Device and method for generating high-coherence parallel light source

Abstract

The invention provides a device and a method for generating a high-coherence parallel light source, and relates to the field of lasers. The device comprises a narrow linewidth optical frequency comb generation unit which comprises a first distributed feedback laser and a micro-ring resonant cavity, output light of the first distributed feedback laser is coupled into the micro-ring resonant cavity, and narrow linewidth laser is generated through a self-injection locking mechanism; the narrow linewidth laser is converted into an optical frequency comb with a plurality of comb teeth by using the nonlinear effect of the micro-ring resonant cavity; the wavelength division demultiplexing unit is used for performing wavelength separation on the plurality of comb teeth of the optical frequency comb to form a plurality of single-wavelength optical comb teeth; and the low-noise high-gain amplification unit is used for injecting and locking the comb teeth of the optical comb of each single wavelength into the second distributed feedback laser to generate a high-coherence parallel light source. According to the multi-wavelength light source, the application requirement of future integrated photonics in a large-scale high-parallel coherent system can be met, and the multi-wavelength light source which is high in coherence, high in power, high in conversion efficiency, flat and easy to integrate is generated.

Description

Technical Field

[0001] This disclosure relates to the field of lasers, and more particularly to an apparatus and method for generating a highly coherent parallel light source. Background Technology

[0002] Coherent optics has profoundly impacted applications such as optical communication, lidar, optical computing, quantum computing, optical sensing, and imaging. For example, in optical communication, coherent detection offers better noise suppression and interference resistance, lower bit error rates, and can increase data transmission rates through higher-order modulation formats. In lidar, coherent technology enables faster and more accurate measurement of object distance and velocity. Furthermore, coherent technology ensures high fidelity in quantum mechanics, generates large-scale entanglement, and improves the accuracy and parallelism of quantum computing.

[0003] Currently, a major trend in integrated photonics is the adoption of coherent techniques to meet the increasing demands for capacity and precision. However, developing coherent systems in integrated optics requires significant investment in hardware integration and energy efficiency. Particularly in the area of ​​light sources, no method has yet been able to simultaneously achieve a balance between high parallelism, high coherence, and high power.

[0004] The most commonly used on-chip light source—the III-V group first distributed feedback laser (DFB1)—performs excellently in terms of power and electro-optical conversion efficiency, but its inherent linewidth is typically around 100 kHz, making it difficult to meet the coherence requirements of many applications. To improve coherence, the III-V laser is often coupled to a resonant cavity with a high quality factor (Q value), which can effectively reduce the linewidth to the sub-kilohertz level, but at the expense of power and electro-optical conversion efficiency. High-Q resonators are also used to generate optical frequency combs to produce parallel light sources, but the nonlinear frequency conversion process typically has only a light-to-light conversion efficiency of a few hundredths, further limiting the channel power. For integrated microcavity optical frequency combs, existing solutions suffer from low comb power and low wall insertion efficiency, making them unsuitable for direct use as a light source in coherent optical systems. Furthermore, the amplification of the optical comb power by erbium-doped fiber amplifiers and semiconductor optical amplifiers introduces additional noise, significantly degrading the performance of coherent optical systems. Summary of the Invention

[0005] In view of the above problems, this disclosure provides an apparatus and method for generating a highly coherent parallel light source, which realizes a highly coherent parallel light source in an advanced integrated coherent system at the lowest cost.

[0006] One aspect of this disclosure provides a device for generating a highly coherent parallel light source, comprising: a narrow-linewidth optical frequency comb generation unit, including a first distributed feedback laser and a microring resonator, wherein the output light of the first distributed feedback laser is coupled into the microring resonator and a narrow-linewidth laser is generated through a self-injection locking mechanism; the narrow-linewidth laser is converted into an optical frequency comb with multiple comb teeth by utilizing the nonlinear effect of the microring resonator; a wavelength decomposition and multiplexing unit is used to perform wavelength separation on the multiple comb teeth of the optical frequency comb to form multiple single-wavelength optical comb teeth; and a low-noise, high-gain amplification unit is used to inject and lock each single-wavelength optical comb tooth into a second distributed feedback laser to generate a highly coherent parallel light source.

[0007] According to embodiments of this disclosure, a first distributed feedback laser and a microring resonator are integrated or coupled together.

[0008] According to embodiments of this disclosure, the wave demultiplexing unit includes a thin-film filter, an arrayed waveguide grating, and a fiber Bragg grating.

[0009] According to embodiments of this disclosure, the low-noise high-gain amplification unit further includes a circulator for injecting each single-wavelength optical comb tooth into the front cavity surface of the second distributed feedback laser; the low-noise high-gain amplification unit also injects each single-wavelength optical comb tooth into the rear cavity surface of the second distributed feedback laser.

[0010] According to embodiments of this disclosure, the generating apparatus further includes a wavelength division multiplexer for combining multiple optical comb teeth of different wavelengths after injection locking to form a highly coherent parallel light source.

[0011] Another aspect of this disclosure provides a method for generating a highly coherent parallel light source, comprising: step S1, coupling the output light of a first distributed feedback laser into a microring resonator through a self-injection locking mechanism to generate a narrow linewidth laser; utilizing the nonlinear effect of the microring resonator to convert the narrow linewidth laser into an optical frequency comb with multiple comb teeth; step S2, performing wavelength separation on each comb tooth of the optical frequency comb to form multiple single-wavelength optical comb teeth; step S3, injecting and locking each single-wavelength optical comb tooth into a second distributed feedback laser and combining the beams to generate a highly coherent parallel light source.

[0012] According to an embodiment of this disclosure, in step S1, the generation of the optical frequency comb and the narrowing of the linewidth are achieved by any of the following methods: adjusting the driving current of the first distributed feedback laser; adjusting the spacing between the first distributed feedback laser and the microring resonator when the first distributed feedback laser and the microring resonator are coupled; and tuning the phase on the bus waveguide when the first distributed feedback laser and the microring resonator are integrated through a bus waveguide.

[0013] According to an embodiment of this disclosure, in step S1, both the first distributed feedback laser and the microring resonator are placed on a temperature control console.

[0014] According to an embodiment of this disclosure, step S3 includes: injecting each single-wavelength optical comb tooth into the front cavity surface of the second distributed feedback laser through a circulator; or injecting each single-wavelength optical comb tooth into the rear cavity surface of the second distributed feedback laser.

[0015] According to an embodiment of this disclosure, step S3 further includes: using a wavelength division multiplexer to combine multiple optical comb teeth of different wavelengths after injection locking to form a highly coherent parallel light source.

[0016] Compared with the prior art, the apparatus and method for generating a highly coherent parallel light source provided in this disclosure have at least the following advantages:

[0017] (1) This device can meet the application requirements of future integrated photonics in large-scale high parallel coherent systems, and generate a multi-wavelength light source with high coherence, high power, high conversion efficiency, flatness and easy integration.

[0018] (2) This method possesses advantages such as high gain, narrow linewidth, and high electro-optic conversion efficiency, enabling the realization of highly coherent parallel light sources in advanced integrated coherent systems at the lowest cost. This method can achieve highly coherent, low-noise parallel light sources with linewidths as low as 10 Hz and power exceeding 20 dBm, achieving an overall electro-optic efficiency of 19%, comparable to advanced semiconductor lasers. The resulting highly coherent parallel light source paves the way for scalable, high-performance coherent integrated photonic systems, potentially benefiting a wider range of applications. Attached Figure Description

[0019] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0020] Figure 1 The diagram schematically illustrates a structural diagram of a high-coherence parallel light source generation apparatus according to an embodiment of the present disclosure;

[0021] Figure 2 A schematic diagram of the generation unit of a narrow linewidth optical frequency comb according to an embodiment of the present disclosure is shown.

[0022] Figure 3 A schematic diagram of a low-noise, high-gain amplifier unit according to an embodiment of the present disclosure is shown.

[0023] Figure 4 A flowchart illustrating a method for generating a highly coherent parallel light source according to an embodiment of the present disclosure is shown schematically.

[0024] Figure 5The illustration shows the effect of the self-injection locking mechanism according to an embodiment of the present disclosure;

[0025] Figure 6 The spectrum of an optical frequency comb according to an embodiment of the present disclosure is schematically shown.

[0026] Figure 7 A schematic diagram illustrating the result of single-wavelength injection locking according to an embodiment of the present disclosure;

[0027] Figure 8 The diagram schematically illustrates the result of a highly coherent parallel light source according to an embodiment of the present disclosure.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1-Narrow linewidth optical frequency comb generation unit; DFB1-First distributed feedback laser; MRR-Microring resonator;

[0030] DEMUX - Wavelet decomposition and multiplexing unit;

[0031] 2-Low-noise, high-gain amplifier unit; Circ-Circulator; Iso-Isolator; DFB2-Second distributed feedback laser;

[0032] MUX - Wavelength Division Multiplexer. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0034] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0035] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0036] When using expressions such as "at least one of A, B, and C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C. Similarly, when using expressions such as "at least one of A, B, or C," the meaning should generally be interpreted according to the understanding of someone skilled in the art. For example, "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C.

[0037] Example 1

[0038] This embodiment provides a device for generating a highly coherent parallel light source, such as... Figures 1 to 3 As shown, the system includes a narrow linewidth optical frequency comb generation unit 1, a wave decomposition and multiplexing unit DEMUX, and a low-noise high-gain amplification unit 2. The narrow linewidth optical frequency comb generation unit 1 includes a first distributed feedback laser DFB1 and a microring resonator MRR, while the low-noise high-gain amplification unit 2 includes a second distributed feedback laser DFB2.

[0039] The output light of the first distributed feedback laser DFB1 is coupled into the micro-ring resonator MRR, and a narrow linewidth laser is generated through the self-injection locking mechanism. The narrow linewidth laser is converted into an optical frequency comb with multiple comb teeth by utilizing the nonlinear effect of the micro-ring resonator MRR.

[0040] The wavelength demultiplexing unit (DEMUX) is used to separate the wavelengths of multiple teeth of an optical frequency comb, forming multiple single-wavelength optical comb teeth.

[0041] The low-noise, high-gain amplification unit 2 is used to inject each single-wavelength optical comb tooth into the locked second distributed feedback laser DFB2 to generate a highly coherent parallel light source.

[0042] Through the embodiments of this disclosure, a high-coherence parallel light source is generated based on self-injection locking and injection locking, thereby achieving high-power, high-coherence parallel light source output.

[0043] In the generation unit 1 of the narrow linewidth optical frequency comb, the first distributed feedback laser DFB1 and the microring resonator MRR are integrated or coupled together. The microring resonator MRR is made of a high quality factor (Q-value) material, for example, with a quality factor of 1×10⁻⁶. 6 The materials used can be nonlinear materials such as silicon nitride and aluminum gallium arsenide (AlGaAs).

[0044] Thus, through a self-injection locking mechanism, the light from the first distributed feedback laser DFB1 is coupled to the microring resonator, thereby generating narrow-linewidth laser light. Then, the nonlinear effect of the microring resonator is used to generate an optical frequency comb.

[0045] In this embodiment, the wavelength demultiplexing unit (DEMUX) includes a thin-film filter, an arrayed waveguide grating, and a fiber Bragg grating. The DEMUX separates the wavelengths of each tooth of the optical frequency comb.

[0046] In this embodiment, the low-noise high-gain amplification unit 2 further includes a circulator Circ, which is used to inject each single-wavelength optical comb tooth into the front cavity surface (light-emitting surface) of the second distributed feedback laser DFB2.

[0047] The low-noise, high-gain amplifier unit 2 also injects each single-wavelength optical comb tooth into the back cavity surface of the second distributed feedback laser DFB2.

[0048] For example, each single-wavelength optical comb tooth can be injected into the back cavity surface of the second distributed feedback laser DFB2 using an isolator. Alternatively, each single-wavelength optical comb tooth can be directly injected into the back cavity surface of the second distributed feedback laser DFB2.

[0049] For example in Figure 1 In this context, 'a' and 'b1' differ only in the low-noise, high-gain amplifier unit 2. 'a' indicates injection locking using a circulator (Circ); 'b1' indicates direct injection locking. And... Figure 3 In the diagram, 'a' indicates that injection locking is performed using the circulator Circ; 'b2' indicates that injection locking is performed using the isolator Iso.

[0050] Understandably, the front cavity surface of the second distributed feedback laser DFB2 serves as the light-emitting surface or output end, while the rear cavity surface acts as the reflecting surface. The laser emitted from the front cavity surface serves as a highly coherent, high-power, and low-noise light source.

[0051] As can be seen, the low-noise high-gain amplification unit 2 uses an optical frequency comb as a seed light source, injects and locks each comb tooth, drives the second distributed feedback laser DFB2, realizes the power amplification of each comb tooth, and thus obtains a highly coherent parallel light source.

[0052] In this embodiment, there can be multiple second distributed feedback lasers DFB2, the number of which is the same as the number of teeth on multiple single-wavelength optical combs. These multiple second distributed feedback lasers DFB2 can be independent of each other or can be an integrated laser array.

[0053] It should be understood that the first distributed feedback laser DFB1 and the second distributed feedback laser DFB2 in this embodiment are only for easy distinction. Both are distributed feedback lasers, but they can have the same laser parameters or different laser parameters. The specific parameters are not limited in this disclosure.

[0054] In this embodiment, the device for generating the highly coherent parallel light source further includes: as follows: Figure 1 The wavelength division multiplexer (MUX) shown is used to combine multiple optical comb teeth of different wavelengths after injection locking to form a highly coherent parallel light source.

[0055] Through the above embodiments, this disclosure provides a device for generating a highly coherent parallel light source, which can meet the application requirements of integrated photonics in large-scale highly parallel coherent systems in the future, and generate a multi-wavelength light source with high coherence, high power, high conversion efficiency, flatness and easy integration.

[0056] Example 2

[0057] This embodiment provides a method for generating a highly coherent parallel light source, implemented using the highly coherent parallel light source generation apparatus described in Embodiment 1. The method is as follows: Figure 4 As shown, it includes steps S1 to S3.

[0058] Step S1: The output light of the first distributed feedback laser is coupled into the micro-ring resonator through a self-injection locking mechanism to generate a narrow linewidth laser; the narrow linewidth laser is converted into an optical frequency comb with multiple comb teeth by utilizing the nonlinear effect of the micro-ring resonator.

[0059] Step S2 involves wavelength separation of each tooth of the optical frequency comb to form multiple single-wavelength optical comb teeth.

[0060] Step S3: Inject each single-wavelength optical comb tooth into the locked second distributed feedback laser and combine the beams to generate a highly coherent parallel light source.

[0061] In this design, a first distributed feedback laser without an isolator is integrated with a microring resonator via integration or direct coupling. This approach allows the output light from the first distributed feedback laser to enter the microring resonator when its wavelength is within the locked bandwidth range. The light then undergoes Rayleigh reflection within the ring, resulting in narrowband filtering and reflection. This reflected light re-enters the first distributed feedback laser, forcing it to oscillate at its resonant peak frequency, thus suppressing frequency noise in the output light. Furthermore, because the wavelength of the first distributed feedback laser is drawn to the resonant frequency of the microring resonator, the cavity power increases, the Kerr nonlinearity evolves towards the operating point, and the power exceeds the parametric oscillation threshold. The presence of intracavity reflection causes coupling between forward and reverse propagation modes, resulting in mode splitting and local anomalous dispersion. Therefore, when the cavity reaches steady state, a mode-locked dark pulse frequency comb can be generated, with each comb tooth inheriting the narrowed linewidth of the self-injected locked pump source.

[0062] In this embodiment, in step S1, the generation of the optical frequency comb and the narrowing of the linewidth are achieved by any of the following methods: adjusting the driving current of the first distributed feedback laser; adjusting the spacing between the first distributed feedback laser and the microring resonator when the first distributed feedback laser and the microring resonator are coupled; and tuning the phase on the bus waveguide when the first distributed feedback laser and the microring resonator are integrated through a bus waveguide.

[0063] In this embodiment, in step S1, both the first distributed feedback laser and the micro-ring resonator are placed on a temperature control console.

[0064] In this embodiment, step S3 includes: injecting each single-wavelength optical comb tooth into the front cavity surface of the second distributed feedback laser through a circulator; or, injecting each single-wavelength optical comb tooth into the rear cavity surface of the second distributed feedback laser.

[0065] In this embodiment, step S3 further includes: using a wavelength division multiplexer to combine multiple optical comb teeth of different wavelengths after injection locking to form a highly coherent parallel light source.

[0066] Specifically, to stably and smoothly achieve the generation of the optical frequency comb and the narrowing of the linewidth, depending on the connection method between the first distributed feedback laser and the microring resonator (e.g., integrated or directly coupled), the spacing between the first distributed feedback laser and the microring resonator, or the phase on the tuned bus waveguide, can be adjusted to achieve precise control of the reflected light phase. Simultaneously, both the first distributed feedback laser and the microring resonator can be placed on a temperature control console to ensure that both are in a stable environmental state.

[0067] After setting the appropriate working conditions, the self-injection locked optical frequency comb can be quickly generated by simply turning on the driving current of the first distributed feedback laser without any auxiliary means. The generated optical frequency comb can be called a turnkey optical frequency comb.

[0068] For example, by setting the drive current of the first distributed feedback laser to a frequency-sweeping triangular wave signal, the output wavelength of the first distributed feedback laser can be scanned, and the scanning wavelength range can cover the resonant peak of the microcavity. After optical coupling into the microring resonator, the transmitted light is collected by a photodetector at its output end and displayed in real time on an oscilloscope. By adjusting the drive current, adjusting the distance between the first distributed feedback laser and the microring resonator, or tuning the phase on the bus waveguide, the phase of the reflected light can be controlled. When adjusted to a suitable position, a vertically steep drop in the transmitted light power can be observed on the oscilloscope; this is a characteristic of self-injection locking. Figure 5 As shown. In Figure 5 In the diagram, the horizontal axis represents time, the left vertical axis represents the normalized transmission spectrum, and the right vertical axis represents the scan current. Analysis shows that within the self-injection locked bandwidth, the wavelength of the first distributed feedback laser is pulled to the resonant peak wavelength, resulting in more light entering the micro-ring resonator and thus reducing the transmitted light power.

[0069] Next, by fixing the driving current at the position of this steep drop edge, a narrow linewidth optical frequency comb can be obtained, with a spectrum as shown in the figure. Figure 6 As shown. In Figure 6 In the diagram, the horizontal axis represents wavelength, and the vertical axis represents output power.

[0070] Then, the optical frequency comb is divided into multiple single-wavelength optical comb teeth by a wave demultiplexing unit. The wave demultiplexing unit can be a thin-film filter, an arrayed waveguide grating, a fiber Bragg grating, etc.

[0071] Based on this, each single-wavelength optical comb tooth is used as the main laser, and the light is injected through the output end of the second distributed feedback laser via a circulator, or the light is injected into the reflective surface of the second distributed feedback laser after passing through an isolator.

[0072] When the wavelength of the injected light is sufficiently close to the wavelength at which the second distributed feedback laser operates freely, the second distributed feedback laser will be forced to synchronize with the injected light, following the frequency of the injected light with a relatively constant output optical power. For example... Figure 7As shown in the left figure, the horizontal axis represents wavelength and the vertical axis represents output power. It can be seen that the output power of the single-wavelength injection lock is approximately 20 dBm, the same as the output power of the second distributed feedback laser, and the power amplification can reach over 60 dB. Simultaneously, this disclosure also uses a time-delayed self-heterodyne beat frequency method to measure noise, such as... Figure 7 As shown in the right figure, the horizontal axis represents the offset frequency, and the vertical axis represents the frequency noise power spectral density. It can be seen that the noise of the laser after injection-locked amplification does not increase significantly and is completely independent of the noise of the second distributed feedback laser during free operation. This demonstrates that the proposed method can maintain the low-noise light source characteristics of a narrow-linewidth master laser.

[0073] Finally, by combining the light of each wavelength, we can obtain, as shown below. Figure 8 As shown, this is a multi-wavelength light source with high coherence, high power, high conversion efficiency, flatness, and easy integration. Figure 8 In the diagram, the horizontal axis represents wavelength, and the vertical axis represents output power.

[0074] Through the above embodiments, this disclosure provides a method for generating a highly coherent parallel light source, which possesses advantages such as high gain, narrow linewidth, and high electro-optic conversion efficiency, enabling the realization of a highly coherent parallel light source in advanced integrated coherent systems at the lowest cost. This method can achieve highly coherent, low-noise parallel light sources with linewidths as low as 10 Hz and power exceeding 20 dBm, achieving an overall electro-optic efficiency of 19%, comparable to advanced semiconductor lasers. The generated highly coherent parallel light source paves the way for realizing scalable, high-performance coherent integrated photonic systems, and is expected to benefit a wider range of applications.

[0075] It should be noted that the embodiments of the device part are similar to those of the method part, and the technical effects achieved are also similar.

[0076] It should also be noted that directional terms mentioned in the embodiments, such as "front" and "back," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of this disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding this disclosure.

[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. Furthermore, the word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0078] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A device for generating a highly coherent parallel light source, characterized in that, include: The narrow linewidth optical frequency comb generation unit (1) includes a first distributed feedback laser (DFB1) and a microring resonator (MRR). The output light of the first distributed feedback laser (DFB1) is coupled into the microring resonator (MRR) to generate a narrow linewidth laser through a self-injection locking mechanism. The narrow linewidth laser is converted into an optical frequency comb with multiple comb teeth by utilizing the nonlinear effect of the microring resonator (MRR). Wavelength demultiplexing unit (DEMUX) is used to separate the wavelengths of multiple teeth of the optical frequency comb to form multiple single-wavelength optical comb teeth; A low-noise, high-gain amplification unit (2) is used to inject each of the single-wavelength optical comb teeth into a locked second distributed feedback laser (DFB2) to generate a highly coherent parallel light source.

2. The generating apparatus according to claim 1, characterized in that, The first distributed feedback laser (DFB1) and the microring resonator (MRR) are integrated or coupled together.

3. The generating apparatus according to claim 1, characterized in that, The Wavelet Decomposition and Multiplexing Unit (DEMUX) includes a thin-film filter, an arrayed waveguide grating, and a fiber Bragg grating.

4. The generating apparatus according to claim 1, characterized in that, The low-noise high-gain amplification unit (2) also includes a circulator for injecting each of the single-wavelength optical comb teeth into the front cavity surface of the second distributed feedback laser (DFB2); The low-noise, high-gain amplification unit (2) also injects each of the single-wavelength optical comb teeth into the back cavity surface of the second distributed feedback laser (DFB2).

5. The generating apparatus according to claim 1, characterized in that, The generating device further includes: A wavelength division multiplexer (MUX) is used to combine multiple optical comb teeth of different wavelengths after injection locking to form a highly coherent parallel light source.

6. A method for generating a highly coherent parallel light source, characterized in that, include: Step S1: Through a self-injection locking mechanism, the output light of the first distributed feedback laser is coupled into the micro-ring resonator to generate a narrow linewidth laser. The narrow-linewidth laser is converted into an optical frequency comb with multiple teeth by utilizing the nonlinear effect of the micro-ring resonator. Step S2: Wavelength separation is performed on each tooth of the optical frequency comb to form multiple single-wavelength optical comb teeth; Step S3: Inject each of the single-wavelength optical comb teeth into the locked second distributed feedback laser and combine the beams to generate a highly coherent parallel light source.

7. The method of production according to claim 6, characterized in that, In step S1, the optical frequency comb is generated and the linewidth is narrowed using any of the following methods: Adjust the driving current of the first distributed feedback laser; When the first distributed feedback laser and the microring resonator are coupled, the distance between the first distributed feedback laser and the microring resonator is adjusted. When the first distributed feedback laser and the microring resonator are integrated through a bus waveguide, the phase on the bus waveguide is tuned.

8. The method of production according to claim 6, characterized in that, In step S1, both the first distributed feedback laser and the micro-ring resonator are placed on a temperature control console.

9. The method of production according to claim 6, characterized in that, Step S3 includes: Each single-wavelength optical comb tooth is injected into the front cavity surface of the second distributed feedback laser via a circulator; or Each of the single-wavelength optical comb teeth is injected into the back cavity surface of the second distributed feedback laser.

10. The method of production according to claim 6, characterized in that, Step S3 further includes: A wavelength division multiplexer is used to combine multiple optical combs of different wavelengths after injection locking to form a highly coherent parallel light source.

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