WO2021098184A1

WO2021098184A1 - Laser light deep compression method and laser

Info

Publication number: WO2021098184A1
Application number: PCT/CN2020/094349
Authority: WO
Inventors: 朱涛; 黄礼刚; 高磊; 尹国路
Original assignee: 重庆大学
Priority date: 2019-11-22
Filing date: 2020-06-04
Publication date: 2021-05-27

Abstract

Provided are a laser light linewidth deep compression method and an ultra-narrow linewidth laser. The compression method mainly comprises: a laser light generation gain unit (1) emitting laser light; the emitted laser light passing through a distributed scattering feedback unit, wherein part of the laser light is transmitted and output, and the remaining part is fed back to the laser light generation gain unit (1); the laser light generation gain unit (1) receiving the laser light that is fed back, and after performing gaining on the laser light, sending same to the distributed scattering feedback unit; and repeating the cycle until a laser light parameter reaches an equilibrium state, so that deep compression of the laser light is realized. The technical problem in the field of lasers of it not being possible to use a traditional fixed optical feedback manner to realize laser light linewidth deep compression while obtaining a mode selection is mainly solved, and the smaller volume, better stability and wider structure extensibility of the whole system of a laser are realized.

Description

一种激光深压缩方法及激光器Laser deep compression method and laser

技术领域Technical field

本发明属于激光技术领域，涉及一种激光深压缩方法及激光器。The invention belongs to the field of laser technology, and relates to a laser deep compression method and a laser.

背景技术Background technique

超窄线宽激光原始阵列具有多波长、长相干长度、高集成度和低相位噪声等特点，因此在激光雷达、数字相干传输***等应用领域中都有十分重要的应用前景。至今，对激光线宽特性的研究大部分集中在对波导光的一维传输过程中，少有对空间光线宽压缩的详细研究。以目前的对于空间光线宽压缩方法而言，如采用多镜面反射与耦合为波导光后再采用外腔法，目前的各类方法中都存在或是***庞大、或是需限定波长以及难以直接调控等缺点。因此如何实现在保证结构简单，成本低廉的前提下实现对空间光结构的激光线宽的深压缩是该领域当前所面临的一个难题。The original ultra-narrow linewidth laser array has the characteristics of multi-wavelength, long coherence length, high integration and low phase noise, so it has very important application prospects in applications such as lidar and digital coherent transmission systems. So far, most of the research on laser linewidth characteristics has focused on the one-dimensional transmission process of waveguide light, and there are few detailed studies on spatial light width compression. In terms of the current wide compression methods for spatial light, such as adopting multi-mirror reflection and coupling into waveguide light and then adopting the external cavity method, all of the current methods have large systems, or need to limit the wavelength, and are difficult to directly Disadvantages such as regulation. Therefore, how to realize the deep compression of the laser linewidth of the spatial light structure under the premise of ensuring a simple structure and low cost is a difficult problem currently faced by this field.

另一方面，输出波长具有可调谐特性的超窄线宽激光器不仅具有灵活的波长选择性和范围较大的波长可调特性，同时具有超长的相干长度和极低的相位噪声，因此具有灵敏度高、范围广等特点，在很多诸如相干探测、光分辨率光谱，精确传感及生物医疗等新兴领域内具有十分重要的应用前景(这些应用领域对于激光线宽的要求较高)。迄今，采用短腔结构和饱和吸收体方法是在实现波长可调谐的同时保证激光呈单纵模运转的常用方法。然而，这些传统的方法只是实现了激光的模式选择，并不能够在此基础上实现激光线宽的进一步压缩。因此如何在实现激光波长持续可调的同时获得激光线宽的深压缩是该领域当前所面临的一个难题。On the other hand, the ultra-narrow linewidth laser with tunable output wavelength not only has flexible wavelength selectivity and a wide range of wavelength tunable characteristics, but also has an ultra-long coherence length and extremely low phase noise, so it has sensitivity The characteristics of high and wide range have very important application prospects in many emerging fields such as coherent detection, optical resolution spectroscopy, precision sensing and biomedicine (these application fields have higher requirements for laser linewidth). So far, the short-cavity structure and saturable absorber method are commonly used methods to ensure that the laser is operated in a single longitudinal mode while achieving wavelength tunability. However, these traditional methods only realize the mode selection of the laser, and cannot achieve further compression of the laser linewidth on this basis. Therefore, how to achieve deep compression of the laser linewidth while achieving continuous adjustment of the laser wavelength is a difficult problem currently faced by this field.

并且，单纵模运转的超窄线宽激光器由于其超长的相干长度和极低的相位噪声在光纤传感、光纤通信、激光雷达及引力波探测等领域具有重要的应用前景。而激光的单纵模运转是实现激光线宽压缩的前提基础。迄今，除了包括采用短腔结构、饱和吸收体等的模式选择方法外，光学注入反馈已成为获得激光线宽窄化的常用方法。然而，传统的光注入反馈作为一种单路径的功率回馈，由于其引入的额外腔长将导致同等条件下自由光谱范围(FSR)的减小，难以实现激光的单纵模运转。同时，由于其仅仅是一种功率回馈，有限的回馈腔长将限制了其线宽的进一步压缩。另外，通过增加回馈腔长来实现激光线宽窄化的方式难以实现激光器的集成化和小型化。因此，寻找一种能够使得激光呈无纵模输出，并具有集成化潜能的激光线宽深压缩方法是当前超窄线宽激光器领域所面临的重要问题。Moreover, the ultra-narrow linewidth laser operating in single longitudinal mode has important application prospects in the fields of optical fiber sensing, optical fiber communication, lidar and gravitational wave detection due to its long coherence length and extremely low phase noise. The single-longitudinal mode operation of the laser is the prerequisite for the realization of laser linewidth compression. So far, in addition to mode selection methods including the use of short cavity structures, saturable absorbers, etc., optical injection feedback has become a common method for obtaining laser linewidth narrowing. However, the traditional optical injection feedback is a single-path power feedback, and the additional cavity length introduced by it will reduce the free spectral range (FSR) under the same conditions, making it difficult to achieve single longitudinal mode operation of the laser. At the same time, since it is only a kind of power feedback, the limited length of the feedback cavity will limit the further compression of its line width. In addition, it is difficult to realize the integration and miniaturization of the laser by increasing the length of the feedback cavity to achieve the narrowing of the laser line width. Therefore, looking for a laser linewidth deep compression method that can make the laser output without longitudinal mode and has the potential for integration is an important problem facing the field of ultra-narrow linewidth lasers.

发明内容Summary of the invention

本发明的目的在于提供一种激光深压缩方法及激光器。主要解决了激光器领域中采用传统光学反馈方式在获得模式选择的同时难以实现激光线宽深压缩的技术问题。The purpose of the present invention is to provide a laser deep compression method and laser. It mainly solves the technical problem that the traditional optical feedback method in the laser field is difficult to achieve deep compression of the laser linewidth while obtaining mode selection.

技术方案具体如下：The technical scheme is as follows:

本发明的技术方案之一是一种激光深压缩方法，包括以下步骤：One of the technical solutions of the present invention is a laser deep compression method, which includes the following steps:

1)激光发生增益单元发出激光信号；1) The laser generating gain unit sends out the laser signal;

2)发出的激光信号经过分布式散射回馈单元，所述激光信号的一部分输出，所述激光信号的其余部分回馈到激光发生增益单元；2) The emitted laser signal passes through the distributed scattering feedback unit, a part of the laser signal is output, and the rest of the laser signal is fed back to the laser generation gain unit;

3)所述激光发生增益单元接收到回馈的所述其余部分，对其进行增益后再次发出至所述分布式散射回馈单元。3) The laser generating gain unit receives the remaining part of the feedback, gains it, and sends it to the distributed scattering feedback unit again.

本发明的技术方案之二是一种激光器，包括激光发生增益单元、分布式散射回馈单元；The second technical solution of the present invention is a laser, including a laser generating gain unit and a distributed scattering feedback unit;

所述激光发生增益单元，用于产生初始激光信号，并对从所述分布式散射回馈单元接受的后向散射回馈信号进行增益放大，并将经所述增益放大后的所述后向散射回馈信号再次传输至所述分布式散射回馈单元。；The laser generating gain unit is configured to generate an initial laser signal, and perform gain amplification on the backscatter feedback signal received from the distributed scattering feedback unit, and feed back the backscattered feedback signal amplified by the gain The signal is again transmitted to the distributed scattering feedback unit. ；

所述分布式散射回馈单元，当所述初始激光信号经过时产生分布式散射回馈信号，并将所述分布式散射信号中的所述后向散射信号回馈到所述激光发生增益单元实现增益放大。。The distributed scattering feedback unit generates a distributed scattering feedback signal when the initial laser signal passes through, and feeds the backscattered signal in the distributed scattering signal back to the laser generating gain unit to achieve gain amplification . .

本发明中，一种激光器可以是基于空间光散射回馈结构的窄线宽激光器，In the present invention, a laser may be a narrow linewidth laser based on a spatial light scattering feedback structure,

还包括链接所述激光发射增益单元和所述分布式散射回馈单元的透镜结构；It also includes a lens structure linking the laser emission gain unit and the distributed scattering feedback unit;

所述透镜结构包括耦合透镜，半透半反镜片和凸透镜；The lens structure includes a coupling lens, a transflective lens and a convex lens;

所述激光发生增益单元包括常规光学腔与面上芯片等所有可形成激光的结构，且内部没有空间光隔离器，有利于接收后续的反馈信号；The laser-generating gain unit includes all structures that can form lasers, such as a conventional optical cavity and a chip-on-surface, and there is no spatial optical isolator inside, which is beneficial to receiving subsequent feedback signals;

所述分布式散射回馈单元包括散射增益介质与半球面镜，其中散射增益介质均匀分布在半球面镜内侧；The distributed scattering feedback unit includes a scattering gain medium and a hemispherical mirror, wherein the scattering gain medium is uniformly distributed inside the hemispherical mirror;

所述激光发生增益单元产生所述初始激光后输出到所述耦合透镜，所述初始激光经所述耦合透镜耦合后水平传输的空间光；The laser generating and gaining unit generates the initial laser light and outputs it to the coupling lens, and the initial laser light is coupled by the coupling lens and then horizontally transmitted spatial light;

所述空间光传输到所述半透半反镜片，并产生对应的透射光与反射光，其中透射光继续传输至所述凸透镜，反射光作为输出激光输出；The spatial light is transmitted to the semi-transmissive and semi-reflective lens to generate corresponding transmitted light and reflected light, wherein the transmitted light continues to be transmitted to the convex lens, and the reflected light is output as the output laser;

所述凸透镜接收到透射光后，将透射光沿着所述凸透镜的凸透面向外沿指定角度分散传输，最终传输至所述半球面镜；After the convex lens receives the transmitted light, the transmitted light is dispersed and transmitted along a specified angle outward along the convex transparent surface of the convex lens, and finally transmitted to the hemispherical mirror;

在半球面镜的内侧均匀分布有所述散射增益介质；使得当从所述凸透镜出射的空间光到达所述散射增益介质时，所述空间光在传输过程中会产生较强散射信号；由于光路的可逆性与散射过程的方向随机性，必然存在部分散射信号能反馈回所述激光发生增益单元；相比原始空间激光信号，所述散射增益介质将产生一个预设量的、频域线宽更窄的散射回馈信号，并回馈到所述激光发生增益单元中实现增益放大；增益放大后的光信号在激光振荡过程中将再次从所述激光发生增益单元出射并达到所述半球面镜，与所述散射增益介质接触后再次产生频域线宽更小的散射回馈信号，并再次回馈到所述激光发生增益单元中进行放大。The scattering gain medium is uniformly distributed on the inner side of the hemispherical mirror; so that when the spatial light emitted from the convex lens reaches the scattering gain medium, the spatial light will generate a strong scattering signal during the transmission process; Reversibility and the randomness of the direction of the scattering process, there must be some scattering signals that can be fed back to the laser generating gain unit; compared to the original spatial laser signal, the scattering gain medium will generate a preset amount of linewidth in the frequency domain. The narrow scattering feedback signal is fed back to the laser generating gain unit to achieve gain amplification; the optical signal after gain amplification will be emitted from the laser generating gain unit again during the laser oscillation process and reach the hemispherical mirror. After the scattering gain medium is in contact, a scattering feedback signal with a smaller frequency domain linewidth is generated again, and is fed back to the laser generating gain unit for amplification again.

所述激光发生增益单元用于产生空间激光并将所述的激光信号向外出射，从所述空间耦合透镜将输出的激光信号进行空间耦合并令其按照特定方向进行传输。在传输过程中，激光信号抵达所述半透半反镜，产生透射光与反射光。反射光作为整个***的空间光输出，而透射光继续水平传输至所述凸透镜。所述凸透镜将水平方向传输的透射光改为向外沿着不同方向的激光输出，并到达所述半球面镜。在所述半球面镜的内侧表面均匀分布着所述散射增益介质，使得当从所述凸透镜出射的空间激光到达所述半球面镜的内侧表面时，该表面位置处会产生方向随机的较强散射光信号。由于光路的可逆性与散射过程的方向随机性，必然存在能沿着***反馈回所述激光发生增益单元的散射光信号。所述散射增益介质将产生一个预设量的、频域线宽相比于原始注入信号更窄的散射回馈光信号，并回馈到所述激光发生增益单元中实现增益放大。而增益放大后的光信号在激光振荡过程中将再次出射并达到所述分布式散射回馈单元后产生频域线宽更小的散射回馈信号，以此实现激光线宽的循环深压缩。The laser generating and gaining unit is used to generate spatial laser and emit the laser signal outward, and spatially couple the output laser signal from the spatial coupling lens and make it transmit in a specific direction. During the transmission process, the laser signal reaches the half mirror, generating transmitted light and reflected light. The reflected light is used as the spatial light output of the entire system, and the transmitted light continues to be horizontally transmitted to the convex lens. The convex lens changes the transmitted light transmitted in the horizontal direction to the laser output along different directions outward, and reaches the hemispherical mirror. The scattering gain medium is uniformly distributed on the inner surface of the hemispherical mirror, so that when the spatial laser emitted from the convex lens reaches the inner surface of the hemispherical mirror, strong scattered light with random directions will be generated at the surface position signal. Due to the reversibility of the optical path and the randomness of the direction of the scattering process, there must be a scattered light signal that can be fed back to the laser generating gain unit along the system. The scattering gain medium will generate a predetermined amount of scattering feedback light signal with a narrower frequency domain linewidth than the original injection signal, and feed it back to the laser generating gain unit to achieve gain amplification. The optical signal after gain amplification will be emitted again during the laser oscillation process and reach the distributed scattering feedback unit to generate a scattering feedback signal with a smaller frequency domain linewidth, so as to realize the cyclic deep compression of the laser linewidth.

作为优选，激光发生增益单元接收到来自分布式散射回馈单元的所述后向散射回馈信号对其进行增益，以此来实现激光的深度压缩。其中，分布式散射回馈装置包含各类能加强散射系数的结构或材料。Preferably, the laser generation gain unit receives the backscatter feedback signal from the distributed scattering feedback unit to gain gain, so as to realize the deep compression of the laser. Among them, the distributed scattering feedback device includes various structures or materials that can enhance the scattering coefficient.

作为优选，所述散分布式散射回馈结构在激光谐振过程中为激光原始产生结构提供散射的较强回馈信号。Preferably, the scattered distribution scattering feedback structure provides a strong scattering feedback signal for the original laser generating structure during the laser resonance process.

作为优选，将散射原理与透镜相结合，实现了在三维空间里对空间激光的超窄线宽压缩。Preferably, combining the scattering principle with the lens realizes the ultra-narrow linewidth compression of the spatial laser in the three-dimensional space.

作为优选，利用所述散射增益介质产生散射信号的多重反射特性来实现激光的单纵模输出。Preferably, the multiple reflection characteristics of the scattering signal generated by the scattering gain medium are used to realize the single longitudinal mode output of the laser.

作为优选，通过替换具有不同散射系数的散射增益介质实现对线宽不同程度的深压缩。Preferably, by replacing the scattering gain medium with different scattering coefficients, the deep compression of the line width to different degrees is realized.

本发明中，一种激光器可以是多波长超窄线宽激光器，包括激光发生增益单元、第一密集型波分复用器、光隔离器和第二密集型波分复用器，所述激光发生增益单元中的每个激光发生增益装置分别连接该第一密集型波分复用器的对应第一端，该第一密集型波分复用器的第二端连接所述分布式散射回馈单元的一端；分布式散射回馈单元的另一端连接该第二密集型波分复用器的第一端；所述激光发生增益单元中的每个激光发生增益装置都分别生成对应不同波长的光信号，对生成的光信号进行增益放大，并将增益放大后的光信号传输给所述第一密集型波分复用器，所述第一密集型波分复用器将不同波长的光信号合成一束光信号传输所述分布式散射回馈单元，所述分布式散射回馈单元的另一端输出光信号至所述第二密集型波分复用器；In the present invention, a laser may be a multi-wavelength ultra-narrow linewidth laser, including a laser generating gain unit, a first dense wavelength division multiplexer, an optical isolator, and a second dense wavelength division multiplexer. The laser Each laser generating gain device in the generating gain unit is respectively connected to the corresponding first end of the first dense wavelength division multiplexer, and the second end of the first dense wavelength division multiplexer is connected to the distributed scattering feedback One end of the unit; the other end of the distributed scattering feedback unit is connected to the first end of the second dense wavelength division multiplexer; each laser generating gain device in the laser generating gain unit generates light corresponding to different wavelengths. Signal, the generated optical signal is gain-amplified, and the gain-amplified optical signal is transmitted to the first dense wavelength division multiplexer, and the first dense wavelength division multiplexer combines optical signals of different wavelengths Synthesize a beam of optical signals to transmit the distributed scattering feedback unit, and the other end of the distributed scattering feedback unit outputs the optical signal to the second dense wavelength division multiplexer;

所述分布式散射回馈单元在接收到光信号后，基于散射效应，在分布式散射回馈单元内部波导中各处产生线宽更窄的后向散射光信号。部分散射光信号背向传回所述第一密集型波分复用器，所述第一密集型波分复用器的第二端接受到后向散射光信号后，又将该信号分成多束不同波长的信号，并将对应波长的所述后向散射信号从所述第一密集型波分复用器的第一端口的对应通道输出给所述激光发生增益单元。具有更窄线宽的后向散射光信号在所述激光发生增益阵列中不断地被增益放大，在这个循环不停的过程中实现了对所述激光发生增益单元的线宽的不断压缩，最后所述激光发生增益单元也同样输出更窄的激光线宽，再将增益放大后的对应波长的所述后向散射光信号传输至所述第一密集型波分复用器；优选地，所述分布式散射回馈单元同时对多个波长的激光进行线宽同时压缩。After the distributed scattering feedback unit receives the optical signal, based on the scattering effect, a backscattered light signal with a narrower line width is generated everywhere in the internal waveguide of the distributed scattering feedback unit. Part of the scattered light signal is transmitted back to the first dense wavelength division multiplexer. After receiving the backscattered light signal at the second end of the first dense wavelength division multiplexer, it divides the signal into multiple multiplexers. Beams signals of different wavelengths, and output the backscattered signals of corresponding wavelengths from the corresponding channel of the first port of the first dense wavelength division multiplexer to the laser generating gain unit. The backscattered light signal with a narrower linewidth is continuously amplified by the gain in the laser generating gain array. During this cycle, the linewidth of the laser generating gain unit is continuously compressed, and finally The laser generating gain unit also outputs a narrower laser linewidth, and then transmits the backscattered light signal of the corresponding wavelength after gain amplification to the first dense wavelength division multiplexer; preferably, the The distributed scattering feedback unit simultaneously compresses the line width of lasers of multiple wavelengths at the same time.

所述第二密集型波分复用器在接收到所述光隔离器提供的光信号后，将该光信号分成多束不同波长的光信号，并通过其各个第二端将对应波长的光信号输出。After the second dense wavelength division multiplexer receives the optical signal provided by the optical isolator, it divides the optical signal into multiple optical signals of different wavelengths, and divides the optical signals of the corresponding wavelengths through each of its second ends. Signal output.

一种可选的实现方式中，通过对所述分布式散射回馈单元内部光波导的散射系数进行调节，可以实现用更短的分布式散射回馈单元达成相同或更窄线宽的激光输出。In an optional implementation manner, by adjusting the scattering coefficient of the optical waveguide inside the distributed scattering feedback unit, a shorter distributed scattering feedback unit can be used to achieve laser output with the same or narrower line width.

本发明中，一种激光器可以是可调谐超窄线宽激光器，包括激光发生增益单元、分布式散射回馈单元、第一光准直透镜、第二光准直透镜和可调谐滤波元件，所述激光发生增益单元的第一输出端和第二输出端对应设置有第一薄膜和第二薄膜，所述第一薄膜和第二薄膜都具有透射和反射特性，所述激光发生增益单元的第一输出端依次通过所述第一薄膜、第一光准直透镜连接所述分布式散射回馈单元的第一端，所述激光发生增益单元的所述第二输出端依次通过所述第二薄膜、第二光准直透镜连接所述可调谐滤波元件；In the present invention, a laser may be a tunable ultra-narrow linewidth laser, including a laser generating gain unit, a distributed scattering feedback unit, a first optical collimating lens, a second optical collimating lens, and a tunable filter element. The first output end and the second output end of the laser generating gain unit are correspondingly provided with a first film and a second film, the first film and the second film both have transmission and reflection characteristics, and the first output end of the laser generating gain unit The output end is connected to the first end of the distributed scattering feedback unit through the first film and the first light collimating lens in sequence, and the second output end of the laser generating gain unit sequentially passes through the second film, The second optical collimator lens is connected to the tunable filter element;

所述激光发生增益单元用于生成宽光谱的初始激光信号并分别传输给所述第一薄膜和第二薄膜，所述第一薄膜在接收到初始激光信号后，将一部分光信号传输给所述激光发生增益单元，另一部分通过所述第一光准直透镜传输给所述分布式散射回馈单元；所述第二薄膜在接收到初始激光信号后，将一部分光信号传输给所述激光发生增益单元，另一部分通过所述第二光准直透镜传输给所述可调谐滤波元件；The laser generating and gaining unit is used to generate a broad-spectrum initial laser signal and transmit it to the first film and the second film respectively. After receiving the initial laser signal, the first film transmits a part of the optical signal to the The laser generating gain unit, and the other part is transmitted to the distributed scattering feedback unit through the first light collimating lens; after receiving the initial laser signal, the second film transmits a part of the optical signal to the laser generating gain Unit, the other part is transmitted to the tunable filter element through the second light collimating lens;

所述可调谐滤波元件在接收到初始激光信号后，对初始激光信号进行波长选择和调谐，获得具有特定波长光信号，所述具有特定波长光信号一部分通过所述第二光准直透镜传输给所述第二薄膜，另一部分直接输出；所述分布式散射回馈单元的第一端在接收到另一部分光信号后，对所述另一部分光信号进行线宽压缩，并通过所述第一光准直透镜将线宽压缩后的后向散射光信号传输给所述第一薄膜；所述激光发生增益单元在接收到回馈的后向散射光信号后，对后向散射光信号进行增益放大，并将增益放大后的后向散射光信号再次分别传输给所述第一薄膜和第二薄膜；在达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述可调谐滤波元件的另一端输出。After the tunable filter element receives the initial laser signal, it performs wavelength selection and tuning on the initial laser signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength is transmitted to the second optical collimator lens. The other part of the second film is directly output; after receiving another part of the optical signal, the first end of the distributed scattering feedback unit performs linewidth compression on the other part of the optical signal, and passes the first optical signal. The collimating lens transmits the backscattered light signal after linewidth compression to the first film; the laser generating gain unit receives the feedback backscattered light signal, and then performs gain amplification on the backscattered light signal, And transmit the backscattered light signal after gain amplification to the first film and the second film respectively; when reaching a steady state, the light signal with a specific wavelength passes through the distributed scattering feedback unit cyclic linewidth compression Then, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the other end of the tunable filter element.

在一种可选的实现方式中，所述分布式散射回馈单元还可以通过所述分布式散射回馈单元的第二端将线宽压缩后向前传输的光信号输出。In an optional implementation manner, the distributed scattering feedback unit may also output the optical signal transmitted forward after the line width is compressed through the second end of the distributed scattering feedback unit.

本发明中，一种激光器可以是片上超窄线宽激光器，包括激光发生增益单元、分布式散射回馈单元、第一光准直透镜、第二光准直透镜和可调谐滤波元件，所述激光发生增益单元的第一输出端和第二输出端对应设置有第一薄膜和第二薄膜，所述第一薄膜具有透射和反射特性，所述第二薄膜具有反射特性，所述激光发生增益单元的第一输出端依次通过所述第一薄膜、第一光准直透镜连接所述分布式散射回馈单元的第一端，激光发生增益单元的第二输出端连接所述第二薄膜，所述分布式散射回馈单元的第二端连接所述可调谐滤波元件；In the present invention, a laser may be an on-chip ultra-narrow linewidth laser, including a laser generating gain unit, a distributed scattering feedback unit, a first optical collimating lens, a second optical collimating lens, and a tunable filter element. The first output end and the second output end of the generating gain unit are provided with a first film and a second film correspondingly, the first film has transmission and reflection characteristics, the second film has reflection characteristics, and the laser generating gain unit The first output end of the laser light generating unit is connected to the first end of the distributed scattering feedback unit through the first film and the first light collimating lens in turn, and the second output end of the laser generating gain unit is connected to the second film, the The second end of the distributed scattering feedback unit is connected to the tunable filter element;

所述激光发生增益单元用于生成宽光谱的初始激光信号并分别传输给所述第一薄膜和第二薄膜，所述第一薄膜在接收到初始激光信号后，将一部分光信号反射回所述激光发生增益单元，另一部分通过所述第一光准直透镜和所述分布式散射回馈单元传输至所述可调谐滤波单元；所述第二薄膜在接收到初始激光信号后，将所述初始激光信号部分传输给所述激光发生增益单元；所述可调滤波单元接受到初始激光信号后，对初始激光信号进行波长的选择并调谐，以选择出具有特定波长光信号，所述具有特定波长光信号沿原光路返回至所述激光发生增益单元；所述激光发生增益单元接收所述具有特定波长光信号对所述具特定波长的光线号进行增益放大，并将增益放大后的具有特定波长光信号再次通过所述第一光准直透镜传输至所述分布式散射回馈单元；所述分布式散射回馈单元的第一端在接收到具有特定波长光信号后，对具有特定波长光信号进行线宽压缩，并通过所述第一光准直透镜将线宽压缩后的后向的散射光信号传输给所述激光发生增益单元进行增益放大；而将线宽压缩后前向传输的光信号传输至可调谐滤波单元，并通过可调谐滤波单元的第二端输出；在达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述可调谐滤波元件输出。The laser generating and gaining unit is used to generate a broad-spectrum initial laser signal and transmit it to the first film and the second film respectively. After receiving the initial laser signal, the first film reflects a part of the optical signal back to the The laser generating gain unit, the other part is transmitted to the tunable filter unit through the first optical collimator lens and the distributed scattering feedback unit; after the second film receives the initial laser signal, the initial laser The laser signal is partially transmitted to the laser generating gain unit; after receiving the initial laser signal, the tunable filter unit selects and tunes the wavelength of the initial laser signal to select an optical signal with a specific wavelength, which has a specific wavelength The optical signal returns to the laser generating gain unit along the original optical path; the laser generating gain unit receives the optical signal with a specific wavelength to perform gain amplification on the light signal with the specific wavelength, and the amplified light signal with the specific wavelength The optical signal is again transmitted to the distributed scattering feedback unit through the first optical collimator lens; the first end of the distributed scattering feedback unit receives an optical signal with a specific wavelength, and performs processing on the optical signal with a specific wavelength. The line width is compressed, and the backward scattered light signal after the line width compression is transmitted to the laser generating gain unit for gain amplification through the first optical collimator lens; and the optical signal transmitted forward after the line width is compressed It is transmitted to the tunable filter unit and output through the second end of the tunable filter unit; when it reaches a steady state, the optical signal with a specific wavelength is compressed by the distributed scattering feedback unit to obtain a single longitudinal The mode ultra-narrow linewidth optical signal is output from the tunable filter element.

在一种可选的实现方式中，所述第二薄膜还具有透射特性，所述第二薄膜还与第二光准直透镜连接，所述第二薄膜在接收到光信号后，将所述光信号的一部分传输给所述激光发生增益单元，另一部分通过所述第二光准直透镜输出。In an optional implementation manner, the second film also has transmission characteristics, the second film is also connected to a second light collimating lens, and after receiving the optical signal, the second film A part of the optical signal is transmitted to the laser generating gain unit, and the other part is output through the second optical collimator lens.

在另一种可选的实现方式中，还包括光隔离器，所述可调谐滤波元件与所述光隔离器连接，用于通过所述光隔离器将获得的单纵模超窄线宽光信号输出。In another optional implementation manner, an optical isolator is further included, and the tunable filter element is connected to the optical isolator for the single longitudinal mode ultra-narrow linewidth light obtained through the optical isolator. Signal output.

在另一种可选的实现方式中，所述分布式散射回馈单元包括具有高散射系数的特殊光纤、特殊气体材料制成的波导结构，或者是刻写在基板上的特殊散射波导。In another optional implementation manner, the distributed scattering feedback unit includes a special optical fiber with a high scattering coefficient, a waveguide structure made of a special gas material, or a special scattering waveguide written on a substrate.

在另一种可选的实现方式中，通过所述分布式散射回馈单元来实现激光波长与有效分布式散射结构中腔长的自匹配；所述分布式散射回馈单元是以瑞利散射为代表的所有分布式散射机制，通过对所述分布式散射回馈单元的散射系数和信号回馈比例进行调节，实现光信号线宽的循环压缩调节。In another optional implementation manner, the distributed scattering feedback unit is used to realize the self-matching of the laser wavelength and the cavity length in the effective distributed scattering structure; the distributed scattering feedback unit is represented by Rayleigh scattering All the distributed scattering mechanisms of the distributed scattering feedback unit realize the cyclic compression adjustment of the optical signal line width by adjusting the scattering coefficient and the signal feedback ratio of the distributed scattering feedback unit.

在另一种可选的实现方式中，所述激光发生增益单元包括增益介质，所述增益介质在电激励作用下生成宽光谱的初始激光信号分别传输给所述第一薄膜和第二薄膜，其在接收到光信号后，在激光谐振过程中，对该光信号进行增益放大，并将增益放大后的光信号再次分别传输给所述第一薄膜和第二薄膜。In another optional implementation manner, the laser generating gain unit includes a gain medium, and the gain medium generates a broad-spectrum initial laser signal under electrical excitation and transmits it to the first thin film and the second thin film, respectively, After receiving the optical signal, in the laser resonance process, the optical signal is gain-amplified, and the gain-amplified optical signal is again transmitted to the first film and the second film respectively.

在另一种可选的实现方式中，所述激光发生增益单元、分布式散射回馈单元、第一光准直透镜、第二光准直透镜和可调谐滤波单元中至少所述激光发生增益单元、分布式散射回馈单元、第一光准直透镜和第二光准直透镜集成在基板上。In another optional implementation manner, at least the laser generation gain unit among the laser generation gain unit, the distributed scattering feedback unit, the first optical collimator lens, the second optical collimator lens, and the tunable filter unit , The distributed scattering feedback unit, the first light collimating lens and the second light collimating lens are integrated on the substrate.

在另一种可选的实现方式中，所述激光发生增益单元可覆盖激光增益的任意波段，该压缩机制不具波长的选择性，适用于任意波段和任意类型激光线宽的深压缩。In another optional implementation manner, the laser generating gain unit can cover any wavelength band of laser gain, and the compression mechanism does not have wavelength selectivity, and is suitable for deep compression of any wavelength band and any type of laser linewidth.

本发明中，一种激光器可以是片上超窄线宽激光器，包括激光发生增益单元、分布式散射回馈单元、第一光准直透镜和第二光准直透镜，所述激光发生增益单元的第一输出端通过所述第一光准直透镜连接所述分布式散射回馈单元的第一端，激光发生增益单元的第二输出端连接所述第二光准直透镜的第一端；所述激光发生增益单元用于生成宽光谱的初始光信号，并对生成的光信号进行波长选择，获得具有特定波长光信号，所述具有特定波长光信号的一部分通过所述第一光准直透镜传输给所述分布式散射回馈单元的第一端，另一部分通过所述第二光准直透镜输出；In the present invention, a laser may be an on-chip ultra-narrow linewidth laser, including a laser generating gain unit, a distributed scattering feedback unit, a first optical collimating lens and a second optical collimating lens. The first optical collimating lens of the laser generating gain unit An output end is connected to the first end of the distributed scattering feedback unit through the first light collimating lens, and the second output end of the laser generating gain unit is connected to the first end of the second light collimating lens; The laser generating gain unit is used to generate a broad-spectrum initial optical signal, and perform wavelength selection on the generated optical signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength is transmitted through the first optical collimator lens To the first end of the distributed scattering feedback unit, the other part is output through the second light collimating lens;

所述分布式散射回馈单元的第一端在接收到具有特定波长光信号后，对该光信号进行线宽压缩，并通过所述第一光准直透镜将线宽压缩后的后向散射光信号传输给所述激光发生增益单元，所述激光发生增益单元在接收到回馈的后向散射光信号后，对回馈的光信号进行增益放大，针对增益放大后的光信号，将其一部分通过所述第二光准直透镜输出，另一部分通过所述第一光准直透镜再次传输给所述分布式散射回馈单元的第一端做进一步线宽压缩，当达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述第二光准直透镜输出。After the first end of the distributed scattering feedback unit receives an optical signal with a specific wavelength, it performs linewidth compression on the optical signal, and compresses the backscattered light after the linewidth is compressed by the first optical collimator lens The signal is transmitted to the laser generating gain unit. After the laser generating gain unit receives the feedback backscattered light signal, it gains and amplifies the feedback optical signal, and for the gain-amplified optical signal, a part of it passes through all the optical signals. The second light collimating lens outputs, and the other part is retransmitted to the first end of the distributed scattering feedback unit through the first light collimating lens for further linewidth compression. When it reaches a steady state, the After the wavelength optical signal is cyclically compressed by the distributed scattering feedback unit, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the second optical collimator lens.

在一种可选的实现方式中，所述分布式散射回馈单元包括具有高散射系数的特殊光纤、特殊气体材料波导，或刻写在基底上的特殊散射波导。In an optional implementation manner, the distributed scattering feedback unit includes a special optical fiber with a high scattering coefficient, a special gas material waveguide, or a special scattering waveguide written on a substrate.

在另一种可选的实现方式中，通过对所述分布式散射回馈单元的散射系数和信号回馈比例进行调节，实现光信号线宽的深压缩和单纵模输出。In another optional implementation manner, by adjusting the scattering coefficient and the signal feedback ratio of the distributed scattering feedback unit, deep compression of the optical signal linewidth and single longitudinal mode output are realized.

在另一种可选的实现方式中，所述激光发生增益单元包括增益介质和光纤光栅(FBG)，所述增益介质在电激励作用下生成宽光谱的初始激光信号，生成的初始激光信号传输给所述光纤光栅，所述光纤光栅对生成的初始激光信号进行波长选择，获得具有特定波长光信号，所述具有特定波长光信号一部分通过所述第一光准直透镜传输给所述分布式散射回馈单元的第一端，另一部分通过所述第二光准直透镜输出；In another optional implementation manner, the laser generating gain unit includes a gain medium and a fiber grating (FBG). The gain medium generates a broad-spectrum initial laser signal under electrical excitation, and the generated initial laser signal is transmitted For the fiber grating, the fiber grating performs wavelength selection on the generated initial laser signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength is transmitted to the distributed system through the first optical collimator lens. The first end of the scattering feedback unit, and the other part is output through the second light collimating lens;

所述分布式散射回馈单元的第一端在接收到具有特定波长光信号，对该光信号进行线宽压缩后，依次通过所述第一光准直透镜、所述光纤光栅将线宽压缩后的后向散射光信号传输给所述增益介质，所述增益介质在接收到回馈的所述后向散射光信号后，对回馈的所述后向散射光信号进行增益放大，针对增益放大后的光信号，将其一部分依次通过所述光纤光栅、第二光准直透镜输出，另一部分依次通过所述光纤光栅、第一光准直透镜再次传输给所述分布式散射回馈单元的第一端做进一步线宽压缩。After the first end of the distributed scattering feedback unit receives an optical signal with a specific wavelength, the optical signal is line-width compressed, and then the line-width is compressed through the first optical collimator lens and the fiber grating in sequence The backscattered light signal is transmitted to the gain medium. After receiving the backscattered light signal, the gain medium performs gain amplification on the backscattered light signal that is fed back. A part of the optical signal is output through the fiber grating and the second light collimating lens in turn, and the other part is transmitted to the first end of the distributed scattering feedback unit through the fiber grating and the first light collimating lens in turn. Do further line width compression.

在另一种可选的实现方式中，还包括第一光隔离器，所述第二光准直透镜的第二端连接所述第一光隔离器。In another optional implementation manner, a first optical isolator is further included, and the second end of the second optical collimating lens is connected to the first optical isolator.

在另一种可选的实现方式中，还包括第二光隔离器，所述分布式散射回馈单元的第二端连接所述第二光隔离器，所述分布式散射回馈单元的第一端在接收到光信号，对该光信号进行线宽压缩后，并将线宽压缩后向后传输的激光信号通过所述第一光准直透镜传输至所述激光发生增益单元进行增益放大；将线宽压缩后向前传输的光信号通过所述第二光隔离器输出；当达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述第二光隔离器输出。In another optional implementation manner, it further includes a second optical isolator, the second end of the distributed scattering feedback unit is connected to the second optical isolator, and the first end of the distributed scattering feedback unit After receiving the optical signal, compressing the line width of the optical signal, and transmitting the laser signal transmitted backward through the first optical collimator lens to the laser generating gain unit for gain amplification; The optical signal transmitted forward after the line width compression is output through the second optical isolator; when it reaches a steady state, the optical signal with a specific wavelength is cyclically compressed by the distributed scattering feedback unit to obtain a single The longitudinal mode ultra-narrow linewidth optical signal is output from the second optical isolator.

在另一种可选的实现方式中，所述分布式散射回馈单元是包括瑞利散射在内的所有分布式散射机制，通过所述分布式散射回馈单元来实现激光波长与有效分布式反馈结构中腔长的自匹配。In another optional implementation manner, the distributed scattering feedback unit is all distributed scattering mechanisms including Rayleigh scattering, and the laser wavelength and effective distributed feedback structure are realized through the distributed scattering feedback unit Self-matching of the cavity length.

在另一种可选的实现方式中，所述激光发生增益单元的增益介质可覆盖激光增益的任意波段，其不具波长的选择性，适用于任意波段和任意类型激光线宽的深压缩。In another optional implementation manner, the gain medium of the laser generating gain unit can cover any wavelength band of the laser gain, which has no wavelength selectivity, and is suitable for deep compression of any wavelength band and any type of laser linewidth.

在另一种可选的实现方式中，所述激光发生增益单元、分布式散射回馈单元、第一光准直透镜、第二光准直透镜、第一光隔离器和第二光隔离器中至少激光发生增益单元、分布式散射回馈单元、第一光准直透镜和第二光准直透镜集成在基板上。In another optional implementation manner, the laser generating gain unit, the distributed scattering feedback unit, the first optical collimating lens, the second optical collimating lens, the first optical isolator and the second optical isolator At least the laser generating gain unit, the distributed scattering feedback unit, the first light collimating lens and the second light collimating lens are integrated on the substrate.

有益效果在于：The beneficial effects are:

1、本发明中的激光器，基于空间光散射回馈结构，通过采用散射原理与空间耦合透镜结合实现了在三维空间上实现了对激光线宽的直接深压缩，实现了整体***更小的体积、更好的稳定性和更广的结构扩展性。1. The laser in the present invention is based on the spatial light scattering feedback structure, and realizes the direct deep compression of the laser linewidth in the three-dimensional space by combining the scattering principle and the spatial coupling lens, and realizes a smaller volume and a smaller volume of the overall system. Better stability and wider structural scalability.

另外，本发明利用所述分布式散射回馈单元在激光振荡过程中回馈相比于原始注入信号更窄的信号来实现对线宽的深压缩，最终获得不具有波长选择性，且具有较高边摸抑制比(Side-Mode Suppression Ratio)的超窄线宽激光输出。In addition, the present invention uses the distributed scattering feedback unit to feed back a signal that is narrower than the original injection signal during the laser oscillation process to achieve deep compression of the line width, and finally obtains that it does not have wavelength selectivity and has a higher edge. Ultra-narrow linewidth laser output with side-mode suppression ratio (Side-Mode Suppression Ratio).

2、本发明中的一个激光器，基于分布式散射回馈单元的多波长超窄线宽激光器，通过采用散射原理与多波长阵列式结构结合，实现了单个线宽压缩***对多波长激光线宽的同时压缩，实现了整体***更高的集成度、更好的稳定性和更广的结构扩展性；本发明利用分布式散射回馈单元为激光谐振腔提供回馈信号，具有波长无关性，可以实现一个压缩***对任意波长激光的线宽压缩；本发明利用所分布式散射回馈单元在激光振荡过程中回馈相比于原始注入信号更窄的信号来实现对线宽的深压缩，最终获得超窄线宽激光输出。2. A laser in the present invention is a multi-wavelength ultra-narrow linewidth laser based on a distributed scattering feedback unit. By combining the scattering principle with a multi-wavelength array structure, a single linewidth compression system realizes the effect of a single linewidth compression system on the linewidth of a multi-wavelength laser Simultaneous compression realizes higher integration, better stability and wider structural scalability of the overall system; the present invention uses distributed scattering feedback units to provide feedback signals for the laser resonator, which is wavelength-independent and can achieve a The compression system compresses the line width of any wavelength laser; the present invention uses the distributed scattering feedback unit to feed back a signal that is narrower than the original injection signal during the laser oscillation process to achieve deep compression of the line width, and finally obtain an ultra-narrow line Wide laser output.

3、本发明中的一个激光器，片上超窄线宽激光器，通过利用分布式散射回馈单元的分布式回馈特性，实现了激光增益过程中激光波长与反馈腔长的自适应过程。另外，在此基础上，以瑞利散射为代表的分布式散射回馈信号相比于初始入射信号具有更窄的线宽，在激光振荡过程中具由循环压缩特性。因此，相比于传统方法，本发明能够在实现激光模式选择的同时获得激光线宽的深压缩；3. One of the lasers of the present invention, the on-chip ultra-narrow linewidth laser, realizes the adaptive process of laser wavelength and feedback cavity length in the laser gain process by using the distributed feedback characteristics of the distributed scattering feedback unit. In addition, on this basis, the distributed scattering feedback signal represented by Rayleigh scattering has a narrower line width than the initial incident signal, and has the characteristic of cyclic compression during laser oscillation. Therefore, compared with the traditional method, the present invention can achieve deep compression of the laser linewidth while realizing the selection of the laser mode;

通过将本发明的组件集成与基板上，实现了窄线宽激光器***的集成化，小型化。为实现性能稳定的便携式超窄线宽激光器的发展提供了可能。By integrating the components of the present invention on the substrate, the integration and miniaturization of the narrow linewidth laser system are realized. It is possible to realize the development of portable ultra-narrow linewidth lasers with stable performance.

4、本发明中的一个激光器，可调谐超窄线宽激光器，通过在激光***中设置一个可调谐滤波元件来实现具有波长可调谐特性的激光信号。在此基础上，基于激光振荡过程中分布式散射回馈单元的循环压缩特性，以实现激光波长调谐过程中对不同波长激光线宽的深压缩，以满足不同的应用需求。通过将各个组件集成于基板上，可以实现集成化，提高***稳定性。4. A laser in the present invention, a tunable ultra-narrow linewidth laser, realizes a laser signal with wavelength tunable characteristics by setting a tunable filter element in the laser system. On this basis, based on the cyclic compression characteristics of the distributed scattering feedback unit in the laser oscillation process, the deep compression of the laser linewidth of different wavelengths in the laser wavelength tuning process is realized to meet different application requirements. By integrating various components on the substrate, integration can be achieved and system stability can be improved.

附图说明Description of the drawings

图1为本发明实施例中激光深度压缩的原理流程图；Figure 1 is a flow chart of the principle of laser deep compression in an embodiment of the present invention;

图2为本发明中基于空间光散射回馈结构的超窄线宽激光器的一个实施例结构示意图；2 is a schematic structural diagram of an embodiment of an ultra-narrow linewidth laser based on a spatial light scattering feedback structure in the present invention;

图3为本发明中多波长超窄线宽激光器的一个实施例结构示意图；Fig. 3 is a schematic structural diagram of an embodiment of a multi-wavelength ultra-narrow linewidth laser in the present invention;

图4为本发明中片上超窄线宽激光器的一个实施例结构示意图；4 is a schematic structural diagram of an embodiment of the on-chip ultra-narrow linewidth laser in the present invention;

图5为本发明中片上超窄线宽激光器的另一个实施例结构示意图；5 is a schematic structural diagram of another embodiment of the on-chip ultra-narrow linewidth laser in the present invention;

图6为本发明中可调谐超窄线宽激光器的一个实施例结构示意图；6 is a schematic structural diagram of an embodiment of a tunable ultra-narrow linewidth laser in the present invention;

图7为本发明中可调谐超窄线宽激光器的另一个实施例结构示意图。Fig. 7 is a schematic structural diagram of another embodiment of a tunable ultra-narrow linewidth laser in the present invention.

图中各个标记所对用的名称分别为：激光发生结构1，空间耦合透镜2，半透半反镜片3，凸透镜4，散射增益介质5，以及半球面镜6；激光发生增益装置7、第一密集型波分复用器8、散射回馈装置9、光隔离器10、第二密集型波分复用器11；激光生成增益单元12、第一光准直透镜13、分布式散射回馈单元14、第二光准直透镜15、可调谐滤波单元16、光隔离器17、第一薄膜1200、第二薄膜1201、增益介质1202；18、分布式散射回馈单元，19、第一光准直透镜，20、激光发生增益单元，21、第二光准直透镜，22、光隔离器，300、增益介质，301、FBG。The names used for each mark in the figure are: laser generating structure 1, spatial coupling lens 2, transflective lens 3, convex lens 4, scattering gain medium 5, and hemispherical mirror 6; laser generating gain device 7, first Dense wavelength division multiplexer 8, scattering feedback device 9, optical isolator 10, second dense wavelength division multiplexer 11; laser generating gain unit 12, first optical collimator lens 13, distributed scattering feedback unit 14 1. The second light collimating lens 15, the tunable filter unit 16, the optical isolator 17, the first film 1200, the second film 1201, the gain medium 1202; 18. The distributed scattering feedback unit, 19, the first light collimating lens , 20, laser generating gain unit, 21, second optical collimator lens, 22, optical isolator, 300, gain medium, 301, FBG.

为了更清楚地说明本发明具体实施方式或现有技术中的技术方案，下面将对具体实施方式或现有技术描述中所需要使用的附图作简单地介绍。在所有附图中，类似的元件或部分一般由类似的附图标记标识。附图中，各元件或部分并不一定按照实际的比例绘制。In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to actual scale.

具体实施方式Detailed ways

下面将对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明的一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

需要说明的是，本发明实施例中所有方向性指示(诸如上、下、左、右、前、后……)仅用于解释在某一特定姿态(如附图所示)下各部件之间的相对位置关系、运动情况等，如果该特定姿态发生改变时，则该方向性指示也相应地随之改变。It should be noted that all the directional indicators (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the difference between the components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the relative positional relationship, movement conditions, etc., the directional indication will also change accordingly.

另外，在本发明中如涉及“第一”、“第二”等的描述仅用于描述目的，而不能理解为指示或暗示其相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括至少一个该特征。在本发明的描述中，“多个”的含义是至少两个，例如两个，三个等，除非另有明确具体的限定。In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

下面将结合附图，对本发明的优选实施例进行详细的描述。The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

本发明中，参考图1和图2所示的流程图，本发明进行激光深度压缩的原理在于激光信号反馈，具体方法包括以下步骤：In the present invention, referring to the flowcharts shown in Figs. 1 and 2, the principle of laser deep compression in the present invention lies in laser signal feedback, and the specific method includes the following steps:

1)激光发生增益单元发出激光；1) The laser generating gain unit emits laser light;

2)发出的激光经过分布式散射回馈单元，对输入的光信号进行线宽的压缩，并将线宽压缩后的后向散射信号回馈到激光发生增益单元；2) The emitted laser light passes through the distributed scattering feedback unit to compress the line width of the input optical signal, and the backscatter signal after the line width compression is fed back to the laser generating gain unit;

3)激光发生增益单元接收到回馈的线宽压缩后的光信号后对其进行增益放大，并将增益放大后的光信号再次传输至分布式散射回馈单元。3) The laser generating gain unit receives the feedback linewidth compressed optical signal and then gains it, and transmits the gain amplified optical signal to the distributed scattering feedback unit again.

运用该方法的激光器，主要包含有激光发生增益单元以及分布式散射回馈单元。具体的实施方式参考以下四个实施方式。The laser using this method mainly includes a laser generating gain unit and a distributed scattering feedback unit. For specific implementations, refer to the following four implementations.

实施例1：Example 1:

图2是本发明基于空间光散射回馈结构的超窄线宽激光器的一个结构示意图。该超窄线宽激光器包括激光发生结构(激光发生增益单元)1，空间耦合透镜2，半透半反镜片3，凸透镜4，散射增益介质5，以及半球面镜6。散射增益介质5，以及半球面镜6组成分布式散射回馈单元，其中所述激光发生增益单元1包括常规光学腔与面上芯片等所有可形成激光的结构，且内部没有空间光隔离器，有利于接收后续的反馈信号。所述激光发生结构1产生激光后出射到空间耦合透镜2，空间内的激光经耦合后在特定空间范围内传输。空间光之后传输到所述半透半反镜片3，并产生对应的透射光与反射光，其中透射光继续传输至所述凸透镜4，而反射光则作为该结构的最终激光输出。所述凸透镜4接收到透射光后，将光沿着凸透面向外沿指定角度分散传输，最终传输至所述半球面镜6。在半球面镜6的内侧均匀分布有所述散射增益介质5，从而当激光传输至所述半球面镜6的内侧表面时产生较强的散射信号。由于光路的可逆性以及散射的方向随机性，必然有散射信号沿着***的光路传输回到所述激光发生增益单元1。相比原始激光信号，所述散射增益介质5将产生一个预设量的、频域线宽相比于原始注入信号更窄的散射回馈信号，并回馈到所述激光发生结构1中实现增益放大。由于空间激光到达所述散射增益介质5时都会产生一个频域线宽更小的散射回馈信号并反馈回所述激光发生增益单元1中实现放大，则激光线宽在这个过程中将实现无数次的循环压缩。Fig. 2 is a schematic diagram of the structure of the ultra-narrow linewidth laser based on the spatial light scattering feedback structure of the present invention. The ultra-narrow linewidth laser includes a laser generating structure (laser generating gain unit) 1, a spatial coupling lens 2, a transflective lens 3, a convex lens 4, a scattering gain medium 5, and a hemispherical mirror 6. The scattering gain medium 5 and the hemispherical mirror 6 form a distributed scattering feedback unit. The laser generating gain unit 1 includes conventional optical cavities and on-surface chips and other structures that can form lasers, and there is no spatial optical isolator inside, which is beneficial to Receive subsequent feedback signals. The laser generating structure 1 generates laser light and then emits it to the spatial coupling lens 2, and the laser light in the space is coupled and transmitted within a specific space range. The space light is then transmitted to the transflective lens 3, and corresponding transmitted light and reflected light are generated. The transmitted light continues to be transmitted to the convex lens 4, and the reflected light is used as the final laser output of the structure. After the convex lens 4 receives the transmitted light, it disperses and transmits the light along a specified angle outward along the convex transparent surface, and finally transmits to the hemispherical mirror 6. The scattering gain medium 5 is uniformly distributed on the inner side of the hemispherical mirror 6, so that when the laser light is transmitted to the inner surface of the hemispherical mirror 6, a strong scattering signal is generated. Due to the reversibility of the optical path and the randomness of the scattering direction, a scattered signal must be transmitted back to the laser generating gain unit 1 along the optical path of the system. Compared with the original laser signal, the scattering gain medium 5 will generate a predetermined amount of scattering feedback signal with a narrower frequency domain linewidth than the original injection signal, and feed it back to the laser generating structure 1 to achieve gain amplification . Since the space laser will generate a scattering feedback signal with a smaller frequency domain linewidth when it reaches the scattering gain medium 5 and feed it back to the laser generating gain unit 1 for amplification, the laser linewidth will be realized countless times in this process. Cyclic compression.

需要注意的是：所述散射累积光纤包含各类能加强散射系数的结构或材料。本专利所提供的技术对半导体类型和光纤激光增益类型的原始激光发生结构都适用。It should be noted that the scattering accumulation optical fiber includes various structures or materials that can enhance the scattering coefficient. The technology provided by this patent is applicable to the original laser generating structure of the semiconductor type and the fiber laser gain type.

实施例2：Example 2:

参见图1，为本发明多波长超窄线宽激光器的一个结构示意图。该多波长超窄线宽激光器可以包括激光发生增益装置阵列7(激光发生增益单元)、第一密集型波分复用器8、分布式散射回馈单元9、光隔离器10、第二密集型波分复用器11，所述激光发生增益装置阵列7中的每个激光发生增益装置分别连接该第一密集型波分复用器8的对应第一端，该第一密集型波分复用器8的第二端连接所述分布式散射回馈单元9的一端。所述分布式散射回馈单元9的另一端通过所述光隔离器10后连接该第二密集型波分复用器11的第一端。所述激光发生增益装置阵列7中的每个激光发生增益装置都分别生成对应不同波长的光信号，对生成的光信号进行增益放大，并将增益放大后的光信号传输给所述第一密集型波分复用器8，所述第一密集型波分复用器8将不同波长的光信号合成一束光信号传输给所述分布式散射回馈单元9.光信号再通过所述光隔离器10传输给所述第二密集型波分复用器11；所述分布式散射回馈单元9在接收到光信号后，基于散射效应，在光纤中各处产生线宽更窄的后向散射信号。所述第一密集型波分复用器的第二端接受到后向散射信号后，又将该信号分成多束不同波长的信号，并将对应波长的散射信号从所述第一密集型波分复用器的第一端口的对应通道输出给所述激光发生增益装置阵列。具有更窄线宽的后向散射信号在所述激光发生增益阵列中不断地被增益放大，在这个循环不停的过程中实现了对所述激光发生增益装置阵列的线宽的不断压缩，最后所述激光发生增益装置阵列也同样输出更窄的激光线宽。具有更窄线宽的光信号最后通过所述光隔离器10传输给所述第二密集型波分复用器11；所述第二密集型波分复用器11在接收到所述光隔离器10提供的光信号后，将该光信号分成多束不同波长的光信号，并通过其各个第二端将对应波长的光信号输出。Refer to Fig. 1, which is a schematic diagram of the structure of the multi-wavelength ultra-narrow linewidth laser of the present invention. The multi-wavelength ultra-narrow linewidth laser may include a laser generating gain device array 7 (laser generating gain unit), a first dense wavelength division multiplexer 8, a distributed scattering feedback unit 9, an optical isolator 10, and a second dense The wavelength division multiplexer 11, each laser generation gain device in the laser generation gain device array 7 is respectively connected to the corresponding first end of the first dense wavelength division multiplexer 8, and the first dense wavelength division multiplexer The second end of the user 8 is connected to one end of the distributed scattering feedback unit 9. The other end of the distributed scattering feedback unit 9 is connected to the first end of the second dense wavelength division multiplexer 11 after passing through the optical isolator 10. Each laser generating gain device in the laser generating gain device array 7 respectively generates optical signals corresponding to different wavelengths, performs gain amplification on the generated optical signals, and transmits the gain amplified optical signals to the first dense Type wavelength division multiplexer 8, the first dense wavelength division multiplexer 8 combines optical signals of different wavelengths into a beam of optical signals and transmits them to the distributed scattering feedback unit 9. The optical signals are then isolated by the light The device 10 is transmitted to the second dense wavelength division multiplexer 11; after the distributed scattering feedback unit 9 receives the optical signal, based on the scattering effect, it generates backscattering with a narrower line width everywhere in the optical fiber signal. After receiving the backscattered signal at the second end of the first dense wavelength division multiplexer, it divides the signal into multiple signals of different wavelengths, and separates the scattered signal of the corresponding wavelength from the first dense wave The corresponding channel of the first port of the division multiplexer is output to the laser generating gain device array. The backscattered signal with a narrower line width is continuously amplified by the gain in the laser generating gain array, and the continuous compression of the line width of the laser generating gain device array is realized during this cycle of non-stop process, and finally The laser generating gain device array also outputs a narrower laser line width. The optical signal with a narrower line width is finally transmitted to the second dense wavelength division multiplexer 11 through the optical isolator 10; the second dense wavelength division multiplexer 11 receives the optical isolation After the optical signal provided by the device 10, the optical signal is divided into multiple optical signals of different wavelengths, and the optical signals of the corresponding wavelengths are output through the respective second ends of the optical signals.

本实施例中，激光发生增益装置阵列7中各个激光发生增益装置生成的光信号，除波长不同外，其各项光学特性参数均一致，同时其内部未设置隔离器，以便接收后续反射回的反馈信号。该分布式散射回馈单元9可以包含常规单模光纤，大数值空间光纤，多模光纤等任意能在内部形成散射的光波导结构或其他结构，通过对所述散射回馈装置内部波导的散射系数进行调节，可以实现用更小的分布式散射回馈单元达成相同或更窄线宽的激光输出。通过散射回馈装置产生的后向回馈信号的多重反射特性来实现激光的单纵模输出。此外，本发明采用密集型波分复用器为主体的阵列式结构，结合散射的波长无关性，可以实现多个不同波长光信号的同时线宽压缩。In this embodiment, the optical signal generated by each laser generating gain device in the laser generating gain device array 7 has the same optical characteristic parameters except for the different wavelengths. At the same time, there is no internal isolator to receive subsequent reflections. Feedback signal. The distributed scattering feedback unit 9 may include conventional single-mode optical fibers, large-value spatial optical fibers, multi-mode optical fibers, and other optical waveguide structures or other structures that can form scattering internally, by measuring the scattering coefficient of the internal waveguide of the scattering feedback device. Adjustment can achieve laser output with the same or narrower line width with a smaller distributed scattering feedback unit. The single longitudinal mode output of the laser is realized by the multiple reflection characteristics of the backward feedback signal generated by the scattering feedback device. In addition, the present invention adopts an array structure with a dense wavelength division multiplexer as the main body, combined with the wavelength independence of scattering, can realize simultaneous linewidth compression of multiple optical signals of different wavelengths.

由上述实施例可见，本发明通过采用散射原理与密集型波分复用器结合，实现了单个线宽压缩***对多波长激光线宽的同时压缩，实现了整体***更高的集成度、更好的稳定性和更广的结构扩展性；本发明利用向后散射为激光谐振腔提供回馈信号，具有波长无关性，可以实现一个压缩***对任意波长激光的线宽压缩；本发明利用所述累积光纤在激光振荡过程中回馈相比于原始注入信号更窄的信号来实现对线宽的深压缩，最终获得超窄线宽激光输出。It can be seen from the above embodiments that the present invention realizes the simultaneous compression of multi-wavelength laser linewidth by a single linewidth compression system by combining the scattering principle with the dense wavelength division multiplexer, thereby achieving higher integration and better integration of the overall system. Good stability and wider structural scalability; the present invention uses backscattering to provide feedback signals for the laser resonator, which is wavelength-independent, and can realize a compression system to compress the linewidth of lasers of any wavelength; the present invention uses the In the laser oscillation process, the cumulative fiber feeds back a signal that is narrower than the original injected signal to achieve deep compression of the line width, and finally obtain an ultra-narrow line width laser output.

需要注意的是：所述散射回馈结构包含常规单模光纤，大数值空间光纤，多模光纤等任意能在内部形成散射的光波导结构或其他结构。所述激光阵列波长的选择可覆盖激光任意波段，该发明所采用的线宽压缩机制不具波长的选择性。本专利所提供的技术对半导体激光器类型和光纤激光器类型的激光器都适用。另外，如果一个激光发生增益装置因环境温度变化，外界震动等因素使得生成的光信号的波长产生严重的漂移，那么当光信号被传输至第一密集型波分复用器时，第一密集型波分复用器无法接收该波长的光进行合束，因而这要求激光发生增益装置本身要足够稳定。本发明对所述激光发生增益装置以及其他装置的抗温度变化和抗震动进行了适应性配置，以保证第一密集型波分复用器能够准确接收来自所述激光发生增益装置的信号，并保证第二密集型波分复用器的最尾端输出的光信号足够稳定。It should be noted that the scattering feedback structure includes conventional single-mode optical fibers, large-value spatial optical fibers, multi-mode optical fibers, and any other optical waveguide structures or other structures that can form scattering inside. The wavelength of the laser array can be selected to cover any wavelength band of the laser, and the linewidth compression mechanism adopted by the invention does not have wavelength selectivity. The technology provided by this patent is applicable to both semiconductor laser type and fiber laser type lasers. In addition, if a laser gain device has a serious drift in the wavelength of the generated optical signal due to environmental temperature changes, external vibration and other factors, then when the optical signal is transmitted to the first dense wavelength division multiplexer, the first dense The type wavelength division multiplexer cannot receive the light of this wavelength for beam combination, so this requires the laser generating gain device itself to be sufficiently stable. The present invention adapts the anti-temperature change and anti-vibration configuration of the laser generating gain device and other devices to ensure that the first dense wavelength division multiplexer can accurately receive the signal from the laser generating gain device, and Ensure that the optical signal output at the end of the second dense wavelength division multiplexer is sufficiently stable.

实施例3：Example 3:

参见图4，为本发明片上超窄线宽激光器的一个结构示意图。该片上超窄线宽激光器可以包括激光发生增益单元20、分布式散射回馈单元18、第一光准直透镜19和第二光准直透镜21，所述激光发生增益单元20的第一输出端通过所述第一光准直透镜19连接所述分布式散射回馈单元18的第一端，激光发生增益单元的第二输出端连接所述第二光准直透镜21的第一端；所述激光发生增益单元20用于生成宽光谱的初始光信号，并对生成的光信号进行波长选择，获得具有特定波长光信号，所述具有特定波长光信号的一部分通过所述第一光准直透镜19传输给所述分布式散射回馈单元18的第一端，另一部分通过所述第二光准直透镜21输出；所述分布式散射回馈单元18的第一端在接收到具有特定波长光信号后，对该光信号进行线宽压缩，并通过所述第一光准直透镜19将线宽压缩后的后向散射光信号传输给所述激光发生增益单元20，所述激光发生增益单元20在接收到回馈的光信号后，对回馈的光信号进行增益放大，针对增益放大后的光信号，将其一部分通过所述第二光准直透镜21输出，另一部分通过所述第一光准直透镜19再次传输给所述分布式散射回馈单元18的第一端做进一步线宽压缩，当达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元18循环线宽压缩后，获得的单纵模超窄线宽光信号从所述第二光准直透镜21输出。Refer to Fig. 4, which is a schematic diagram of the structure of the on-chip ultra-narrow linewidth laser of the present invention. The on-chip ultra-narrow linewidth laser may include a laser generating gain unit 20, a distributed scattering feedback unit 18, a first light collimating lens 19 and a second light collimating lens 21, and the first output end of the laser generating gain unit 20 The first light collimating lens 19 is connected to the first end of the distributed scattering feedback unit 18, and the second output end of the laser generating gain unit is connected to the first end of the second light collimating lens 21; The laser generating gain unit 20 is used to generate a broad-spectrum initial optical signal, and perform wavelength selection on the generated optical signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength passes through the first optical collimator lens 19 is transmitted to the first end of the distributed scattering feedback unit 18, and the other part is output through the second light collimating lens 21; the first end of the distributed scattering feedback unit 18 receives an optical signal with a specific wavelength After that, line width compression is performed on the optical signal, and the backscattered light signal after the line width compression is transmitted to the laser generating gain unit 20 through the first optical collimator lens 19, and the laser generating gain unit 20 After receiving the feedback optical signal, the feedback optical signal is gain-amplified. For the gain-amplified optical signal, a part of it is output through the second optical collimator lens 21, and the other part is output through the first optical signal. The straight lens 19 is again transmitted to the first end of the distributed scattering feedback unit 18 for further linewidth compression. When reaching a steady state, the optical signal with a specific wavelength passes through the distributed scattering feedback unit 18 to cyclically compress the linewidth. After that, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the second light collimating lens 21.

本实施例中，所述分布式散射回馈单元18包括具有高散射系数的特殊光纤、特殊气体材料制成的波导结构，或者刻写在基底上的特殊散射波导。本发明通过对所述分布式散射回馈单元18的散射系数和信号回馈比例进行调节，可以实现光信号线宽的循环压缩和单纵模输出的调控；该分布式散射回馈单元18包括瑞利散射在内的所有分布式散射机制，分布式散射回馈单元18回馈传输的光信号是一个涵盖瑞利散射特征的分布式散射回馈信号，通过所述分布式散射回馈单元来实现激光波长与有效分布式反馈腔的自匹配。本发明是通过分布式散射回馈单元产生的后向回馈信号来实现激光波长的自腔长匹配和无纵模输出，可以通过设计分布式散射回馈单元的结构来避免其他非线性效应对激光线宽压缩的影响。由于以瑞利散射为代表的分布式散射回馈单元18在激光的每次振荡过程中产生一个频域线宽相比于原始注入信号更窄的后向散射信号并回馈到激光发生增益单元18中进行增益放大，因而本发明能够实现激光线宽的深压缩。In this embodiment, the distributed scattering feedback unit 18 includes a special optical fiber with a high scattering coefficient, a waveguide structure made of a special gas material, or a special scattering waveguide written on a substrate. By adjusting the scattering coefficient and signal feedback ratio of the distributed scattering feedback unit 18, the present invention can realize the cyclic compression of the optical signal line width and the regulation of single longitudinal mode output; the distributed scattering feedback unit 18 includes Rayleigh scattering In all the distributed scattering mechanisms, the optical signal transmitted by the distributed scattering feedback unit 18 is a distributed scattering feedback signal covering the characteristics of Rayleigh scattering, and the laser wavelength and effective distribution are realized through the distributed scattering feedback unit. Self-matching of the feedback cavity. The invention realizes the self-cavity length matching of the laser wavelength and no longitudinal mode output through the backward feedback signal generated by the distributed scattering feedback unit. The structure of the distributed scattering feedback unit can be designed to avoid other nonlinear effects on the laser line width. The impact of compression. Because the distributed scattering feedback unit 18 represented by Rayleigh scattering generates a backscattered signal with a narrower frequency domain linewidth than the original injection signal during each oscillation process of the laser, and feeds it back to the laser generating gain unit 18 Gain amplification is performed, so the present invention can achieve deep compression of the laser linewidth.

所述激光发生增益单元20包括增益介质300和光纤光栅FBG(Fiber Bragg Grating，光纤布拉格光栅)301，所述增益介质300在电激励作用下生成宽光谱的初始光信号，生成的光信号传输给所述FBG 301，所述FBG 301对生成的光信号进行波长选择，获得具有特定波长光信号，所述具有特定波长光信号的一部分通过所述第一光准直透镜19传输给所述分布式散射回馈单元18的第一端，另一部分通过所述第二光准直透镜21输出；所述分布式散射回馈单元18的第一端在接收到具有特定波长光信号，对该光信号进行线宽压缩后，依次通过所述第一光准直透镜19、所述FBG 301将线宽压缩后向后回馈的光信号传输给所述增益介质300，所述增益介质300在接收到回馈的光信号后，对回馈的光信号进行增益放大，针对增益放大后的光信号，将其一部分依次通过所述FBG 301、第二光准直透镜21输出，另一部分依次通过所述FBG 301、第一光准直透镜19再次传输给所述分布式散射回馈单元18的第一端做进一步线宽压缩。其中，所述激光发生增益单元20的增益介质300可覆盖激光增益的任意波段，其不具波长的选择性，适用于任意波段和任意类型激光线宽的深压缩。该增益介质300可以为线型，该FBG 301可以刻写在线型的增益介质300的下侧，该增益介质300通过其下侧与该FBG 301进行光信号交互，该FBG 301的左端作为该激光发生增益单元的3的第一输出端，右端作为该激光发生增益单元20的第二输出端。The laser generating gain unit 20 includes a gain medium 300 and a fiber Bragg grating (FBG) 301. The gain medium 300 generates a broad-spectrum initial optical signal under electrical excitation, and the generated optical signal is transmitted to The FBG 301 and the FBG 301 perform wavelength selection on the generated optical signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength is transmitted to the distributed optical signal through the first optical collimator lens 19 The first end of the scattering feedback unit 18, and the other part is output through the second light collimating lens 21; the first end of the distributed scattering feedback unit 18 receives an optical signal with a specific wavelength, and performs a line on the optical signal. After the wide compression, the optical signal fed back after the line width compression is transmitted to the gain medium 300 through the first optical collimator lens 19 and the FBG 301 in turn, and the gain medium 300 receives the returned light After the signal, the feedback optical signal is gain-amplified. For the gain-amplified optical signal, a part of it is output through the FBG 301 and the second optical collimator lens 21 in turn, and the other part is output through the FBG 301 and the first optical signal in turn. The light collimating lens 19 is again transmitted to the first end of the distributed scattering feedback unit 18 for further line width compression. Wherein, the gain medium 300 of the laser generating gain unit 20 can cover any wavelength band of laser gain, it has no wavelength selectivity, and is suitable for deep compression of any wavelength band and any type of laser linewidth. The gain medium 300 can be linear, and the FBG 301 can be written on the lower side of the linear gain medium 300. The gain medium 300 interacts with the FBG 301 through the lower side of the optical signal, and the left end of the FBG 301 serves as the laser generator. The first output end of the gain unit 3 and the right end are used as the second output end of the laser generating gain unit 20.

由上述实施例可见，本发明设置有激光发生增益单元、分布式散射回馈单元、第一光准直透镜和第二光准直透镜，在将光信号传输给分布式散射回馈单元进行循环线宽压缩之前，激光发生增益单元首先选择出具有特定波长光信号，然后将具有特定波长光信号传输给分布式散射回馈单元进行循环线宽压缩，由此可以提高压缩效率；本发明通过分布式散射回馈单元来实现输出波长与有效反馈腔的自匹配，从而可以在实现模式选择的同时实现激光线宽的深压缩，获得边模抑制比较高的单纵模输出，并且整个激光器结构简单、体积较小。It can be seen from the above embodiments that the present invention is provided with a laser generating gain unit, a distributed scattering feedback unit, a first light collimating lens and a second light collimating lens, and the optical signal is transmitted to the distributed scattering feedback unit for circulating line width. Before compression, the laser generating gain unit first selects an optical signal with a specific wavelength, and then transmits the optical signal with a specific wavelength to the distributed scattering feedback unit for cyclic linewidth compression, thereby improving the compression efficiency; the present invention uses distributed scattering feedback The unit realizes the self-matching of the output wavelength and the effective feedback cavity, which can realize the deep compression of the laser linewidth while realizing the mode selection, and obtain the single longitudinal mode output with relatively high side mode suppression, and the entire laser has a simple structure and a small volume .

另外，本发明片上超窄线宽激光器还可以包括第一光隔离器22，结合图4所示，所述第二光准直透镜21的第二端连接所述第一光隔离器22。片上超窄线宽激光器还可以还包括第二光隔离器22，结合图5所示，所述分布式散射回馈单元18的第二端连接所述第二光隔离器22，所述分布式散射回馈单元18的第一端在接收到光信号，对该光信号进行线宽压缩后，通过所述第二光隔离器22将线宽压缩后向前传输的光信号输出；当达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元18循环线宽压缩后，获得的单纵模超窄线宽光信号从所述第二光隔离器22输出。本发明通过将第二光准直透镜的第二端连接所述第一光隔离器或者将分布式散射回馈单元的第二端连接所述第二光隔离器，可以实现单纵模超窄线宽光信号的单端稳定输出。当然，当第二光准直透镜21的第二端连接所述第一光隔离器22，并且分布式散射回馈单元18的第二端连接所述第二光隔离器22时，可以实现单纵模超窄线宽光信号的双端稳定输出。In addition, the on-chip ultra-narrow linewidth laser of the present invention may further include a first optical isolator 22. As shown in FIG. 4, the second end of the second optical collimator lens 21 is connected to the first optical isolator 22. The on-chip ultra-narrow linewidth laser may further include a second optical isolator 22. As shown in FIG. 5, the second end of the distributed scattering feedback unit 18 is connected to the second optical isolator 22, and the distributed scattering feedback unit 18 is connected to the second optical isolator 22. After the first end of the feedback unit 18 receives the optical signal and compresses the line width of the optical signal, the second optical isolator 22 compresses the line width and then outputs the optical signal transmitted forward; when it reaches a steady state After the optical signal with the specific wavelength is compressed by the distributed scattering feedback unit 18 cyclic linewidth compression, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the second optical isolator 22. In the present invention, by connecting the second end of the second optical collimating lens to the first optical isolator or connecting the second end of the distributed scattering feedback unit to the second optical isolator, a single longitudinal mode ultra-narrow line can be realized Single-ended stable output of wide optical signal. Of course, when the second end of the second optical collimating lens 21 is connected to the first optical isolator 22, and the second end of the distributed scattering feedback unit 18 is connected to the second optical isolator 22, a single longitudinal direction can be realized. The dual-ended stable output of the optical signal of the mode ultra-narrow line width.

由于本发明激光器结构简单、体积较小，因此在实现激光器集成化、芯片化的进程中，本发明尤其适用，其中所述激光发生增益单元20、分布式散射回馈单元18、第一光准直透镜19、第二光准直透镜21、第一光隔离器和第二光隔离器中至少激光发生增益单元20、分布式散射回馈单元1、第一光准直透镜19和第二光准直透镜21集成在基板上。Due to the simple structure and small volume of the laser of the present invention, the present invention is particularly suitable in the process of realizing laser integration and chipization. The laser generating gain unit 20, the distributed scattering feedback unit 18, and the first light collimator are particularly suitable. Among the lens 19, the second optical collimator lens 21, the first optical isolator and the second optical isolator, at least the laser generation gain unit 20, the distributed scattering feedback unit 1, the first optical collimator lens 19 and the second optical collimator The lens 21 is integrated on the substrate.

本发明中以瑞利散射为代表的瑞利散射单元实现激光线宽深压缩为例，其原理可解释为：In the present invention, the Rayleigh scattering unit represented by Rayleigh scattering realizes the deep compression of laser linewidth as an example, and the principle can be explained as follows:

其中：

表示在第k次激光振荡过程中输出的信号谱，

表示第k-1次回馈到激光增益介质中的分布式回馈信号，FRBS表示以瑞利散射为代表的分布式对每次注入信号的线宽衰减因子，可表示为： among them:

Represents the output signal spectrum during the k-th laser oscillation process,

Represents the distributed feedback signal fed back into the laser gain medium for the k-1th time. FRBS represents the linewidth attenuation factor of the distributed signal for each injection represented by Rayleigh scattering, which can be expressed as:

由于此过程属于一个线性散射过程，因此线宽衰减FRBS是一个常数。在激光振荡过程中，由于瑞利散射单元对每次注入的激光线宽的线宽都是以一定的比例压缩后再次回馈到增益单元中进行放大。类似周而复始的循环，线宽在激光到达动态平衡时将得到深压缩。Since this process is a linear scattering process, the line width attenuation FRBS is a constant. During the laser oscillation process, because the Rayleigh scattering unit compresses the line width of the laser line width injected each time by a certain ratio, it is fed back to the gain unit for amplification again. Similar to the repeated cycle, the line width will be deeply compressed when the laser reaches the dynamic equilibrium.

需要注意的是：分布式散射回馈单元是集成于激光芯片上的高散射系数的材料，其可以是具有高散射系数的特殊光纤(Fiber)、特殊气体材料，或利用飞秒加工等技术写在芯片上的特殊散射波导。激光发生增益单元的增益介质所应有的激光波段可覆盖激光任意波段，该发明在线宽激光线宽深压缩和模式选择上不具有波长的选择性。所述的光学器件可以是光纤连接，也可以是空间耦合连接。另外，不论所述激光增益单元是半导体类型还是光纤激光增益类型，利用该方法都能将激光输出线宽压缩至Hz量级。It should be noted that the distributed scattering feedback unit is a material with high scattering coefficient integrated on the laser chip. It can be a special optical fiber with high scattering coefficient (Fiber), a special gas material, or the use of femtosecond processing technology. Special scattering waveguide on the chip. The laser wavelength band of the gain medium of the laser generating gain unit can cover any wavelength band of the laser. The invention does not have wavelength selectivity in terms of linewidth laser linewidth deep compression and mode selection. The optical device can be optical fiber connection or spatial coupling connection. In addition, regardless of whether the laser gain unit is of a semiconductor type or a fiber laser gain type, the laser output linewidth can be compressed to the order of Hz by this method.

实施例4：Example 4:

参见图6，为本发明可调谐超窄线宽激光器的一个实施例结构示意图。该可调谐超窄线宽激光器可以包括激光生成增益单元12、分布式散射回馈单元14、第一光准直透镜13、第第二光准直透镜15和可调谐滤波单元16，所述激光生成增益单元12的第一输出端和第二输出端对应设置有第一薄膜1200和第二薄膜1201，所述第一薄膜1200和第二薄膜1201都具有透射和反射特性，所述激光生成增益单元12的第一输出端依次通过所述第一薄膜1200、第一光准直透镜13连接所述分布式散射回馈单元14的第一端，激光发生增益单元的第二输出端依次通过所述第二薄膜1201、第二光准直透镜15连接所述可调谐滤波单元16；所述激光生成增益单元12用于生成宽光谱的初始激光信号并分别传输给所述第一薄膜1200和第二薄膜1201，所述第一薄膜1200在接收到光信号后，将一部分反射给所述激光生成增益单元12，另一部分通过所述第一光准直透镜13传输给所述分布式散射回馈单元14；所述第二薄膜1201在接收到光信号后，将一部分反射给所述激光生成增益单元12，另一部分通过所述第二光准直透镜21第二光准直透镜15传输给所述可调谐滤波单元16；所述可调谐滤波单元16在接收到激光信号后，对初始激光信号进行波长选择和调谐，获得具有可调谐特性的具有特定波长光信号，所述具有可调谐特性的具有特定波长光信号一部分通过所述第二光准直透镜15和所述第二薄膜1201传输至激光发生增益单元，另一部分直接输出；所述分布式散射回馈单元14的第一端在接收到光信号后，对该光信号进行线宽压缩，并通过所述第一光准直透镜13将线宽压缩后向后回馈的光信号传输给所述第一薄膜1200；所述激光生成增益单元12在接收到光信号后，对该光信号进行增益放大，并将增益放大后的光信号再次分别传输给所述第一薄膜1200和第二薄膜1201；在达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元14循环线宽压缩后，获得的单纵模超窄线宽光信号从所述可调谐滤波单元16的另一端通过一个光隔离器17输出。Refer to Fig. 6, which is a schematic structural diagram of an embodiment of the tunable ultra-narrow linewidth laser of the present invention. The tunable ultra-narrow linewidth laser may include a laser generating gain unit 12, a distributed scattering feedback unit 14, a first optical collimating lens 13, a second optical collimating lens 15, and a tunable filter unit 16. The first output end and the second output end of the gain unit 12 are correspondingly provided with a first film 1200 and a second film 1201, the first film 1200 and the second film 1201 both have transmission and reflection characteristics, and the laser generates the gain unit The first output end of 12 is connected to the first end of the distributed scattering feedback unit 14 through the first film 1200 and the first light collimator lens 13 in sequence, and the second output end of the laser generating gain unit passes through the first end in sequence. The two thin films 1201 and the second light collimating lens 15 are connected to the tunable filter unit 16; the laser generating gain unit 12 is used to generate a broad-spectrum initial laser signal and transmit it to the first thin film 1200 and the second thin film respectively 1201. After receiving the optical signal, the first film 1200 reflects a part to the laser generating gain unit 12, and the other part is transmitted to the distributed scattering feedback unit 14 through the first optical collimator lens 13; After the second film 1201 receives the optical signal, it reflects a part to the laser generating gain unit 12, and the other part is transmitted to the tunable through the second optical collimator lens 21 and the second optical collimator lens 15. Filter unit 16; after receiving the laser signal, the tunable filter unit 16 performs wavelength selection and tuning on the initial laser signal to obtain a tunable optical signal with a specific wavelength, and the tunable optical signal with a specific wavelength A part of the optical signal is transmitted to the laser generating gain unit through the second optical collimator lens 15 and the second film 1201, and the other part is directly output; the first end of the distributed scattering feedback unit 14 receives the optical signal , Performing line width compression on the optical signal, and transmitting the optical signal fed back after the line width compression to the first film 1200 through the first optical collimator lens 13; the laser generating gain unit 12 is receiving After the optical signal is received, the optical signal is gain-amplified, and the gain-amplified optical signal is again transmitted to the first film 1200 and the second film 1201 respectively; when it reaches a steady state, the optical signal with a specific wavelength After cyclic linewidth compression by the distributed scattering feedback unit 14, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the other end of the tunable filter unit 16 through an optical isolator 17.

由上述实施例可见，本发明在激光生成增益单元的两个输出端处对应设置(例如涂覆)有第一薄膜和第二薄膜，将激光生成增益单元的第一输出端依次通过第一薄膜、第一光准直透镜连接分布式散射回馈单元，将激光发生增益单元的第二输出端依次通过第二薄膜、第二光准直透镜连接可调谐滤波元件，使第一薄膜和第二薄膜都具有透射和反射特性，激光生成增益单元在激光振荡过程中对光信号做循环增益放大，可调节滤波元件对生成的光信号进行波长的选择与调谐，以获得具有可调谐特性的特定波长，分布式散射回馈单元对光信号做循环线宽压缩，激光生成增益单元生成的光信号基于上述路径进行传输，可以实现激光波长调谐过程中线宽深压缩的需求；本发明中的可调谐滤波元件，在接收到光信号后，首先选择出具有特定波长光信号，然后将选择出的特定波长光信号通过第二光准直透镜部分返回给分布式散射回馈单元，使分布式散射回馈单元仅针对该具有特定波长光信号进行线宽压缩，激光生成增益单元仅针对具有特定波长光信号进行增益放大；当可调谐滤波元件选择另一个激光波长时，具有该波长的光信号基于所述光路径进行传输时，分布式散射回馈单元就针对该波长的光信号进行线宽压缩，从而实现了波长调谐过程中激光信号线宽的压缩。本发明通过分布式散射回馈单元的循环压缩，实现了波长调谐过过程中激光线宽的深压缩，获得边模抑制比较高的超窄线宽光信号，相比于常规设计结构更加简单。It can be seen from the above embodiments that the present invention is provided with (for example, coated) a first film and a second film corresponding to the two output ends of the laser generating gain unit, and the first output end of the laser generating gain unit passes through the first film in turn. , The first light collimating lens is connected to the distributed scattering feedback unit, and the second output end of the laser generating gain unit is connected to the tunable filter element through the second film and the second light collimating lens in turn, so that the first film and the second film Both have transmission and reflection characteristics. The laser generating gain unit performs cyclic gain amplification on the optical signal during the laser oscillation process, and the adjustable filter element selects and tunes the wavelength of the generated optical signal to obtain a specific wavelength with tunable characteristics. The distributed scattering feedback unit performs cyclic linewidth compression on the optical signal, and the optical signal generated by the laser generating gain unit is transmitted based on the above path, which can realize the demand for linewidth deep compression in the laser wavelength tuning process; the tunable filter element in the present invention, After receiving the optical signal, first select the optical signal with a specific wavelength, and then return the selected optical signal with a specific wavelength to the distributed scattering feedback unit through the second optical collimating lens part, so that the distributed scattering feedback unit is only for the The optical signal with a specific wavelength performs linewidth compression, and the laser generating gain unit only performs gain amplification for the optical signal with a specific wavelength; when the tunable filter element selects another laser wavelength, the optical signal with this wavelength is transmitted based on the optical path At this time, the distributed scattering feedback unit performs linewidth compression for the optical signal of this wavelength, thereby achieving the compression of the laser signal linewidth during the wavelength tuning process. The invention realizes the deep compression of the laser linewidth during the wavelength tuning process through the cyclic compression of the distributed scattering feedback unit, and obtains an ultra-narrow linewidth optical signal with relatively high side mode suppression, which is simpler than the conventional design structure.

由于本发明激光器的结构简单，因而在实现激光器集成化、芯片化的进程中，本发明尤其适用。另外，所述分布式散射回馈单元14的第一端在接收到光信号后，还通过分布式散射回馈单元的第二端将线宽压缩后向前传输的光信号输出。Due to the simple structure of the laser of the present invention, the present invention is particularly suitable in the process of realizing the integration and chipization of the laser. In addition, after the first end of the distributed scattering feedback unit 14 receives the optical signal, the second end of the distributed scattering feedback unit also compresses the line width and outputs the optical signal transmitted forward.

参见图7，为本发明可调谐超窄线宽激光器的另一实施例结构示意图。该可调谐超窄线宽激光器可以包括激光生成增益单元12、分布式散射回馈单元14、第一光准直透镜19第一光准直透镜13、第二光准直透镜21第二光准直透镜15和可调谐滤波单元16，所述激光生成增益单元12的第一输出端和第二输出端对应设置有第一薄膜1200和第二薄膜1201，所述第一薄膜1200具有透射和反射特性，所述第二薄膜1201具有反射特性，所述激光生成增益单元12的第一输出端依次通过所述第一薄膜1200、第一光准直透镜19第一光准直透镜13连接所述分布式散射回馈单元14的第一端，激光发生增益单元的第二输出端连接所述第二薄膜1201，所述分布式散射回馈单元14的第二端连接所述可调谐滤波单元16；所述激光生成增益单元12用于生成宽光谱的初始激光信号并分别传输给所述第一薄膜1200和第二薄膜1201，所述第一薄膜1200在接收到光信号后，将一部分传输给所述激光生成增益单元12，另一部分通过所述第一光准直透镜19第一光准直透镜13传输给所述分布式散射回馈单元14的第一端；所述第二薄膜1201在接收到光信号后，将所述光信号传输给所述激光生成增益单元12；Refer to FIG. 7, which is a schematic structural diagram of another embodiment of the tunable ultra-narrow linewidth laser of the present invention. The tunable ultra-narrow linewidth laser may include a laser generating gain unit 12, a distributed scattering feedback unit 14, a first light collimating lens 19, a first light collimating lens 13, a second light collimating lens 21, and a second light collimating unit. The lens 15 and the tunable filter unit 16, the first output end and the second output end of the laser generating gain unit 12 are correspondingly provided with a first film 1200 and a second film 1201, and the first film 1200 has transmission and reflection characteristics , The second film 1201 has reflection characteristics, and the first output end of the laser generating gain unit 12 is connected to the distribution through the first film 1200, the first light collimating lens 19, and the first light collimating lens 13 in sequence. The first end of the distributed scattering feedback unit 14, the second output end of the laser generating gain unit is connected to the second film 1201, and the second end of the distributed scattering feedback unit 14 is connected to the tunable filter unit 16; The laser generating gain unit 12 is used to generate a broad-spectrum initial laser signal and transmit it to the first thin film 1200 and the second thin film 1201 respectively. After receiving the light signal, the first thin film 1200 transmits a part to the laser The gain unit 12 is generated, and the other part is transmitted to the first end of the distributed scattering feedback unit 14 through the first light collimating lens 19 and the first light collimating lens 13; the second film 1201 is receiving the optical signal After that, the optical signal is transmitted to the laser generating gain unit 12;

所述激光生成增益单元12在接收到光信号后，对该光信号进行增益放大，并将增益放大后的光信号再次分别传输给所述第一薄膜1200和第二薄膜1201。After receiving the optical signal, the laser generating gain unit 12 performs gain amplification on the optical signal, and transmits the amplified optical signal to the first film 1200 and the second film 1201 respectively.

所述分布式散射回馈单元14的第一端在接收到光信号后，对该光信号进行线宽压缩，并通过所述第一光准直透镜19第一光准直透镜13将线宽压缩后向后回馈的光信号传输给所述第一薄膜1200，将线宽压缩后向前传输的光信号传输给所述可调谐滤波单元16；所述可调谐滤波单元16在接收到激光信号后，对初始激光信号进行波长选择和调谐，获得具有特定波长光信号，所述具有特定波长光信号一部分传输给所述分布式散射回馈单元14的第二端，另一部分直接输出；所述分布式散射回馈单元14的第二端在接收到所述具有特定波长光信号后，对该光信号进行线宽压缩，并通过所述第一光准直透镜19第一光准直透镜13将线宽压缩后向前传输的光信号传输给所述第一薄膜1200，将线宽压缩后向后回馈的光信号传输给所述可调谐滤波单元16；在达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元14循环线宽压缩后，获得的单纵模超窄线宽光信号从所述可调谐滤波单元16输出。After receiving the optical signal, the first end of the distributed scattering feedback unit 14 performs line width compression on the optical signal, and compresses the line width through the first light collimating lens 19 and the first light collimating lens 13 The optical signal fed back backward is transmitted to the first film 1200, and the optical signal transmitted forward after the line width is compressed is transmitted to the tunable filter unit 16; after the tunable filter unit 16 receives the laser signal , Performing wavelength selection and tuning on the initial laser signal to obtain an optical signal with a specific wavelength, a part of the optical signal with a specific wavelength is transmitted to the second end of the distributed scattering feedback unit 14, and the other part is directly output; After receiving the optical signal with a specific wavelength, the second end of the scattering feedback unit 14 performs line width compression on the optical signal, and passes the first optical collimator lens 19 and the first optical collimator lens 13 to reduce the line width. The optical signal transmitted forward after compression is transmitted to the first thin film 1200, and the optical signal returned after the line width is compressed is transmitted to the tunable filter unit 16; when the steady state is reached, the light with a specific wavelength After the signal is cyclically compressed by the distributed scattering feedback unit 14, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the tunable filter unit 16.

同样地，由上述实施例可见，本发明在激光生成增益单元的两个输出端处对应设置有第一薄膜和第二薄膜，将激光生成增益单元的第一输出端依次通过第一薄膜、第一光准直透镜连接分布式散射回馈单元，将激光生成增益单元的第二输出端连接第二薄膜，使第一薄膜具有透射和反射特性，第二薄膜具有反射特性，激光生成增益单元对光信号做循环增益放大，分布式散射回馈单元对光信号做循环线宽压缩，可调谐滤波元件对光信号进行波长的选择与调谐，激光生成增益单元生成的光信号基于上述路径进行传输，可以实现激光波长调谐过程中线宽的深压缩，以便满足不同激光波长线宽压缩的需求；通过对激光生成增益单元、分布式散射回馈单元、第一薄膜和第二薄膜之间的位置关系进行设计，可以使线宽压缩后的光信号在被输出之前得到充分的增益放大，从而可以大大降低装置能耗。Similarly, it can be seen from the above embodiments that the present invention is provided with a first film and a second film corresponding to the two output ends of the laser generating gain unit, and the first output end of the laser generating gain unit passes through the first film and the second film in sequence. A light collimating lens is connected to the distributed scattering feedback unit, and the second output end of the laser generating gain unit is connected to the second film, so that the first film has transmission and reflection characteristics, and the second film has reflection characteristics. The laser generating gain unit faces the light The signal is amplified by cyclic gain, the distributed scattering feedback unit performs cyclic linewidth compression on the optical signal, the tunable filter element selects and tunes the wavelength of the optical signal, and the optical signal generated by the laser generating gain unit is transmitted based on the above path, which can be realized The deep compression of the linewidth in the laser wavelength tuning process to meet the needs of different laser wavelength linewidth compression; by designing the positional relationship between the laser generating gain unit, the distributed scattering feedback unit, the first film and the second film, you can The optical signal after the linewidth compression is fully amplified before being output, which can greatly reduce the energy consumption of the device.

本发明中的可调谐滤波元件，在光信号进行循环压缩之前，首先选择出具有特定波长光信号，然后将选择出的特定波长光信号返回给分布式散射回馈单元，使分布式散射回馈单元仅针对该具有特定波长光信号进行线宽压缩，激光生成增益单元仅针对具有特定波长光信号进行增益放大。当可调谐滤波元件调谐到另一个激光波长时，具有该波长的光信号基于所述光路径进行传输时，分布式散射回馈单元就针对该波长的光信号进行线宽压缩，从而实现了波长调谐过程中激光信号线宽的压缩。本发明通过分布式散射回馈单元的循环压缩，实现了不同调谐波长激光线宽的深压缩，获得边模抑制比较高的超窄线宽光信号，相比于常规设计结构更加简单。The tunable filter element in the present invention first selects an optical signal with a specific wavelength before the optical signal is cyclically compressed, and then returns the selected specific wavelength optical signal to the distributed scattering feedback unit, so that the distributed scattering feedback unit is only The line width compression is performed on the optical signal with a specific wavelength, and the laser generating gain unit only performs gain amplification on the optical signal with the specific wavelength. When the tunable filter element is tuned to another laser wavelength, when the optical signal with this wavelength is transmitted based on the optical path, the distributed scattering feedback unit performs linewidth compression for the optical signal of this wavelength, thereby achieving wavelength tuning The compression of the laser signal line width in the process. Through the cyclic compression of the distributed scattering feedback unit, the present invention realizes the deep compression of laser linewidths of different tuning wavelengths, and obtains ultra-narrow linewidth optical signals with relatively high side mode suppression, which is simpler than the conventional design structure.

由于本发明激光器的结构简单，因而在实现激光器集成化、芯片化的进程中，本发明尤其适用。另外，所述第二薄膜1201还可以具有透射特性，所述第二薄膜1201还与第二光准直透镜21第二光准直透镜15连接，所述第二薄膜1201在接收到光信号后，将所述光信号的一部分传输给所述激光生成增益单元12，另一部分通过所述第二光准直透镜21第二光准直透镜15输出，由此可以实现双端输出。Due to the simple structure of the laser of the present invention, the present invention is particularly suitable in the process of realizing the integration and chipization of the laser. In addition, the second film 1201 may also have transmission characteristics. The second film 1201 is also connected to the second light collimating lens 21 and the second light collimating lens 15. After the second film 1201 receives the optical signal, , A part of the optical signal is transmitted to the laser generating gain unit 12, and the other part is output through the second light collimating lens 21 and the second light collimating lens 15, so that a double-ended output can be realized.

结合上述实施例中，为了实现单纵模超窄线宽光信号的稳定输出，本发明可调谐超窄线宽激光器还可以包括光隔离器，所述可调谐滤波元件与所述光隔离器连接，用于通过所述光隔离器将获得的单纵模超窄线宽光信号输出。所述分布式散射回馈单元14包括具有高散射系数的特殊光纤、特殊气体材料制成的波导结构，或者是(利用飞秒等技术)刻写在基板上的特殊散射波导。分布式散射回馈单元是基于分布式反馈效应进行线宽压缩的一种单元，无论是其第一端，还是第二端，其在接收到光信号后，光信号都会被进行线宽压缩，线宽压缩后的光信号一部分从光信号接收端反馈传输回去，另一部分从另一端传输出去。本发明通过所述分布式散射回馈单元来实现激光波长与有效分布式散射腔的自匹配；所述分布式散射回馈单元是包括瑞利散射在内的所有分布式散射机制，通过分布式散射回馈单元中有效反馈腔对激光波长的自匹配特性来实现激光的单纵模输出。本发明通过对所述分布式散射回馈单元14的散射系数和信号回馈比例进行调节，可以实现光信号线宽的压缩调节，从而可以对输出光信号的线宽进行调控。具体地，由于光信号每次被传输给分布式散射回馈单元14，都会被分布式散射回馈单元14进行一次线宽压缩，通过对分布式散射回馈单元的散射系数进行调节，可以对每次压缩的线宽进行调节。In combination with the above embodiments, in order to achieve a stable output of a single longitudinal mode ultra-narrow linewidth optical signal, the tunable ultra-narrow linewidth laser of the present invention may further include an optical isolator, and the tunable filter element is connected to the optical isolator , For outputting the obtained single longitudinal mode ultra-narrow linewidth optical signal through the optical isolator. The distributed scattering feedback unit 14 includes a special optical fiber with a high scattering coefficient, a waveguide structure made of a special gas material, or a special scattering waveguide (using femtosecond and other technologies) written on a substrate. The distributed scattering feedback unit is a unit that performs linewidth compression based on the distributed feedback effect. Whether it is the first end or the second end, after receiving the optical signal, the optical signal will be compressed by the linewidth. After the wide compression, a part of the optical signal is fed back from the optical signal receiving end, and the other part is transmitted from the other end. The present invention uses the distributed scattering feedback unit to realize the self-matching of the laser wavelength and the effective distributed scattering cavity; the distributed scattering feedback unit is all distributed scattering mechanisms including Rayleigh scattering, through distributed scattering feedback The unit effectively feedbacks the self-matching characteristics of the cavity to the laser wavelength to realize the single longitudinal mode output of the laser. In the present invention, by adjusting the scattering coefficient and the signal feedback ratio of the distributed scattering feedback unit 14, the line width of the optical signal can be compressed and adjusted, so that the line width of the output optical signal can be adjusted. Specifically, since each optical signal is transmitted to the distributed scattering feedback unit 14, it will be compressed by the distributed scattering feedback unit 14. By adjusting the scattering coefficient of the distributed scattering feedback unit, each compression can be performed. The line width is adjusted.

结合上述实施例中，所述激光生成增益单元12可以包括增益介质1202，所述增益介质1202在电激励下生成宽光谱的初始光信号并将生成的光信号分别传输给所述第一薄膜1200和第二薄膜1201，在接收到光信号后，对该光信号进行增益放大(例如对光功率进行增益放大)，并将增益放大后的光信号再次分别传输给所述第一薄膜1200和第二薄膜1201。激光生成增益单元可覆盖激光增益的任意波段，该压缩机制不具波长的选择性，适用于任意波段和任意类型激光线宽的深压缩。In combination with the foregoing embodiment, the laser generating gain unit 12 may include a gain medium 1202, which generates a broad-spectrum initial optical signal under electrical excitation and transmits the generated optical signal to the first thin film 1200. And the second film 1201, after receiving the optical signal, the optical signal is gain-amplified (for example, the optical power is gain-amplified), and the gain-amplified optical signal is again transmitted to the first film 1200 and the first film 1200 and the second film, respectively. Two film 1201. The laser generating gain unit can cover any band of laser gain. This compression mechanism does not have wavelength selectivity and is suitable for deep compression of any band and any type of laser linewidth.

上述实施例在实现激光器集成化、芯片化的进程中，所述激光生成增益单元12、分布式散射回馈单元14、第一光准直透镜19第一光准直透镜13、第二光准直透镜21第二光准直透镜15和可调谐滤波单元16中至少所述激光生成增益单元12、分布式散射回馈单元14和第一光准直透镜19第一光准直透镜13集成在基板上。本发明通过将各个组件集成于基板上，可以实现集成化，提高***稳定性。In the above embodiment, in the process of realizing laser integration and chipization, the laser generating gain unit 12, the distributed scattering feedback unit 14, the first light collimating lens 19, the first light collimating lens 13, and the second light collimating unit In the lens 21, at least the laser generating gain unit 12, the distributed scattering feedback unit 14, and the first light collimating lens 19 among the second light collimating lens 15 and the tunable filter unit 16 are integrated on the substrate. . The present invention can realize integration and improve the stability of the system by integrating various components on the substrate.

其中，所述可调谐滤波单元16可以为闪耀光栅Grating，结合图1所示，该闪耀光栅可以沿着第二光准直透镜21第二光准直透镜15的光信号输出方向，呈对应预设角度(例如450)设置，以使该闪耀光栅在接收到第二光准直透镜21第二光准直透镜15输出的光信号后，将其中对应预设波长光信号垂直于其输入方向调谐输出。本发明可以通过调控闪耀光栅的参数(例如波长、调谐精度，调谐范围等)来对光信号进行波长选择和调谐，当然，可调谐滤波器也可以包含基于声光、热光以及其他调谐机制的器件。所述分布式散射回馈单元可以包含具有高散射系数的所有介质波导，其可以是具有高散射系数的特殊光纤(Fiber)、特殊气体材料，或利用飞秒加工等技术写在芯片上的特殊散射波导。所述激光增益单元的增益谱可覆盖激光任意波段，该发明在激光波长调谐的线宽深压缩中不具波长的选择性。另外，本专利所提供的技术对半导体类型和光纤激光增益类型的激光器都适用。Wherein, the tunable filter unit 16 may be a blazed grating Grating, as shown in FIG. Set the angle (for example, 450) so that the blazed grating will tune the optical signal corresponding to the preset wavelength perpendicular to its input direction after receiving the optical signal output by the second optical collimator lens 21 and the second optical collimator lens 15. Output. The present invention can select and tune the wavelength of the optical signal by adjusting the parameters of the blazed grating (such as wavelength, tuning accuracy, tuning range, etc.). Of course, the tunable filter can also include acousto-optic, thermo-optical and other tuning mechanisms. Device. The distributed scattering feedback unit may include all dielectric waveguides with high scattering coefficients, which may be special optical fibers with high scattering coefficients (Fiber), special gas materials, or special scattering written on the chip using femtosecond processing techniques. waveguide. The gain spectrum of the laser gain unit can cover any wavelength band of the laser, and this invention does not have wavelength selectivity in the linewidth deep compression of laser wavelength tuning. In addition, the technology provided by this patent is applicable to both semiconductor type and fiber laser gain type lasers.

以上各实施例仅用以说明本发明的技术方案，而非对其限制；尽管参照前述各实施例对本发明进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分或者全部技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本发明各实施例技术方案的范围，其均应涵盖在本发明的权利要求和说明书的范围当中。The above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still implement the foregoing various embodiments. The technical solutions recorded in the examples are modified, or some or all of the technical features are equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all cover Within the scope of the claims and specification of the present invention.

Claims

一种激光深压缩方法，其特征在于，包括以下步骤：A laser deep compression method is characterized in that it comprises the following steps:

1)激光发生增益单元发出激光信号；1) The laser generating gain unit sends out the laser signal;

2)发出的激光信号经过分布式散射回馈单元，所述激光信号的一部分输出，所述激光信号的其余部分回馈到所述激光发生增益单元；2) The emitted laser signal passes through the distributed scattering feedback unit, a part of the laser signal is output, and the rest of the laser signal is fed back to the laser generation gain unit;

3)所述激光发生增益单元接收到回馈的所述其余部分，对其进行增益后再次发出至所述分布式散射回馈单元。3) The laser generating gain unit receives the remaining part of the feedback, gains it, and sends it to the distributed scattering feedback unit again.
一种激光器，其特征在于：包括激光发生增益单元、分布式散射回馈单元；A laser, characterized in that it comprises a laser generating gain unit and a distributed scattering feedback unit;

所述激光发生增益单元，用于产生初始激光信号，并对从所述分布式散射回馈单元接受的后向散射回馈信号进行增益放大，并将经所述增益放大后的所述后向散射回馈信号再次传输至所述分布式散射回馈单元；The laser generating gain unit is configured to generate an initial laser signal, and perform gain amplification on the backscatter feedback signal received from the distributed scattering feedback unit, and feed back the backscattered feedback signal amplified by the gain The signal is again transmitted to the distributed scattering feedback unit;

所述分布式散射回馈单元，用于当所述初始激光信号经过时产生分布式散射回馈信号，并将所述分布式散射信号中的所述后向散射信号回馈到所述激光发生增益单元实现增益放大。The distributed scattering feedback unit is used to generate a distributed scattering feedback signal when the initial laser signal passes through, and to feed the backscattered signal in the distributed scattering signal back to the laser generating gain unit. Gain amplification.
根据权利要求2所述的激光器，其特征在于：还包括链接所述激光发射增益单元和所述分布式散射回馈单元的透镜结构；3. The laser according to claim 2, further comprising a lens structure linking the laser emission gain unit and the distributed scattering feedback unit;

所述透镜结构包括耦合透镜，半透半反镜片和凸透镜；The lens structure includes a coupling lens, a transflective lens and a convex lens;

所述分布式散射回馈单元包括散射增益介质，以及半球面镜，在所述半球面镜的内侧均匀分布有所述散射增益介质；The distributed scattering feedback unit includes a scattering gain medium and a hemispherical mirror, and the scattering gain medium is uniformly distributed on the inner side of the hemispherical mirror;

其中，所述激光发生增益单元产生所述初始激光后输出到所述耦合透镜，所述初始激光经所述耦合透镜耦合后成为水平传输的空间光；Wherein, the laser generation gain unit generates the initial laser light and outputs it to the coupling lens, and the initial laser light is coupled by the coupling lens to become horizontally transmitted spatial light;

所述空间光传输到所述半透半反镜片，并产生对应的透射光与反射光，其中所述透射光继续传输至所述凸透镜，所述反射光作为输出激光输出；The spatial light is transmitted to the semi-transmissive and semi-reflective lens to generate corresponding transmitted light and reflected light, wherein the transmitted light continues to be transmitted to the convex lens, and the reflected light is output as an output laser;

所述凸透镜接收到所述透射光后，将所述透射光沿着所述凸透镜的凸透面向外沿指定角度分散传输，最终传输至所述半球面镜；After the convex lens receives the transmitted light, the transmitted light is dispersed and transmitted along a specified angle outward along the convex transparent surface of the convex lens, and finally transmitted to the hemispherical mirror;

当从所述凸透镜出射的所述空间光到达所述散射增益介质时，所述空间光在传输过程中会产生较强散射信号；部分所述散射信号能反馈回所述激光发生增益单元。。When the spatial light emitted from the convex lens reaches the scattering gain medium, the spatial light will generate a strong scattering signal during the transmission process; part of the scattering signal can be fed back to the laser generating gain unit. .
根据权利要求3所述的激光器，其特征在于，所述激光发生增益单元接收到来自所述分布式散射回馈单元的所述后向散射回馈信号对其进行增益，以此来实现激光的深度压缩；其中，所述分布式散射回馈装置包含各类能加强散射系数的结构或材料。3. The laser according to claim 3, wherein the laser generation gain unit receives the backscatter feedback signal from the distributed scattering feedback unit to gain gain, so as to achieve deep laser compression ; Wherein, the distributed scattering feedback device includes various structures or materials that can enhance the scattering coefficient.
根据权利要求3所述的激光器，其特征在于，所述分布式散射回馈结构在激光谐振过程中为激光原始产生结构提供散射的较强回馈信号。The laser according to claim 3, wherein the distributed scattering feedback structure provides a strong scattering feedback signal for the original laser generating structure during laser resonance.
根据权利要求3、4或5所述的激光器，其特征在于，将散射原理与所述透镜相结合，实现了在三维空间里对空间激光的超窄线宽压缩。The laser according to claim 3, 4 or 5, wherein the combination of the scattering principle and the lens realizes the ultra-narrow linewidth compression of the spatial laser in the three-dimensional space.
根据权利要求3或4所述的激光器，其特征在于，利用所述散射增益介质产生散射信号的多重反射特性来实现激光的单纵模输出。The laser according to claim 3 or 4, wherein the multiple reflection characteristics of the scattering signal generated by the scattering gain medium are used to realize the single longitudinal mode output of the laser.
根据权利要求4或5所述的激光器，其特征在于，通过替换具有不同散射系数的散射增益介质实现对线宽不同程度的深压缩。The laser according to claim 4 or 5, characterized in that by replacing the scattering gain medium with different scattering coefficients, the deep compression of the line width in different degrees is realized.
根据权利要求3所述的激光器，其特征在于：还包括用于多波长同时的线宽压缩的激光发生增益单元第一密集型波分复用器、光隔离器和第二密集型波分复用器；The laser according to claim 3, characterized in that it further comprises a laser generating gain unit for multi-wavelength simultaneous linewidth compression, a first dense wavelength division multiplexer, an optical isolator, and a second dense wavelength division multiplexer Device

所述激光发生增益单元中包含的每个激光发生增益装置分别连接所述第一密集型波分复用器的对应第一端，所述第一密集型波分复用器的第二端连接所述分布式散射回馈单元的一端；Each laser generating gain device included in the laser generating gain unit is respectively connected to the corresponding first end of the first dense wavelength division multiplexer, and the second end of the first dense wavelength division multiplexer is connected to One end of the distributed scattering feedback unit;

所述分布式散射回馈单元的另一端输出光信号通过所述光隔离器后，再进入与所述光隔离器连接的所述第二密集型波分复用器的第一端；所述分布式散射回馈单元在接收到所述光信号后，基于散射效应，在激光传输过程中产生线宽更窄的后向散射光信号；The optical signal output from the other end of the distributed scattering feedback unit passes through the optical isolator and then enters the first end of the second dense wavelength division multiplexer connected to the optical isolator; the distribution After receiving the optical signal, the scattering feedback unit generates a backscattered optical signal with a narrower line width during the laser transmission process based on the scattering effect;

所述后向散射光信号又传输回所述第一密集型波分复用器的第二端口，所述第一密集型波分复用器的第二端接受到所述后向散射光信号后，又将所述后向散射光信号分成多束不同波长的信号，并将对应波长的所述后向散射光信号从所述第一密集型波分复用器的第一端口的对应通道输出给所述激光发生增益单元激光发生增益单元；The backscattered light signal is transmitted back to the second port of the first dense wavelength division multiplexer, and the second end of the first dense wavelength division multiplexer receives the backscattered light signal Then, the backscattered light signal is divided into multiple signals of different wavelengths, and the backscattered light signal of the corresponding wavelength is removed from the corresponding channel of the first port of the first dense wavelength division multiplexer. Output to the laser generating gain unit, the laser generating gain unit;

具有更窄线宽的所述后向散射光信号在所述激光发生增益阵列中不断地被增益放大，最后所述激光发生增益单输出更窄的激光线宽，再将增益放大后的对应波长的所述后向散射光信号传输至所述第一密集型波分复用器；The backscattered light signal with the narrower linewidth is continuously amplified by the gain in the laser generating gain array, and finally the laser generating gain unit outputs a narrower laser linewidth, and then the corresponding wavelength after the gain is amplified The backscattered light signal is transmitted to the first dense wavelength division multiplexer;

所述第二密集型波分复用器在接收到所述光隔离器提供的所述光信号后，将所述光信号分成多束不同波长的所述光信号，并通过其各个第二端将对应波长的所述光信号输出。After the second dense wavelength division multiplexer receives the optical signal provided by the optical isolator, it divides the optical signal into multiple beams of the optical signals of different wavelengths, and passes through each of its second ends. The optical signal corresponding to the wavelength is output.
根据权利要求9所述的激光器，其特征在于，所述分布式散射回馈单元同时对多个波长的激光进行线宽同时压缩。9. The laser according to claim 9, wherein the distributed scattering feedback unit simultaneously compresses the line width of lasers of multiple wavelengths at the same time.
根据权利要求9所述的激光器，其特征在于，通过对所述分布式散射回馈单元内光波导的散射系数进行调节，以实现用更小的所述分布式散射回馈单元达成相同或更窄线宽的激光输出。The laser according to claim 9, wherein the scattering coefficient of the optical waveguide in the distributed scattering feedback unit is adjusted to achieve the same or narrower line with the smaller distributed scattering feedback unit. Wide laser output.
根据权利要求3所述的激光器，其特征在于，还包括第一光准直透镜、第二光准直透镜和可调谐滤波元件；The laser according to claim 3, further comprising a first optical collimating lens, a second optical collimating lens and a tunable filter element;

所述激光发生增益单元的第一输出端和第二输出端对应设置有第一薄膜和第二薄膜，所述第一薄膜和所述第二薄膜都具有透射和反射特性；The first output end and the second output end of the laser generating gain unit are correspondingly provided with a first film and a second film, and both the first film and the second film have transmission and reflection characteristics;

所述激光发生增益单元的所述第一输出端依次通过所述第一薄膜、所述第一光准直透镜连接所述分布式散射回馈单元的第一端；The first output end of the laser generating gain unit is connected to the first end of the distributed scattering feedback unit through the first film and the first light collimating lens in sequence;

所述激光发生增益单元的所述第二输出端依次通过所述第二薄膜、所述第二光准直透镜连接所述可调谐滤波元件；The second output end of the laser generating gain unit is connected to the tunable filter element through the second film and the second light collimating lens in sequence;

所述激光发生增益单元用于生成宽光谱的所述初始激光信号并分别传输给所述第一薄膜和所述第二薄膜，The laser generation gain unit is used to generate the broad-spectrum initial laser signal and transmit it to the first film and the second film, respectively,

所述第一薄膜在接收到所述初始激光信号后，将一部分激光信号传输给所述激光发生增益单元，另一部分光信号通过所述第一光准直透镜传输给所述分布式散射回馈单元；After receiving the initial laser signal, the first film transmits a part of the laser signal to the laser generating gain unit, and the other part of the optical signal is transmitted to the distributed scattering feedback unit through the first optical collimator lens ；

所述第二薄膜在接收到所述初始激光信号后，将一部分光信号传输给所述激光发生增益单元，另一部分光信号通过所述第二光准直透镜传输给所述可调谐滤波元件；After receiving the initial laser signal, the second film transmits a part of the optical signal to the laser generating gain unit, and the other part of the optical signal is transmitted to the tunable filter element through the second optical collimator lens;

所述可调谐滤波元件在接收到初始激光信号后，对所述初始激光信号进行波长选择和调谐，获得具有特定波长光信号，所述具有特定波长光信号一部分通过所述第二光准直透镜传输给所述第二薄膜，另一部分直接输出；After receiving the initial laser signal, the tunable filter element performs wavelength selection and tuning on the initial laser signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength passes through the second optical collimator lens Is transmitted to the second film, and the other part is directly output;

所述分布式散射回馈单元的第一端在接收到所述另一部分光信号后，对所述另一部分光信号进行线宽压缩，并通过所述第一光准直透镜将线宽压缩后后向散射光信号回馈传输给所述第一薄膜；After receiving the other part of the optical signal, the first end of the distributed scattering feedback unit performs line width compression on the other part of the optical signal, and compresses the line width through the first optical collimator lens. Feedback and transmit the scattered light signal to the first film;

所述激光发生增益单元在接收到回馈的所述后向散射光信号后，对所述后向散射光信号进行增益放大，并将增益放大后的所述后向散射光信号再次分别传输给所述第一薄膜和所述第二薄膜；After the laser generating gain unit receives the feedback backscattered light signal, it gains and amplifies the backscattered light signal, and transmits the backscattered light signal after the gain amplification to each of the backscattered light signals. The first film and the second film;

在达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述可调谐滤波元件的另一端输出。When the steady state is reached, after the optical signal with a specific wavelength undergoes cyclic linewidth compression by the distributed scattering feedback unit, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the other end of the tunable filter element.
根据权利要求12所述的激光器，其特征在于，所述分布式散射回馈单元还可以通过所述分布式散射回馈单元的第二端将线宽压缩后向前传输的光信号输出。The laser according to claim 12, wherein the distributed scattering feedback unit can also output the optical signal transmitted forward after the line width is compressed through the second end of the distributed scattering feedback unit.
根据权利要求3所述的激光器，其特征在于，包括第一光准直透镜、第二光准直透镜和可调谐滤波元件；4. The laser of claim 3, comprising a first optical collimating lens, a second optical collimating lens and a tunable filter element;

所述激光发生增益单元的第一输出端和第二输出端对应设置有第一薄膜和第二薄膜，所述第一薄膜具有透射和反射特性，所述第二薄膜具有反射特性，The first output end and the second output end of the laser generating gain unit are correspondingly provided with a first film and a second film, the first film has transmission and reflection characteristics, and the second film has reflection characteristics,

所述激光发生增益单元的第一输出端依次通过所述第一薄膜、所述第一光准直透镜连接所述分布式散射回馈单元的第一端；The first output end of the laser generating gain unit is connected to the first end of the distributed scattering feedback unit through the first film and the first light collimating lens in sequence;

所述激光发生增益单元的第二输出端连接所述第二薄膜，所述分布式散射回馈单元的第二端连接所述可调谐滤波元件；The second output end of the laser generating gain unit is connected to the second film, and the second end of the distributed scattering feedback unit is connected to the tunable filter element;

所述激光发生增益单元用于生成宽光谱的所述初始激光信号并分别传输给所述第一薄膜和所述第二薄膜，The laser generation gain unit is used to generate the broad-spectrum initial laser signal and transmit it to the first film and the second film, respectively,

所述第一薄膜在接收到所述初始激光信号后，将一部分光信号传输给所述激光发生增益单元，另一部分光信号通过所述第一光准直透镜和所述分布式散射回馈单元传输至可调谐滤波单元；After receiving the initial laser signal, the first film transmits a part of the optical signal to the laser generating gain unit, and the other part of the optical signal is transmitted through the first optical collimator lens and the distributed scattering feedback unit To tunable filter unit;

所述第二薄膜在接收到所述初始激光信号后，将所述初始激光信号传输给所述激光发生增益单元；After receiving the initial laser signal, the second film transmits the initial laser signal to the laser generating gain unit;

所述可调滤波单元接受到所述初始激光信号后，对所述初始激光信号进行波长的选择并调谐，以选择出具有特定波长光信号，所述具有特定波长光信号沿原光路返回至所述激光发生增益单元；所述激光发生增益单元接收所述具有特定波长光信号对所述具特定波长的光线号进行增益放大，并将增益放大后的所述具有特定波长光信号再次通过所述第一光准直透镜传输至所述分布式散射回馈单元；After receiving the initial laser signal, the tunable filter unit selects and tunes the wavelength of the initial laser signal to select an optical signal with a specific wavelength, and the optical signal with a specific wavelength returns to the original optical path along the original optical path. The laser generating gain unit; the laser generating gain unit receives the optical signal with a specific wavelength to gain amplify the light signal with the specific wavelength, and the amplified optical signal with the specific wavelength passes through the optical signal again The first light collimating lens is transmitted to the distributed scattering feedback unit;

所述分布式散射回馈单元的第一端在接收到所述具有特定波长光信号后，对所述具有特定波长光信号进行线宽压缩，并通过所述第一光准直透镜将线宽压缩后后向散射回馈光信号传输给所述激光发生增益单元进行增益放大；而将线宽压缩后前向传输光信号传输至所述可调谐滤波单元，并通过所述可调谐滤波单元的第二端输出；在达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述可调谐滤波元件输出。After receiving the optical signal with the specific wavelength, the first end of the distributed scattering feedback unit performs linewidth compression on the optical signal with the specific wavelength, and compresses the linewidth through the first optical collimator lens The backscattered feedback optical signal is transmitted to the laser generating gain unit for gain amplification; and the line width compressed forward transmission optical signal is transmitted to the tunable filter unit, and passes through the second tunable filter unit. When reaching a steady state, after the optical signal with a specific wavelength is cyclically compressed by the distributed scattering feedback unit, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the tunable filter element.
根据权利要求14所述的激光器，其特征在于，所述第二薄膜还具有透射特性，所述第二薄膜还与所述第二光准直透镜连接，所述第二薄膜在接收到光信号后，将所述光信号的一部分传输给所述激光发生增益单元，另一部分通过所述第二光准直透镜输出。14. The laser according to claim 14, wherein the second film further has a transmission characteristic, the second film is also connected to the second optical collimator lens, and the second film receives an optical signal. Then, a part of the optical signal is transmitted to the laser generating gain unit, and the other part is output through the second optical collimator lens.
根据权利要求14或15所述的激光器，其特征在于，还包括光隔离器，所述可调谐滤波元件与所述光隔离器连接，用于通过所述光隔离器将获得的单纵模超窄线宽光信号输出。The laser according to claim 14 or 15, further comprising an optical isolator, and the tunable filter element is connected to the optical isolator, and is used to obtain a single longitudinal mode super-mode optical isolator through the optical isolator. Narrow line width optical signal output.
根据权利要求14或15所述的激光器，其特征在于，所述分布式散射回馈单元包括具有高散射系数的特殊光纤、特殊气体材料制成的波导结构，或者是刻写在基板上的特殊散射波导。The laser according to claim 14 or 15, wherein the distributed scattering feedback unit comprises a special optical fiber with a high scattering coefficient, a waveguide structure made of a special gas material, or a special scattering waveguide written on a substrate .
根据权利要求14或15所述的激光器，其特征在于，通过所述分布式散射回馈单元来实现激光波长与有效分布式散射结构中腔长的自匹配；所述分布式散射回馈单元可以采用以瑞利散射为代表的所有分布式散射机制，通过对所述分布式散射回馈单元的散射系数和信号回馈比例进行调节，实现光信号线宽的循环压缩调节。The laser according to claim 14 or 15, wherein the distributed scattering feedback unit is used to realize the self-matching of the laser wavelength and the cavity length in the effective distributed scattering structure; the distributed scattering feedback unit can be Rayleigh scattering is a representative of all distributed scattering mechanisms. By adjusting the scattering coefficient and signal feedback ratio of the distributed scattering feedback unit, the cyclic compression adjustment of the optical signal line width is realized.
根据权利要求14或15所述的激光器，其特征在于，所述激光发生增益单元包括增益介质，所述增益介质在电激励作用下生成宽光谱的初始激光信号并分别传输给所述第一薄膜和所述第二薄膜，其在接收到光信号后，在激光谐振过程中，对该光信号进行增益放大，并将增益放大后的光信号再次分别传输给所述第一薄膜和第二薄膜。The laser according to claim 14 or 15, wherein the laser generating gain unit comprises a gain medium, and the gain medium generates a broad-spectrum initial laser signal under electrical excitation and transmits it to the first thin film. And the second film, after receiving the optical signal, in the laser resonance process, the optical signal is gain-amplified, and the gain-amplified optical signal is again transmitted to the first film and the second film .
根据权利要求12或14所述的激光器，其特征在于，所述激光发生增益单元、所述分布式散射回馈单元、所述第一光准直透镜、所述第二光准直透镜和所述可调谐滤波单元中至少所述激光发生增益单元、所述分布式散射回馈单元、所述第一光准直透镜和所述第二光准直透镜集成在基板上。The laser according to claim 12 or 14, wherein the laser generating gain unit, the distributed scattering feedback unit, the first light collimating lens, the second light collimating lens, and the In the tunable filter unit, at least the laser generating gain unit, the distributed scattering feedback unit, the first light collimating lens and the second light collimating lens are integrated on a substrate.
根据权利要求14或15所述的激光器，其特征在于，所述激光发生增益单元可覆盖激光增益的任意波段，其不具波长的选择性，适用于任意波段和任意类型激光线宽的深压缩。The laser according to claim 14 or 15, wherein the laser generating gain unit can cover any wavelength band of laser gain, it has no wavelength selectivity, and is suitable for deep compression of any wavelength band and any type of laser linewidth.
根据权利要求3所述的激光器，其特征在于，还包括第一光准直透镜和第二光准直透镜，The laser according to claim 3, further comprising a first light collimating lens and a second light collimating lens,

所述激光发生增益单元的第一输出端通过所述第一光准直透镜连接所述分布式散射回馈单元的第一端，所述激光发生增益单元的第二输出端连接所述第二光准直透镜的第一端；The first output end of the laser generation gain unit is connected to the first end of the distributed scattering feedback unit through the first light collimator lens, and the second output end of the laser generation gain unit is connected to the second light The first end of the collimating lens;

所述激光发生增益单元用于生成宽光谱的初始光信号，并对生成的光信号进行波长选择，获得具有特定波长光信号，所述具有特定波长光信号的一部分通过所述第一光准直透镜传输给所述分布式散射回馈单元的第一端，另一部分通过所述第二光准直透镜输出；The laser generating and gaining unit is used to generate a broad-spectrum initial optical signal, and perform wavelength selection on the generated optical signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength is collimated by the first light The lens is transmitted to the first end of the distributed scattering feedback unit, and the other part is output through the second light collimating lens;

所述分布式散射回馈单元的第一端在接收到所述具有特定波长光信号的所述一部分后，对该光信号进行线宽压缩，并通过所述第一光准直透镜将线宽压缩后的后向散射光信号传输给所述激光发生增益单元，所述激光发生增益单元在接收到回馈的所述后向散射光信号后，对回馈的所述后向散射光信号进行增益放大，针对增益放大后的光信号，将其一部分通过所述第二光准直透镜输出，另一部分通过所述第一光准直透镜再次传输给所述分布式散射回馈单元的第一端做进一步线宽压缩，After receiving the part of the optical signal with a specific wavelength, the first end of the distributed scattering feedback unit performs line width compression on the optical signal, and compresses the line width through the first optical collimator lens The latter backscattered light signal is transmitted to the laser generating gain unit, and the laser generating gain unit, after receiving the feedback backscattered light signal, performs gain amplification on the feedback backscattered light signal, For the optical signal after gain amplification, a part of it is output through the second optical collimator lens, and the other part is retransmitted to the first end of the distributed scattering feedback unit through the first optical collimator lens for further transmission. Wide compression,

当达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述第二光准直透镜输出。When the steady state is reached, after the optical signal with a specific wavelength undergoes cyclic linewidth compression by the distributed scattering feedback unit, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the second optical collimator lens.
根据权利要求22所述的激光器，其特征在于，所述分布式散射回馈单元包括具有高散射系数的特殊光纤、特殊气体材料波导，或刻写在基底上的特殊散射波导。The laser according to claim 22, wherein the distributed scattering feedback unit comprises a special optical fiber with a high scattering coefficient, a special gas material waveguide, or a special scattering waveguide written on a substrate.
根据权利要求22或23所述的激光器，其特征在于，通过对分布式散射回馈单元的散射系数和信号回馈比例进行调节，实现光信号线宽的深压缩和单纵模输出。The laser according to claim 22 or 23, characterized in that by adjusting the scattering coefficient and signal feedback ratio of the distributed scattering feedback unit, deep compression of the optical signal linewidth and single longitudinal mode output are realized.
根据权利要求22所述的激光器，其特征在于，所述激光发生增益单元包括增益介质和光纤光栅，所述增益介质在电激励作用下生成宽光谱的初始激光信号，生成的所述初始激光信号传输给所述光纤光栅，所述光纤光栅对生成的所述初始光信号进行波长选择，获得具有特定波长光信号，所述具有特定波长光信号的一部分通过所述第一光准直透镜传输给所述分布式散射回馈单元的第一端，另一部分通过所述第二光准直透镜输出；The laser according to claim 22, wherein the laser generating gain unit comprises a gain medium and a fiber grating, the gain medium generates a broad-spectrum initial laser signal under electrical excitation, and the generated initial laser signal Is transmitted to the fiber grating, and the fiber grating performs wavelength selection on the generated initial optical signal to obtain an optical signal with a specific wavelength, and a part of the optical signal with a specific wavelength is transmitted to the first optical collimator lens The other part of the first end of the distributed scattering feedback unit is output through the second light collimating lens;

所述分布式散射回馈单元的第一端在接收到具有特定波长光信号，对该光信号进行线宽压缩后，依次通过所述第一光准直透镜、所述光纤光栅将线宽压缩后的后向散射光信号传输给所述增益介质，所述增益介质在接收到回馈的所述后向散射光信号后，对回馈的所述后向散射光信号进行增益放大，针对增益放大后的所述后向散射光信号，将其一部分依次通过所述光纤光栅、所述第二光准直透镜输出，另一部分依次通过所述光纤光栅、所述第一光准直透镜再次传输给所述分布式散射回馈单元的第一端做进一步线宽压缩。After the first end of the distributed scattering feedback unit receives an optical signal with a specific wavelength, the optical signal is line-width compressed, and then the line-width is compressed through the first optical collimator lens and the fiber grating in sequence The backscattered light signal is transmitted to the gain medium. After receiving the backscattered light signal, the gain medium performs gain amplification on the backscattered light signal that is fed back. For the backscattered light signal, a part of it is sequentially output through the fiber grating and the second light collimating lens, and the other part is sequentially transmitted through the fiber grating and the first light collimating lens to the The first end of the distributed scattering feedback unit is further compressed.
根据权利要求22所述的激光器，其特征在于，还包括第一光隔离器，所述第二光准直透镜的第二端连接所述第一光隔离器。The laser according to claim 22, further comprising a first optical isolator, and a second end of the second optical collimator lens is connected to the first optical isolator.
根据权利要求26所述的激光器，其特征在于，还包括第二光隔离器，所述分布式散射回馈单元的第二端连接所述第二光隔离器，所述分布式散射回馈单元的第一端在接收到光信号，对该光信号进行线宽压缩后，通过所述第二光隔离器将线宽压缩后向前传输的光信号输出；当达到稳态时，所述具有特定波长光信号经过所述分布式散射回馈单元循环线宽压缩后，获得的单纵模超窄线宽光信号从所述第二光隔离器输出。The laser according to claim 26, further comprising a second optical isolator, the second end of the distributed scattering feedback unit is connected to the second optical isolator, and the second end of the distributed scattering feedback unit is connected to the second optical isolator. One end receives an optical signal and compresses the line width of the optical signal. The second optical isolator compresses the line width and then outputs the optical signal transmitted forward; when it reaches a steady state, the optical signal has a specific wavelength After the optical signal is cyclically compressed by the distributed scattering feedback unit, the obtained single longitudinal mode ultra-narrow linewidth optical signal is output from the second optical isolator.
根据权利要求22或23所述的激光器，其特征在于，所述分布式散射回馈单元可以采用包括瑞利散射在内的所有分布式散射机制，通过所述分布式散射回馈单元来实现激光波长与有效分布式反馈结构中腔长的自匹配。The laser according to claim 22 or 23, wherein the distributed scattering feedback unit can use all distributed scattering mechanisms including Rayleigh scattering, and the distributed scattering feedback unit is used to realize the laser wavelength and Self-matching of cavity length in an effective distributed feedback structure.
根据权利要求22或25所述的激光器，其特征在于，所述激光发生增益单元的增益介质可覆盖激光增益的任意波段，其不具波长的选择性，适用于任意波段和任意类型激光线宽的深压缩。The laser according to claim 22 or 25, wherein the gain medium of the laser generating gain unit can cover any wavelength band of the laser gain, it has no wavelength selectivity, and is suitable for any wavelength band and any type of laser line width. Deep compression.
根据权利要求27所述的激光器，其特征在于，所述激光发生增益单元、所述分布式散射回馈单元、所述第一光准直透镜、所述第二光准直透镜、所述第一光隔离器和所述第二光隔离器中至少所述激光发生增益单元、所述分布式散射回馈单元、所述第一光准直透镜和所述第二光准直透镜集成在基板上。The laser according to claim 27, wherein the laser generating gain unit, the distributed scattering feedback unit, the first optical collimating lens, the second optical collimating lens, the first In the optical isolator and the second optical isolator, at least the laser generating gain unit, the distributed scattering feedback unit, the first light collimating lens and the second light collimating lens are integrated on a substrate.