WO2020181700A1

WO2020181700A1 - Saturated absorption spectrum frequency stabilized laser optical path, and saturated absorption spectrum frequency stabilized laser

Info

Publication number: WO2020181700A1
Application number: PCT/CN2019/096457
Authority: WO
Inventors: 张建伟
Original assignee: 清华大学
Priority date: 2019-03-11
Filing date: 2019-07-18
Publication date: 2020-09-17
Also published as: CN109755855B; CN109755855A

Abstract

The present application relates to a saturated absorption spectrum frequency stabilized laser optical path, and a saturated absorption spectrum frequency stabilized laser. The laser pumping is directed to the third reflective mirror after sequentially passing through the first reflective mirror, the second reflective mirror, the second polarizing beam splitter, and the gas chamber. After being reflected by the third reflective mirror, the laser pumping is output sequentially by the gas chamber, the fourth reflective mirror, and the first polarizing beam splitter. After being emitted from the first polarizing beam splitter, the detection light is sequentially directed to the third reflective mirror by means of the fourth reflective mirror and the gas chamber. After being reflected by the third reflective mirror, the detection light is directed to a detector by means of the gas chamber and the second polarizing beam splitter. An optical path of the laser pumping and that of the detection light in the gas chamber overlap with each other, and have the inverse direction. The length of the gas chamber can be reduced, and thus the volume and area occupied by the saturated absorption spectrum frequency stabilized laser optical path can be reduced for facilitating the use.

Description

Saturated absorption spectrum frequency stabilized laser optical path and saturated absorption spectrum frequency stabilized laser

Related application

This application claims the priority of the Chinese patent application filed on March 11, 2019, with application number 201910178551.X, titled "Optical Path of Saturated Absorption Spectrum Frequency Stabilized Laser and Saturated Absorption Spectrum Frequency Stabilized Laser", the full text of which is hereby Introduced as a reference.

Technical field

This application relates to the field of precision instruments, in particular to a saturated absorption spectrum frequency stabilized laser optical path and a saturated absorption spectrum frequency stabilized laser.

Background technique

High-performance, miniaturized and frequency-stabilized lasers have important applications in many basic scientific research, precision measurement, metrology and other fields. Saturated absorption spectrum frequency stabilization technology can lock the laser frequency to the specific transition spectrum line of atoms and molecules. It can not only ensure the long-term stability of the relative frequency of the locked laser output laser, but also realize the high absolute wavelength accuracy of the output laser. Therefore, the saturable absorption spectrum frequency-stabilized laser can be used in the fields of length reference, ultra-high precision length measurement and so on.

In practical applications of traditional high-performance frequency-stabilized lasers, in order to obtain higher spectral signal intensity, a longer gas cell is usually used in the optical path design of the laser, which results in a large optical path occupation area and volume. The problem of inconvenience.

Summary of the invention

Based on this, it is necessary to provide a saturated absorption spectrum frequency-stabilized laser optical path and a saturated absorption spectrum frequency-stabilized laser in response to the large volume and inconvenient use of traditional high-performance frequency stabilized lasers in practical applications.

An optical path of a saturable absorption spectrum frequency stabilized laser, including:

Base platform

The air chamber is arranged on the base platform;

The first polarizing beam splitter and the first reflecting mirror are arranged on the base platform at intervals along the direction in which the laser is incident, and both are located on one side of the air chamber. The first polarizing beam splitter is used to separate the The laser beam is divided into pump light and probe light, and the first reflector is used to reflect the pump light;

The second reflector and the second polarization beam splitter are arranged on the base platform at intervals and are arranged in sequence toward the laser entrance of the gas chamber;

The third reflecting mirror is arranged on the base platform and located at the laser outlet of the gas chamber;

A fourth reflecting mirror, arranged on the base platform, and located between the first polarization beam splitter and the second polarization beam splitter;

The pump light passes through the first reflector, the second reflector, the second polarization beam splitter, and the gas chamber in sequence, and is directed to the third reflector, and the pump light passes through After being reflected by the third mirror, the gas cell, the fourth mirror, and the first polarizing beam splitter are output in sequence;

After the probe light is emitted from the first polarizing beam splitter, it passes through the fourth reflector and the gas cell in turn to be directed toward the third reflector, and the probe light is reflected by the third reflector After passing through the gas chamber, the second polarization beam splitter is directed toward the detector, wherein the optical paths of the pump light and the probe light in the gas chamber overlap with opposite directions.

In an embodiment, it further includes:

The first half-wave plate is arranged on the side of the first polarization beam splitter away from the first reflector, and is used to adjust the pump light and the pump light directed to the first polarization beam splitter. The power ratio of the probe light.

In one embodiment, it further includes an optical isolator, which is arranged on a side of the first polarizing beam splitter away from the first reflector and used to isolate the reflected laser light.

In an embodiment, it further includes:

A first reflector adjustment frame, the first reflector is arranged on the first reflector adjustment frame;

In an embodiment, it further includes:

The second reflector adjustment frame, the second reflector is arranged on the second reflector adjustment frame.

In one embodiment, the optical path of the saturable absorption spectrum frequency stabilized laser is included.

In one embodiment, it further includes a laser transmitter, which is arranged on the base platform and is located on the side of the first polarization beam splitter away from the first reflector, and is used to split the beam to the first polarization The mirror emits the laser.

In one embodiment, it also includes

The detector is arranged on the base platform and located on the side of the second polarization beam splitter away from the first polarization beam splitter.

In one embodiment, the gas chamber is filled with iodine vapor.

In an embodiment, the laser transmitter is selected from a decentralized feedback semiconductor laser diode.

Base platform

The air chamber is arranged on the base platform;

The third polarization beam splitter, the first polarization beam splitter, and the first reflector are arranged on the base platform at intervals along the direction of laser injection, and they are all located on the same side of the gas chamber and directed toward the first The laser part of the three-polarization beam splitter is directed to the first polarization beam splitter through the third polarization beam splitter, and the laser beam is split into pump light and detected by the first polarization beam splitter. Light, part of the laser light is output from the third polarization beam splitter;

The pump light passes through the first reflector, the second reflector, the second polarizing beam splitter, and the air cell to the third reflector in sequence, and the pump light passes through the After being reflected by the third mirror, it passes through the air cell, the fourth mirror, the first polarization beam splitter, and outputs from the third polarization beam splitter;

The probe light is emitted from the first polarization beam splitter and then passes through the fourth reflector and the gas cell to the third reflector. After the probe light is reflected by the third reflector The detector is directed to the detector through the gas chamber and the second polarization beam splitter, wherein the optical paths of the pump light and the probe light in the gas chamber coincide.

In one embodiment, it further includes a first half-wave plate disposed between the first polarization beam splitter and the third polarization beam splitter.

In one embodiment, it further includes a second half-wave plate, which is arranged on the side of the third polarization beam splitter away from the first polarization beam splitter, and is used to adjust the pump light and the probe light Power ratio.

A saturated absorption spectrum frequency stabilized laser includes the optical path of the saturated absorption spectrum frequency stabilized laser.

In one embodiment, it further includes a laser transmitter, which is arranged on the base platform and is located on the side of the third polarization beam splitter away from the first reflector, and is used to split the beam to the first polarization The mirror emits the laser.

In an embodiment, it further includes:

In one embodiment, it further includes a connector, which is electrically connected to the laser transmitter, and is used to connect to a laser controller.

In one embodiment, the laser transmitter is a semiconductor laser diode.

In an embodiment, it further includes a detector circuit board, which is electrically connected to the detector.

In the optical path of the saturated absorption spectrum frequency-stabilized laser provided by the embodiment of the present application, the pump light sequentially passes through the first mirror, the second mirror, the second polarization beam splitter, and the gas chamber. To the third mirror, the pump light is reflected by the third mirror and then sequentially output through the air cell, the fourth mirror, and the first polarization beam splitter. The detection light passes through the fourth reflector and the gas cell in turn and is directed to the third reflector, and is reflected by the third reflector and then passes through the gas cell and the second polarization beam splitter. To the detector. That is, the pump light and the probe light both pass twice in the gas chamber. In addition, the optical paths of the pump light and the probe light in the gas chamber are the same, and the traveling directions are opposite. Therefore, the path length of the pump light and the probe light passing through the gas chamber is increased, thereby increasing the time and path length of the interaction between the pump light and the probe light and the gas in the gas chamber. Therefore, the optical path of the saturable absorption spectrum frequency-stabilized laser in this embodiment can reduce the length of the gas chamber without reducing the path length of the pump light and the probe light in the gas chamber. The volume and area occupied by the optical path of the saturated absorption spectrum frequency stabilized laser can be reduced, and it is convenient to use.

Description of the drawings

Figure 1 is a schematic diagram of the optical path of a saturated absorption spectrum frequency stabilized laser provided by an embodiment of the application;

Figure 2 is a schematic diagram of a saturated absorption spectrum frequency stabilized laser provided by an embodiment of the application;

3 is a schematic diagram of the optical path of a saturated absorption spectrum frequency stabilized laser provided by another embodiment of the application;

Figure 4 is a schematic diagram of a saturated absorption spectrum frequency stabilized laser provided by another embodiment of the application.

detailed description

In order to make the objectives, technical solutions, and advantages of the present application clearer, the following uses embodiments in conjunction with the drawings to further describe the saturated absorption spectrum frequency-stabilized laser and the saturated absorption spectrum frequency-stabilized laser of the present application in detail. It should be understood that the specific embodiments described herein are only used to explain the application, and not used to limit the application.

The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequence or technical meaning. The "connection" and "connection" mentioned in this application include direct and indirect connection (connection) unless otherwise specified. In the description of this application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", The orientation or positional relationship indicated by "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description , Rather than indicating or implying that the pointed device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the application.

In this application, unless expressly stipulated and defined otherwise, the “on” or “under” of the first feature on the second feature may be in direct contact with the first and second features, or indirectly through an intermediary. contact. Moreover, the "above", "above" and "above" of the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the level of the first feature is higher than the second feature. The “below”, “below” and “below” of the second feature of the first feature may mean that the first feature is directly below or obliquely below the second feature, or it simply means that the level of the first feature is smaller than the second feature.

Please refer to FIG. 1, an embodiment of the present application provides a saturable absorption spectrum frequency stabilized laser optical path 10. The optical path includes a base platform 100, an air chamber 110, a first polarization beam splitter 120, a first mirror 130, a second mirror 140, a second polarization beam splitter 150, a third mirror 160, and a fourth mirror 170. The air chamber 110 is disposed on the base platform 100. The first polarizing beam splitter 120 and the first reflecting mirror 130 are spaced apart on the base platform 100 along the direction in which the laser is incident, and both are located on one side of the gas chamber 110. The first polarization beam splitter 120 is used to split the laser beam into pump light and probe light, and the first mirror 130 is used to reflect the pump light. The second reflecting mirror 140 and the second polarizing beam splitter 150 are arranged on the base platform 100 at intervals, and are arranged in sequence toward the laser entrance 112 of the gas cell 110. The third reflector 160 is disposed on the base platform 100 and located at the laser outlet 114 of the gas chamber 110. The fourth reflecting mirror 170 is disposed on the base platform 100 and located between the first polarization beam splitter 120 and the second polarization beam splitter 150.

The pump light passes through the first reflector 130, the second reflector 140, the second polarizing beam splitter 150, and the air cell 110 in sequence, and is directed to the third reflector 160. The pump light is reflected by the third reflector 160 and then sequentially passes through the gas cell 110, the fourth reflector 170, and the first polarization beam splitter 120 to be output. After the detection light is emitted from the first polarization beam splitter 120, it passes through the fourth reflector 170 and the gas cell 110 and is directed toward the third reflector 160 in sequence. The probe light is reflected by the third reflector 160 and then passes through the gas cell 110 and the second polarizing beam splitter 150 to be directed toward the detector 240, wherein the pump light and the probe light are The light paths in the air chamber 110 coincide with opposite directions.

In the above-mentioned embodiment, the base platform 100 can be used as a supporting platform for light path components. The first polarization beam splitter 120 can divide the laser light into the pump light and the probe light. The probe light can be used for laser frequency locking. By changing the frequency of the laser light, the frequency of the probe light can be changed. Therefore, a saturated absorption spectrum signal can be obtained by switching the frequency of the probe light and conversion. At this time, the frequency of the laser light can be locked. At this time, the frequency of the pump light is the locked frequency, which can be used outside.

In this embodiment, the first linear optical path formed by the first polarizing beam splitter 120 and the first reflecting mirror 130, the second reflecting mirror 140 and the second polarizing beam splitter 150, the gas chamber 110, The second linear optical path formed by the third mirror 160 may be substantially parallel. The pump light may be emitted to the second linear optical path through the first linear optical path. Then, it is reflected by the third reflector 160 and then sequentially passes through the air cell 110, the fourth reflector 170, and the first polarization beam splitter 120 for output.

The detection light passes through the fourth reflector 170, the air cell 110 and is directed to the third reflector 160 in sequence, and is reflected by the third reflector 160 and then passes through the air cell 110, the second The polarization beam splitter 150 is directed toward the detector 240. That is, the pump light and the probe light both pass through the gas cell 110 twice. In addition, the optical paths of the pump light and the probe light in the gas cell 110 are the same, and the traveling directions are opposite. Therefore, the path length of the pump light and the probe light passing through the gas cell 110 is increased, thereby increasing the interaction time between the pump light and the probe light and the gas in the gas cell 110 And path length. Therefore, the saturable absorption spectrum frequency-stabilized laser light path 10 in this embodiment can reduce the length of the pump light and the probe light in the gas cell 110 without reducing the path length of the gas cell 110. In turn, the volume and area occupied by the optical path 10 of the saturated absorption spectrum frequency stabilized laser can be reduced, which is convenient for use.

In an embodiment, the saturated absorption spectrum frequency stabilized laser optical path 10 further includes a first half-wave plate 180. The first half-wave plate 180 is disposed on a side of the first polarization beam splitter 120 away from the first reflector 130. The first half-wave plate 180 is used to adjust the power ratio of the pump light and the probe light directed to the first polarization beam splitter 120.

In an embodiment, the optical path 10 of the saturated absorption spectrum frequency stabilized laser further includes an optical isolator 190. The optical isolator 190 is disposed on a side of the first polarization beam splitter 120 away from the first reflector 130. The optical isolator 190 is used to isolate the reflected laser light. The laser light passing through the optical isolator 190 is isolated by the optical isolator 190 and cannot return, so the laser can be protected.

In an embodiment, the optical path 10 of the saturated absorption spectrum frequency-stabilized laser further includes a first mirror adjustment frame 210 and a second mirror adjustment frame 220. The first mirror 130 is disposed on the first mirror adjusting frame 210. The second mirror 140 is disposed on the second mirror adjusting frame 220. The reflection direction of the first mirror 130 and the second mirror 140 to the laser can be adjusted by the first mirror adjustment frame 210 and the second mirror adjustment frame 220, respectively, and by adjusting the first mirror The mirror adjustment frame 210 and the second mirror adjustment frame 220 can make the paths of the pump light and the probe light in the gas chamber 110 coincide.

Referring to FIG. 2, an embodiment of the present application also provides a saturable absorption spectrum frequency stabilized laser 20. The saturated absorption spectrum frequency stabilized laser 20 includes the saturated absorption spectrum frequency stabilized laser optical path 10 in the foregoing embodiment. The saturated absorption spectrum frequency-stabilized laser 20 further includes a laser transmitter 230. The laser transmitter 230 is disposed on the base platform 100 and located on the side of the first polarization beam splitter 120 away from the first reflector 130. The laser transmitter 230 is used to emit the laser light to the first polarization beam splitter 120. The first polarization beam splitter 120 emitted by the laser transmitter 230 is divided into the pump light and the probe light.

In an embodiment, the saturated absorption spectrum frequency stabilized laser 20 further includes the detector 240. The detector 240 is disposed on the base platform 100 and located on the side of the second polarization beam splitter 150 away from the first polarization beam splitter 120. The detection light undergoes current-voltage conversion, amplification, and filtering in the detector 240 to obtain a saturated absorption spectrum signal, which can then be used for laser frequency locking.

In one embodiment, it further includes a detector circuit board 240, which is electrically connected to the detector 240.

In one embodiment, the gas chamber 110 is filled with iodine vapor. That is, the saturated absorption spectrum frequency stabilized laser 20 may be an iodine molecular spectrum frequency stabilized laser. The frequency stabilization performance of the saturated absorption spectrum depends on the signal-to-noise ratio of the saturated absorption spectrum signal. The size of the signal is related to the transition rate of molecules or atoms, the number of molecules or atoms participating in the interaction, and the laser intensity. Generally, the faster the transition rate of molecules or atoms, the stronger the signal, but the wider the signal spectrum; the more particles involved in the interaction, the stronger the signal. Heating the gas cell 110 can increase the particle number density, but it will cause The spectral line collision broadens and collision frequency shift; the laser intensity increases, the signal also increases, but after the laser intensity reaches the saturation light intensity, the signal is no longer significantly enhanced, but the spectral line will have a significant power broadening. For alkali metals with relatively high saturated vapor pressure at room temperature, it is easier to obtain a strong saturated absorption spectrum signal. However, for the spectrum of iodine molecules, due to the relatively weak line signal, a longer absorption bubble and higher laser power are usually used to obtain satisfactory signal intensity.

The inventor found that the current 633nm iodine molecular spectrum frequency-stabilized laser has defects such as large volume and low output power. Traditional 633nm iodine molecular spectrum frequency-stabilized laser adopts He-Ne laser, which is relatively large, and the output power of this type of laser is relatively low, usually less than 1mW. The length of the iodine molecular gas chamber 110 used for frequency stabilization is relatively long, usually tens of centimeters. In this embodiment, since the length of the gas cell 110 in the optical path 10 of the saturated absorption spectrum frequency-stabilized laser is relatively short, and does not affect the length of the optical path, the length of the gas cell 110 can be shortened under the premise of obtaining effective saturation absorption signal strength. , Thereby reducing the volume of the iodine molecular spectrum frequency stabilized laser.

In one embodiment, the laser transmitter 230 is selected from a distributed feedback semiconductor laser diode. When the saturated absorption spectrum frequency-stabilized laser is a 633nm DFB semiconductor laser with a frequency-stabilized iodine molecular spectrum, a 633nm butterfly packaged DFB semiconductor laser diode can be used with an output power of <10mW.

In this embodiment, the length of the gas cell 110 filled with iodine molecules is about 70 mm, and the laser is folded twice to pass through the gas cell 110, so that the interaction length between the laser and the iodine molecules is increased to about 140 mm. The output power of the DFB semiconductor laser is relatively low, and the detection light power can be adjusted to about 100 μW, and most of the laser light output by the DFB semiconductor laser is used as pump light, thereby increasing the saturation absorption signal intensity. Therefore, the laser light output by the DFB semiconductor laser can be fully utilized, and the final output power of the DFB semiconductor laser can be guaranteed, and the output power is greater than 5 mW. In this embodiment, the overall size of the laser head is about 150mm×95mm×45mm, and its volume is much smaller than that of the traditional iodine frequency stabilized HeNe laser. The use of a smaller volume mirror adjustment frame, a smaller packaged semiconductor laser, and a shorter gas chamber 110 can further reduce the size of the laser head.

In an embodiment, the gas chamber 110 may also be filled with alkali metal gas, and a semiconductor laser or other types of lasers can be applied through the alkali metal spectrum.

3, an embodiment of the present application also provides a saturated absorption spectrum frequency stabilized laser optical path 30. The saturated absorption spectrum frequency stabilized laser optical path 30 includes a base platform 100, an air cell 110, a third polarization beam splitter 250, and a third polarization beam splitter. A polarization beam splitter 120, a first mirror 130, a second mirror 140, a second polarization beam splitter 150, a third mirror 160, and a fourth mirror 170. The air chamber 110 is disposed on the base platform 100. The third polarization beam splitter 250, the first polarization beam splitter 120, and the first reflector 130 are spaced apart on the base platform 100 along the direction in which the laser is incident, and are all located in the air chamber 110 on the same side. The laser light directed to the third polarization beam splitter 120 is directed to the first polarization beam splitter 120 through the third polarization beam splitter 250, and the first polarization beam splitter 120 transmits the The laser beam is divided into pump light and probe light. Part of the laser light is output from the third polarizing beam splitter 250. The second reflecting mirror 140 and the second polarizing beam splitter 150 are spaced apart on the base platform 100 and face the laser entrance 112 of the gas cell 110. The directions are set in sequence. The third reflector 160 is disposed on the base platform 100 and located at the laser outlet 114 of the gas chamber 110. The fourth reflecting mirror 170 is disposed on the base platform 100 and located between the first polarization beam splitter 120 and the second polarization beam splitter 150.

The pump light passes through the first reflector 130, the second reflector 140, the second polarizing beam splitter 150, and the air cell 110 in turn to be directed toward the third reflector 160, After the pump light is reflected by the third mirror 160, it passes through the air cell 110, the fourth mirror 170, the first polarization beam splitter 120, and is output from the third polarization beam splitter 250 . The probe light is emitted from the first polarizing beam splitter 120 and then passes through the fourth reflector 170 and the air cell 110 to the third reflector 160 in sequence, and the probe light passes through the third reflector 160. The reflector 160 is reflected by the gas cell 110 and the second polarization beam splitter 150 to be directed toward the detector 240, wherein the optical paths of the pump light and the probe light in the gas cell 110 coincide.

In this embodiment, the third polarizing beam splitter 250 is used as the output end of the laser, and can be linearly moved on the side of the first polarizing beam splitter 120 away from the first reflecting mirror 130 as required, and then The output position of the pump light can be changed, and it is also convenient to adjust the angle of the output laser light. When the laser light is strong, before the laser light enters the first polarization beam splitter 120, part of the laser light may be output through the third polarization beam splitter 250 first.

The optical path 30 of the saturated absorption spectrum frequency stabilized laser in this embodiment has the advantages of the optical path of the saturated absorption spectrum frequency stabilized laser in the foregoing embodiment, which will not be repeated here.

In an embodiment, the optical path 30 of the saturated absorption spectrum frequency stabilized laser further includes a first half-wave plate 180. The first half-wave plate 180 is disposed between the first polarization beam splitter 120 and the third polarization beam splitter 250. The first half-wave plate 180 can be used to adjust the power ratio of the pump light and the probe light directed to the first polarization beam splitter 120.

In one embodiment, the saturated absorption spectrum frequency stabilized laser optical path 30 further includes a second half-wave plate 260, and the second half-wave plate 260 is arranged on the third polarization beam splitter 250 away from the first polarization beam splitter. One side of the beam splitter 120 is used to adjust the power ratio of the pump light and the probe light.

The second half-wave plate 260 can split the laser into two beams, and one beam is output to the outside through the third polarization beam splitter 250 for external use. The other beam is directed to the first polarization beam splitter 120. The second half-wave plate 260 may be used to adjust the ratio of the laser power output to the outside through the third polarization beam splitter 250 and the power of the laser light directed to the first polarization beam splitter 120.

Referring to FIG. 4, an embodiment of the present application also provides a saturable absorption spectrum frequency stabilized laser 40. The saturated absorption spectrum frequency-stabilized laser 40 includes the saturated absorption spectrum frequency-stabilized laser optical path 30, and also includes a laser transmitter 230, which is arranged on the base platform 100 and is located far away from the third polarization beam splitter 250. One side of the first reflecting mirror 130 is used to emit the laser light to the first polarization beam splitter 120. The saturated absorption spectrum frequency stabilized laser 40 has the advantages of the saturated absorption spectrum frequency stabilized laser in the foregoing embodiment. The volume of the saturated absorption spectrum frequency stabilized laser 40 can be significantly reduced. It can be understood that the third polarization beam splitter 250 can change the position of the laser output. The saturated absorption spectrum frequency-stabilized laser 40 can not only improve the detection efficiency of the saturated absorption spectrum of the limited power output laser, but also ensure the final output power of the laser. The saturated absorption spectrum frequency stabilized laser can be used for iodine molecular spectrum, alkali metal spectrum frequency stabilized semiconductor laser, Nd-YAG laser or He-Ne laser, etc.

In an embodiment, the saturated absorption spectrum frequency stabilized laser 40 further includes the detector 240. The detector 240 is disposed on the base platform 100 and located on the side of the second polarization beam splitter 150 away from the first polarization beam splitter 120.

In an embodiment, the saturated absorption spectrum frequency stabilized laser 40 further includes a connector 280. The connector 280 is electrically connected to the laser transmitter 230 for connecting to a laser controller. The laser controller can control the laser transmitter 230 through the connector 280. When the laser transmitter 230 is a semiconductor laser diode, the laser controller can control the temperature and current of the semiconductor laser diode through the connector 280, and use the saturated absorption spectrum signal detected by the detector 240 to After the current-voltage conversion and filtering and amplification are completed on the detector circuit board 270, the current and temperature of the laser diode are feedback-controlled, so as to control the output laser frequency of the laser diode, that is, frequency stabilization.

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, All should be considered as the scope of this specification.

The above-mentioned embodiments only express several implementation manners of the present application, and their description is relatively specific and detailed, but they should not be interpreted as a limitation of the scope of the patent. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can be made, and these all fall within the protection scope of this application. Therefore, the scope of protection of the patent of this application shall be subject to the appended claims.

Claims

An optical path of a saturable absorption spectrum frequency stabilized laser, which is characterized in that it comprises:

Base platform

The air chamber is arranged on the base platform;

The first polarizing beam splitter and the first reflecting mirror are arranged on the base platform at intervals along the direction in which the laser is incident, and both are located on one side of the air chamber. The first polarizing beam splitter is used to separate the The laser beam is divided into pump light and probe light, and the first reflector is used to reflect the pump light;

The second reflector and the second polarization beam splitter are arranged on the base platform at intervals and are arranged in sequence toward the laser entrance of the gas chamber;

The third reflecting mirror is arranged on the base platform and located at the laser outlet of the gas chamber;

A fourth reflecting mirror, arranged on the base platform, and located between the first polarization beam splitter and the second polarization beam splitter;

The pump light passes through the first reflector, the second reflector, the second polarization beam splitter, and the gas chamber in sequence, and is directed to the third reflector, and the pump light passes through After being reflected by the third mirror, the gas cell, the fourth mirror, and the first polarizing beam splitter are output in sequence;

After the probe light is emitted from the first polarizing beam splitter, it passes through the fourth reflector and the gas cell in turn to be directed toward the third reflector, and the probe light is reflected by the third reflector After passing through the gas chamber, the second polarization beam splitter is directed toward the detector, wherein the optical paths of the pump light and the probe light in the gas chamber overlap with opposite directions.
The optical path of the saturable absorption spectrum frequency-stabilized laser of claim 1, further comprising:

The first half-wave plate is arranged on the side of the first polarization beam splitter away from the first reflector, and is used to adjust the pump light and the pump light directed to the first polarization beam splitter. The power ratio of the probe light.
The optical path of the saturable absorption spectrum frequency-stabilized laser according to claim 1, further comprising an optical isolator, which is arranged on the side of the first polarization beam splitter away from the first reflector for isolating the The laser reflected light.
The optical path of the saturable absorption spectrum frequency-stabilized laser of claim 1, further comprising:

A first reflector adjustment frame, the first reflector is arranged on the first reflector adjustment frame;
The optical path of the saturable absorption spectrum frequency-stabilized laser according to claim 4, further comprising:

The second reflector adjustment frame, the second reflector is arranged on the second reflector adjustment frame.
A frequency-stabilized laser with saturated absorption spectrum, characterized by comprising the optical path of the frequency-stabilized saturated absorption spectrum laser according to any one of claims 1-4.
The saturable absorption spectrum frequency-stabilized laser according to claim 6, further comprising a laser transmitter, which is arranged on the base platform and located on the side of the first polarization beam splitter away from the first reflector, for The laser light is emitted to the first polarization beam splitter.
The saturable absorption spectrum frequency stabilized laser according to claim 6, characterized in that it further comprises

The detector is arranged on the base platform and located on the side of the second polarization beam splitter away from the first polarization beam splitter.
The saturable absorption spectrum frequency-stabilized laser of claim 6, wherein the gas chamber is filled with iodine vapor.
7. The saturable absorption spectrum frequency stabilized laser according to claim 6, wherein the laser transmitter is selected from a distributed feedback semiconductor laser diode.
An optical path of a saturable absorption spectrum frequency stabilized laser, which is characterized in that it comprises:

Base platform

The air chamber is arranged on the base platform;

The third polarization beam splitter, the first polarization beam splitter, and the first reflector are arranged on the base platform at intervals along the direction of laser injection, and they are all located on the same side of the gas chamber and directed toward the first The laser part of the three-polarization beam splitter is directed to the first polarization beam splitter through the third polarization beam splitter, and the laser beam is split into pump light and detected by the first polarization beam splitter. Light, part of the laser light is output from the third polarization beam splitter;

The second reflector and the second polarization beam splitter are arranged on the base platform at intervals and are arranged in sequence toward the laser entrance of the gas chamber;

The third reflecting mirror is arranged on the base platform and located at the laser outlet of the gas chamber;

A fourth reflecting mirror, arranged on the base platform, and located between the first polarization beam splitter and the second polarization beam splitter;

The pump light passes through the first reflector, the second reflector, the second polarizing beam splitter, and the air cell to the third reflector in sequence, and the pump light passes through the After being reflected by the third mirror, it passes through the air cell, the fourth mirror, the first polarization beam splitter, and outputs from the third polarization beam splitter;

The probe light is emitted from the first polarization beam splitter and then passes through the fourth reflector and the gas cell to the third reflector. After the probe light is reflected by the third reflector The detector is directed to the detector through the gas chamber and the second polarization beam splitter, wherein the optical paths of the pump light and the probe light in the gas chamber coincide.
8. The optical path of the saturable absorption spectrum frequency-stabilized laser according to claim 11, further comprising a first half-wave plate disposed between the first polarization beam splitter and the third polarization beam splitter.
The optical path of the saturable absorption spectrum frequency-stabilized laser according to claim 12, further comprising a second half-wave plate arranged on the side of the third polarization beam splitter away from the first polarization beam splitter, It is used to adjust the power ratio of the pump light and the probe light.
A frequency-stabilized laser with saturated absorption spectrum, characterized by comprising the optical path of the frequency-stabilized saturated absorption spectrum laser according to any one of claims 11-13.
The saturable absorption spectrum frequency-stabilized laser according to claim 14, further comprising a laser transmitter, which is arranged on the base platform and is located on a side of the third polarization beam splitter away from the first reflector. Side, for emitting the laser light to the first polarization beam splitter.
The saturable absorption spectrum frequency stabilized laser according to claim 14, characterized in that it further comprises:

The detector is arranged on the base platform and located on the side of the second polarization beam splitter away from the first polarization beam splitter.
The saturable absorption spectrum frequency-stabilized laser according to claim 14, further comprising a connector, which is electrically connected to the laser transmitter, for connecting to a laser controller.
The saturable absorption spectrum frequency stabilized laser of claim 17, wherein the laser transmitter is a semiconductor laser diode.
The saturable absorption spectrum frequency stabilized laser of claim 16, further comprising a detector circuit board, which is electrically connected to the detector.