through hole, the outer wall of the coil framework is attached to the inner wall of the coil framework mounting through hole, an internal thread is arranged on the inner wall of the coil framework, an oscillating coil is embedded in the internal thread of the inner wall of the coil framework, the bulb tail is arranged in the conical clamping seat, the oscillating coil is electrically connected with an excitation PCB, the lamp holder is fixed with a heat insulation gasket, a sapphire glass sheet is arranged at the outer end of the coil framework mounting through hole, a heating pipe is. The invention can meet the design requirements of small volume, low working temperature and high reliability. The method has the advantages of simple debugging, good process consistency and convenience for batch production, and can be used for large and medium batch production of the miniaturized rubidium frequency standard.

Description

Open type integrated small rubidium spectrum lamp for small rubidium atomic frequency standard

Technical Field

The invention belongs to the field of rubidium spectrum lamps, and particularly relates to an open type integrated small rubidium spectrum lamp for a small rubidium atomic frequency standard. The rubidium spectrum lamp is applied to a miniaturized rubidium atomic frequency standard with strict requirements on volume, and the rubidium spectrum lamp is convenient to debug and install due to the open and integrated structure.

Background

As a pumping light source of a physical system, a rubidium spectrum lamp is one of key components of a rubidium atomic frequency standard, and the performance of the rubidium spectrum lamp has an influence on the overall performance of the rubidium atomic frequency standard. In order to meet the design requirement of rubidium atomic frequency standard miniaturization, the size of a rubidium spectral lamp needs to be reduced.

The rubidium spectrum lamp utilizes the principle of electrodeless discharge luminescence of rubidium metal gas. The exciting circuit generates a radio frequency signal of about 100MHz to excite the starting gas in the bulb to ionize, and the starting gas ions and⁸⁷the Rb vapor atoms collide, exciting the latter to emit light. The bulb is filled with⁸⁷The Rb vapor and the starting gas are in a radio frequency field generated by the oscillating coil. The excitation circuit selects a Clapp oscillation circuit with simple circuit structure and good oscillation frequency and amplitude stability, the oscillation tube is packaged by a patch, and is integrated on the excitation PCB board together with other patch elements and installed on the lamp holder.

The rubidium spectral lamp emits light with the working substance being rubidium vapor atoms. In order to achieve a sufficient rubidium atom vapor density, the rubidium bulb needs to be heated. Meanwhile, in order to ensure the stability of the light intensity of the spectrum lamp, the density of rubidium vapor atoms is also very stable, so that the rubidium bulb needs to be designed at a constant temperature. However, since the operating temperature of the lamp is high and the rubidium spectrum lamp is small in size, the heat accumulation effect is likely to occur, and therefore, it is necessary to consider reasonable heat dissipation of the spectrum lamp.

Disclosure of Invention

The invention aims to solve the problems in the prior art, provides an open type integrated small rubidium spectrum lamp for a miniaturized rubidium atomic frequency standard, has a compact structure, is convenient to debug, install and replace, and can meet the design requirements of small volume, low working temperature and high reliability of a physical system pumping light source of the miniaturized rubidium atomic frequency standard. The design also has the advantages of simple debugging, good process consistency and convenient batch production, and can be used for large and medium batch production of the miniaturized rubidium frequency standard.

The open type integrated small rubidium spectrum lamp for the miniaturized rubidium atomic frequency standard comprises a bulb and a lamp holder, wherein a coil framework mounting through hole is formed in the lamp holder, a conical clamping seat is arranged at the inner end of the coil framework mounting through hole, a first wire outlet seam is formed in the hole wall of the coil framework mounting through hole, a coil framework is arranged in the coil framework mounting through hole and is cylindrical, a second wire outlet seam corresponding to the first wire outlet seam in position is formed in the side wall of the coil framework, the outer wall of the coil framework is attached to the inner wall of the coil framework mounting through hole, internal threads are formed in the inner wall of the coil framework, an oscillating coil is embedded in the internal threads of the inner wall of the coil framework, the bulb comprises a bulb body and a bulb tail integrally arranged with the bulb body, the bulb tail is arranged in the conical clamping seat, silica gel is coated between the bulb tail and the conical clamping seat, and the, the two ends of the oscillating coil are respectively connected with one ends of the two coil leads, the other ends of the two coil leads sequentially penetrate through the second outgoing line seam and the first outgoing line seam to be electrically connected with the excitation PCB, the excitation PCB is fixed on the lamp holder, the lamp holder is fixed with the heat insulation gasket, the outer end of the coil skeleton mounting through hole is provided with a sapphire glass sheet, the heat insulation gasket is connected with the lamp holder side vertical plate, the bottom of the lamp holder side vertical plate is integrally connected with the lamp holder, the heating pipe is arranged on the lamp holder, a temperature sensing element mounting hole is formed in the lamp holder, and a temperature sensing element is arranged in the temperature sensing.

The excitation PCB board is provided with an excitation circuit, the excitation circuit comprises an oscillating tube, a first resistor R1, a second resistor R2, a third resistor R3, a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5 and a diode D1,

the collector of the oscillation tube is respectively connected with one end of a fourth capacitor C4, one end of a fifth capacitor C5, one end of a first resistor R1 and a power supply VCC, and the other end of the fourth capacitor C4 and the other end of the fifth capacitor C5 are electrically connected with the ground;

the base of the oscillation tube is connected with one end of a second capacitor C2, one end of a third capacitor C3 and one end of a second inductor L2, the other end of the second capacitor C2 is respectively connected with the emitter of the oscillation tube 5 and one end of a third resistor R3, the other end of the third resistor R3 is electrically connected with the ground through a first inductor L1, the other end of the third capacitor C3 is electrically connected with the ground through an oscillation coil 3, the other end of the second inductor L2 is connected with the other end of a first resistor R1, one end of a second resistor R2 and one end of a first capacitor C1, the other end of the first capacitor C1 is electrically connected with the ground, the other end of the second resistor R2 is connected with the anode of a diode D1, the cathode of the diode D1 is electrically connected with the ground, and the third capacitor C3.

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

1. a small-sized bulb is used. The luminous intensity of spectrum lamp is related to the size of bulb, and the size of the bulb has been reduced to the size of taking into account miniaturized rubidium frequency scale absorption bubble and the size of filtering bubble less, and the bulb external diameter of selecting for use is 6mm, and the bulb body length is 8mm, and bulb tail length is 5mm, and bulb wall thickness is 0.6 mm. Because the size of the bulb is small, the radio frequency energy required for exciting the bulb to emit light is small, the wall thickness of the bulb is thin, and the efficiency of coupling energy from a radio frequency field is higher;

2. the design that the bulb is separated from the oscillating coil is adopted. When the spectrum lamp works, a large alternating current exists in the oscillating coil, a heating effect is inevitably generated on the rubidium bulb, and the situations that a heating circuit fails and the temperature of the lamp is difficult to control are possibly caused. In order to reduce the influence of the part of heat on the temperature of the bulb, the oscillating coil is fixed on the coil framework instead of being directly wound on the bulb, so that the physical separation of the coil and the bulb is realized, and the phenomenon of excessive heat accumulation on the bulb is avoided;

3. the coil frame is designed into an internal thread structure. In general, an oscillating coil of a rubidium spectrum lamp adopts a close winding mode, and the inner diameter of a solenoid is the outer diameter of a bulb. This winding method not only has poor consistency, but also has the possibility of deformation of the tightly wound solenoid as the service time of the rubidium spectrum lamp increases. The equivalent inductance value determined by the shape of the oscillating coil is an important parameter in the oscillating circuit, and can greatly influence the stability of the excitation frequency and the excitation power, and thus the stability of the light emission of the spectrum lamp. According to the invention, the coil framework is designed into an internal thread structure, the depth and the distance of the wire grooves are fixed values, and the structural parameters of the oscillating coil formed by winding are consistent in height, so that the consistency of design and assembly is ensured, the debugging of an excitation circuit is more convenient and efficient, the equivalent inductance value is determined, and the bulb can reach the optimal coupling state only by correspondingly adjusting the capacitance value;

4. the lamp holder adopts an L-shaped structural design, and the heating pipe is arranged on the lamp holder to heat the lamp holder instead of the whole lamp body, so that the heat power consumption is reduced. The rubidium spectral lamp emits light as an operating substance of rubidium vapor atoms, and a rubidium bulb needs to be heated in order to form a sufficient rubidium atom vapor density, and a normal operating temperature is around 100 ℃. The lamp holder is made of aluminum alloy materials and is designed into an L-shaped structure, the conical clamping seat is used for mounting a bulb, as shown in fig. 5, the part extending out of the right side of the lamp holder is used for mounting a heating pipe, and the temperature sensing element mounting hole on the left side is used for mounting a temperature sensing element. The design can realize the heating of the heating pipe to the lamp holder in a small range, and the heat is conducted to the bulb, so that the heating power consumption can be reduced, and the temperature control of the bulb can be more real and accurate. The coil framework made of the low-thermal-conductivity material is arranged on the outer side of the bulb, and the sapphire glass sheet is arranged at the light through hole, so that the bulb can be effectively insulated. Meanwhile, a heat insulation gasket is designed between the lamp holder and the side wall of the lamp holder to play a certain role in heat preservation;

5. the excitation circuit is well grounded, and the stability and the better anti-interference capability of the excitation circuit are ensured. The excitation PCB is arranged at the bottom of the lamp holder through four screws, so that the stability of the ground potential of the circuit is ensured, the frequency spectrum quality of an excitation signal is improved, and the influence on the stability of light intensity is avoided;

6. the lamp holder is of an open design rather than a closed housing design. In order to meet the requirements of large and medium-scale mass production of miniaturized rubidium atomic frequency standard, an open lamp holder design is adopted, and a key oscillation parameter device on an excitation PCB is placed on an open position on a board, so that the parameters are convenient to debug and optimize, and meanwhile, the problem that a lamp holder and a coil are difficult to install in a closed shell design is avoided.

Drawings

FIG. 1 is a cross-sectional view of the present invention;

FIG. 2 is a perspective view of the present invention;

FIG. 3 is a perspective view of a bobbin;

FIG. 4 is a cross-sectional view of the bobbin;

FIG. 5 is a perspective view of the lamp head;

FIG. 6 is a front view of the lamp head;

FIG. 7 is a schematic diagram of a drive circuit;

fig. 8 is an ac equivalent circuit of the excitation circuit.

Wherein: 1-a bulb; 2-a lamp holder; 3-an oscillating coil; 4-a coil skeleton; 5-oscillating tube; 6-exciting the PCB; 7-a lamp holder; 8-heat insulating spacer; 9-sapphire glass sheet; 10-heating a tube; 11-adapting the PCB; 12-coil leads; 13-temperature sensing element mounting holes; 14-coil framework mounting through holes; 15-first seam outlet; 16-second seam; 17-lamp holder side vertical plate.

Detailed description of the invention

The present invention will be described in further detail with reference to examples for the purpose of facilitating understanding and practice of the invention by those of ordinary skill in the art, and it is to be understood that the present invention has been described in the illustrative embodiments and is not to be construed as limited thereto.

As shown in fig. 1, the open type integrated compact rubidium spectrum lamp for the compact rubidium atomic frequency standard comprises a bulb 1, a lamp holder 2, an oscillating coil 3, a coil skeleton 4, an oscillating tube 5, an excitation PCB 6, a lamp holder 7, a heat insulation gasket 8, a sapphire glass sheet 9, a heating tube 10, a switching PCB 11, a coil lead 12 and a temperature sensing element mounting hole 13.

A coil framework mounting through hole 14 is arranged in the lamp holder 2, a conical clamping seat is arranged at the inner end of the coil framework mounting through hole 14, a first seam 15 is arranged on the hole wall of the coil framework mounting through hole 14, a coil framework 4 is arranged in the coil framework mounting through hole 14, the coil framework 4 is cylindrical, a second seam 16 corresponding to the first seam 15 is arranged on the side wall of the coil framework 4, the outer wall of the coil framework 4 is attached to the inner wall of the coil framework mounting through hole 14, inner threads are arranged on the inner wall of the coil framework 4, an oscillating coil 3 is embedded in the inner threads on the inner wall of the coil framework 4, the bulb 1 comprises a bulb body and a bulb tail integrated with the bulb body, the bulb tail is arranged in the conical clamping seat, silica gel is coated between the bulb tail and the conical clamping seat, when the bulb 1 is mounted, the bulb tail is embedded in the silica gel on the inner wall of the, namely, the bulb 1 is mounted and fixed. The bulb body is located coil skeleton 4, the both ends of oscillating coil 3 are connected with two coil lead wire 12 one end respectively, the other end of two coil lead wire 12 all runs through second play seam 16 and first play seam 15 and encourages PCB board 6 electric connection in proper order, encourage PCB board 6 to install on lamp stand 7 through 4M 2's button head screw, oscillating tube 5 is the paster encapsulation, integrate on encourages PCB board 6 together with other paster component, the side (the trailing flank in fig. 2) of lamp holder 2 that the toper cassette is located is fixed with heat insulating gasket 8, the outer end of coil skeleton mounting hole 14 is provided with sapphire glass piece 9, heat insulating gasket 8 is connected with lamp holder side riser 17, the bottom and the lamp stand 7 integration of lamp holder side riser 17 are connected, be provided with heating pipe 10 on the lamp holder 2. The lamp holder 2 is provided with a temperature sensing element mounting hole 13, a temperature sensing element is arranged in the temperature sensing element mounting hole 13, the temperature sensing element is electrically connected with the switching PCB 11 through a lead, and the switching PCB 11 monitors the temperature.

In this embodiment, the bulb 1 has an outer diameter of 6mm, a length of 8mm, a length of 5mm and a wall thickness of 0.6 mm.

The excitation PCB 6 is provided with an excitation circuit, and the excitation circuit comprises a power triode Q1 (namely an oscillating tube 5), a first resistor R1, a second resistor R2, a third resistor R3, a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5 and a diode D1.

A collector of the power transistor Q1 is respectively connected to one end of a fourth capacitor C4, one end of a fifth capacitor C5, one end of a first resistor R1 and a power supply VCC, and the other end of the fourth capacitor C4 and the other end of the fifth capacitor C5 are electrically connected to ground;

the base of the power triode Q1 is connected with one end of a second capacitor C2, one end of a third capacitor C3 and one end of a second inductor L2, the other end of the second capacitor C2 is respectively connected with the emitter of the power triode Q1 and one end of a third resistor R3, the other end of the third resistor R3 is electrically connected with the ground through the first inductor L1, the other end of the third capacitor C3 is electrically connected with the ground through the oscillating coil 3, the other end of the second inductor L2 is connected with the other end of a first resistor R1, one end of the second resistor R2 and one end of the first capacitor C1, the other end of the first capacitor C1 is electrically connected with the ground, the other end of the second resistor R2 is connected with the anode of a diode D1, and the cathode of the diode D1 is electrically connected.

The third capacitor C3 is an adjustable capacitor. Both ends of the oscillation coil 3 are connected to an electric ground and a third capacitor C3 through two coil leads 12, respectively.

The exciting circuit of the exciting PCB 6 adopts a Clapp oscillating circuit with simple circuit structure and good stability of oscillation frequency and amplitude, and an alternating current equivalent circuit of the Clapp oscillating circuit is shown in figure 8. The bulb body of the bulb 1 is placed in an inductor (i.e., an oscillating coil 3) formed by winding enameled wires. The direct current bias circuit formed by the first resistor R1, the second resistor R2, the diode D1 and the third resistor R3 sets a proper static operating point for the oscillating tube. The inter-electrode capacitance Cce of the oscillation tube, the second capacitance C2, the third capacitance C3, and the oscillation coil 3 constitute a resonance circuit. The oscillating tube 5 is packaged by a patch, so that the volume of the PCB is reduced, and the structure of the spectrum lamp is more compact.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims

1. The open type integrated small rubidium spectrum lamp for the miniaturized rubidium atomic frequency standard comprises a bulb (1) and is characterized by further comprising a lamp holder (2), a coil framework installation through hole (14) is formed in the lamp holder (2), a conical clamping seat is arranged at the inner end of the coil framework installation through hole (14), a first wire outlet seam (15) is formed in the hole wall of the coil framework installation through hole (14), a coil framework (4) is arranged in the coil framework installation through hole (14), the coil framework (4) is cylindrical, a second wire outlet seam (16) corresponding to the first wire outlet seam (15) in position is formed in the side wall of the coil framework (4), the outer wall of the coil framework (4) is attached to the inner wall of the coil framework installation through hole (14), internal threads are formed in the inner wall of the coil framework (4), an oscillating coil (3) is embedded in the internal threads in the inner wall of the coil framework (4), the bulb (1) comprises a bulb body and a bulb tail integrated with the bulb body, the bulb tail is arranged in a conical clamping seat, silica gel is coated between the bulb tail and the conical clamping seat, the bulb body is positioned in a coil framework (4), two ends of an oscillating coil (3) are respectively connected with one ends of two coil leads (12), the other ends of the two coil leads (12) sequentially penetrate through a second line outgoing seam (16) and a first line outgoing seam (15) to be electrically connected with an excitation PCB (6), the excitation PCB (6) is fixed on a lamp seat (7), a lamp holder (2) is fixed with a heat insulation gasket (8), a sapphire glass sheet (9) is arranged at the outer end of a coil framework installation through hole (14), the heat insulation gasket (8) is connected with a lamp seat side vertical plate (17), the bottom of the lamp seat side vertical plate (17) is integrally connected with the lamp seat (7), a heating pipe (10) is arranged on the lamp holder (2), a temperature sensing element mounting hole (13) is formed in the lamp holder (2), a temperature sensing element is arranged in the temperature sensing element mounting hole (13), and the bulb is separated from the oscillating coil.

2. The open type integrated mini rubidium spectrum lamp for mini rubidium atomic frequency standard according to claim 1, wherein the excitation PCB (6) is provided with an excitation circuit, the excitation circuit comprises an oscillation tube (5), a first resistor (R1), a second resistor (R2), a third resistor (R3), a first inductor (L1), a second inductor (L2), a first capacitor (C1), a second capacitor (C2), a third capacitor (C3), a fourth capacitor (C4), a fifth capacitor (C5), and a diode (D1),

the collector of the oscillation tube (5) is respectively connected with one end of a fourth capacitor (C4), one end of a fifth capacitor (C5), one end of a first resistor (R1) and a power supply VCC, and the other end of the fourth capacitor (C4) and the other end of the fifth capacitor (C5) are electrically connected with the ground;

the base of the oscillation tube (5) is connected with one end of a second capacitor (C2), one end of a third capacitor (C3) and one end of a second inductor (L2), the other end of the second capacitor (C2) is respectively connected with the emitter of the oscillation tube (5) and one end of a third resistor (R3), the other end of the third resistor (R3) is electrically connected with the ground through a first inductor (L1), the other end of the third capacitor (C3) is electrically connected with the ground through an oscillation coil (3), the other end of the second inductor (L2) is connected with the other end of a first resistor (R1), one end of a second resistor (R2) and one end of a first capacitor (C1), the other end of the first capacitor (C1) is electrically connected with the ground, the other end of the second resistor (R2) is connected with the anode of a diode (D1), the cathode of the diode (D1) is electrically connected with the ground, and the third capacitor (C3) is an adjustable capacitor.