Wavelength calibration device and method for injection type locking optical comb

Abstract

The invention relates to the technical field of optical comb wavelength calibration, in particular to a wavelength calibration device and method of an injection type locking optical comb, which can be used for optical comb wavelength calibration of an injection type locking method. According to the femtosecond laser frequency comb, injection type locking is adopted, complex optical and electrical locking needed by a traditional femtosecond laser frequency comb is avoided, and the system structure is greatly simplified. The cost of the system is reduced, and the reliability and the stability of the system are improved. The beat frequency process is realized by using the narrow linewidth laser and the photoelectric detector, and the wavelength change of the mid-infrared light frequency comb can be monitored in real time.

Description

Technical Field

[0001] The present invention relates to the technical field of optical comb wavelength calibration, and in particular to a wavelength calibration device and method for an injection-locked optical comb. Background Art

[0002] Traditional femtosecond laser frequency combs use repetition frequency locking and carrier-envelope phase shift frequency locking to achieve wavelength locking. However, the carrier-envelope phase shift frequency locking method uses complex optical and electrical locking methods, which makes the system relatively large, limiting its development in various fields. The injection-locked optical comb uses the injection locking method of optical parametric amplification to achieve laser wavelength locking. The system is relatively simple, so it is suitable for spectral temperature measurement and other directions.

[0003] However, the wavelengths of the injection-locked optical combs currently used are all in the mid-infrared band. The wavelength meters and spectrometers in this band are relatively large, which limits their application in application scenarios that require real-time monitoring of laser wavelengths. Summary of the invention

[0004] In view of this, the present invention provides a wavelength calibration device and method for an injection-locked optical comb, which can be used for wavelength calibration of an optical comb in an injection-locked method.

[0005] To achieve the above purpose, the technical solution of the present invention is as follows:

[0006] A wavelength calibration device for an injection-locked optical comb, comprising an injection-locked mid-infrared optical frequency comb, a semi-transparent and semi-reflective mirror, a photodetector, and a narrow linewidth laser;

[0007] Among them, the injection-locked mid-infrared frequency comb outputs a mid-infrared frequency comb laser, and the narrow-linewidth laser outputs a narrow-linewidth laser; the mid-infrared frequency comb laser transmitted through a semi-transparent and semi-reflective mirror and the narrow-linewidth laser reflected through a semi-transparent and semi-reflective mirror are combined and input into a photodetector together, and a beat frequency process is realized on the photodetector. The beat frequency results are processed by a computer to obtain the wavelength information of the measured laser.

[0008] The injection-locked mid-infrared optical frequency comb includes a pump laser, a frequency conversion crystal and a reference laser; the pump laser and the reference laser are simultaneously input into the frequency conversion crystal to achieve injection locking of the mid-infrared optical frequency comb.

[0009] The phase of the mid-infrared optical frequency comb is kept consistent with that of the reference laser.

[0010] Among them, the laser wavelength is 4.176um.

[0011] The present invention also proposes a wavelength calibration method for an injection-locked optical comb, which is implemented using the device of the present invention and includes the following steps:

[0012] Step 1, achieving injection locking of the mid-infrared optical frequency comb;

[0013] Step 2, controlling the injection-locked mid-infrared frequency comb to output a mid-infrared frequency comb laser, and controlling the narrow-linewidth laser to output a narrow-linewidth laser;

[0014] Step 3, adjusting the semi-transparent and semi-reflective mirror so that the mid-infrared optical frequency comb laser transmitted by the semi-transparent and semi-reflective mirror and the narrow line width laser reflected by the semi-transparent and semi-reflective mirror are combined and input to the photodetector together to realize the beat frequency process on the photodetector;

[0015] Step 4: Process the beat frequency result by computer to obtain the wavelength information of the measured laser.

[0016] Among them, the injection-locked mid-infrared optical frequency comb includes a pump laser, a frequency conversion crystal and a reference laser; the injection-locking process of the mid-infrared optical frequency comb is as follows:

[0017] The pump laser and the reference laser are simultaneously input into the frequency conversion crystal to achieve injection locking of the mid-infrared optical frequency comb.

[0018] Among them, the phase of the mid-infrared optical frequency comb is kept consistent with that of the reference laser.

[0019] Among them, the laser wavelength is 4.176um.

[0020] Beneficial effects:

[0021] 1. The device of the present invention adopts injection locking, avoiding the complex optical and electrical locking required by the traditional femtosecond laser frequency comb, and greatly simplifying the system structure. This not only reduces the cost of the system, but also improves the reliability and stability of the system; by using narrow linewidth lasers and photodetectors to realize the beat frequency process, the present invention can monitor the wavelength changes of the mid-infrared optical frequency comb in real time. This is of great significance for application scenarios that require real-time wavelength calibration (such as spectral temperature measurement, gas detection, etc.).

[0022] 2. The device of the present invention adopts injection locking combined with the use of narrow linewidth lasers to achieve high-precision wavelength calibration. The stability and high-precision characteristics of narrow linewidth lasers ensure the accuracy of wavelength measurement and improve the performance of the overall system.

[0023] 3. Compared with the traditional complex system, the device of the present invention is smaller in size, lighter in weight, and easier to carry and move. This allows the device to be used in more occasions, especially in field operations and field tests. At the same time, the simplified system structure reduces the number of failure points, reduces the difficulty and cost of maintenance. At the same time, the stability and reliability of the system are also improved, extending the service life.

[0024] 4. The real-time wavelength calibration function of the present invention enables researchers to quickly obtain accurate wavelength data, improving experimental efficiency. This has important practical value for experimental research that requires frequent adjustment and calibration of wavelengths. It provides researchers with an efficient and accurate tool that helps promote scientific research and technological progress in related fields. Especially in the research of the mid-infrared band, it can provide strong support for the development of new materials and new devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the device of the present invention. DETAILED DESCRIPTION

[0026] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0027] The present invention provides a wavelength calibration device for an injection-locked optical comb, such as Figure 1 As shown, it includes an injection-locked mid-infrared optical frequency comb, a semi-transparent and semi-reflective mirror, a photodetector, and a narrow-linewidth laser.

[0028] The injection-locked mid-infrared frequency comb outputs a mid-infrared frequency comb laser, and the narrow linewidth laser outputs a narrow linewidth laser; the mid-infrared frequency comb laser transmitted by the semi-transparent and semi-reflective mirrors and the narrow linewidth laser reflected by the semi-transparent and semi-reflective mirrors are combined and input to the photodetector together, and the beat frequency process is realized on the photodetector. The beat frequency results are processed by a computer to obtain the wavelength information of the measured laser. The mid-infrared frequency comb laser passes through the above optical path to realize the measurement of the injection-locked mid-infrared frequency comb wavelength by the narrow linewidth laser.

[0029] Specifically, the injection-locked mid-infrared optical frequency comb includes a pump laser, a frequency conversion crystal and a reference laser; the pump laser and the reference laser are simultaneously input into the frequency conversion crystal to achieve injection locking of the mid-infrared optical frequency comb, and the phase of the mid-infrared optical frequency comb is kept consistent with the reference laser.

[0030] In this embodiment, the laser wavelength is 4.176 um, the wavelength is monitored in real time, and a narrow linewidth laser is used to implement wavelength phase calibration of an injection-locked femtosecond optical frequency comb.

[0031] The device of the present invention can be widely used in the debugging and testing process of mid-infrared lasers to achieve the purpose of real-time calibration. It is oriented to the laboratories of scientific research institutes and has extremely high application value and promotion value. The present invention is not only suitable for wavelength calibration of optical frequency combs in the mid-infrared band, but can also be extended to the application of optical frequency combs in other bands. In particular, it has broad application prospects in fields that require high-precision wavelength measurement and real-time monitoring, such as scientific research, industrial production, and medical diagnosis.

[0032] The present invention also provides a wavelength calibration method for an injection-locked optical comb, which is implemented based on the device of the present invention and includes the following steps:

[0033] Step 1, achieving injection locking of the mid-infrared optical frequency comb;

[0034] Step 2, controlling the injection-locked mid-infrared frequency comb to output a mid-infrared frequency comb laser, and controlling the narrow-linewidth laser to output a narrow-linewidth laser;

[0035] Step 3, adjusting the semi-transparent and semi-reflective mirror so that the mid-infrared optical frequency comb laser transmitted by the semi-transparent and semi-reflective mirror and the narrow line width laser reflected by the semi-transparent and semi-reflective mirror are combined and input to the photodetector together to realize the beat frequency process on the photodetector;

[0036] Step 4: Process the beat frequency result by computer to obtain the wavelength information of the measured laser.

[0037] Furthermore, in the method of the present invention, the injection-locked mid-infrared optical frequency comb includes a pump laser, a frequency conversion crystal, and a reference laser; the injection-locking process of the mid-infrared optical frequency comb is:

[0038] The pump laser and the reference laser are simultaneously input into the frequency conversion crystal to achieve injection locking of the mid-infrared optical frequency comb, and the phase of the mid-infrared optical frequency comb remains consistent with that of the reference laser.

[0039] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wavelength calibration device for an injection-locked optical comb, characterized in that: Including injection-locked mid-infrared optical frequency comb, semi-transparent and semi-reflective mirrors, photodetectors and narrow linewidth lasers; Among them, the injection-locked mid-infrared frequency comb outputs a mid-infrared frequency comb laser, and the narrow-linewidth laser outputs a narrow-linewidth laser; the mid-infrared frequency comb laser transmitted through a semi-transparent and semi-reflective mirror and the narrow-linewidth laser reflected through a semi-transparent and semi-reflective mirror are combined and input into a photodetector together, and a beat frequency process is realized on the photodetector. The beat frequency results are processed by a computer to obtain the wavelength information of the measured laser.

2. The device according to claim 1, characterized in that The injection-locked mid-infrared optical frequency comb comprises a pump laser, a frequency conversion crystal and a reference laser; the pump laser and the reference laser are simultaneously input into the frequency conversion crystal to achieve injection locking of the mid-infrared optical frequency comb.

3. The device according to claim 2, characterized in that ,The phase of the mid-infrared frequency comb is kept consistent with the reference laser.

4. The device according to any one of claims 1 to 3, characterized in that , the laser wavelength is 4.176um.

5. A wavelength calibration method for an injection-locked optical comb, characterized in that , implemented by the device as described in any one of claims 1 to 4, comprising the following steps: Step 1, achieving injection locking of the mid-infrared optical frequency comb; Step 2, controlling the injection-locked mid-infrared frequency comb to output a mid-infrared frequency comb laser, and controlling the narrow-linewidth laser to output a narrow-linewidth laser; Step 3, adjusting the semi-transparent and semi-reflective mirror so that the mid-infrared optical frequency comb laser transmitted by the semi-transparent and semi-reflective mirror and the narrow line width laser reflected by the semi-transparent and semi-reflective mirror are combined and input to the photodetector together to realize the beat frequency process on the photodetector; Step 4: Process the beat frequency result by computer to obtain the wavelength information of the measured laser.

6. The method according to claim 5, characterized in that ,Injection-locked mid-infrared optical frequency comb includes pump laser, frequency conversion crystal and reference laser; the injection-locking process of mid-infrared optical frequency comb is: The pump laser and the reference laser are simultaneously input into the frequency conversion crystal to achieve injection locking of the mid-infrared optical frequency comb.

7. The method according to claim 6, characterized in that ,The phase of the mid-infrared frequency comb is kept consistent with the reference laser.

8. The method according to any one of claims 5 to 7, characterized in that , the laser wavelength is 4.176um.

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