An optical frequency comb generation device, method, optical transmission device and optical communication system

Abstract

This application relates to the field of optical technology, and more particularly to an optical frequency comb generation device, method, optical emitting device, and optical communication system. The optical frequency comb generation device can be applied to scenarios such as optical communication and lidar. The device includes a laser, a beam splitter, a frequency shifter, and an optical microcavity. The laser generates a source scanning beam with a frequency varying in a first direction. The beam splitter decomposes the source scanning beam into a first scanning beam and a second scanning beam. The optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold of the optical microcavity. The frequency shifter changes the frequency of the second scanning beam to generate a third scanning beam with a frequency varying in a second direction. The optical microcavity generates a target beam with a spectrum matching the target optical frequency comb when the first scanning beam is in its red detuned region and the third scanning beam is in its blue detuned region. The optical frequency comb generation device provided in this application can generate optical frequency combs with narrow linewidths, exhibiting strong applicability and practicality.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to an optical frequency comb generation device, method, optical emission device, and optical communication system. Background Technology

[0002] With the rapid development of optical technology, optical frequency combs (OFCs) have been widely used in the optical field. Currently, the most common optical frequency combs are Kerr frequency combs (also known as microcavity frequency combs). A Kerr frequency comb is an optical frequency comb generated by laser light passing through the Kerr nonlinear characteristics of a nonlinear optical microcavity. Due to its high repetition rate, wide bandwidth, and extremely compact generation device (the radius of the optical microcavity it relies on is only on the order of hundreds of micrometers), Kerr frequency combs have significant applications in many fields such as lidar, optical communication, atomic clocks, and laser ranging. In practical optical communication scenarios (such as coherent optical communication), the linewidth of the Kerr frequency comb is one of the key parameters affecting communication quality. The smaller the linewidth of the Kerr frequency comb, the better the coherence and monochromaticity of the light source, and the lower the noise. Therefore, ensuring a narrow linewidth for the Kerr frequency comb has become a major research hotspot.

[0003] Existing technologies typically utilize laser frequency scanning to generate soliton mode-locked Kerr combs within optical microcavities, or employ a single-sideband modulator to achieve rapid frequency scanning of an ultra-narrow linewidth laser to generate soliton mode-locked Kerr combs within the optical microcavities. However, these methods all suffer from noise (primarily including random variations in the comb spacing caused by laser detuning jitter, comb frequency jitter caused by laser frequency jitter, and comb frequency jitter caused by thermal refractive noise of the optical microcavities), resulting in Kerr combs with relatively large linewidths. Therefore, eliminating the noise present during the comb generation process to obtain narrow-linewidth combs has become a pressing problem to be solved. Summary of the Invention

[0004] To address the aforementioned issues, this application provides an optical frequency comb generation device, method, optical emitting device, and optical communication system. This optical frequency comb generation device can reduce or even eliminate noise present during the generation of the optical frequency comb, thus enabling the generation of narrow linewidth optical frequency combs, which has strong applicability and practicality.

[0005] In a first aspect, embodiments of this application provide an optical frequency comb generation device. The device includes a laser, a beam splitter, a frequency shifter, and an optical microcavity. The laser generates a source scanning beam with a frequency varying in a first direction and emits the source scanning beam to the beam splitter. The beam splitter decomposes the source scanning beam into a first scanning beam and a second scanning beam, emits the first scanning beam to the optical microcavity, and emits the second scanning beam to the frequency shifter. Here, the optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold of the optical microcavity. The frequency shifter generates a third scanning beam with a frequency varying in a second direction based on the second scanning beam and emits the third scanning beam to the optical microcavity. The optical microcavity generates a target beam when the first scanning beam is in the red detuning region of the optical microcavity and the third scanning beam is in the blue detuning region of the optical microcavity. Here, the spectrum of the target beam is a target optical frequency comb.

[0006] In the above implementation, the optical microcavity is laser-scanned by the first and third scanning beams of the same origin. This reduces or eliminates three types of noise: random variation of the optical frequency comb spacing caused by the detuning of the first scanning beam, frequency jitter of the optical frequency comb caused by the frequency jitter of the laser, and frequency jitter of the optical frequency comb caused by the resonant frequency. This reduces or even eliminates the noise that easily produces linewidth enhancement effect in the optical frequency comb generation device, enabling it to generate a target optical frequency comb with a very narrow linewidth, thereby improving its applicability and practicality.

[0007] In conjunction with the first aspect, in a first alternative implementation, the first scanning beam and the third scanning beam have opposite transmission directions in the optical microcavity.

[0008] In the above implementation, the transmission directions of the first scanning beam and the third scanning beam are opposite, which can avoid the optical microcavity generating the target optical frequency comb based on the first scanning beam and the unnecessary optical frequency comb based on the third scanning beam at the same time. This eliminates the influence of the unnecessary optical frequency comb on the target optical frequency comb and ensures the stability and narrow linewidth performance of the target optical frequency comb.

[0009] In conjunction with the first aspect, or the first optional implementation of the first aspect, in the second optional implementation, the frequency change rate of the third scanning beam is equal to or greater than the frequency change rate of the first scanning beam.

[0010] In the above implementation, ensuring that the frequency change rate of the third scanning beam is equal to or greater than the frequency change rate of the first scanning beam can increase the probability of nonlinear effects occurring in the optical microcavity and increase the generation frequency of the target optical comb.

[0011] In conjunction with the first aspect, or the first to second alternative implementations of the first aspect, in a third alternative implementation, the device further includes a first waveguide and a circulator. A first end of the beam splitter is connected to the laser, a second end of the beam splitter is connected to a first end of the first waveguide, a second end of the first waveguide is connected to a first end of the circulator, and the optical microcavity is coupled between the first and second ends of the first waveguide. A third end of the beam splitter is connected to a first end of the frequency shifter, and a second end of the frequency shifter is connected to a second end of the circulator. The first waveguide is used to transmit the first scanning beam to the optical microcavity. The first waveguide and the circulator are used to transmit the third scanning beam to the optical microcavity. A third port of the circulator is used to output the target beam.

[0012] In the above implementation, the input of the first scanning beam and the third scanning beam to the optical microcavity and the output of the target beam from the optical microcavity are realized through the first waveguide and the circulator. The scheme is simple and easy to implement, which can reduce the structural complexity of the optical frequency comb generation device and improve the reliability of the optical frequency comb generation device.

[0013] In a fourth optional implementation, in conjunction with the third optional implementation of the first aspect, the device further includes a first amplifier and a second amplifier. The second end of the beam splitter is connected to the first end of the first waveguide via the first amplifier. The first amplifier is used to adjust the optical power of the first scanning beam and to transmit the first scanning beam with adjusted optical power to the first waveguide. The optical power of the first scanning beam with adjusted optical power is equal to or greater than the nonlinear effect power threshold. The third end of the beam splitter is connected to the first end of the frequency shifter via the second amplifier. The second amplifier is used to adjust the optical power of the second scanning beam and to transmit the second scanning beam with adjusted optical power to the frequency shifter.

[0014] In the above implementation, adding a first amplifier and a second amplifier to the optical frequency comb generating device facilitates the adjustment of the optical power of the first scanning beam and the second scanning beam, thereby improving the functional flexibility of the optical frequency comb generating device.

[0015] In conjunction with the fourth optional implementation of the first aspect, in the fifth optional implementation, the device further includes a first filter and a second filter. The first amplifier is connected to a first end of the first waveguide via the first filter. The first filter is used to filter noise from the first scanning beam and transmit the noise-filtered first scanning beam into the first waveguide. The second amplifier is connected to the frequency shifter via the second filter. The second filter is used to filter noise from the second scanning beam and transmit the noise-filtered second scanning beam into the frequency shifter.

[0016] In the above implementation, adding a first filter and a second filter to the optical frequency comb generation device can filter out the noise carried by the first scanning beam and the second scanning beam, thereby improving the generation efficiency of the target optical frequency comb and ensuring the stability of the target optical frequency comb.

[0017] In a sixth optional implementation, in conjunction with the fifth optional implementation of the first aspect, the device further includes a first polarization controller and a second polarization controller. The first filter is connected to a first end of the first waveguide via the first polarization controller. The first polarization controller is used to adjust the polarization state of the first scanning beam to the target polarization state corresponding to the optical microcavity, and to emit the polarization-adjusted first scanning beam into the first waveguide. The frequency shifter is connected to a second end of the circulator via the second polarization controller. The second polarization controller is used to adjust the polarization state of the third scanning beam to the target polarization state, and to emit the polarization-adjusted third scanning beam into the circulator.

[0018] In the above implementation, a first polarization controller and a second polarization controller are added to the optical frequency comb generation device. These two devices can adjust the polarization states of the first and third scanning beams entering the optical microcavity, thereby ensuring that the polarization states of the first and third scanning beams are consistent with the target polarization state of the optical microcavity. On the one hand, this can improve the light conversion efficiency of the optical microcavity, thereby improving the generation efficiency of the target optical frequency comb. On the other hand, it also allows other components in the device to use non-polarization-maintaining optics, reducing the cost of the optical frequency comb generation device.

[0019] In a seventh optional implementation, combining the third to sixth optional implementations of the first aspect, the device further includes a detector and a controller. The detector is connected to the third end of the circulator, and the controller is connected to the laser, the frequency shifter, and the detector. The detector is used to detect the light beam output from the third end of the circulator. When the light beam output from the third end of the circulator is the target light beam, the controller controls the laser to stop changing the frequency of the source scanning beam and controls the frequency shifter to stop changing the frequency of the third scanning beam.

[0020] In conjunction with the seventh optional implementation of the first aspect, in the eighth optional implementation, after the beam output from the third end of the circulator is the target beam, when the optical power of the beam output from the third end of the circulator changes, the controller is further configured to control the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the third end of the circulator recovers to the optical power of the target beam and then stops.

[0021] In the above implementation, if the optical power of the beam output from the third end of the circulator changes (i.e. it is no longer the optical power of the target beam), the frequency of the third scanning beam can be changed by controlling the frequency shifter through the controller, so that the optical power of the beam output from the third end of the circulator is restored to the optical power of the target beam. This ensures that the optical frequency comb generating device can continuously and stably output the target optical frequency comb.

[0022] In conjunction with the first aspect, or the first to second optional implementations of the first aspect, in the ninth optional implementation, the device further includes a second waveguide and a third waveguide. A first end of the beam splitter is connected to the laser, a second end of the beam splitter is connected to a first end of the second waveguide, and the optical microcavity is coupled between the first and second ends of the second waveguide. A third end of the beam splitter is connected to a first end of the frequency shifter, a second end of the frequency shifter is connected to a first end of the third waveguide, and the optical microcavity is coupled between the first and second ends of the third waveguide. The second waveguide is used to transmit the first scanning beam to the optical microcavity, the third waveguide is used to transmit the third scanning beam to the optical microcavity, and a second end of the second waveguide is used to output the target beam.

[0023] In the above implementation, the input of the first scanning beam and the third scanning beam to the optical microcavity and the output of the target beam from the optical microcavity are realized through the second waveguide and the third waveguide. The scheme is simple and low cost, which can reduce the structural complexity of the optical frequency comb generation device and also reduce the cost of the optical frequency comb generation device.

[0024] In conjunction with the ninth optional implementation of the first aspect, in the tenth optional implementation, the device further includes a first amplifier and a second amplifier. The second end of the beam splitter is connected to the first end of the second waveguide via the first amplifier. The first amplifier is used to adjust the optical power of the first scanning beam and to transmit the first scanning beam with adjusted optical power to the second waveguide. Here, the optical power of the first scanning beam with adjusted optical power is equal to or greater than the nonlinear effect power threshold. The third end of the beam splitter is connected to the first end of the frequency shifter via the second amplifier. The second amplifier is used to adjust the optical power of the second scanning beam and to transmit the second scanning beam with adjusted optical power to the frequency shifter.

[0025] In the above implementation, adding a first amplifier and a second amplifier to the optical frequency comb generating device facilitates the adjustment of the optical power of the first scanning beam and the second scanning beam, thereby improving the functional flexibility of the optical frequency comb generating device.

[0026] In conjunction with the tenth optional implementation of the first aspect, in the eleventh optional implementation, the device further includes a first filter and a second filter. The first amplifier is connected to the second waveguide via the first filter, and the first filter is used to filter noise from the first scanning beam and transmit the noise-filtered first scanning beam to the second waveguide. The second amplifier is connected to a first end of the frequency shifter via the second filter, and the second filter is used to filter noise from the second scanning beam and transmit the noise-filtered second scanning beam to the frequency shifter.

[0027] In the above implementation, adding a first filter and a second filter to the optical frequency comb generation device can filter out the noise introduced by the power adjustment of the first and second scanning beams, thereby improving the generation efficiency of the target optical frequency comb and ensuring its stability.

[0028] In conjunction with the eleventh optional implementation of the first aspect, in the twelfth optional implementation, the device further includes a first polarization controller and a second polarization controller. The first filter is connected to a first end of the second waveguide via the first polarization controller. The first polarization controller is used to adjust the polarization state of the first scanning beam to the target polarization state of the optical microcavity and to emit the polarization-adjusted first scanning beam into the second waveguide. The frequency shifter is connected to a first end of the third waveguide via the second polarization controller. The second polarization controller is used to adjust the polarization state of the third scanning beam to the target polarization state and to emit the polarization-adjusted third scanning beam into the third waveguide.

[0029] In the above implementation, a first polarization controller and a second polarization controller are added to the optical frequency comb generation device. These two devices can ensure that the polarization states of the first and third scanning beams are consistent with the target polarization state of the optical microcavity. On the one hand, this can improve the light conversion efficiency of the optical microcavity, thereby improving the generation efficiency of the target optical frequency comb. On the other hand, it also allows other components in the device to use non-polarization-maintaining optics, reducing the cost of the optical frequency comb generation device.

[0030] In a thirteenth optional implementation, combining the ninth to twelfth optional implementations of the first aspect, the device further includes a detector and a controller. The detector is connected to the second end of the second waveguide, and the controller is connected to the laser, the frequency shifter, and the detector. The detector is used to detect the beam output from the second end of the third waveguide. When the beam output from the second end of the third waveguide is the target beam, the controller controls the laser to stop changing the frequency of the source scanning beam and controls the frequency shifter to stop changing the frequency of the third scanning beam.

[0031] In conjunction with the thirteenth optional implementation of the first aspect, in the fourteenth optional implementation, after the beam output from the second end of the third waveguide is the target beam, when the optical power of the beam output from the second end of the second waveguide changes, the controller is further configured to control the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the second end of the second waveguide is equal to the optical power of the target beam and then stops.

[0032] In the above implementation, if the optical power of the beam output from the second end of the second waveguide changes, the frequency of the third scanning beam can be changed by controlling the frequency shifter through the controller, so that the optical power of the beam output from the second end of the second waveguide is restored to the optical power of the target beam. This ensures that the optical frequency comb generating device can continuously and stably output the target optical frequency comb.

[0033] In conjunction with the first aspect, or the first to fourteenth alternative implementations of the first aspect, in the fifteenth alternative implementation, the laser is a sub-Hertz linewidth laser.

[0034] Secondly, embodiments of this application provide a method for generating an optical frequency comb, applicable to the optical frequency comb generating device described in the first aspect above. The device includes a laser, a beam splitter, a frequency shifter, and an optical microcavity. The method includes: generating a source scanning beam with a frequency varying in a first direction using the laser, and emitting the source scanning beam to the beam splitter. The beam splitter decomposes the source scanning beam into a first scanning beam and a second scanning beam, emitting the first scanning beam to the optical microcavity and the second scanning beam to the frequency shifter. Here, the optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold of the optical microcavity. The frequency shifter generates a third scanning beam with a frequency varying in a second direction based on the second scanning beam, and sends the third scanning beam to the optical microcavity. The optical microcavity generates a target beam when the first scanning beam is in the red detuning region of the optical microcavity and the third scanning beam is in the blue detuning region of the optical microcavity, wherein the spectrum of the target beam is a target optical frequency comb.

[0035] In conjunction with the second aspect, in a first alternative implementation, the first scanning beam and the third scanning beam have opposite transmission directions in the optical microcavity.

[0036] In conjunction with the second aspect, or the first optional implementation of the second aspect, in the second optional implementation, the frequency change rate of the third scanning beam is equal to or greater than the frequency change rate of the first scanning beam.

[0037] In conjunction with the second aspect, or in one of the first to second alternative implementations of the second aspect, in a third alternative implementation, the device further includes a first waveguide and a circulator. A first scanning beam can be emitted from the optical microcavity via the first waveguide. The third scanning beam can also be transmitted to the optical microcavity via the first waveguide and the circulator.

[0038] In a fourth optional implementation, in conjunction with the third optional implementation of the second aspect, the device further includes a detector and a controller. The detector can detect the light beam output from the third end of the circulator. When it is determined that the light beam output from the third end of the circulator is the target light beam, the controller further controls the laser to stop changing the frequency of the source scanning beam and controls the frequency shifter to stop changing the frequency of the third scanning beam.

[0039] In conjunction with the fourth optional implementation of the second aspect, in the fifth optional implementation, after determining that the beam output from the third end of the circulator is the target beam, when it is determined that the optical power of the beam output from the third end of the circulator has changed, the frequency shifter can be controlled by the controller to change the frequency of the third scanning beam until the optical power of the beam output from the third end of the circulator recovers to the optical power that hits the target beam.

[0040] In conjunction with the second aspect, or the first to second alternative implementations of the second aspect, in a sixth alternative implementation, the device further includes a second waveguide and a third waveguide. The first scanning beam can be emitted from the optical microcavity via the second waveguide. The third scanning beam can also be emitted from the optical microcavity via the third waveguide.

[0041] In a seventh optional implementation, in conjunction with the sixth optional implementation of the second aspect, the device further includes a detector and a controller. The detector is connected to the second end of the second waveguide, and the controller is connected to the laser, the frequency shifter, and the detector. The detector can detect the light beam output from the second end of the second waveguide. When it is determined that the light beam output from the second end of the second waveguide is the target light beam, the controller further controls the laser to stop changing the frequency of the source scanning beam and controls the frequency shifter to stop changing the frequency of the third scanning beam.

[0042] In conjunction with the seventh optional implementation of the second aspect, in the eighth optional implementation, after determining that the beam output from the second end of the second waveguide is the target beam, when it is determined that the optical power of the beam output from the second end of the second waveguide has changed, the controller further controls the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the second end of the second waveguide recovers to the optical power of the target beam and then stops.

[0043] In a ninth optional implementation, combining the third to eighth optional implementations of the second aspect, the device further includes a first amplifier and a second amplifier. The optical power of the first scanning beam can be adjusted via the first amplifier. The adjusted optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold. The optical power of the second scanning beam can be adjusted via the second amplifier.

[0044] In conjunction with the ninth optional implementation of the second aspect, in the tenth optional implementation, the device further includes a first filter and a second filter. The first filter can be used to filter out noise from the first scanning beam after optical power adjustment. The second filter can be used to filter out noise from the second scanning beam after optical power adjustment.

[0045] In conjunction with the tenth optional implementation of the second aspect, in the eleventh optional implementation, the device further includes a first polarization controller and a second polarization controller. The first polarization controller can adjust the polarization state of the noise-filtered first scanning beam to the target polarization state of the optical microcavity. The second polarization controller can also adjust the polarization state of the third scanning beam to the target polarization state.

[0046] In conjunction with the second aspect, or, in the first to the second aspect, which are optional implementations, in the twelfth optional implementation, the laser is a sub-Hertz linewidth laser.

[0047] Thirdly, embodiments of this application provide an optical emitting device. The optical emitting device includes an optical frequency comb generating device and an optical signal processor as described in any one of the first aspects above. The optical frequency comb generating device and the optical signal processor are interconnected. The optical frequency comb generating device is used to generate a target light beam. Here, the spectrum of the target light beam is a target optical frequency comb. The optical signal processor is used to modulate the target light beam and output target signal light.

[0048] In conjunction with the third aspect, in one optional implementation, the optical frequency comb generating device can specifically be an optical transmitter or optical receiver in a coherent optical communication system, or an integrated light source in a lidar system.

[0049] Fourthly, embodiments of this application provide an optical communication system. The optical communication system includes an optical transmitting device and an optical receiving device as described in any one of the first aspects above. The optical transmitting device and the optical receiving device are connected together. The optical transmitting device is used to generate and transmit target signal light based on a target beam to the optical receiving device.

[0050] The solutions provided in the second to fourth aspects above are used to realize or cooperate with the optical frequency comb generating device provided in any of the first aspects above, and therefore can achieve the same or corresponding beneficial effects as the first aspect, which will not be elaborated here.

[0051] In summary, the optical frequency comb generation equipment and method provided in the embodiments of this application can effectively reduce or even eliminate the noise present in the optical frequency comb generation process, and can obtain a narrow linewidth optical frequency comb. Attached Figure Description

[0052] Figure 1 This is a schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0053] Figure 2 This is a schematic diagram illustrating red detuning and blue detuning provided in an embodiment of this application;

[0054] Figure 3 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0055] Figure 4 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0056] Figure 5 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0057] Figure 6 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0058] Figure 7 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0059] Figure 8 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0060] Figure 9 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0061] Figure 10 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0062] Figure 11 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0063] Figure 12 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0064] Figure 13 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0065] Figure 14 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application;

[0066] Figure 15 This is a schematic flowchart of the optical frequency comb generation method provided in the embodiments of this application;

[0067] Figure 16 This is a schematic diagram of the structure of an optical emitting device provided in an embodiment of this application;

[0068] Figure 17 This is a schematic diagram of the structure of an optical communication system provided in an embodiment of this application. Detailed Implementation

[0069] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0070] Existing technologies typically utilize laser frequency scanning to generate soliton mode-locked Kerr combs within optical microcavities, or employ a single-sideband modulator to achieve rapid frequency scanning of an ultra-narrow linewidth laser to generate soliton mode-locked Kerr combs within the optical microcavities. However, these methods cannot overcome noise issues, including random variations in the optical frequency comb spacing caused by laser detuning jitter, optical frequency comb jitter caused by laser amplitude jitter, and optical frequency jitter caused by thermal refractive noise of the optical microcavities. Consequently, they cannot achieve narrow linewidth optical frequency combs.

[0071] Therefore, the technical problem to be solved by this application is: how to eliminate the noise present in the generation process of the optical frequency comb in order to obtain a narrow linewidth optical frequency comb.

[0072] Example 1

[0073] To address the aforementioned problems, this application provides an optical frequency comb generation device. In this device, two beams of light originating from the same source simultaneously enter an optical microcavity and perform frequency scanning. When one beam is located in the red detuning region of the microcavity and the other in the blue detuning region, a target beam with the spectrum of the target optical frequency comb can be generated. During this process, the introduction of two beams of light from the same source cancels out the noise present in the optical frequency comb generation process, thereby reducing or eliminating the noise. Therefore, this optical frequency comb generation device can generate narrow-linewidth optical frequency combs.

[0074] The following will combine Figures 1 to 14 This application provides a detailed description of the structure and working principle of the optical frequency comb generation device.

[0075] Please see Figure 1 , Figure 1 This is a schematic diagram of the optical frequency comb generation device provided in an embodiment of this application. Figure 1 As shown, the optical frequency comb generating device 100 may include a laser 10, a beam splitter 20, a frequency shifter 30, and an optical microcavity 40. The laser 10 is connected to the beam splitter 20, the beam splitter 20 is also connected to the frequency shifter 30 and the optical microcavity 40, and the frequency shifter 30 is also connected to the optical microcavity 40.

[0076] In actual operation, laser 10 can be used to generate a beam with a frequency varying in a first direction (hereinafter referred to as the source scanning beam for ease of distinction), and emit this source scanning beam to beam splitter 20. Alternatively, laser 10 can be understood as performing frequency scanning using the first scanning beam. It should be understood that the frequency varying in the first direction means that the frequency of the source scanning beam gradually changes from small to large (i.e., from small to large in the first direction) or gradually changes from large to small (i.e., from large to small in the first direction). Furthermore, the variation of the source scanning beam in the first direction can be an equal or unequal variation; this application does not specifically limit this. Beam splitter 20 can be used to split the source scanning beam to obtain two beams (hereinafter referred to as the first scanning beam and the second scanning beam for ease of distinction), emit the first scanning beam to optical microcavity 40, and emit the second scanning beam to frequency shifter 30. The optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold of optical microcavity 40. It should be understood that the beam splitter 20 can use any splitting ratio to obtain the first scanning beam and the second scanning beam mentioned above. This application does not specifically limit the splitting ratio of the beam splitter 20. It should also be noted that the nonlinear effect power threshold of any microcavity is one of the necessary conditions to be met to excite the nonlinear effect of the microcavity. The power of the light entering the microcavity can only excite the nonlinear effect of the microcavity if it is equal to or greater than this nonlinear effect power threshold. In practical applications, microcavities with different structures may have different nonlinear effect power thresholds. Therefore, the value of the nonlinear effect threshold of the optical microcavity 40 can be determined by the structure of the optical microcavity 40. This application does not specifically limit this. The frequency shifter 30 can be used to change the frequency of the second scanning beam to generate a scanning beam with a frequency that changes in the second direction (for ease of distinction, it will be described as the third scanning beam below), and emit the third scanning beam to the optical microcavity 40. Similarly, it can also be understood that the frequency shifter 30 is performing frequency scanning through the third scanning beam. Here, the second direction can be opposite to or the same as the first direction described above, depending on the actual design requirements, and this application does not limit this. Furthermore, the frequencies of the first and third scanning beams are different when entering the optical microcavity 40. Optionally, the frequency change rate of the third scanning beam must be equal to or greater than the frequency change rate of the first (or second) scanning beam. In other words, the frequency scanning speed of the frequency shifter 30 must be equal to or greater than the frequency scanning speed of the laser 10. For example, in practical implementation, the laser 10 can perform a normal-speed frequency scan, while the frequency shifter 30 performs a fast-speed frequency scan.Here, ensuring that the frequency change rate of the third scanning beam is equal to or greater than the frequency change rate of the first scanning beam can increase the probability of the optical microcavity 40 undergoing nonlinear effects (i.e., entering a single dissipative soliton state), thereby increasing the generation speed of the target optical frequency comb.

[0077] To facilitate understanding of the functions of laser 10, beam splitter 20, and frequency shifter 30, the working principles of these components will be illustrated below with examples. Assume the first direction is from small to large, and the second direction is from large to small. At time t0, laser 10 generates and outputs a source scanning beam L00 with frequency f0. Beam splitter 20 decomposes the source scanning beam L00 into a first scanning beam L10 and a second scanning beam L20 with frequencies f0, and transmits the first scanning beam L10 to optical microcavity 20 and the second scanning beam L20 to frequency shifter 30. After receiving the second scanning beam L20, frequency shifter 30 can shift the frequency of the second scanning beam L20 based on the received second control signal S20 to obtain a third scanning beam L30 with frequency f30. Then, at time t1 after time t0, laser 10 generates a source scanning beam L01 with frequency f1 and emits it to beam splitter 20. Here, frequency f1 is greater than frequency f0. Beam splitter 20 decomposes the source scanning beam L01 into a first scanning beam L11 and a second scanning beam L21 with frequency f1, and emits the first scanning beam L11 to optical microcavity 40 and the second scanning beam L21 to frequency shifter 30. After receiving the second scanning beam L21, frequency shifter 30 shifts the second scanning beam to obtain a third scanning beam L31 with frequency f31, where frequency f30 is less than frequency f31. Further, at time t2 after time t1, laser 10 generates a source scanning beam L02 with frequency f2 and emits it to beam splitter 20. Here, frequency f2 is greater than frequency f1. The beam splitter 20 decomposes the source scanning beam L02 into a first scanning beam L12 and a second scanning beam L22 with a frequency of f2. The first scanning beam L12 is emitted to the optical microcavity 40, and the second scanning beam L22 is emitted to the frequency shifter 30. After receiving the second scanning beam L22, the frequency shifter 30 shifts the frequency of the second scanning beam to obtain a third scanning beam L32 with a frequency of f32, where the frequency f32 is less than the frequency f31. Similarly, under the action of the laser 10 and the frequency shifter 30, the frequency of the first scanning beam gradually increases, and the frequency of the third scanning beam gradually decreases.

[0078] Furthermore, the optical microcavity 40 can continuously receive the aforementioned first and third scanning beams. Over time, the input of the third scanning beam causes energy to accumulate within the optical microcavity 40, forming a heat source. This heat source causes the resonant spectral lines of the optical microcavity 40 to shift towards longer wavelengths (i.e., causing a change in the resonant wavelength of the optical microcavity 40). Simultaneously with the change in the resonant wavelength of the optical microcavity 40, the frequencies of the first and third scanning beams also continuously change, ultimately causing the first scanning beam to enter the red detuning region of the optical microcavity 40 and the third scanning beam to enter the blue detuning region. It should be noted that red detuning of the microcavity refers to the incident beam wavelength being larger than the resonant wavelength of the microcavity, while blue detuning refers to the incident beam wavelength being smaller than the resonant wavelength of the microcavity. For example, consider the aforementioned first and third scanning beams. Please refer to [link to relevant documentation]. Figure 2 , Figure 2 This is a schematic diagram illustrating red detuning and blue detuning provided in an embodiment of this application. Figure 2 The diagram illustrates the positional relationship between the wavelengths of the first and third scanning beams and the resonant spectrum of the optical microcavity 40 at a specific moment (here assumed to be T) during the generation of the target optical frequency comb. Figure 2 As shown, at time T, the wavelength λ0 corresponding to the trough of the resonance spectrum of the optical microcavity 40 is the resonant wavelength of the optical microcavity 40. At this time, the wavelength of the first scanning beam is λ1, which is greater than the resonant wavelength λ0 of the optical microcavity 40. Therefore, the first scanning beam is in the red-detuned resonant mode of the optical microcavity 40. Meanwhile, the wavelength of the third scanning beam is λ2, which is less than the resonant wavelength λ0 of the optical microcavity 40. Therefore, the third scanning beam is in the blue-detuned resonant mode of the optical microcavity 40. When the first scanning beam is in the red-detuned region and the third scanning beam is in the blue-detuned region of the optical microcavity 40, the nonlinear effect of the optical microcavity 40 can be excited, thereby generating a corresponding dissipative soliton mode-locked Kerr optical frequency comb. In short, when the first scanning beam is in the red detuning region of the optical microcavity 40 and the third scanning beam is in the blue detuning region of the optical microcavity 40, the optical microcavity 40 can generate and output a beam with the spectrum of the target optical frequency comb (i.e., a narrow linewidth optical frequency comb) (for ease of distinction, the target beam will be used as a substitute for description below).

[0079] Optionally, the first and third scanning beams propagate in opposite directions within the optical microcavity 40. For example, when the first scanning beam propagates clockwise within the optical microcavity 40, the third scanning beam propagates counterclockwise. Conversely, when the first scanning beam propagates counterclockwise within the optical microcavity 40, the third scanning beam propagates clockwise. By having the first and third scanning beams propagate in opposite directions, the optical microcavity 40 avoids generating unnecessary optical frequency combs simultaneously with the first scanning beam and the third scanning beam. This eliminates the influence of unnecessary optical frequency combs on the target optical frequency comb, ensuring the stability and narrow linewidth performance of the target optical frequency comb.

[0080] The following section will explain in detail the principle by which the optical frequency comb generating device 100 can reduce or even eliminate this noise, combining the noise generation mechanism in the optical frequency comb generation process and the nonlinear effect principle of the optical microcavity 40. Here, it is assumed that the specific detuning amount of the third scanning beam is δ. A The specific detuning of the first scanning beam is δ P The frequency shift amount of frequency shifter 30 is f AOM The resonant frequency of the optical microcavity 40 is v. C Here, the frequency shift amount of frequency shifter 30 is the magnitude of the frequency that the frequency shifter can change each time, the frequency shift amount f. AOM It is usually a fixed value. In actual implementation, the detuning amount δ A Typically affected by the frequency jitter of the third scanning beam itself. A Thermal jitter of the microcavity resonant mode of optical microcavity 40 T Self-phase modulation of the third scanning beam v (SPM，A) and the first scanning beam cross-phase modulation v (XPM，P) The influence of detuning δ P Typically affected by the frequency fluctuation of the first scanning beam itself. P Thermal jitter of the microcavity resonant mode of optical microcavity 40 T Self-phase modulation v of the first scanning beam (SPM，P) and the third scanning beam cross-phase modulation v (XPM，A) The influence of frequency scanning. Here, because the frequencies of the first and third scanning beams are constantly changing during the frequency scanning process, the frequency jitter of the scanning beam itself is the frequency of the scanning beam at a certain moment. For example, assuming the frequency of the first scanning beam at time t4 is f4, then the frequency jitter of the first scanning beam at time t4 is f4. The so-called microcavity resonant mode thermal jitter v... T This refers to the change in the resonant frequency of the optical microcavity 40 due to temperature variations. The so-called self-phase modulation v of the first scanning beam...(SPM，P) Essentially, this refers to the frequency change of the first scanning beam due to its self-phase modulation. Similarly, the self-phase modulation v of the third scanning beam... (SPM，A) This refers to the frequency change of the third scanning beam due to phase modulation. The so-called third scanning beam cross-phase modulation (v) (XPM，A) Essentially, this refers to the frequency change of the first scanning beam caused by its cross-phase modulation with the third scanning beam. Similarly, the cross-phase modulation v of the first scanning beam... (XPM，P) This refers to the frequency change of the third scanning beam caused by its cross-phase modulation with the first scanning beam. Combining the above information, the detuning amount δ4 satisfies the following formula (1):

[0081] δ A =(v A -v c )-v T -v (SPM，A) -v (XPM，P) (1)

[0082] And the detuning amount δ P It can satisfy the following formula (2):

[0083] δ P =(v P -v c )-v T -v (SPM，P) -v (xPM，A) (2)

[0084] In the above implementation, since the first scanning beam and the third scanning beam are from the same source beam, the specific detuning amount δ4 of the first scanning beam and the specific detuning amount δ of the third scanning beam are different. P The following formula (3) should be satisfied:

[0085] δ P =δ A -f AOM +v NL (3)

[0086] Among them, v NL The difference in detuning between the first and third scanning beams due to nonlinear phase shift is related to the actual power of the first and third scanning beams in the optical microcavity 40, and can satisfy the following formula (4):

[0087] v NL =(v (SPM，A) -v (SPM，P) )+(v (XPM，A) -v (XPM，P) (4)

[0088] Combining the above formula (3), it can be seen that in the actual working process, the detuning of the first scanning beam jitters (here assumed to be Δδ). P This is mainly due to the detuning jitter of the third scanning beam (here assumed to be Δδ). A The difference in detuning between the first and third scanning beams due to nonlinear phase shift, v NL The jitter (here assumed to be Δv) NL Therefore, the detuning of the first scanning beam is determined by Δδ. P The following formula (5) should be satisfied:

[0089] Δδ P =Δδ A -f AOM +Δv NL (5)

[0090] According to the nonlinear phase shift theory of optical microcavities, when Δδ A When the power is reduced, the optical power of the third scanning beam in the optical microcavity 40 will increase, and the optical power of the first scanning beam will decrease. Combined with formula (4), it can be seen that this will lead to Δv NL Increase. And when Δδ A When the beam size increases, the optical power of the third scanning beam in the optical microcavity 40 decreases, while the optical power of the first scanning beam increases. This will cause Δv to increase. NL It decreases. Therefore, we can conclude that Δδ A With Δv NL The value changes in the opposite direction, that is, if Δδ A If it increases, then Δv NL Decrease if Δδ A If it decreases, then Δv NL Increase. Based on this conclusion and the content of formula (5), it can be seen that in the optical frequency comb generating device 100 mentioned above, due to the detuning jitter Δδ of the first scanning beam... P The decisive factor Δδ A With Δv NL They cancel each other out, while the frequency shift f AOM Typically, this is a fixed value, so by properly setting the optical power and initial frequency of the first and third scanning beams, Δδ can be made... P The value is very small or zero, so the optical frequency comb generating device 100 provided in this application can reduce or even eliminate the jitter of the detuning amount of the first scanning beam, thereby reducing or eliminating the noise of random changes in the optical frequency comb interval caused by the jitter of the detuning amount of the first scanning beam, thereby ensuring the narrow linewidth performance of the target optical frequency comb.

[0091] Furthermore, as described above, in actual operation, the laser 10 only needs to perform a normal frequency scan, not a rapid scan. Therefore, the frequency jitter noise of the optical frequency comb caused by the frequency jitter of the laser 10 in the optical frequency comb generation device 100 is very small or non-existent. In addition, according to formulas (1) and (2) above, the thermal-refractive noise (TRN) of the optical microcavity 40 mainly causes the resonant frequency of the optical microcavity 40 to be v. C The jitter, however, in the optical frequency comb generating device 100 described above, the first scanning beam and the third scanning beam are from the same source, and the blue-detuned third scanning beam and the red-detuned first scanning beam together keep the optical microcavity 40 in a self-heating locked state, so the resonant frequency caused by thermal refractive noise is v. C The jitter and thermal jitter of the microcavity resonant mode of the optical microcavity 40 T They cancel each other out (i.e., the microcavity mode laser cooling effect), so the resonant frequency mentioned above is v C The frequency jitter caused by the vibration of the optical frequency comb is very small or non-existent.

[0092] Therefore, based on the above, it can be concluded that in the optical frequency comb generating device 100, thanks to the introduction of the third scanning beam, which originates from the same source as the first scanning beam, the random variation of the optical frequency comb interval caused by the detuning of the first scanning beam, the frequency jitter of the optical frequency comb caused by the frequency jitter of the laser 10, and the frequency jitter of the optical frequency comb due to the resonant frequency v C The three types of noise—frequency jitter of the optical frequency comb caused by jitter—can be reduced or eliminated. Therefore, the noise that easily produces linewidth enhancement effect in the optical frequency comb generating device 100 provided in this application will be reduced or even eliminated. It can generate a target optical frequency comb with a very narrow linewidth, and therefore it is highly practical.

[0093] It should be further noted that, in actual implementation, the laser 10 is a tunable laser. The beam splitter 20 can be any form of passive optical device with beam-splitting capabilities; this application does not impose specific limitations on the form of the beam splitter 20. The frequency shifter 30 can be any form of optical device with high-precision frequency-shifting characteristics, such as an acousto-optic frequency shifter. The optical microcavity 40 can specifically be a Kerr nonlinear device, a microring, a microdisk, etc.

[0094] For some feasible implementation methods, please refer to Figure 3 , Figure 3 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. It should be understood that... Figure 3 The optical microcavity 40 is shown in the form of a microring. For example... Figure 3As shown, the optical frequency comb generating device 100 may further include a first waveguide 50 and a circulator 60. In actual implementation, the first end of the beam splitter 20 is connected to the laser 10 (or, in other words, connected to the output end of the laser 10), the second end of the beam splitter 20 is connected to the first end of the first waveguide 50, and the second end of the first waveguide 50 is connected to the first end of the circulator 60. Preferably, the first waveguide 50 is a straight waveguide. The optical microcavity 40 is coupled between the first and second ends of the first waveguide 50, or in other words, the optical microcavity 40 is positioned close to the first waveguide 50, close but not in contact, with a certain distance between them. The third end of the beam splitter 20 is connected to the first end of the frequency shifter 30, and the second end of the frequency shifter 30 is connected to the second end of the circulator 60. The third end of the circulator 60 can serve as the output end of the optical frequency comb generating device 100, used to output the beam output by the optical microcavity 40.

[0095] In actual operation, the first waveguide 50 is used to transmit the first scanning beam to the optical microcavity 40, and the first waveguide 50 and circulator 60 are used to transmit the third scanning beam to the optical microcavity 40. When the optical microcavity 40 outputs a target beam, the third port of the circulator 60 is used to output the target beam. Specifically, the beam splitter 20 can emit the first scanning beam to the first waveguide 50 through its second end. The first waveguide 50 can receive the first scanning beam through its first end. During the transmission of the first scanning beam from the first end to the second end of the first waveguide 50, when it passes a position close to the optical microcavity 40, the first scanning beam can couple to the optical microcavity 40 and be conducted therein. Figure 3 As shown, after the first scanning beam enters the optical microcavity 40 through the first waveguide 50, it can be propagated counterclockwise within the optical microcavity 40. Simultaneously, the frequency shifter 30 can emit the aforementioned third scanning beam to the circulator 60 through its second port. The circulator 60 can receive the third scanning beam through its second port and emit the third scanning beam back to the first waveguide 50 through its first port. The first waveguide 50 can receive the third scanning beam through its second end. During the transmission of the third scanning beam from the second end to the first end of the first waveguide 50, when it passes a position near the optical microcavity 40, the third scanning beam can couple into the optical microcavity 40 and be propagated therein. Figure 3As shown, after the third scanning beam enters the optical microcavity 40 through the first waveguide 50, it can be propagated in a clockwise direction within the optical microcavity 40. Furthermore, when the first scanning beam is in the red detuning region of the optical microcavity 40 and the third scanning beam is in the blue detuning region of the optical microcavity 40, the optical microcavity 40 can generate and output a target beam with the spectrum of the target optical frequency comb. This target beam will be coupled from the optical microcavity 40 to the first waveguide 50, and then transmitted through the first waveguide 50 to the circulator 60, and finally output from the third port of the circulator 60.

[0096] It should be noted that the preceding description of the functions of the first waveguide 50 and the circulator 60 used a scenario where the first scanning beam enters from the first end of the first waveguide 50 and the third scanning beam enters from the second end of the first waveguide 50 as an example. In this case, the first scanning beam is guided counterclockwise in the optical microcavity 40, and the third scanning beam is guided clockwise in the optical microcavity 40. In another alternative scenario, the first scanning beam can also enter from the second end of the first waveguide 50, and the third scanning beam can also enter from the first end of the first waveguide 50. In this case, the first scanning beam will be guided clockwise in the optical microcavity 40, and the third scanning beam will be guided counterclockwise.

[0097] In the above implementation, the input of the first scanning beam and the third scanning beam to the optical microcavity 40 and the output of the target beam from the optical microcavity 40 are realized through the first waveguide 50 and the circulator 60. The scheme is simple and easy to implement, which can reduce the structural complexity of the optical frequency comb generating device 100 and improve the reliability of the optical frequency comb generating device 100.

[0098] Furthermore, in Figure 3 Based on the structure shown, please refer to Figure 4 , Figure 4 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 4 As shown, the optical frequency comb generating device 100 should also include a detector 70 and a controller 80. The detector 70 is connected to the third end of the circulator 60, and the controller 80 is connected to the laser 10, the frequency shifter 30, and the detector 70.

[0099] In actual operation, the controller 80 generates and sends a first control signal to the laser 10, which controls the frequency of the output beam of the laser 10. The laser 10 then generates and outputs the aforementioned source scanning beam based on this first control signal. The controller 80 also generates and sends a second control signal to the frequency shifter 30, which includes the frequency shift amount corresponding to the frequency shifter 30. The frequency shifter 30 then increases the frequency shift amount based on the original frequency of the second scanning beam, thereby obtaining and outputting the third scanning beam. The detector 70 is used to detect the beam output from the third end of the circulator 60. Specifically, the detector 70 can detect the spectrum of the beam output from the third end of the circulator 60 and send the detected spectrum to the controller 80. After receiving the spectrum from the detector 70, the controller 80 can analyze the spectrum to determine whether it is the target optical frequency comb. When the first scanning beam is in the red detuning region of the optical microcavity 40 and the third scanning beam is in the blue detuning region of the optical microcavity 40, the third end of the circulator 60 can output the aforementioned target beam. The detector 70 can detect the spectrum of the target beam and send it to the controller 80. After receiving the spectrum of the target beam, the controller 80 can determine that the beam output from the third end of the circulator 60 is the target beam, and thus determine that the optical microcavity 40 has generated the target optical frequency comb. Then, the controller 80 can send a third control signal to the laser 10 to control the laser 10 to stop the frequency change of the source scanning beam (i.e., control the laser 10 to keep the frequency of the currently output beam unchanged and stop its frequency scanning). At the same time, the controller 80 can also output a fourth control signal to the frequency shifter 30 to control the frequency shifter 30 to stop the frequency change of the second scanning beam (i.e., control the frequency shifter to keep the frequency of its output beam equal to the frequency of its input beam and stop its frequency scanning). If the first scanning beam is not in the red detuning region of the optical microcavity 40, and / or the third scanning beam is not in the blue detuning region of the optical microcavity 40, after the detector 70 sends the spectrum of the beam output from the third end of the circulator 60 to the controller 80, the controller 80 can analyze the spectrum and determine that the beam output from the third end of the circulator 60 is not the target beam, thus confirming that the optical microcavity 40 has not yet generated the target optical frequency comb. Then, the controller 80 can continue to control the laser 10 to generate the aforementioned source scanning beam and continue to control the frequency shifter 30 to generate the aforementioned third scanning beam. In short, the detector 70 is used to detect the beam output from the third end of the circulator 60. The controller 80 is used to continue controlling the laser 10 and the frequency shifter 30 to perform frequency scanning when the detector 70 determines that the beam output from the third end of the circulator 60 is not the target beam.The controller 80 is also used to control the laser 10 to stop the change in the frequency of the source scanning beam and control the frequency shifter 30 to stop the change in the frequency of the third scanning beam when the detector 70 determines that the beam output from the third end of the circulator 60 is the target beam.

[0100] For some feasible implementation methods, please refer to Figure 5 , Figure 5 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 5 As shown, the optical frequency comb generating device 100 may further include a first amplifier 91 and a second amplifier 92. The second end of the beam splitter 20 is connected to the first end of the first waveguide 50 via the first amplifier 91. Alternatively, one end of the first amplifier 91 is connected to the second end of the beam splitter 20, and the other end is connected to the first end of the first waveguide 50. The third end of the beam splitter 20 is connected to the first end of the frequency shifter 30 via the second amplifier 92. Alternatively, one end of the second amplifier 92 is connected to the third end of the beam splitter 20, and the other end is connected to the first end of the frequency shifter 30.

[0101] In actual operation, the first amplifier 91 is used to adjust the optical power of the first scanning beam and emit the first scanning beam with adjusted optical power to the first waveguide 50. Here, the optical power of the first scanning beam with adjusted optical power must be equal to or greater than the nonlinear effect power threshold of the optical microcavity 40. The second amplifier 92 is used to adjust the optical power of the second scanning beam and emit the second scanning beam with adjusted optical power to the frequency shifter 30. For example, the first amplifier 91 can be used to adjust the optical power of the first scanning beam to a first preset optical power and emit the first scanning beam with the first preset optical power to the first waveguide 50. Here, the first preset optical power is equal to or greater than the nonlinear effect power threshold corresponding to the optical microcavity 40. The second amplifier 92 can be used to adjust the optical power of the second scanning beam to a second preset optical power and emit the second scanning beam with the second preset optical power to the frequency shifter 30, so that the optical power of the third scanning beam that subsequently enters the optical microcavity 40 is the second preset optical power. Here, the aforementioned first preset optical power and second preset optical power can be empirical values ​​obtained by performing multiple target optical frequency comb generation experiments on the optical frequency comb generation device 100 provided in this application. By setting the optical power of the first and second scanning beams to these empirical values, the Δδ value, which plays a decisive role in the jitter of the detuning of the first scanning beam, can be controlled. A With Δv NL They completely cancel each other out, thus enabling the optical frequency comb generating device 100 to completely eliminate the noise caused by the random variation in the optical frequency comb interval due to the jitter of the detuning amount of the first scanning beam.

[0102] In the above implementation, the addition of a first amplifier 91 and a second amplifier 92 to the optical frequency comb generating device 100 facilitates the adjustment of the optical power of the first and second scanning beams, thereby improving the functional flexibility of the optical frequency comb generating device 100. Furthermore, the first amplifier 91 and the second amplifier 92 can adjust the optical power of the first scanning beam to a first preset optical power and the optical power of the second scanning beam to a second preset optical power, thus completely eliminating the noise caused by the random variation in the optical frequency comb spacing due to the jitter of the detuning amount of the first scanning beam, which is beneficial for ensuring the narrow linewidth performance of the target optical frequency comb.

[0103] Optionally, the first amplifier 91 and the second amplifier 92 mentioned above can be optical amplifiers, such as semiconductor optical amplifiers (SOA), erbium-doped optical fiber amplifiers (EDFA), Raman fiber amplifiers (RFA), etc. This application does not limit the specific implementation of the first amplifier 91 and the second amplifier 92.

[0104] It should be noted that the optical frequency comb generating device 100 described above includes both a first amplifier 91 and a second amplifier 92. However, in an optional implementation, the optical frequency comb generating device 100 only includes the first amplifier 91, with the same location and function. In another optional implementation, when the optical power of the first scanning beam is greater than the nonlinear effect power threshold of the optical microcavity 40, the optical frequency comb generating device 100 may also include only the second amplifier 92, with the same location and function. Furthermore, in the scenario where the optical frequency comb generating device 100 includes the second amplifier 92, the second amplifier 92 can not only perform the following functions... Figure 5 The second amplifier 92 is positioned between the beam splitter 20 and the frequency shifter 30, or between the frequency shifter 30 and the circulator 60. In this case, the second amplifier 92 can be used to adjust the optical power of the third scanning beam output by the frequency shifter 30 and transmit the third scanning beam with adjusted optical power to the circulator 60. It should be understood that the above description is only based on the scenario where the optical frequency comb generating device 100 simultaneously includes the first amplifier 91 and the second amplifier 92, and the second amplifier 92 is positioned between the beam splitter 20 and the frequency shifter 30. In actual implementation, the presence of the first amplifier 91 and the second amplifier 92, and the position of the second amplifier 92, can be combined to obtain other optional implementations. This application will not list all of these optional implementations, but these optional implementations should also be within the protection scope of this application.

[0105] For some feasible implementation methods, please refer to Figure 6 , Figure 6 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 6 As shown, the optical frequency comb generating device 100 may further include a first filter 93 and a second filter 94. The first amplifier 91 is connected to a first end of the first waveguide 50 via the first filter 93 (or, one end of the first filter 93 is connected to one end of the first amplifier 91, and the other end of the first filter 93 is connected to the first end of the first waveguide 50). The second amplifier 92 is connected to the frequency shifter 30 via the second filter 94 (or, one end of the second filter 94 is connected to one end of the second amplifier 92, and the other end of the second filter 94 is connected to the first end of the frequency shifter 30).

[0106] In actual operation, the first filter 93 is used to filter out noise from the first scanning beam (i.e., the power-adjusted first scanning beam) from the first amplifier 91 and transmits the noise-filtered first scanning beam to the first waveguide 50. Here, the first filter 93 is mainly used to filter out the noise introduced by the first amplifier 91 when adjusting the power of the first scanning beam. The second filter 94 is used to filter out noise from the second scanning beam (i.e., the power-adjusted second scanning beam) from the second amplifier 92 and transmits the noise-filtered second scanning beam to the frequency shifter 30. Here, the second filter 94 is mainly used to filter out the noise introduced by the second amplifier 92 when adjusting the power of the second scanning beam.

[0107] In the above implementation, the addition of a first filter 93 and a second filter 94 to the optical frequency comb generation device can filter out the noise introduced by the power adjustment of the first and second scanning beams, thereby improving the generation efficiency of the target optical frequency comb and ensuring its stability.

[0108] Optionally, the first filter 93 and the second filter 94 mentioned above are specifically broadband noise filters, such as acousto-optic tunable filters, arrayed waveguide grating filters, Mach-Zehnder interferometer filters, etc. This application does not limit the specific implementation of the first filter 93 and the second filter 94.

[0109] It should also be noted that the above description refers to the case where the optical frequency comb generating device 100 includes both the first filter 93 and the second filter 94. In an optional implementation, the optical frequency comb generating device 100 may only include the first filter 93, with the same location and function (mainly corresponding to the scenario where the optical frequency comb generating device 100 only includes the first amplifier 91). In another optional implementation, the optical frequency comb generating device 100 may also only include the second filter 94, with the same location and function (mainly corresponding to the scenario where the optical frequency comb generating device 100 only includes the second amplifier 92). Furthermore, in the scenario where the optical frequency comb generating device 100 includes the second filter 94, when the second amplifier 92 is positioned between the frequency shifter 30 and the circulator 60, the second filter 94 may be positioned between the second amplifier 92 and the circulator 60. In this case, the second filter 94 is used to filter out noise from the third scan beam after optical power adjustment and to transmit the noise-filtered third scan beam to the circulator 60. It should be understood that the preceding description is based on the scenario where the optical frequency comb generating device 100 simultaneously includes a first filter 93 and a second filter 94, and the second filter 94 is positioned between the second amplifier 92 and the frequency shifter 30. In actual implementation, whether both the first filter 93 and the second filter 94 exist, and how the position of the second filter 94 is set, can be combined to obtain other optional implementation methods. This application will not list these optional implementation methods one by one, but these optional implementation methods should also be within the protection scope of this application.

[0110] For some feasible implementation methods, please refer to Figure 7 , Figure 7 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 7 As shown, the optical frequency comb generating device 100 also includes a first polarization controller 95 and a second polarization controller 96. The first filter 93 is connected to the first end of the first waveguide 50 via the first polarization controller 95, and the frequency shifter 30 is connected to the second end of the circulator 60 via the second polarization controller 96.

[0111] In actual operation, the first polarization controller 95 adjusts the polarization state of the first scanning beam (i.e., the filtered first scanning beam) from the first filter 93 to the target polarization state corresponding to the optical microcavity 40 (that is, adjusts the polarization state of the first scanning beam to be consistent with the working polarization state of the optical microcavity 40), and transmits the polarization-adjusted first scanning beam (i.e., the first scanning beam with the target polarization state) to the first waveguide 50. The second polarization controller 96 adjusts the polarization state of the third scanning beam (i.e., the filtered third scanning beam) from the frequency shifter 30 to the target polarization state corresponding to the optical microcavity 40 (that is, adjusts the polarization state of the third scanning beam to be consistent with the working polarization state of the optical microcavity 40), and transmits the polarization-adjusted third scanning beam (i.e., the third scanning beam with the target polarization state) to the circulator 60.

[0112] In the above implementation, a first polarization controller 95 and a second polarization controller 96 are added to the optical frequency comb generating device 100. These two devices can adjust the polarization states of the first and third scanning beams entering the optical microcavity 40, thereby ensuring that the polarization states of the first and third scanning beams are consistent with the target polarization state of the optical microcavity 40. On the one hand, this can improve the light conversion efficiency of the optical microcavity 40, thereby improving the generation efficiency of the target optical frequency comb. On the other hand, it also allows other components in the device to use non-polarization-maintaining optics, reducing the cost of the optical frequency comb generating device 100.

[0113] It should be noted that the first polarization controller 95 and the second polarization controller 96 mentioned above can be various forms of optical devices with polarization state control performance, such as glass plate polarization controllers, fiber optic ring polarization controllers, etc. This application does not impose any specific restrictions on them.

[0114] It should be noted that the above implementation describes the case where the optical frequency comb generating device 100 includes both a first polarization controller 95 and a second polarization controller 96. In an alternative implementation, the optical frequency comb generating device 100 may only include the first polarization controller 95, with the same location and function. In another alternative implementation, the optical frequency comb generating device 100 may also only include the second polarization controller 96, with the same location and function. Furthermore, in the scenario where the optical frequency comb generating device 100 includes the first polarization controller 95, the first polarization controller 95 can not only perform the following functions... Figure 7The first polarization controller 95 is positioned between the first filter 93 and the first waveguide 50, or between the first amplifier 91 and the first filter 93, or between the beam splitter 20 and the first amplifier 91. Here, the position of the first polarization controller 95 can be set according to actual application requirements, as long as it can control the polarization state of the first scanning beam before entering the optical microcavity 40. This application does not impose specific restrictions on the position of the first polarization controller 95. Similarly, in the scenario where the optical frequency comb generating device 100 includes the aforementioned second polarization controller 96, the second polarization controller 96 can not only... Figure 7 The first polarization controller 95 is positioned between the frequency shifter 30 and the circulator 60, but it can also be positioned between the second filter 94 and the frequency shifter 30, between the second amplifier 92 and the second filter 94, or between the beam splitter 20 and the second amplifier 92. The position of the second polarization controller 96 can be set according to actual application requirements, as long as it can control the polarization state of the third or second scanning beam before entering the optical microcavity 40. This application does not impose specific restrictions on the position of the second polarization controller 96. Therefore, in actual implementation, whether both the first polarization controller 95 and the second polarization controller 96 exist, and how their positions are set, can be combined to obtain various other optional implementations. This application will not list all these optional implementations, but they should also be within the scope of protection of this application.

[0115] It should be understood that Figure 7 The description of the functions of the first polarization controller 95 and the second polarizer 96 uses an example scenario where the optical frequency comb generating device 100 includes a first amplifier 91, a second amplifier 92, a first filter 93, and a second filter 94. However, in another optional implementation, the optical frequency comb generating device 100 may only include the aforementioned first polarization controller 95 and second polarization controller 96. For example, please refer to... Figure 8 , Figure 8 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 8As shown, the optical frequency comb generating device 100 does not include the first amplifier 91, the second amplifier 92, the first filter 93, and the second filter 94; it only includes a first polarization controller 95 and a second polarization controller 96. One end of the first polarization controller 95 is connected to the beam splitter 20, and the other end is connected to the first waveguide 50. It is used to adjust the polarization state of the first scanning beam output from the beam splitter 20 to the target polarization state corresponding to the optical microcavity 40. The second polarization controller 96 is disposed between the frequency shifter 30 and the circulator 60, and is used to adjust the polarization state of the third scanning beam to the target polarization state corresponding to the optical microcavity 40. Alternatively, the second polarization controller 96 can also be disposed between the beam splitter 20 and the frequency shifter 30, and used to adjust the polarization state of the second scanning beam to the target polarization state corresponding to the optical microcavity 40.

[0116] In some feasible implementations, as mentioned above, when the controller 80 determines through the detector 70 that the beam output from the third end of the circulator 60 is the target beam, it controls the laser 10 to stop changing the frequency of the source scanning beam and controls the frequency shifter 30 to stop changing the frequency of the third scanning beam. Although the optical frequency comb generating device 100 has generated the target optical frequency comb, some external environmental factors (such as changes in the ambient temperature of the optical frequency comb generating device 100) can easily cause changes in the beam output by the optical frequency comb generating device 100, that is, it can easily cause the optical frequency comb generating device 100 to no longer generate the narrow linewidth target optical frequency comb.

[0117] Therefore, to address the stability issue of the target optical frequency comb, when the optical microcavity 40 generates the target beam, the aforementioned detector can also be used to detect the target beam output from the third end of the circulator 60 to obtain the optical power of the target beam, and feed the optical power of the target beam back to the controller 80. The controller 80 can receive and store the optical power of the target beam. Then, the detector 70 can continue to detect the optical power of the beam output from the third end of the circulator 60 and feed the optical power of the beam output from the third end of the circulator 60 back to the controller 80. The controller 80 is used to determine whether the optical power of the beam output from the third end of the circulator 60 has changed (that is, to determine whether the beam output from the third end of the circulator 60 is still the target beam) based on the optical power fed back by the detector 70 and its pre-stored optical power of the target beam. Specifically, the controller 80 can compare the optical power of the beam output from the third end of the circulator 60 subsequently detected by the detector 70 with the optical power of the target beam. If the controller 80 determines that the optical power of the beam output from the third end of the circulator 60 is not equal to the optical power of the target beam, or if the controller 80 determines that the difference between the optical power of the beam output from the third end of the circulator 60 and the optical power of the target beam is greater than a preset deviation value, then it can be determined that the optical power of the beam output from the third end of the circulator 60 has changed, and thus it can be determined that the beam output from the third end of the circulator 60 is no longer the target beam. Then, the controller 80 can also control the frequency shifter 30 to change the frequency of the third scanning beam again until the optical power of the beam output from the third end of the circulator 60 recovers to the optical power of the target beam (or, until it is confirmed that the beam output from the third end of the circulator 60 is again the target beam). Specifically, the controller 80 can control the frequency shifter 30 to gradually increase the frequency of the third scanning beam. During this process, the detector 70 continuously detects and feeds back the optical power of the beam output from the third end of the circulator 60 to the controller 80. The controller 80 then determines whether the optical power of the beam output from the third end of the circulator 60 has recovered to the optical power of the target beam based on the optical power fed back by the detector 70. If the controller 80 determines that the optical power of the beam output from the third end of the circulator 60 has recovered to the optical power of the target beam, it can control the frequency shifter 30 to stop the frequency change of the third scanning beam again. If, after a period of time, the controller 80 determines that the optical power of the beam output from the third end of the circulator 60 still cannot recover to the optical power of the target beam, the controller 80 can control the frequency shifter 30 to gradually reduce the frequency of the third scanning beam, and during this process, the detector 70 continues to determine whether the optical power of the beam output from the third end of the circulator 60 has recovered to the optical power of the target beam. If, at a certain moment, it is determined that the optical power of the beam output from the third end of the circulator 60 has recovered to the optical power of the target beam, the frequency shifter 30 can be controlled again to stop the frequency change of the third scanning beam.

[0118] In the above implementation, when the optical power of the beam output from the third end of the circulator 60 changes (i.e. it is no longer the optical power of the target beam), the frequency shifter 30 can be controlled by the controller 80 to change the frequency of the third scanning beam, so that the optical power of the beam output from the third end of the circulator 60 is restored to the optical power of the target beam. This ensures that the optical frequency comb generating device 100 can continuously and stably output the target optical frequency comb, thereby improving the applicability of the optical frequency comb generating device 100.

[0119] For some feasible implementation methods, please refer to Figure 9 , Figure 9 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. It should be understood that... Figure 9 The optical microcavity 40 is also shown in the form of a microring. For example... Figure 9 As shown, the optical frequency comb generating device includes not only the laser 10, beam splitter 20, frequency shifter 30, and optical microcavity 40 mentioned above, but also a second waveguide 110 and a third waveguide 120. The first end of the beam splitter 20 is connected to the laser 10, and the second end of the beam splitter 20 is connected to the first end of the second waveguide 110. The optical microcavity 40 is coupled between the first and second ends of the second waveguide 110 (or, the optical microcavity 40 is positioned close to the second waveguide 110, but they are close but not in contact, with a certain distance between them). The third end of the beam splitter 20 is connected to the first end of the frequency shifter 30, and the second end of the frequency shifter 30 is connected to the first end of the third waveguide 120. The optical microcavity 40 is also simultaneously coupled between the first and second ends of the third waveguide 120 (or, the optical microcavity 40 is positioned close to the third waveguide 120, but they are close but not in contact, with a certain distance between them). Optionally, both the second waveguide 110 and the third waveguide 120 mentioned above are straight waveguides.

[0120] In actual operation, the second waveguide 110 is used to transmit the first scanning beam to the optical microcavity 40, and the third waveguide 120 is used to transmit the third scanning beam to the optical microcavity 40. When the optical microcavity 40 outputs a target beam, the third port of the second waveguide 110 is also used to output the target beam. Specifically, the beam splitter 20 can emit the first scanning beam to the second waveguide 110 through its second end. The second waveguide 110 can receive the first scanning beam through its first end. During the transmission of the first scanning beam from the first end to the second end of the second waveguide 110, when it passes near the optical microcavity 40, the first scanning beam can couple to the optical microcavity 40 and be conducted therein. Simultaneously, the frequency shifter 30 can emit the third scanning beam through its second port, the third waveguide 120. The third waveguide 120 can receive the third scanning beam through its first end. During the transmission of the third scanning beam from the first end to the second end of the third waveguide 120, when it passes near the optical microcavity 40, the third scanning beam can couple to the optical microcavity 40 and be conducted therein. Here, as mentioned earlier, the first and third scanning beams propagate in opposite directions within the optical microcavity 40. Furthermore, when the first scanning beam is in the red detuning region of the optical microcavity 40 and the third scanning beam is in the blue detuning region, the optical microcavity 40 can generate and output a target beam with the spectrum of the target optical frequency comb. This target beam is coupled from the optical microcavity 40 to the second waveguide 110 and ultimately output from the second port of the second waveguide 110. The functions of the laser 10, beam splitter 20, frequency shifter 30, and optical microcavity 40 are described above and will not be repeated here.

[0121] In the above implementation, the input of the first scanning beam and the third scanning beam to the optical microcavity 40 and the output of the target beam from the optical microcavity 40 are realized through the second waveguide 110 and the third waveguide 120. The scheme is simple and low cost. It can reduce the structural complexity of the optical frequency comb generating device 100 and also reduce the cost of the optical frequency comb generating device 100.

[0122] In some feasible implementation methods, Figure 9 Based on the structure shown, please refer to Figure 10 , Figure 10 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 10 As shown, the optical frequency comb generating device 100 should also include a detector 70 and a controller 80. The detector 70 is connected to the second end of the second waveguide 110, and the controller 80 is connected to the laser 10, the frequency shifter 30, and the detector 70.

[0123] In actual operation, controller 80 is used to control laser 10 to generate and output a source scanning beam via a first control signal. Controller 80 is also used to control frequency shifter 30 to generate and output a third scanning beam based on the second scanning beam via a second control signal. The specific process is described in the preceding text and will not be repeated here.

[0124] Furthermore, the detector 70 is used to detect the beam output from the second end of the second waveguide 110. Specifically, the detector 70 can detect the spectrum of the beam output from the second end of the second waveguide 110 and send the detected spectrum to the controller 80. After receiving the spectrum from the detector 70, the controller 80 can analyze the spectrum to determine whether the spectrum is the target optical frequency comb (that is, whether the beam output from the second end of the second waveguide 110 is the target beam). Here, the specific process by which the controller 80 determines whether the beam output from the second end of the second waveguide 110 is the target beam based on the spectrum detected by the detector 70 is similar to the process described above of the controller 80 determining whether the beam output from the third end of the circulator 60 is the target beam based on the spectrum detected by the detector 70, so it can be referred to the above. When the controller 80 determines that the beam output from the second end of the second waveguide 110 is the target beam, it can control the laser 10 to stop the frequency change of the source scanning beam through the third control signal. At the same time, the controller 80 can also control the frequency shifter 30 to stop the frequency change of the second scanning beam through the fourth control signal. If the controller 80 determines, after analysis, that the beam output from the second end of the second waveguide 110 is not the target beam, the controller 80 can continue to control the laser 10 to generate the aforementioned source scanning beam, and continue to control the frequency shifter 30 to generate the aforementioned third scanning beam.

[0125] For some feasible implementation methods, please refer to Figure 11 , Figure 11 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 11 As shown, the optical frequency comb generating device 100 may further include a first amplifier 91 and a second amplifier 92. The second end of the beam splitter 20 is connected to the first end of the second waveguide 110 via the first amplifier 91. The third end of the beam splitter 20 is connected to the first end of the frequency shifter 30 via the second amplifier 92.

[0126] In actual operation, the first amplifier 91 is used to adjust the optical power of the first scanning beam and transmit the first scanning beam with adjusted optical power to the second waveguide 110. Here, the optical power of the first scanning beam with adjusted optical power must be equal to or greater than the nonlinear effect power threshold of the optical microcavity 40. The second amplifier 92 is used to adjust the optical power of the second scanning beam and transmit the second scanning beam with adjusted optical power to the frequency shifter 30. For example, the first amplifier 91 can be used to adjust the optical power of the first scanning beam to a first preset optical power and transmit the first scanning beam with the first preset optical power to the second waveguide 110. Here, the first preset optical power is equal to or greater than the nonlinear effect power threshold corresponding to the optical microcavity 40. The second amplifier 92 can be used to adjust the optical power of the second scanning beam to a second preset optical power and transmit the second scanning beam with the second preset optical power to the frequency shifter 30, so that the optical power of the third scanning beam that subsequently enters the optical microcavity 40 is the second preset optical power. Here, the explanation of the first preset optical power and the second preset optical power can be found in the preceding text. By setting the optical power of the first and second scanning beams to a preset optical power, the Δδ, which plays a decisive role in the jitter of the detuning of the first scanning beam, can be controlled. A With Δv NL They completely cancel each other out, thus enabling the optical frequency comb generating device 100 to completely eliminate the noise caused by the random variation in the optical frequency comb interval due to the jitter of the detuning amount of the first scanning beam.

[0127] In the above implementation, the addition of a first amplifier 91 and a second amplifier 92 to the optical frequency comb generating device 100 facilitates the adjustment of the optical power of the first and second scanning beams, enhancing the functional flexibility of the optical frequency comb generating device 100. Furthermore, the first amplifier 91 and the second amplifier 92 can adjust the optical power of the first scanning beam to a first preset optical power and the optical power of the second scanning beam to a second preset optical power, thereby completely eliminating the noise caused by the random variation in the optical frequency comb spacing due to the jitter of the detuning amount of the first scanning beam, which is beneficial for ensuring the narrow linewidth performance of the target optical frequency comb.

[0128] The specific implementations of the first amplifier 91 and the second amplifier 92 can be found in the preceding text, and will not be repeated here.

[0129] Similar to the previous example, the above implementation uses a scenario where the optical frequency comb generating device 100 includes both a first amplifier 91 and a second amplifier 92. However, in actual implementation, the optical frequency comb generating device 100 may also include only one of the first amplifier 91 and the second amplifier 92. Furthermore, in the scenario where the optical frequency comb generating device 100 includes the aforementioned second amplifier 92, this second amplifier 92 can not only... Figure 11The second amplifier 92 is positioned between the beam splitter 20 and the frequency shifter 30, and can also be positioned between the frequency shifter 30 and the third waveguide 120. In this case, the second amplifier 92 is mainly used to adjust the optical power of the third scanning beam output by the frequency shifter 30 and to transmit the third scanning beam with adjusted optical power to the third waveguide 120. It should be understood that in actual implementation, the presence of the first amplifier 91 and the second amplifier 92, and the position of the second amplifier 92, can be combined to obtain other optional implementations. This application will not list all of these optional implementations, but these optional implementations should also be within the protection scope of this application.

[0130] For some feasible implementation methods, please refer to Figure 12 , Figure 12 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 12 As shown, the optical frequency comb generating device 100 may further include a first filter 93 and a second filter 94. The first amplifier 91 is connected to the first end of the second waveguide 110 via the first filter 93, and the second amplifier 92 is connected to the frequency shifter 30 via the second filter 94. In actual operation, the first filter 93 is used to filter out noise from the first scanning beam from the first amplifier 91 and transmit the noise-filtered first scanning beam to the second waveguide 110. The second filter 94 is used to filter out noise from the second scanning beam from the second amplifier 92 and transmit the noise-filtered second scanning beam to the frequency shifter 30.

[0131] In the above implementation, the addition of a first filter 93 and a second filter 94 to the optical frequency comb generation device can filter out the noise introduced by the power adjustment of the first and second scanning beams, thereby improving the generation efficiency of the target optical frequency comb and ensuring its stability.

[0132] For a detailed explanation of the first filter 93 and the second filter 94, please refer to the previous text; it will not be repeated here.

[0133] It should also be noted that the above implementation is described assuming that the optical frequency comb generating device 100 includes both the first filter 93 and the second filter 94. In actual implementation, the optical frequency comb generating device 100 may include only one of the first filter 93 and the second filter 94. Preferably, the presence of a first amplifier 91 corresponds to the presence of a first filter 93, and the presence of a second amplifier 92 corresponds to the presence of a second filter 94. Furthermore, in the scenario where the optical frequency comb generating device 100 includes the second filter 94, when the second amplifier 92 is positioned between the frequency shifter 30 and the third waveguide 120, the second filter 94 may be positioned between the second amplifier 92 and the third waveguide 120. In this case, the second filter 94 is used to filter noise from the third scanning beam and transmit the noise-filtered third scanning beam to the third waveguide 120. It should be understood that in actual implementation, whether the first filter 93 and the second filter 94 both exist, and how the position of the second filter 94 is set, can be combined to obtain other optional implementation methods. This application will not list these optional implementation methods one by one, but these optional implementation methods should also be within the protection scope of this application.

[0134] For some feasible implementation methods, please refer to Figure 13 , Figure 13 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 13 As shown, the optical frequency comb generating device 100 also includes a first polarization controller 95 and a second polarization controller 96. The first filter 93 is connected to the first end of the second waveguide 110 via the first polarization controller 95, and the frequency shifter 30 is connected to the first end of the third waveguide 120 via the second polarization controller 96. In actual operation, the first polarization controller 95 is used to adjust the polarization state of the first scanning beam from the first filter 93 to the target polarization state corresponding to the optical microcavity 40. The second polarization controller 96 is used to adjust the polarization state of the third scanning beam from the frequency shifter 30 to the target polarization state corresponding to the optical microcavity 40.

[0135] In the above implementation, a first polarization controller 95 and a second polarization controller 96 are added to the optical frequency comb generating device 100. These two devices can adjust the polarization states of the first and third scanning beams entering the optical microcavity 40, thereby ensuring that the polarization states of the first and third scanning beams are consistent with the target polarization state of the optical microcavity 40. On the one hand, this can improve the light conversion efficiency of the optical microcavity 40, thereby improving the generation efficiency of the target optical frequency comb. On the other hand, it also allows other components in the device to use non-polarization-maintaining optics, reducing the cost of the optical frequency comb generating device 100.

[0136] For selection instructions regarding the first polarization controller 95 and the second polarization controller 96, please refer to the previous text; they will not be repeated here.

[0137] It should be noted that the above implementation is based on the example where the optical frequency comb generating device 100 includes both a first polarization controller 95 and a second polarization controller 96. In actual implementation, the optical frequency comb generating device 100 may also include only one of the first polarization controller 95 and the second polarization controller 96. Furthermore, in the scenario where the optical frequency comb generating device 100 includes the aforementioned first polarization controller 95, this first polarization controller 95 can not only... Figure 13 The second polarization controller 96 is positioned between the first filter 93 and the second waveguide 110, as shown. It can also be positioned between the first amplifier 91 and the first filter 93, or between the beam splitter 20 and the first amplifier 91, as long as it can control the polarization state of the first scanning beam before it enters the optical microcavity 40. Similarly, in a scenario where the optical frequency comb generating device 100 includes the aforementioned second polarization controller 96, this second polarization controller 96 can not only... Figure 13 The polarization controller 95 is positioned between the frequency shifter 30 and the second waveguide 120, or between the second filter 94 and the frequency shifter 30, or between the second amplifier 92 and the second filter 94, or between the beam splitter 20 and the second amplifier 92, as long as it can control the polarization state of the third scanning beam or the second scanning beam before entering the optical microcavity 40. It should be understood that in actual implementation, the presence of both the first polarization controller 95 and the second polarization controller 96, and their respective positions, can lead to various other optional implementations. This application will not list all of these optional implementations, but they should also be within the scope of protection of this application.

[0138] It should be understood that Figure 13 The description of the functions of the first polarization controller 95 and the second polarization controller 96 is based on an example scenario where the optical frequency comb generating device 100 includes a first amplifier 91, a second amplifier 92, a first filter 93, and a second filter 94. However, in an alternative implementation, the optical frequency comb generating device 100 may only include the aforementioned first polarization controller 95 and second polarization controller 96. For example, please refer to... Figure 14 , Figure 14 This is another structural schematic diagram of the optical frequency comb generating device provided in the embodiments of this application. For example... Figure 14As shown, the optical frequency comb generating device 100 does not include the first amplifier 91, the second amplifier 92, the first filter 93, and the second filter 94; it only includes a first polarization controller 95 and a second polarization controller 96. One end of the first polarization controller 95 is connected to the beam splitter 20, and the other end is connected to the second waveguide 110. It is used to adjust the polarization state of the first scanning beam output from the beam splitter 20 to the target polarization state corresponding to the optical microcavity 40. The second polarization controller 96 is disposed between the frequency shifter 30 and the third waveguide 120, and is used to adjust the polarization state of the third scanning beam to the target polarization state corresponding to the optical microcavity 40. Alternatively, the second polarization controller 96 can also be disposed between the beam splitter 20 and the frequency shifter 30, and used to adjust the polarization state of the second scanning beam to the target polarization state corresponding to the optical microcavity 40.

[0139] In some feasible implementation methods, Figures 9-14 Based on the structure shown, to address the stability issue of the target optical frequency comb, similarly, when the optical microcavity 40 generates the target beam, the detector can also be used to detect the target beam output from the second end of the second waveguide 110 to obtain the optical power of the target beam, and feed the optical power of the target beam back to the controller 80. The controller 80 can receive and store the optical power of the target beam. Then, the detector 70 can continue to detect the optical power of the beam output from the second end of the second waveguide 110 and feed the detected optical power back to the controller 80. The controller 80 is used to determine whether the optical power of the beam output from the second end of the second waveguide 110 has changed (that is, to determine whether the beam output from the second end of the second waveguide 110 is still the target beam) based on the optical power fed back by the detector 70 and its pre-stored optical power of the target beam. For the specific process, please refer to the process described above where the controller 80 determines whether the optical power of the beam output from the third end of the circulator 60 has changed based on the optical power fed back by the detector 70 and its pre-stored optical power of the target beam, which will not be repeated here. Then, when it is determined that the optical power of the beam output from the second end of the second waveguide 110 has changed, the controller 80 is also used to control the frequency shifter 30 to change the frequency of the third scanning beam again, until the optical power of the beam output from the second end of the second waveguide 110 recovers to the optical power of the target beam (or, until it is confirmed again that the beam output from the second end of the second waveguide 110 is the target beam). The specific process can be referred to in the above description of "the controller 80 controls the frequency shifter 30 to change the frequency of the third scanning beam again, until the optical power of the beam output from the third end of the circulator 60 recovers to the optical power of the target beam", which will not be repeated here.

[0140] In the above implementation, when the optical power of the beam output from the second end of the second waveguide 110 changes (i.e. it is no longer the optical power of the target beam), the frequency of the third scanning beam can be changed by controlling the frequency shifter 30 through the controller 80, so that the optical power of the beam output from the second end of the second waveguide 110 is restored to the optical power of the target beam. This ensures that the optical frequency comb generating device 100 can continuously and stably output the target optical frequency comb, thereby improving the applicability of the optical frequency comb generating device 100.

[0141] In some feasible implementations, the laser 10 described above can be a sub-Hertz linewidth laser, which allows the linewidth of the target optical frequency comb output by the optical frequency comb generating device 100 to be maintained in the sub-Hertz range. Here, sub-Hertz refers to the range of 0 to 1 Hz.

[0142] It should be noted that, in certain applications, the first scanning beam mentioned above can also be referred to as the pump beam, and the third scanning beam mentioned above can also be referred to as the auxiliary beam. The optical frequency comb generated by the optical microcavity 40 can also be referred to as the Kerr optical frequency comb, and the aforementioned target optical frequency comb can also be referred to as the dissipative soliton mode-locked Kerr optical comb.

[0143] It should also be noted that the connections between the devices mentioned above can include physical optical connections or spatial optical connections, such as optical connections established through waveguides or other optical transmission devices, or optical connections established through spatial optical fields. For example, the laser 10 and beam splitter 20 can be connected through spatial optical fields or optical fibers. Furthermore, the connections between the devices mentioned above can also include electrical connections, such as the electrical connection between the controller 80 and the laser 10, to achieve the transmission of electrical signals between them. The specific connection method between the devices can be determined by the actual transmission requirements of each device, and this application does not impose any restrictions on this.

[0144] Example 2

[0145] Please see Figure 15 , Figure 15 This is a schematic flowchart of the optical frequency comb generation method provided in this application embodiment. This optical frequency comb generation method is applicable to the optical frequency comb generation device 100 described in Embodiment 1 above. In this embodiment, the specific structure and function of the optical frequency comb generation device 100 can be found in the corresponding description in Embodiment 1 above, and will not be repeated here. Figure 15 As shown, the coherent light receiving method specifically includes the following steps:

[0146] S151. A source scanning beam with a frequency varying in a first direction is generated by a laser, and the source scanning beam is emitted to a beam splitter.

[0147] In some feasible implementations, the optical frequency comb generating device 100 can generate a source scanning beam with a frequency varying in a first direction via the laser 10 and transmit the source scanning beam to the beam splitter 20. Specifically, the optical frequency comb generating device 100 can control the laser 10 to generate the aforementioned source scanning beam by transmitting a first control signal to the laser 10 via its included controller 80. The specific control process can be found in the process described in Embodiment 1 above, where the controller 80 controls the laser 10 to generate the source scanning beam, and will not be repeated here.

[0148] S152. The source scanning beam is split into a first scanning beam and a second scanning beam by a beam splitter. The first scanning beam is emitted into the optical microcavity, and the second scanning beam is emitted into the frequency shifter.

[0149] In some feasible implementations, after receiving the source scanning beam, the beam splitter 20 can decompose the source scanning beam into a first scanning beam and a second scanning beam. Then, it emits the first scanning beam to the optical microcavity 40 and the second scanning beam to the frequency shifter 30. The optical power of the first scanning beam must be equal to or greater than the nonlinear effect power threshold of the optical microcavity 40. The specific process of the beam splitter 20 decomposing and emitting the first and second scanning beams can be found in Embodiment 1, and will not be repeated here.

[0150] In one alternative implementation, the optical frequency comb generating device 100 employs... Figure 3 In the scenario shown, the optical frequency comb generating device 100 specifically emits a first scanning beam to the optical microcavity 40 via the first waveguide 50. The process of emitting the first scanning beam to the optical microcavity 40 via the first waveguide 50 is described in the preceding text and will not be repeated here. Simultaneously, the optical frequency comb generating device 100 also emits a third scanning beam to the optical microcavity 40 via the first waveguide 50 and the circulator 60; the specific process is described in the preceding text and will not be repeated here.

[0151] Furthermore, in the case where the optical frequency comb generating device 100 also includes a first amplifier 91 and a second amplifier 92, the optical frequency comb generating device 100 can adjust the optical power of the first scanning beam from the beam splitter 20 through the first amplifier 91, and then transmit the first scanning beam with adjusted optical power to the first waveguide 50. Here, the optical power of the first scanning beam with adjusted optical power is equal to or greater than the nonlinear effect power threshold of the optical microcavity 40. In addition, the optical frequency comb generating device 100 can also adjust the optical power of the second scanning beam from the beam splitter 20 through the second amplifier 92, and then transmit the second scanning beam with adjusted optical power to the frequency shifter 30. Here, the specific process of adjusting the optical power of the first scanning beam through the first amplifier 91 and adjusting the optical power of the second scanning beam through the second amplifier 92 can be found in the description of the functions of the first amplifier 91 and the second amplifier 92 in Embodiment 1, and will not be repeated here.

[0152] Furthermore, when the optical frequency comb generating device 100 also includes a first filter 93 and a second filter 94, the optical frequency comb generating device 100 can use the first filter 93 to filter out noise from the first scanning beam after adjusting the optical power output of the first amplifier 91, and then transmit the noise-filtered first scanning beam to the first waveguide 50. In addition, the optical frequency comb generating device 100 can also use the second filter 94 to filter out noise from the second scanning beam after adjusting the optical power output of the second amplifier 92, and then transmit the noise-filtered second scanning beam to the frequency shifter 30. Here, the specific processes of filtering out noise from the first scanning beam using the first filter 93 and filtering out noise from the second scanning beam using the second filter 94 can be found in the description of the functions of the first filter 93 and the second filter 94 in Embodiment 1, and will not be repeated here.

[0153] Furthermore, if the optical frequency comb generating device 100 also includes a first polarization controller 95, the optical frequency comb generating device 100 can first adjust the polarization state of the first scanning beam after noise filtering to the target polarization state of the optical microcavity 40 through the first polarization controller 95, and then emit the first scanning beam with adjusted polarization state to the first waveguide 50. For details, please refer to the description of the function of the first polarization controller 95 in Embodiment 1, which will not be repeated here.

[0154] In another alternative implementation, the optical frequency comb generating device 100 employs... Figure 9 In the scenario shown, the optical frequency comb generating device 100 specifically emits a first scanning beam to the optical microcavity 40 via the second waveguide 110. Furthermore, the optical frequency comb generating device 100 also emits a third scanning beam to the optical microcavity 40 via the third waveguide 120. For details, please refer to the corresponding process described in Embodiment 1, which will not be repeated here.

[0155] Furthermore, in the case where the optical frequency comb generating device 100 also includes a first amplifier 91 and a second amplifier 92, the optical frequency comb generating device 100 can adjust the optical power of the first scanning beam through the first amplifier 91, and then transmit the first scanning beam with adjusted optical power to the second waveguide 110. The optical power of the first scanning beam with adjusted optical power is equal to or greater than the nonlinear effect power threshold of the optical microcavity 40. Simultaneously, the optical frequency comb generating device 100 can also adjust the optical power of the second scanning beam through the second amplifier 92, and then transmit the second scanning beam with adjusted optical power to the frequency shifter 30. For a detailed description of the functions of the first amplifier 91 and the second amplifier 92 in Embodiment 1 above, it will not be repeated here.

[0156] Furthermore, if the optical frequency comb generating device 100 also includes a first filter 93 and a second filter 94, the optical frequency comb generating device 100 can first filter out noise from the first scan beam after adjusting the optical power using the first filter 93, and then transmit the noise-filtered first scan beam to the second waveguide 110. Simultaneously, the optical frequency comb generating device 100 can also first filter out noise from the second scan beam after adjusting the optical power using the second filter 94, and then transmit the noise-filtered second scan beam to the frequency shifter 30. For details, please refer to the description of the functions of the first filter 93 and the second filter 94 in Embodiment 1 above, which will not be repeated here.

[0157] Furthermore, if the optical frequency comb generating device 100 also includes a first polarization controller 95, the optical frequency comb generating device 100 can adjust the polarization state of the noise-filtered first scanning beam to the target polarization state of the optical microcavity 40 through the first polarization controller 95, and then emit the polarization-adjusted first scanning beam into the second waveguide 110. For details, please refer to the description of the function of the first polarization controller 95 in Embodiment 1 above, which will not be repeated here.

[0158] S153. A third scanning beam with a frequency varying in a second direction is generated based on the second describing beam using a frequency shifter, and the third scanning beam is sent to the optical microcavity.

[0159] In some feasible implementations, after acquiring the second scanning beam, the optical frequency comb generating device 100 can also generate a third scanning beam with a frequency varying in a second direction based on the second describing beam using a frequency shifter 30. The specific process of generating the third scanning beam based on the second describing beam using the frequency shifter 30 can be found in the description of the process in Embodiment 1, and will not be repeated here.

[0160] After acquiring the third scanning beam, the optical frequency comb generating device 100 can send the third scanning beam to the optical microcavity 40 through the frequency shifter 30.

[0161] Optionally, the optical frequency comb generating device 100 adopts... Figure 3 In the case of the structure shown, which also includes a second polarization controller 96, the optical frequency comb generating device 100 can first adjust the polarization state of the third scanning beam to the target polarization state through the second polarization controller 96, and then emit the polarization-adjusted third scanning beam into the optical microcavity 40 through the circulator 60. For a specific process, please refer to Embodiment 1, where the optical frequency comb generating device 100 employs... Figure 3 The description of the function of the second polarization controller 96, as shown in the diagram, will not be repeated here.

[0162] Optionally, the optical frequency comb generating device 100 adopts... Figure 9 In the case of the structure shown, which also includes a second polarization controller 96, the optical frequency comb generating device 100 can first adjust the polarization state of the third scanning beam to the target polarization state through the second polarization controller 96, and then emit the polarization-adjusted third scanning beam to the optical microcavity 40 through the third waveguide 120. For a specific process, please refer to Embodiment 1, where the optical frequency comb generating device 100 employs... Figure 9 The description of the function of the second polarization controller 96, as shown in the diagram, will not be repeated here.

[0163] S154. A target beam is generated by means of an optical microcavity when the first scanning beam is in the red detuning region of the optical microcavity and the third scanning beam is in the blue detuning region of the optical microcavity.

[0164] In some feasible implementations, the optical frequency comb generating device 100 can continuously receive the first and third scanning beams through the optical microcavity 40. Then, over time, the first scanning beam will be in the red detuning region of the optical microcavity 40, and the third scanning beam will be in the blue detuning region of the optical microcavity 40. In this case, the optical frequency comb generating device 100 can generate and output the target beam through the optical microcavity 40. Here, the spectrum of the target beam is the desired target optical frequency comb. The process of the optical frequency comb generating device 100 generating the target beam through the optical microcavity 40 can be found in the description of the process of generating the target beam through the optical microcavity 40 in Embodiment 1 above, and will not be repeated here.

[0165] In one alternative implementation, the optical frequency comb generating device 100 employs... Figure 3In the scenario shown, after determining that the beam output from the third end of the circulator 60 is the target beam, the optical frequency comb generating device 100 can further determine whether the optical power of the beam output from the third end of the circulator 60 has changed through the detector 70 and the controller 80. The specific process can be found in the description of the process by which the detector 70 and controller 80 determine whether the optical power of the beam output from the third end of the circulator 60 has changed, as described in Embodiment 1 above, and will not be repeated here. When it is determined that the optical power of the beam output from the third end of the circulator 60 has changed, the controller 80 controls the frequency shifter 30 to change the frequency of the third scanning beam until the optical power of the beam output from the third end of the circulator 60 recovers to the optical power of the target beam. The specific process can be found in the corresponding process described in Embodiment 1 above, and will not be repeated here.

[0166] In another alternative implementation, the optical frequency comb generating device 100 employs... Figure 9 In the scenario shown, after determining that the beam output from the second end of the second waveguide 110 is the target beam, the optical frequency comb generating device 100 can further determine whether the optical power of the beam output from the second end of the second waveguide 110 has changed through the detector 70 and the controller 80. The specific process can be found in the description of the process by which the detector 70 and controller 80 determine whether the optical power of the beam output from the second end of the second waveguide 110 has changed, as described in Embodiment 1 above, and will not be repeated here. When it is determined that the optical power of the beam output from the second end of the second waveguide 110 has changed, the controller 80 controls the frequency shifter 30 to change the frequency of the third scanning beam until the optical power of the beam output from the second end of the second waveguide 110 recovers to the optical power of the target beam. The specific process can be found in the corresponding process described in Embodiment 1 above, and will not be repeated here.

[0167] In the optical frequency comb generation method provided in this application, the optical microcavity 40 is scanned simultaneously by a first scanning beam and a third scanning beam of the same origin. This reduces or eliminates three types of noise: random variation of the optical frequency comb interval caused by the detuning of the first scanning beam, frequency jitter of the optical frequency comb caused by the frequency jitter of the laser 10, and frequency jitter of the optical frequency comb caused by the resonant frequency. This results in a target optical frequency comb with a very narrow linewidth, which improves the applicability and practicality of the optical frequency comb generation method.

[0168] This application also provides a light emitting device. See [link to application]. Figure 16 , Figure 16 This is a schematic diagram of the structure of a light emitting device provided in an embodiment of this application. For example... Figure 16As shown, the optical emitting device 200 may include the optical frequency comb generating device 100 and the optical signal processor 300 described above. The optical frequency comb generating device 100 is connected to the optical signal processor 300. In actual operation, the optical frequency comb generating device 100 serves as the light source for the optical emitting device 200, generating and transmitting a target beam to the optical signal processor 300. The optical signal processor 300 receives the target beam, modulates it, and then obtains and outputs the corresponding target signal light.

[0169] It should be noted that, Figure 16 Only two functional devices included in the optical transmitting device 200 are shown: the optical frequency comb generating device 100 and the optical signal processor 300. In actual implementation, the optical transmitting device 200 may also include other devices such as a power supply, a microprocessor, and an analog-to-digital converter (ADC). This application does not limit the specific structure of the optical transmitting device 200.

[0170] In practical applications, the aforementioned optical transmitting device 200 can specifically be an optical transmitter in a coherent optical communication system or an integrated light source in a lidar system. This application does not limit the product form of the optical transmitting device 200. The optical signal processor 300 can specifically be a digital signal processor, or other types of processors. For example, general-purpose processors, application-specific integrated circuits, field-programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components; this application does not limit these.

[0171] This application also provides an optical communication system. Please refer to [link to relevant documentation]. Figure 17 , Figure 17 This is a schematic diagram of the structure of an optical communication system provided in an embodiment of this application. For example... Figure 17 As shown, the optical communication system 700 may include the optical transmitting device 200 and the optical receiving device 500 described above. The optical transmitting device 200 and the optical receiving device 500 are connected. In actual operation, the optical transmitting device 200 generates a target signal light based on the target beam generated by the optical frequency comb generating device 100 and the data to be transmitted, and transmits the target signal light to the optical receiving device 500. The optical receiving device 500 receives the target signal light and processes it to obtain the data to be transmitted.

[0172] It should be understood that in practical applications, the aforementioned optical communication system 700 can be a coherent optical communication system or other types of optical communication systems, and this application does not impose any specific restrictions on it.

[0173] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, or methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0174] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0175] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0176] The terms "first," "second," "third," and "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0177] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0178] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in this application can be implemented using hardware, software, firmware, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein communication media include any medium that facilitates the transfer of a computer program from one place to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer.

[0179] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above description is only a specific embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solution of this application should be included within the scope of protection of this application.

Claims

1. An optical frequency comb generating device, characterized in that, The device includes a laser, a beam splitter, a frequency shifter, and an optical microcavity; The laser is used to generate a source scanning beam with a frequency varying in a first direction, and to emit the source scanning beam toward the beam splitter; The beam splitter is used to decompose the source scanning beam into a first scanning beam and a second scanning beam, emit the first scanning beam to the optical microcavity, and emit the second scanning beam to the frequency shifter, wherein the optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold of the optical microcavity. The frequency shifter is used to change the frequency of the second scanning beam to generate a third scanning beam with a frequency that varies in a second direction, and to emit the third scanning beam into the optical microcavity; The optical microcavity is used to generate a target beam when the first scanning beam is in the red detuning region of the optical microcavity and the third scanning beam is in the blue detuning region of the optical microcavity, wherein the spectrum of the target beam is a target optical frequency comb.

2. The device according to claim 1, characterized in that, The first scanning beam and the third scanning beam have opposite transmission directions in the optical microcavity.

3. The device according to claim 2, characterized in that, The frequency change rate of the third scanning beam is equal to or greater than the frequency change rate of the first scanning beam.

4. The device according to any one of claims 1-3, characterized in that, The device also includes a first waveguide and a circulator; The first end of the beam splitter is connected to the laser, the second end of the beam splitter is connected to the first end of the first waveguide, the second end of the first waveguide is connected to the first end of the circulator, and the optical microcavity is coupled between the first end and the second end of the first waveguide. The third end of the beam splitter is connected to the first end of the frequency shifter, and the second end of the frequency shifter is connected to the second end of the circulator; The first waveguide is used to transmit the first scanning beam to the optical microcavity, the first waveguide and the circulator are used to transmit the third scanning beam to the optical microcavity, and the third port of the circulator is used to output the target beam.

5. The device according to claim 4, characterized in that, The device also includes a first amplifier and a second amplifier; The second end of the beam splitter is connected to the first end of the first waveguide through the first amplifier. The first amplifier is used to adjust the optical power of the first scanning beam and to emit the first scanning beam with adjusted optical power into the first waveguide. The optical power of the first scanning beam with adjusted optical power is equal to or greater than the nonlinear effect power threshold. The third end of the beam splitter is connected to the first end of the frequency shifter through the second amplifier. The second amplifier is used to adjust the optical power of the second scanning beam and to transmit the second scanning beam with adjusted optical power to the frequency shifter.

6. The device according to claim 5, characterized in that, The device also includes a first filter and a second filter; The first amplifier is connected to the first end of the first waveguide through the first filter. The first filter is used to filter out noise from the first scanning beam and to transmit the first scanning beam after noise filtering into the first waveguide. The second amplifier is connected to the frequency shifter through the second filter, which is used to filter out noise from the second scanning beam and transmit the noise-filtered second scanning beam to the frequency shifter.

7. The device according to claim 6, characterized in that, The device also includes a first polarization controller and a second polarization controller; The first filter is connected to the first end of the first waveguide through the first polarization controller. The first polarization controller is used to adjust the polarization state of the first scanning beam to the target polarization state corresponding to the optical microcavity, and to emit the first scanning beam with adjusted polarization state into the first waveguide. The frequency shifter is connected to the second end of the circulator via the second polarization controller. The second polarization controller is used to adjust the polarization state of the third scanning beam to the target polarization state and to emit the polarization-adjusted third scanning beam into the circulator.

8. The device according to claim 4, characterized in that, The device also includes a detector and a controller; The detector is connected to the third end of the circulator, and the controller is connected to the laser, the frequency shifter, and the detector. The detector is used to detect the light beam output from the third end of the circulator; When the beam output from the third end of the circulator is the target beam, the controller controls the laser to stop the frequency change of the source scanning beam and controls the frequency shifter to stop the frequency change of the third scanning beam.

9. The device according to claim 8, characterized in that, After the beam output from the third end of the circulator becomes the target beam, when the optical power of the beam output from the third end of the circulator changes, the controller is also used to control the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the third end of the circulator recovers to the optical power of the target beam and then stops.

10. The device according to any one of claims 1-3, characterized in that, The device also includes a second waveguide and a third waveguide; The first end of the beam splitter is connected to the laser, the second end of the beam splitter is connected to the first end of the second waveguide, and the optical microcavity is coupled between the first end and the second end of the second waveguide; The third end of the beam splitter is connected to the first end of the frequency shifter, the second end of the frequency shifter is connected to the first end of the third waveguide, and the optical microcavity is coupled between the first and second ends of the third waveguide; The second waveguide is used to transmit the first scanning beam to the optical microcavity, the third waveguide is used to transmit the third scanning beam to the optical microcavity, and the second end of the second waveguide is used to output the target beam.

11. The device according to claim 10, characterized in that, The device also includes a first amplifier and a second amplifier; The second end of the beam splitter is connected to the first end of the second waveguide through the first amplifier. The first amplifier is used to adjust the optical power of the first scanning beam and to emit the first scanning beam with adjusted optical power into the second waveguide. The optical power of the first scanning beam with adjusted optical power is equal to or greater than the nonlinear effect power threshold. The third end of the beam splitter is connected to the first end of the frequency shifter through the second amplifier. The second amplifier is used to adjust the optical power of the second scanning beam and to transmit the second scanning beam with adjusted optical power to the frequency shifter.

12. The device according to claim 11, characterized in that, The device also includes a first filter and a second filter; The first amplifier is connected to the second waveguide through the first filter. The first filter is used to filter out noise from the first scanning beam and to transmit the first scanning beam after noise filtering to the second waveguide. The second amplifier is connected to the first end of the frequency shifter through the second filter. The second filter is used to filter out noise from the second scanning beam and to transmit the noise-filtered second scanning beam to the frequency shifter.

13. The device according to claim 12, characterized in that, The device also includes a first polarization controller and a second polarization controller; The first filter is connected to the first end of the second waveguide through the first polarization controller. The first polarization controller is used to adjust the polarization state of the first scanning beam to the target polarization state of the optical microcavity and to emit the polarization-adjusted first scanning beam into the second waveguide. The frequency shifter is connected to the first end of the third waveguide via the second polarization controller. The second polarization controller is used to adjust the polarization state of the third scanning beam to the target polarization state and to transmit the polarization-adjusted third scanning beam into the third waveguide.

14. The device according to claim 10, characterized in that, The device also includes a detector and a controller; The detector is connected to the second end of the second waveguide, and the controller is connected to the laser, the frequency shifter, and the detector. The detector is used to detect the light beam output from the second end of the third waveguide; When the beam output from the second end of the third waveguide is the target beam, the controller controls the laser to stop the frequency change of the source scanning beam and controls the frequency shifter to stop the frequency change of the third scanning beam.

15. The device according to claim 14, characterized in that, After the beam output from the second end of the third waveguide becomes the target beam, when the optical power of the beam output from the second end of the second waveguide changes, the controller is further configured to control the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the second end of the second waveguide recovers to the optical power of the target beam and then stops.

16. A method for generating an optical frequency comb, characterized in that, The method is applicable to an optical frequency comb generation device, the device including a laser, a beam splitter, a frequency shifter, and an optical microcavity, and the method includes: The laser generates a source scanning beam with a frequency varying in a first direction, and emits the source scanning beam toward the beam splitter; The source scanning beam is split into a first scanning beam and a second scanning beam by the beam splitter. The first scanning beam is emitted into the optical microcavity, and the second scanning beam is emitted into the frequency shifter. The optical power of the first scanning beam is equal to or greater than the nonlinear effect power threshold of the optical microcavity. The frequency shifter generates a third scanning beam with a frequency varying in a second direction based on the second scanning beam, and sends the third scanning beam to the optical microcavity; A target beam is generated by means of an optical microcavity when the first scanning beam is in the red detuning region of the optical microcavity and the third scanning beam is in the blue detuning region of the optical microcavity, wherein the spectrum of the target beam is a target optical frequency comb.

17. The method according to claim 16, characterized in that, The first scanning beam and the third scanning beam have opposite transmission directions in the optical microcavity.

18. The method according to claim 16 or 17, characterized in that, The frequency change rate of the third scanning beam is equal to or greater than the frequency change rate of the first scanning beam.

19. The method according to claim 16 or 17, characterized in that, The device also includes a first waveguide and a circulator; The step of emitting the first scanning beam into the optical microcavity includes: A first scanning beam is emitted through the optical microcavity guided by the first waveguide; Sending the third scanning beam to the optical microcavity includes: The third scanning beam is transmitted to the optical microcavity through the first waveguide and the circulator.

20. The method according to claim 19, characterized in that, The device also includes a detector and a controller; The method further includes: The detector detects the light beam output from the third end of the circulator; When it is determined that the beam output from the third end of the circulator is the target beam, the controller controls the laser to stop the frequency change of the source scanning beam and controls the frequency shifter to stop the frequency change of the third scanning beam.

21. The method according to claim 20, characterized in that, After determining that the beam output from the third end of the circulator is the target beam, the method further includes: When it is determined that the optical power of the beam output from the third end of the circulator has changed, the controller controls the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the third end of the circulator recovers to the optical power that hits the target beam.

22. The method according to claim 16 or 17, characterized in that, The device also includes a second waveguide and a third waveguide; The step of emitting the first scanning beam into the optical microcavity includes: The first scanning beam is emitted through the optical microcavity guided by the second waveguide; Sending the third scanning beam to the optical microcavity includes: The third scanning beam is emitted through the optical microcavity via the third waveguide.

23. The method according to claim 22, characterized in that, The device also includes a detector and a controller; The method further includes: The detector detects the light beam output from the second end of the second waveguide; When it is determined that the beam output from the second end of the second waveguide is the target beam, the controller controls the laser to stop the frequency change of the source scanning beam and controls the frequency shifter to stop the frequency change of the third scanning beam.

24. The method according to claim 23, characterized in that, After determining that the beam output from the second end of the second waveguide is the target beam, the method further includes: When it is determined that the optical power of the beam output from the second end of the second waveguide has changed, the controller controls the frequency shifter to change the frequency of the third scanning beam until the optical power of the beam output from the second end of the second waveguide recovers to the optical power of the target beam.

25. The method according to claim 19, characterized in that, The device also includes a first amplifier and a second amplifier; The method further includes: The optical power of the first scanning beam is adjusted by the first amplifier, wherein the optical power of the first scanning beam after the optical power adjustment is equal to or greater than the nonlinear effect power threshold. The optical power of the second scanning beam is adjusted by the second amplifier.

26. The method according to claim 25, characterized in that, The device also includes a first filter and a second filter; The method further includes: The first filter is used to filter out noise from the first scanning beam after the optical power is adjusted. The second filter removes noise from the second scanning beam after the optical power has been adjusted.

27. The method according to claim 26, characterized in that, The device also includes a first polarization controller and a second polarization controller; The method further includes: The polarization state of the noise-filtered first scanning beam is adjusted to the target polarization state of the optical microcavity by the first polarization controller. The polarization state of the third scanning beam is adjusted to the target polarization state by the second polarization controller.

28. A light emitting device, characterized in that, The optical emitting device includes an optical frequency comb generating device and an optical signal processor as described in any one of claims 1-15; The optical frequency comb generating device is used to generate a target beam, wherein the spectrum of the target beam is a target optical frequency comb; The optical signal processor is used to modulate the target beam and output the target signal light.

29. An optical communication system, characterized in that, The optical communication system includes the optical transmitting device and the optical receiving device as described in claim 28; The optical emitting device is used to generate and transmit the target signal light to the optical receiving device.

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