CN2403011Y - Active neodymium atom resonance optical filter - Google Patents

Abstract

The utility model discloses an active rubidium atom resonance optical filter, which relates to the optics, the radio electronics, the atom physics, and the molecular physics and is particularly suitable for optical filtering elements for laser communication. In order to provide a high effective and applicable rubidium atom resonance optical filter (Rb-ARF), the utility model is mainly composed of a stepless discharge Rb spectrum lamp and an atomic vapor bubble, wherein, gas such as H2 and CO with proper pressure is added in the vapor bubble. Because the utility model has the advantages of simple structure, small volume and light weight, the active rubidium atom resonance optical filter has narrow band and highest luminous transmittance.

Description

A kind of active rubidium atom resonance light filter

(rubidium-Rb, atom resonance light filter-ARF) relate to optics, radio electronics and atom, molecular physics is particularly useful for the filtering device in the laser communication to a kind of active rubidium atom resonance light filter of the utility model.

Filtering device is widely used in the laser communication, and the situation of prior art is:

1. traditional optical filter is because wide bandwidth and low transmitance can not be satisfied with the requirement that laser communication works by day.

2. the Rb-ARF that has studied and demonstrated, one is to use dye laser or semiconductor laser as exciting the pumping source of Rb ground state atom to 5P excited state, does not also have practicality; Two are to use pure Rb sample, and conversion efficiency is lower.The active Rb-ARF of the fluorescent type of dye laser or diode-end-pumped, although have very high pumping efficiency,, the former is bulky, only is suitable under lab carrying out determining and the usefulness of atom filter The Characteristic Study of physical parameter.The latter's problem is: a, domesticly there are not the semiconductor laser commodity of suitable Rb wavelength to obtain, and need be from foreign procurement; B, wavelength stabilized laser are relatively poor, impracticable (this point is proved to be in atomic frequency standard, and the atomic frequency standard of laser pump (ing) so far still fails to reach the practical stage).

3. the active thallium ARF of fluorescent type is for yarding up 6 ²P _3/2The atom metastable state has also used spectrum lamp to carry out pumping, but its operation wavelength and Rb-ARF are inequality, can not directly replace Rb-ARF, and, in order to satisfy the metastable condition of atom that produces, the thallium steam bubble can only keep low-down atomicity density, and therefore, output signal strength is restricted.

This shows that use traditional optical filter, the laser light communication system can only worked at night.In order to guarantee that laser light communication can carry out by day, then require to use more high efficiency filtering device.With interference filter (film, polarization etc.) compare with birefringent filter, ARF has big acceptance angle, narrower bandwidth and the characteristics such as optical filtering efficient of Geng Gao.Although present Rb-ARF makes that the laser light communication system by day also can operate as normal, because the commodity device that do not meet the demands can obtain, and the traditional design scheme is directly used in laser communication and still has problems such as huge, the impracticable or conversion efficiency of device is lower.

The purpose of this utility model just is to overcome problems of the prior art and deficiency, and research and build a kind of Rb-ARF of active, highly effective.

The purpose of this utility model is achieved in that

The utility model uses the Rb-ARF of electrodless discharge Rb spectrum lamp pumping.The use of Rb spectrum lamp in the Rb atomic frequency standard shown its practicality: the spectral purity height, radiation frequency is stable, volume is little, the life-span is long, the utility model is easy to and miscellaneous part makes up.For the Rb steam bubble, our size of main body of design is Φ 18 * 40mm, and the bubble tail of Φ a 5 * 50mm is arranged, and it guarantees that Rb steam conversion quantum efficiency is 28%.The optical maser wavelength of its wavelength and frequency multiplication Nd:YAG laser instrument (YAG crystal bar working temperature is 102 ℃) matches, but both couplings are one of selection schemes of Submarine Laser Communication.The utility model mainly is made up of electrodless discharge Rb spectrum lamp and atom steam bubble, and its principle of work is: at first allow electrodless discharge Rb spectrum lamp Rb D ₁Perhaps D ₂Linear light irradiation Rb steam bubble makes the Rb atom yard up 5 ²P _1/2Perhaps 5 ²P _3/2Excited state, Rb-ARF is in running order.When the incoming signal that matches with Rb atom highly excited level energy level spectral line during by the Rb steam bubble, excite S or D attitude behind the Rb atomic absorption signal photon from the 5P energy level transition to height, then, excited state Rb atomic radiation relaxation is got back to ground state through the nP attitude, by the atom internal conversion, comprise all information of signal in the atomic fluorescence of output.In extremely narrow atom live width, produce high permeability, and strong background noise is produced high the inhibition.Excite the transition of S attitude or D attitude from the 5P energy level to height, wherein making us interested especially is that operation wavelength is 532nm (5P _1/2-10S _1/2) Rb-ARF, its response time is a hundreds of ns magnitude, theoretical pure Rb atom steam bubble has a long mission life.Add the design of double furnace, duration of work can make the atomicity density constant of Rb steam bubble.In order to improve the detection sensitivity of Rb-ARF, we have used Rb steam to add molecule gas (H ₂Perhaps CO) mixing.

Advantage of the present utility model or good effect are:

1. owing to have the super-narrow line width light-filtering characteristic, make the laser light communication system can carry out operate as normal by day.

2. use electrodless discharge Rb spectrum lamp as pumping source, reduced the volume and weight of device, simplified the structure of device, make to the utlity model has practicality; 2. in atom resonance light filter (ARF) research, use the non-impurity-doped sample usually.We add convenient pressure H to bubble on the basis of studying atom and atom, the transfer of molecular collision energy ₂, CO gas, make the utility model under predetermined work temperature (130 ℃) 7 ²P5 ²S _1/2Fluorescence intensity ratio strengthens 6 respectively when using pure Rb to steep and (uses H ₂Gas) and 20 times (use CO gas), greatly improved the ARF detection sensitivity; Therefore, can increase the distance of laser light communication, perhaps increase the sea water advanced of Submarine Laser Communication.

Describe in detail below in conjunction with accompanying drawing and enforcement:

Fig. 1 is the utility model fundamental diagram.Wherein,

1-circuit box, promptly electrodless discharge Rb spectrum lamp exciting circuit box comprises semiconductor high frequency (98MHz) oscillatory circuit and heat radiator, its effect is to guarantee normal build-up of luminance of Rb bulb and steady operation;

2-muff, material is a polytetrafluoroethylplastic plastic, prevents that Rb bulb working temperature is with environmental temperature fluctuation;

3-red band pass filter only allows the 780mm of electrodless discharge Rb spectrum lamp and 794nm radiant light to pass through;

4-electrical heating wire, no magnetic double wrap, the electric energy that external dc power is provided becomes heat energy, and the Rb steam bubble is heated, and guarantees that Rb steam bubble wall does not have the Rb metal adhesion;

5-interference filter, the logical wavelength signals optical maser wavelength of its band matches;

6-optical glass window, its effect are temperature in the maintenance stove, prevent that hot-air from influencing the performance of interference filter, and allow pumping light, signal laser and atomic fluorescence to pass through on small loss ground as far as possible;

7-heating furnace is made by polytetrafluoroethylplastic plastic, in have electrical heating wire and temperature control, thermometric to use platinum wire resistance, can guarantee to be operated between the room temperature to 180 ℃ under arbitrary temperature, degree of stability is ± 0.3 ℃;

8-electrodeless Rb bulb comprises a few mgRb metals and inert gas, and encapsulation initial vacuum degree is better than 10 ^-5Torr;

9-oscillator coil, the part of electrodless discharge Rb spectrum lamp exciting circuit is made by Φ 2mm filamentary silver;

10-bogey, muff is made by polytetrafluoroethylplastic plastic, in electrical heating wire and temperature control, thermometric platinum wire resistance are arranged, be used to control the Rb vapour density, guarantee that at work the Rb steam in the Rb steam bubble is constant in a desired atomicity density;

11-Rb steam bubble, 95 glass are made, and are the cores of Rb-ARF, comprise Rb metal and molecular gas as actuating medium, at work, by adding thermosetting Rb atom vapor, charge into the interior vacuum tightness of Rb metal and molecular gas steam bubble before and are better than 10 ^-5Torr;

12-electrical heating wire, the constantan wire material, no magnetic double wrap is for bogey 10 provides thermal source;

13-blue light bandpass filter selects the atomic fluorescence of flashlight conversion to pass through, and matches with the operating wavelength range (420nm-311nm) of atomic fluorescence.

As shown in Figure 1, the utility model mainly is made up of electrodeless Rb bulb 8 and Rb steam bubble 11.Form electrodless discharge Rb spectrum lamp device by circuit box 1, muff 2, electrodeless Rb bulb 8 and oscillator coil 9.Circuit box 1 comprises high-frequency oscillating circuits and fin section; Muff 2 is fixed on the circuit box 1, and oscillator coil 9 is parts of oscillatory circuit, also is fixed on the circuit box; Oscillator coil 9 is positioned at muff 2; Electrodless discharge Rb bulb 8 is positioned in the middle of the oscillator coil 9, and its outer wall does not contact with oscillator coil 9, only is that the bubble tail is fixed on muff 2 rear walls; The front portion of muff 2 is equipped with red band pass filter 3, and is connected with heating furnace 7; Each port of heating furnace 7 all is equipped with optical glass sheet 6, is used to prevent the performance of heating furnace 7 temperature effect optical filters 3,5 and 13, and guarantees that the least possible loss flash of light preceding an earthquake passes through; Interference filter 5 is fixed on the heating furnace 7, and centre wavelength and incoming signal laser that its band is logical match, and the light of other wavelength is suppressed, and incoming signal laser is vertical mutually with pump light; Include electrical heating wire 4 in the heating furnace 7, reach thermometric, temperature control platinum resistance (not drawing), they guarantee that stove is operated under arbitrary definite temperature of room temperature-180 ℃ scope, and temperature-controlled precision is ± 0.3 ℃; Bogey 10 edge cover is installed on the heating furnace 7, also includes independently electrical heating wire 12, and thermometric, temperature control platinum resistance (not drawing) in the stove; During work, bogey 10 is by remaining on than low 10 ℃ of heating furnace 7 temperature; Rb steam bubble 11 is fixed on bogey 12 tops, and Rb steam bubble 11 main parts are positioned at heating furnace 7, during work, and no Rb metal adhesion on Rb steam bubble 11 walls; Rb steam bubble 11 afterbodys are positioned at bogey 10, contain the Rb metal of tens mg that have an appointment in the afterbody, guarantee that the Rb steam bubble has sufficiently long mission life.

By above analysis, the utility model is owing to ratio of performance to price height, and therefore highly effective has wide application prospect.

Claims (2)

1, a kind of active rubidium atom resonance light filter is characterized in that mainly being made up of electrodeless Rb bulb (8) and Rb steam bubble (11), and its annexation is:

1. form electrodless discharge Rb spectrum lamp device by circuit box (1), muff (2), electrodeless Rb bulb (8) and oscillator coil (9); Circuit box (1) comprises high-frequency oscillating circuits and fin section; Muff (2) is fixed on the circuit box (1), and oscillator coil (9) is the part of oscillatory circuit, also is fixed on the circuit box; Oscillator coil (9) is positioned at muff (2); Electrodeless Rb bulb (8) is positioned in the middle of the oscillator coil (9), and its outer wall does not contact with oscillator coil (9), only is that the bubble tail is fixed on muff (2) rear wall; The front portion of muff (2) is equipped with red band pass filter (3), and is connected with heating furnace (7); Each port of heating furnace (7) all is equipped with optical glass sheet (6); Interference filter (5) is fixed on the heating furnace (7), and centre wavelength and incoming signal laser that its band is logical match, and the light of other wavelength is suppressed, and makes incoming signal laser vertical mutually with pump light;

2. include electrical heating wire (4) in the heating furnace (7), reach thermometric, temperature control platinum resistance; Bogey (10) edge cover is installed on the heating furnace (7), also includes independently electrical heating wire (12), and thermometric, temperature control platinum resistance in the stove; Rb steam bubble (11) is fixed on bogey (12) top, and Rb steam bubble (11) main part is positioned at heating furnace (7); Rb steam bubble (11) afterbody is positioned at bogey (10), contains the Rb metal of tens mg that have an appointment in the afterbody.

2, swing light filter by the described a kind of active rubidium atom resonance of claim 1, it is characterized in that in Rb steam bubble (11), adding the H that convenient pressure is arranged ₂, CO gas.

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