阅读说明：本技术 一种高真空低温环境下的光学斩波器 (A kind of optical chopper under high vacuum low temperature environment ) 是由 刘玉芳 李龙飞 于坤 张凯华 赵保林 于 2019-08-29 设计创作，主要内容包括：本发明公开了一种高真空低温环境下的光学斩波器,包括低温斩波片、腔内转轴、双轴输出伺服电机、腔外转轴、常温斩波片、U型光电开关和控制器,经过通光孔的弱辐射光信号被均匀地调制成交变的辐射光信号,此时通过固定在常温斩波片周边的U型光电开关实时读取出常温斩波片的转动频率即低温斩波片的转动频率,并输入控制器转化成能够被锁相放大器识别的交变参考电信号,从而使锁相放大器完成对待测目标辐射信号的识别和放大。本发明可以在高真空低温环境下将微弱的辐射光信号调制为频率已知的交变的辐射光信号,从而进行识别和放大。(The invention discloses the optical choppers under a kind of high vacuum low temperature environment, including low temperature copped wave piece, intracavitary shaft, twin shaft exports servo motor, chamber outer shaft, room temperature copped wave piece, U-shaped optoelectronic switch and controller, the radiation optical signal of alternation is equably modulated by the weak radiation optical signal of light hole, read out the rotational frequency i.e. rotational frequency of low temperature copped wave piece of room temperature copped wave piece in real time by being fixed on the U-shaped optoelectronic switch on room temperature copped wave piece periphery at this time, and input controller is converted to the alternation reference electrical signal that can be phase locked amplifier identification, to make lock-in amplifier complete identification and amplification to target emanation signal to be measured.Faint radiation optical signal modulation can be the radiation optical signal of alternation known to frequency under high vacuum low temperature environment by the present invention, to be identified and be amplified.)

1. the optical chopper under a kind of high vacuum low temperature environment, it is characterised in that including low temperature copped wave piece, intracavitary shaft, twin shaft Servo motor, chamber outer shaft, room temperature copped wave piece, U-shaped optoelectronic switch and controller are exported, wherein low temperature copped wave piece is in vacuum chamber Interior, the low temperature copped wave piece and shaft in the output shaft transit chamber of servo motor side are coaxially connected, and low temperature copped wave piece is installed on two The inside being oppositely arranged is furnished between the refrigeration shell of liquid nitrogen pipes, passes through hot spoke between two refrigeration shells and low temperature copped wave piece It penetrates and reaches thermal equilibrium state, to realize the cooling to low temperature copped wave piece, the refrigeration shell being oppositely arranged is equipped with light hole, passes through Low temperature copped wave piece of the faint radiation optical signal through rotating of refrigeration shell light hole is equably modulated into the radiant light letter of alternation Number；Servo motor, room temperature copped wave piece and U-shaped optoelectronic switch are in outside vacuum chamber, and the room temperature copped wave piece and servo motor are another Side output shaft transit chamber outer shaft is coaxially connected, and room temperature copped wave piece periphery, which is equipped with, is used for real-time monitoring room temperature copped wave piece rotational frequency U-shaped optoelectronic switch, since low temperature copped wave piece and room temperature copped wave piece are coaxially connected, therefore low temperature copped wave piece has with room temperature copped wave piece Identical rotational frequency passes through the rotational frequency input controller of the low temperature copped wave piece for acquiring U-shaped optoelectronic switch and is converted to It can be phase locked the alternation reference electrical signal of amplifier identification, so that lock-in amplifier is completed to target emanation signal to be measured Identification and amplification.

2. the optical chopper under high vacuum low temperature environment according to claim 1, it is characterised in that: the servo motor Revolving speed can reach 3000r/s.

3. the optical chopper under high vacuum low temperature environment according to claim 1, it is characterised in that: the intracavitary shaft Pass through magnet fluid sealing with the junction of high vacuum chamber.

4. the optical chopper under high vacuum low temperature environment according to claim 1, it is characterised in that: the low temperature copped wave Piece is coaxially connected with room temperature copped wave piece and structure is consistent, and thickness is 1mm, the opposite side of two refrigeration shells be respectively equipped with The depth that low temperature copped wave piece matches is the circular groove of 1.5mm, and low temperature copped wave piece is set to two refrigeration shells with respect to fastening group It fills in the cylinder cavity with a thickness of 3mm formed to realize that low temperature copped wave piece is freely rotated in cylinder cavity, the low temperature The temperature of copped wave piece is lower than -100 DEG C.

5. the optical chopper under high vacuum low temperature environment according to claim 1, it is characterised in that: the refrigeration shell On be provided with diameter be 25mm light hole, refrigeration shell and low temperature copped wave on piece are coated with the pitch-dark of high emissivity, are used for Increase the heat radiation between refrigeration shell and low temperature copped wave piece and does not increase the influence of stray light.

Technical field

The invention belongs to low temperature and signal modulation technique fields, and in particular to the optics under a kind of high vacuum low temperature environment is cut Wave device.

Background technique

In the radiation characteristic with direct method measurement material, especially measurement low-temp radiating characteristic, due to material itself Heat radiation energy is weaker, and usual measuring signal is easy to be submerged in noise signal, leads to not obtain authentic and valid survey Magnitude.Laboratory generally will radiate weak signal from noise signal using chopper and lock-in amplifier in measurement process at present It extracts, and does enhanced processing.This method is widely used in the material Radiation biodosimetry of room temperature and high temperature, however In the lower measurement process of temperature, if chopper is not under low temperature environment, the temperature of copped wave piece is justMeetingThan to measure Target it is taller, copped wave piece inherently becomes a direct hot interference source at this time, can seriously affect the survey of target emanation Accuracy of measurement.Want influence of the heat radiation of reduction copped wave piece itself to measuring signal, there are two types of methods at present: 1, reducing as far as possible The emissivity of copped wave piece；2, the temperature for reducing copped wave piece, makes it largely be lower than the temperature of object to be measured.The first side Method realization is relatively simple, but the emissivity for reducing copped wave piece means that and increases its reflectivity, and the increase of reflectivity will increase The influence of stray light increases multiple interference sources for being difficult to assess for measuring system.Second method can theoretically solve well Certainly the problem of low-temp radiating signal measurement, but it also can not find the optics copped wave that can be suitable for high vacuum low temperature currently on the market Device, while can not find and the private of high-speed cruising can take motor under high vacuum low temperature environment, the copped wave tune under low temperature can not be built System processed.

Summary of the invention

The present invention proposes high vacuum that is a kind of low in cost and being easily achieved on the basis of low-temp radiating measurement demand Optical chopper under low temperature environment.

The present invention adopts the following technical scheme that solve above-mentioned technical problem, and the optics under a kind of high vacuum low temperature environment is cut Wave device, it is characterised in that export servo motor, chamber outer shaft, room temperature copped wave piece, U including low temperature copped wave piece, intracavitary shaft, twin shaft Type optoelectronic switch and controller, wherein low temperature copped wave piece is in vacuum chamber, and the low temperature copped wave piece and servo motor side export Shaft is coaxially connected in axis transit chamber, and low temperature copped wave piece is installed on the inside that two are oppositely arranged and is furnished with outside the refrigeration of liquid nitrogen pipes Between shell, thermal equilibrium state is reached by heat radiation between two refrigeration shells and low temperature copped wave piece, to realize to low temperature copped wave The cooling of piece, the refrigeration shell being oppositely arranged are equipped with light hole, are passed through by the faint radiation optical signal of refrigeration shell light hole The low temperature copped wave piece of rotation is equably modulated into the radiation optical signal of alternation；Servo motor, room temperature copped wave piece and U-shaped photoelectricity are opened Pass is in outside vacuum chamber, and the room temperature copped wave piece and servo motor other side output shaft transit chamber outer shaft are coaxially connected, room temperature Copped wave piece periphery is equipped with the U-shaped optoelectronic switch for real-time monitoring room temperature copped wave piece rotational frequency, due to low temperature copped wave piece and often Warm copped wave piece is coaxially connected, therefore low temperature copped wave piece and room temperature copped wave piece rotational frequency having the same, by by U-shaped optoelectronic switch The rotational frequency input controller of the low temperature copped wave piece of acquisition is simultaneously converted to the alternation that can be phase locked amplifier identification with reference to electricity Signal, so that lock-in amplifier completes the identification and amplification to target emanation signal to be measured.

Further preferably, the revolving speed of the servo motor can reach 3000r/s.

Further preferably, the junction of the intracavitary shaft and high vacuum chamber passes through magnet fluid sealing.

Further preferably, the low temperature copped wave piece is coaxially connected with room temperature copped wave piece and structure is consistent, and thickness is 1mm, the opposite side of two refrigeration shells are respectively equipped with the circular groove that the depth to match with low temperature copped wave piece is 1.5mm, low temperature Copped wave piece is set in the opposite cylinder cavity with a thickness of 3mm for fastening assembling formation of two refrigeration shells to realize that low temperature is cut Wave plate is freely rotated in cylinder cavity, and the temperature of the low temperature copped wave piece is lower than -100 DEG C.

Further preferably, the light hole that diameter is 25mm, refrigeration shell and low temperature copped wave are provided in the refrigeration shell On piece is coated with the pitch-dark of high emissivity, for increasing the heat radiation between refrigeration shell and low temperature copped wave piece and not increasing miscellaneous The influence of astigmatism.

The advantage that the prior art of the present invention is compared is:

1, the optical chopper under high vacuum low temperature environment proposed by the present invention can will be faint under high vacuum low temperature environment The radiation optical signal that optical signal modulation is alternation known to frequency is radiated, to be identified and be amplified.

2, the optical chopper under high vacuum low temperature environment proposed by the present invention is while modulated optical signal, low temperature copped wave Piece temperature is significantly lower than target temperature, and all sprays high emissivity coating around low temperature copped wave piece and refrigeration shell, so The influence of stray light is not increased.

3, and real-time monitoring coaxially connected using two identical low temperature copped wave pieces and room temperature copped wave piece of the invention, solution The problem of monitoring chopping frequency is difficult under high vacuum of having determined low temperature environment.

4, the twin shaft output servo motor that the present invention uses, which is placed under normal temperature and pressure environment, to be run, and servo motor is not needed Reach exacting terms, it is easy to accomplish and cost is relatively low.

Detailed description of the invention

Fig. 1 is structural schematic diagram of the invention；

Fig. 2 is the assembling exploded view of low temperature copped wave piece and refrigeration shell in the present invention；

Fig. 3 is low temperature copped wave piece and the structural schematic diagram after refrigeration shell assembling in the present invention.

In figure: 1- low temperature copped wave piece；The intracavitary shaft of 2-；3- servo motor；4- chamber outer shaft；5- room temperature copped wave piece；6-U type Optoelectronic switch；7- controller, 8- refrigeration shell, 9- light hole, 10- vacuum chamber.

Specific embodiment

In conjunction with attached drawing, the technical schemes of the invention are described in detail, as shown in Figure 1, high vacuum low temperature environment proposed by the present invention Under optical chopper specifically include low temperature copped wave piece 1, intracavitary shaft 2, twin shaft output servo motor 3, chamber outer shaft 4, room temperature Copped wave piece 5, U-shaped optoelectronic switch 6 and controller 7, the optical chopper under the high vacuum low temperature environment can be in high vacuum chamber 10 Interior normal work, and 1 temperature of low temperature copped wave piece is lower than -100 DEG C；What the optical chopper under the high vacuum low temperature environment used Servo motor 3 is arranged outside high vacuum chamber 10, and revolving speed can reach 3000r/s；Optics under the high vacuum low temperature environment For chopper tool there are two the identical copped wave piece of coaxially connected and structure, one is low temperature copped wave piece 1 in high vacuum low temperature environment, The low temperature copped wave piece 1 and shaft 2 in 3 side output shaft transit chamber of servo motor are coaxially connected, another is in normal temperature and pressure ring Border is room temperature copped wave piece 5, and the room temperature copped wave piece 5 and 3 other side output shaft transit chamber outer shaft 4 of servo motor are coaxially connected；Institute It states intracavitary shaft 2 and the junction of high vacuum chamber 10 passes through magnet fluid sealing；The low temperature copped wave piece 1 is mounted on two and sets relatively The inside set is furnished among the refrigeration shell 8 of liquid nitrogen pipes, low temperature copped wave piece 1 with a thickness of 1mm, two refrigeration being oppositely arranged The circular groove that the opposite side of shell 8 is equipped with a depth 1.5mm and matches with low temperature copped wave piece 1, low temperature copped wave piece 1 can be two A opposite fasten of refrigeration shell 8 is freely rotated in the cylindrical cavity with a thickness of 3mm that assembling is formed；Outside the refrigeration being oppositely arranged The light hole 9 of diameter 25mm is offered on shell 8, is coated with the black of high emissivity on refrigeration shell 8 and low temperature copped wave piece 1 Paint, does not increase the influence of stray light for increasing the heat radiation between refrigeration shell 8 and low temperature copped wave piece 1 simultaneously；Two opposite Thermal equilibrium state is finally reached by heat radiation between the refrigeration shell 8 and low temperature copped wave piece 1 of setting, and then realizes low temperature copped wave The cooling of piece 1, simultaneously because low temperature copped wave piece 1 is in high-speed rotation, although light hole 9 can influence low temperature copped wave to a certain extent 1 temperature level of piece, but not destroy its temperature uniformity；The low temperature copped wave piece 1 and room temperature copped wave piece 5 is coaxially connected and structure Unanimously, since low temperature copped wave piece 1 and room temperature copped wave piece 5 are in axial installation site having the same, therefore low temperature copped wave piece 1 and room temperature The rotational frequency having the same of copped wave piece 5 and phase；5 periphery of room temperature copped wave piece, which is equipped with, is used for real-time monitoring room temperature copped wave piece The U-shaped optoelectronic switch 6 of 5 rotational frequencies, since low temperature copped wave piece 1 and room temperature copped wave piece 5 are coaxially connected, therefore low temperature copped wave piece 1 with Room temperature copped wave piece 5 rotational frequency and phase having the same, pass through the rotation for the low temperature copped wave piece 1 for acquiring U-shaped optoelectronic switch 6 Frequency input controller 7 is simultaneously converted to the alternation reference electrical signal that can be phase locked amplifier identification, so that locking phase is amplified Device completes the identification and amplification to target emanation signal to be measured.

Several important components are described further with reference to the accompanying drawing；As depicted in figs. 1 and 2, the Gao Zhen It is intracavitary that the low temperature copped wave piece of optical chopper under empty low temperature environment and its refrigeration shell of two sides are in high vacuum, and servo Motor, room temperature copped wave piece and U-shaped optoelectronic switch are in outside high vacuum chamber, wherein low temperature copped wave piece and the output of servo motor side Axis is coaxially connected using intracavitary shaft, and room temperature copped wave piece and servo motor other side output shaft transit chamber outer shaft are coaxially connected, Consistent with the rotational frequency of room temperature copped wave piece for realizing low temperature copped wave piece, the junction of intracavitary shaft and high vacuum chamber uses magnetic Fluid Sealing.

As shown in Figures 2 and 3, after each component of low temperature chopper installs, two refrigeration shells are intermediate after connecting It just can be for cylindrical cavity that low temperature copped wave piece is freely rotated there are one.In high vacuum environment, refrigeration shell with it is low It can only be exchanged heat by heat radiation between warm copped wave piece, firstly, opening servo motor, make low temperature copped wave piece according to predeterminated frequency High-speed rotation；Secondly, being passed through liquid nitrogen into the liquid nitrogen pipes of two refrigeration shell internal arrangements, cool down to refrigeration shell.Due to Low temperature copped wave piece high-speed rotation, low temperature copped wave piece equably carry out heat radiation cooling to refrigeration shell, at the same extraneous radiation across Light hole is irradiated to low temperature copped wave on piece, and low temperature copped wave piece can be made to heat up to a certain extent, after a period of time, low temperature Copped wave piece is finally reached thermal equilibrium state.Due to the bore very little of light hole, and low temperature copped wave piece is in high-speed rotation, external world's radiation Only increase by a small margin low temperature copped wave piece temperature, the temperature uniformity of ring low temperature copped wave piece will not be broken, together Deformation occurs because non-uniform temperature leads to copped wave plate plane by Shi Buhui.

After low temperature copped wave piece reaches thermal balance, struck a bargain by the faint radiation optical signal of light hole by equably modulation The radiation optical signal of change reads out room temperature copped wave piece by being fixed on the U-shaped optoelectronic switch on room temperature copped wave piece periphery at this time in real time Rotational frequency, that is, low temperature copped wave piece rotational frequency, and input controller be converted to can be phase locked amplifier identification alternation Reference electrical signal, so that lock-in amplifier be made to complete identification and amplification to target emanation signal to be measured.

Basic principle of the invention, main feature and advantage has been shown and described above, do not depart from spirit of that invention and Under the premise of range, there are also various changes and modifications, these changes and improvements to both fall within claimed invention by the present invention Range.