A tunable dual-wavelength laser output device

Abstract

The present invention discloses a tunable dual-wavelength laser output device, belonging to the field of semiconductor laser technology. The tunable dual-wavelength laser output device includes: a beam fast-axis collimation system that converts the beam emitted by a single blue laser tube into collimated light; a dual-wavelength spectroscopic beamwidth compression system comprising two beam reflectors, two beam expansion subsystems, a transmission grating, and two plane reflectors; the beam reflectors intercept a portion of the collimated light that enters the beam expansion subsystem, while the remaining collimated light enters the laser output characteristic measurement system; the transmission grating diffracts the expanded beam and outputs it to the plane reflector; the plane reflector reflects the vertically incident laser light, returning it along the original optical path, so that the single blue laser tube outputs two specific wavelength lasers; a controller adjusts the angle of the plane reflector to cause it to reflect lasers of different wavelengths; a laser output characteristic measurement system measures the output power and spectral characteristics of the two lasers of different wavelengths; and the controller plots the gain spectrum of the laser operating band.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor lasers, and more particularly, relates to a tunable dual-wavelength laser output device. Background Art

[0002] Dual-wavelength laser sources play a vital role in precision measurement, spectroscopy, and cutting-edge optical research. They can be used for interferometry, nonlinear frequency conversion, and the generation of coherent radiation in the mid-infrared and terahertz bands. These applications have not only advanced scientific research but also enabled the practical application of numerous new technologies, spanning a wide range of fields from fundamental research to industrial production.

[0003] In interferometry, especially in eliminating phase ambiguity and improving measurement accuracy, using dual-wavelength lasers, the interferometer can accurately calculate the optical path difference by measuring the phase difference between the two wavelengths of light in the target and reference paths. Interference signals of different wavelengths can be used in combination to improve the resolution and range of the measurement. In nonlinear optical processes, two wavelengths of laser light can interact in a nonlinear medium to generate mid-infrared photons corresponding to their frequency difference. Terahertz radiation has important applications in imaging, communications, security scanning, and material analysis. Coherent radiation in the terahertz band can be generated by the difference frequency or sum frequency process of two wavelengths of laser light in nonlinear materials. Through dual-wavelength laser excitation, nonlinear crystals can produce broadband mid-infrared spectra, which are widely used in laser spectroscopy, medical imaging, chemical sensing and other fields.

[0004] In coherent control and photon modulation, dual-wavelength laser sources can be used to generate and manipulate quantum states, such as entangled states or superradiant states. Control of these quantum states has important applications in quantum computing, quantum communication, and quantum sensing. In ultrafast laser systems, dual-wavelength lasers can be used to generate and control ultrashort laser pulses, which are used for ultrafast dynamics research, time-resolved spectroscopy, and materials science.

[0005] The linewidth requirements for dual-wavelength lasers typically depend on the specific application, but narrow linewidth is generally preferred to ensure high coherence, improve measurement accuracy, increase nonlinear frequency conversion efficiency, and improve signal quality. In some high-precision applications, such as spectroscopy or quantum optics, lasers may require ultra-narrow linewidth to meet stringent performance requirements.

[0006] Dual-wavelength laser light sources rely on precise wavelength selection and tuning, and the gain spectrum directly affects the output power and wavelength stability of the laser. Complete gain spectrum acquisition plays a key role in applications that require precise gain matching during nonlinear frequency conversion. The traditional method of generating dual-wavelength lasers is to use semiconductor lasers to pump crystals to produce two lasers with different wavelengths. It can be divided into two methods: using a single crystal to achieve dual-wavelength output by using the output mirror's reflectivity difference for different wavelengths; using dual crystals to output different wavelength lasers; and achieving dual-wavelength output through an optical parametric oscillator.

[0007] In the above method, when dual lasers with similar output wavelengths are used, the control is more complicated. Due to the use of crystals, it has high requirements for pump light. In addition, when dual-wavelength lasers are output through crystals, the laser line width is usually wide without control, which is not conducive to precision applications. Summary of the Invention

[0008] In response to the defects of the related art, the purpose of the present invention is to provide a tunable dual-wavelength laser output device, which aims to solve the problems of complex regulation, high requirements for pump light, and wide laser linewidth when the dual-wavelength laser outputs two lasers with similar wavelengths, as well as the difficulty in obtaining the complete gain spectrum of the laser light source.

[0009] To achieve the above objectives, the present invention provides a tunable dual-wavelength laser output device, comprising: a blue laser single tube, a beam fast and slow axis collimation system, a dual-wavelength spectrometer beamwidth compression system, a laser output characteristic measurement system, and a controller;

[0010] The light beam fast and slow axis collimation system is used to convert the light beam emitted by the blue laser single tube into collimated light;

[0011] The dual-wavelength spectroscopic beamwidth compression system includes two beam reflectors, two beam expansion subsystems, a transmission grating, and two plane reflectors. Each beam reflector is used to intercept a portion of collimated light and enter the corresponding beam expansion subsystem for beam expansion, while the remaining collimated light enters the laser output characteristic measurement system. The transmission grating is used to diffract the expanded light beam and output it to the plane reflectors. The two plane reflectors are used to reflect the vertically incident laser light and return it along the original optical path to the blue laser tube, so that the blue laser tube outputs two specific wavelength lasers.

[0012] The controller is connected to the plane reflector and is used to adjust the angle of the plane reflector so as to reflect laser beams of different wavelengths output by the transmission grating;

[0013] The laser output characteristic measurement system is used to measure the output power and spectral characteristics of two lasers with different wavelengths;

[0014] The controller is also connected to the laser output characteristic measurement system and is used to draw the gain spectrum of the blue laser single tube in the working band according to the output power and spectral characteristics of different wavelengths obtained by the laser output characteristic measurement system.

[0015] Optionally, the two beam reflectors are arranged on both sides of the collimated light entering the laser output characteristic measurement system, and are used to intercept the edge beams of the collimated light output by the beam fast and slow axis collimation system for wavelength locking and linewidth compression.

[0016] Optionally, the reflecting surface of the beam reflector is at 45° to the incident light, and is used to deflect the incident laser by 90°.

[0017] Optionally, the controller is also connected to the beam reflector to control the movement of the beam reflector to change the proportion of intercepting the laser beam.

[0018] Optionally, the beam reflector is one of a triangular prism, a plane reflector, a dielectric film reflector, a super reflector, a laser line reflector, and an elliptical reflector.

[0019] Optionally, the light beam fast-slow axis collimation system includes an aspherical cylindrical lens and a plano-convex cylindrical lens;

[0020] The aspherical cylindrical lens is a fast axis collimator, used to collimate the fast axis of the blue laser single tube;

[0021] The plano-convex cylindrical lens is a slow-axis collimating lens, the curved surface direction of which is perpendicular to the aspherical cylindrical lens, and is used to collimate the slow axis of the blue laser single tube.

[0022] Optionally, the beam expansion subsystem includes a lens pair consisting of a plano-concave spherical lens and a plano-convex spherical lens;

[0023] The focal points of the plano-concave spherical lens and the plano-convex spherical lens coincide with each other, and the focal length of the plano-convex spherical lens is greater than the absolute value of the focal length of the plano-concave spherical lens.

[0024] Optionally, the tunable dual-wavelength laser output device further includes an optical path deflection mirror for converging the two laser beams onto the same transmission grating.

[0025] Optionally, the laser output characteristic measurement system includes a plane spectrometer, a spectrometer and a power meter;

[0026] The plane beam splitter is at 45° to the incident light;

[0027] The spectrometer is placed at the right end of the plane beam splitter to receive the reflected light and detect the wavelength and line width of the output light beam;

[0028] The power meter is placed at the lower end of the plane beam splitter and is perpendicular to the transmitted light, and is used to detect the power of the received light beam.

[0029] Compared with the prior art, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

[0030] 1. The present invention provides a tunable dual-wavelength laser output device. This device uses a beam reflector to intercept and split a beam into three parts. Each of the intercepted beams passes through a transmission grating to select a specific wavelength. A plane reflector then selectively reflects the different wavelengths back to a single blue laser tube, achieving a competitive advantage and enabling high-power laser output at this wavelength from a single laser tube. By precisely controlling the angle of the reflector behind the grating, the laser can provide stable dual-wavelength output, achieving tunability of the output wavelengths. Adjustment is simple, the laser source requirements are low, and the beam has a narrow linewidth. This device addresses the complex control, high pump light requirements, and wide laser linewidth of dual-wavelength lasers with similar wavelengths. It flexibly adapts to diverse application requirements and maintains high performance under varying environmental conditions. Furthermore, a laser output characteristic measurement system measures the output power and spectral characteristics of the two lasers of different wavelengths. By continuously varying the output laser wavelength, a controller can plot the laser's gain spectrum within the operating band, thus resolving the difficulty in obtaining a complete gain spectrum of a laser source due to complex wavelength tuning. The tunable dual-wavelength laser output device of this solution can realize dual-wavelength laser output with a complete tunable narrow-linewidth gain spectrum.

[0031] 2. This invention provides a tunable dual-wavelength laser output device. A controller controls a plane reflector for wavelength tuning and a power meter for power monitoring. This laser output device not only outputs tunable wavelengths but also measures gain spectra at different wavelengths. This device can monitor the gain characteristics of the laser output device in real time, optimizing the power and coherence of the laser output to meet the needs of specific applications and ensure the highest efficiency at all wavelengths. For dual-wavelength lasers, understanding the gain spectrum can further assist in adjusting the power balance and coherence between the two wavelengths.

[0032] 3. This invention provides a tunable dual-wavelength laser output device that integrates optical components such as gratings and reflectors, reducing system size and improving overall stability. Compared with traditional methods using pump crystals, this device facilitates wavelength adjustment and gain spectrum measurement, making it suitable for use in a variety of experimental environments without the need for complex calibration and adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic structural diagram of a tunable dual-wavelength laser output device provided by the present invention;

[0034] Figure 2 1 is a schematic structural diagram of the slow axis of the collimation system provided by the present invention;

[0035] Figure 3 1 is a schematic structural diagram of the fast axis of the collimation system provided by the present invention;

[0036] Figure 4 is a schematic diagram of the light splitting structure provided by the present invention;

[0037] Figure 5 Schematic diagram of the first optical path of the dual-wavelength spectroscopic optical bandwidth compression system provided by the present invention;

[0038] Figure 6 Schematic diagram of the second optical path of the dual-wavelength spectroscopic optical bandwidth compression system provided by the present invention;

[0039] Figure 7 It is a schematic diagram of the laser output characteristic measurement system provided by the present invention.

[0040] The reference numerals in the above figures are the same, and the reference numerals in the figures are: 1. blue light laser single tube, 2. aspheric cylindrical lens, 3. plano-convex cylindrical lens, 4. first triangular prism, 5. third plane reflector, 6. first plano-concave spherical lens, 7. first plano-convex spherical lens, 8. transmission grating, 9. first plane reflector, 10. second triangular prism, 11. second plano-concave spherical lens, 12. second plano-convex spherical lens, 13. second plane reflector, 14. plane beam splitter, 15. spectrometer, 16. power meter. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0042] The contents involved in the above embodiment are described below in conjunction with a preferred embodiment.

[0043] A tunable dual-wavelength laser output device, comprising: a blue laser single tube 1, a beam fast-slow axis collimation system, a dual-wavelength splitting beamwidth compression system, a laser output characteristic measurement system, and a controller (not shown);

[0044] The light beam fast and slow axis collimation system is used to convert the light beam emitted by the blue laser single tube 1 into collimated light;

[0045] The dual-wavelength spectroscopic beamwidth compression system includes two beam reflectors, two beam expansion subsystems, a transmission grating 8, and two plane reflectors. Each beam reflector is used to intercept a portion of the collimated light and enter the corresponding beam expansion subsystem for beam expansion, while the remaining collimated light enters the laser output characteristic measurement system. The transmission grating 8 diffracts the expanded light beam and outputs it to the plane reflectors. The two plane reflectors are used to reflect the vertically incident laser light and return it along the original optical path to the blue laser single tube 1, so that the blue laser single tube 1 outputs two specific wavelength lasers.

[0046] The controller is connected to the plane reflector and is used to adjust the angle of the plane reflector so that it reflects laser beams of different wavelengths output by the transmission grating 8;

[0047] The laser output characteristic measurement system is used to measure the output power and spectral characteristics of two lasers with different wavelengths;

[0048] The controller is also connected to the laser output characteristic measurement system and is used to draw the gain spectrum of the blue laser single tube in the working band according to the output power and spectral characteristics of different wavelengths obtained by the laser output characteristic measurement system.

[0049] like Figure 1 、 Figure 4 As shown, as the first step in dual-wavelength linewidth compression, the collimated beam must be split. The laser light output by the blue laser tube 1 is collimated by the fast-slow axis collimation system and then split into three beams by the first beam reflector 4 and the second beam reflector 10. The left and right beams are reflected and serve as the input light for the dual-wavelength linewidth compression system. The first beam enters the first beam expansion subsystem, where it is expanded and emitted onto the transmission grating 8. The second beam enters the second beam expansion subsystem, where it is also expanded and emitted onto the transmission grating 8, where it is diffracted and output. Because different wavelengths have different diffraction angles when passing through the transmission grating 8, the first and second plane reflectors 9 and 13, located behind the transmission grating 8, only reflect the vertically incident laser light of a specific wavelength. The controller rotates the first and second plane reflectors 9 and 13 to orthogonal to the desired wavelength of the laser light after passing through the transmission grating 8. This gives the desired wavelength of laser light a competitive advantage within the external cavity, allowing the blue laser tube 1 to output high-power laser light of this wavelength. The laser output from the blue laser tube 1 is now of two specific wavelengths. The laser output characteristic measurement system measures the output power and spectral characteristics of the two different wavelength lasers. The tunable dual-wavelength laser output device provided in this embodiment achieves tunable dual-wavelength output, allowing the coherence between the two wavelengths to be controlled by precisely adjusting the wavelengths. This is crucial for interferometry, phase-sensitive applications, and multi-wavelength coherent detection systems.

[0050] At the same time, the laser output characteristic measurement system of the present invention measures the output power and spectral characteristics of two different wavelength lasers of the laser output device. Since the laser output device has different gains for different wavelengths, while the beam reflector is fixed, that is, the intercepted light ratio remains unchanged, the controller changes the angle of the plane reflector to continuously change the output laser wavelength. Based on the output power and spectral characteristics of different wavelengths, the gain spectrum of the laser in the operating band can be plotted, thus solving the problem of difficulty in obtaining a complete gain spectrum of the laser light source due to complex wavelength tuning. The tunable dual-wavelength laser output device of this solution can achieve dual-wavelength laser output with a complete tunable narrow-linewidth gain spectrum.

[0051] The blue laser diode 1 is an uncollimated edge-emitting blue semiconductor laser diode with a rated output wavelength of 445 nm, a fast-axis divergence half-angle of 22.5°, a beam length of 1 μm, a slow-axis divergence half-angle of 4°, and a beam length of 50 μm. Based on the basic characteristics of semiconductor laser diodes, their fast-axis output is a single transverse mode, while their slow-axis output is multiple longitudinal modes. Because diodes heat up easily during normal operation, and this temperature affects the output wavelength and power of the laser during operation, they must be cooled to maintain stable operating conditions to prevent any impact on the output state and the introduction of extraneous variables into the gain spectrum measurement.

[0052] The grating in this embodiment is a transmission grating, which has high optical transparency and high refractive efficiency, plays a good transmission and diffraction role in the optical path, and can separate lasers of different wavelengths with low loss.

[0053] Optionally, the two beam reflectors are arranged on both sides of the collimated light entering the laser output characteristic measurement system, and are used to intercept the edge beams of the collimated light output by the beam fast and slow axis collimation system for wavelength locking and linewidth compression.

[0054] Optionally, the controller is also connected to the beam reflector to control the movement of the beam reflector to change the proportion of intercepting the laser beam.

[0055] The light beam incident on the first beam reflector 4 is defined as the first beam, the light beam incident on the second beam reflector 10 is defined as the second beam, and the light beam entering the laser output characteristic measurement system is defined as the third beam; the first beam reflector 4 and the second beam reflector 10 can be set on the same side or on both sides of the third beam.

[0056] like Figure 1 As shown, the first and second beam reflectors 4 and 10 are symmetrically positioned on either side of the third beam, intercepting the edge beams for wavelength locking and linewidth compression, while retaining the higher-intensity portion of the central beam for output. Compared to a configuration where both prisms are located on the same side of the beam, these mirrors can move independently to adjust the intercepted beam ratio, thereby regulating the intensity ratio of the dual-wavelength lasers in the output beam.

[0057] Optionally, in the above optical path, the reflecting surface of the beam reflector is at 45° to the incident light, so as to deflect the incident laser by 90°.

[0058] The beam reflector is also used to adjust the optical paths of the two beams.

[0059] Optionally, the beam reflector is one of a triangular prism, a plane reflector, a dielectric film reflector, a super reflector, a laser line reflector, and an elliptical reflector.

[0060] To facilitate movement, the selected beam reflector is a triangular prism. The collimated light beam is divided into three parts along the slow axis by two triangular prisms. Among them, the first triangular prism 4 is placed on the left side of the third light beam, and the second triangular prism 10 is placed on the right side of the third light beam, and both use edge beams; the hypotenuse of the triangular prism reflects the light beam, and itself can move left and right along the direction perpendicular to the slow axis light beam to change the splitting ratio. In this example, in order to achieve higher output and better linewidth compression, the light beam power intercepted by a single triangular prism should be between 10% and 20% of the total power, that is, the light power entering the two wavelength selection light paths is changed.

[0061] Optionally, the light beam fast-slow axis collimation system includes an aspherical cylindrical lens 2 and a plano-convex cylindrical lens 3;

[0062] The aspherical cylindrical lens 2 is a fast axis collimator, used to collimate the fast axis of the blue laser single tube 1;

[0063] The plano-convex cylindrical lens 3 is a slow-axis collimating lens, the curved surface direction of which is perpendicular to the aspherical cylindrical lens, and is used to collimate the slow axis of the blue laser single tube 1 .

[0064] The aspheric cylindrical lens 2 collimates the fast axis of the blue light single tube with a larger divergence angle. The size of the light spot after collimation is determined by the focal length of the fast axis collimator. The larger the focal length, the larger the collimated light and the smaller the divergence angle after collimation. The luminous characteristics of a semiconductor laser single tube have a large fast axis divergence angle and are more sensitive to the spherical aberration of the lens. Therefore, an aspheric cylindrical lens with a larger numerical aperture is selected to minimize the spherical aberration and completely collimate the fast axis laser.

[0065] Reference Figure 1 、 Figure 2 、 Figure 3 In this embodiment, aspheric cylindrical lens 2 is a large-aperture aspheric cylindrical lens with a focal length of 4.5 mm and a numerical aperture of 0.64, which collimates the fast-axis beam. Plano-convex cylindrical lens 3 is a conventional cylindrical lens with a focal length of 40 mm and a size of 20 mm x 20 mm. Its front focal plane is located at the laser diode's emission point, converting the slow-axis beam from divergent light to collimated light with a low divergence angle. Because the fast and slow axes are collimated separately, and the collimating lenses have different focal lengths, the length of the collimated light spot along the slow axis is actually longer than the length of the fast-axis beam.

[0066] The curved surface direction of the plano-convex cylindrical lens 3 is perpendicular to the aspheric cylindrical lens 2. Since the slow-axis divergence angle of the light beam is small, an ordinary plano-convex spherical lens is selected as the collimator for cost considerations. To achieve a better collimation effect, the focal length of the slow-axis collimator should theoretically be as large as possible. However, considering the size of the lens and the volume of the overall device, the focal length should be less than 100 mm.

[0067] Optionally, the beam expansion subsystem includes a lens pair consisting of a plano-concave spherical lens and a plano-convex spherical lens;

[0068] The focal points of the plano-concave spherical lens and the plano-convex spherical lens coincide with each other, and the focal length of the plano-convex spherical lens is greater than the absolute value of the focal length of the plano-concave spherical lens.

[0069] The lens pair is in a geometrically overlapping relationship, with the focal length relationship being that the focal length of the convex lens is greater than the absolute value of the focal length of the concave lens. This serves to amplify the output light beam, reducing its divergence angle by a corresponding multiple to increase its collimation and reduce the diffraction angle deviation caused by its own divergence angle when incident on the grating.

[0070] Optionally, the tunable dual-wavelength laser output device further includes an optical path deflection mirror for converging the two laser beams onto the same transmission grating.

[0071] In this embodiment, the optical path deflecting mirror is a third plane mirror 5. In order to reduce the size of the device and reduce the cost of the device, the third plane mirror 5 is used to deflect one of the optical paths by 90°, so that the two lasers are converged on the same grating. However, it should be noted that the two light spots do not overlap.

[0072] Optionally, the laser output characteristic measurement system includes a plane spectrometer, a spectrometer and a power meter;

[0073] The plane beam splitter is at 45° to the incident light;

[0074] The spectrometer is placed at the right end of the plane beam splitter to receive the reflected light and detect the wavelength and line width of the output light beam;

[0075] The power meter is placed at the lower end of the plane beam splitter and is perpendicular to the transmitted light, and is used to detect the power of the received light beam.

[0076] Furthermore, the splitting ratio of the plane beam splitter is 99:1, and the power meter obtains most of the laser energy.

[0077] Reference Figure 1 、 Figure 5The first wavelength selection optical path is composed of a first triangular prism 4, a third plane reflector 5, a first plano-concave spherical lens 6, a first plano-convex spherical lens 7, a transmission grating 8, and a first plane reflector 9. After being reflected by the first triangular prism 4, the light beam is reflected again by a third plane reflector 5 with a fixed position and a reflecting surface perpendicular to the inclined surface of the triangular prism. Except for the change in the propagation direction, the other characteristics remain unchanged. Afterwards, the light beam is amplified twice by an inverted Galilean telescope system composed of the first plano-concave spherical lens 6 and the first plano-convex spherical lens 7. Compared with the Kepler telescope system composed of two convex lenses, the optical path of the concave-convex lens combination is smaller and more space-saving. Considering that the light has to enter the grating, the magnification is also limited. The focal length of the lens group selected in this embodiment is -20mm and 100mm, which magnifies the light beam by 5 times and reduces the beam divergence angle by 5 times accordingly. The slow axis direction can reach 10 -5 rad level. After amplification, the light beam enters the diffraction grating 8 at a fixed angle α. According to the diffraction formula,

[0078] d(sinθ+sinα)=mλ (1)

[0079] The number of selected grating lines is fixed; the higher the number of transmission grating lines, the stronger its spectral resolution and the better its linewidth reduction effect. Therefore, the wavelength corresponds to the diffraction angle θ after passing through the grating. By adjusting the first plane reflector 9 placed after the grating so that it is perpendicular to the diffraction angle of the desired wavelength, this portion of light can return to the grating along its original path and undergo another diffraction. After that, according to the principle of optical path reversibility, it directly returns to the blue laser single tube 1, completing the wavelength selection step. The remaining wavelength beams become stray light when diffracted by the transmission grating 8. Because the returning wavelength beam gains an advantage in competing with the beam under the influence of the external cavity, the diode output laser will be converted to contain only this wavelength, with a linewidth of less than 0.1nm. Its output power depends on the gain at this wavelength. The above is the implementation principle of narrow linewidth laser.

[0080] Reference Figure 1 、 Figure 6 The second wavelength selection optical path consists of a second triangular prism 10, a second plano-concave spherical lens 11, a second plano-convex spherical lens 12, a transmission grating 8, and a second plane mirror 13. This optical path is independent of the first wavelength selection optical path, with the light beam intercepted by the triangular prism. Unlike the first optical path, since the same transmission grating is used, the optical path does not need to pass through a plane mirror to deflect the laser transmission direction. After beam expansion by the lens pair, the second light beam enters different areas of the transmission grating 8 at a fixed incident angle. The angle of the second plane mirror 13 at the end of the optical path is perpendicular to the desired wavelength diffraction angle, completing the dual-wavelength single grating narrow linewidth output. Starting from the center wavelength of 445nm, the angle of the plane mirror behind the grating is deflected by a very small angle, and the output light wavelength also changes accordingly, thus achieving wavelength tuning function.

[0081] Reference Figure 1 、 Figure 7 The laser output characteristics measurement system includes a plane beamsplitter 14, a spectrometer 15, and a power meter 16. Plane beamsplitter 14 splits the collimated laser light, which is not split by the two triangular prisms, into two beams. The beamsplitter reflects 0.1% of the blue laser light. The reflected light is perpendicularly incident on the spectrometer 15 to the right of the plane beamsplitter, while the transmitted light is perpendicularly incident on the power meter 16 below. This allows for simultaneous observation and measurement of the output laser's spectrum and power characteristics. While wavelength tuning is in progress, the laser gain spectrum within 4 nm of the center wavelength can be accurately measured based on feedback from the power meter and spectrometer.

[0082] The embodiments of the present invention combine an optical lens with a diffraction grating, using wavelength feedback as the basic principle. By constructing two optical paths, the transmission grating selects a specific wavelength laser, and outputs a highly coherent dual-wavelength laser, achieving a combination of wavelength tunability, dual-wavelength output capability, and gain spectrum measurement capabilities. This solves the problem of complex control, high pump light requirements, and wide laser linewidth when dual-wavelength lasers output two lasers with similar wavelengths, as well as the difficulty in obtaining a complete gain spectrum of the laser source. The design not only provides flexibility and versatility, but also excels in various high-precision optical applications. This enables the laser output device to flexibly adapt to different application requirements, enabling the selection of the optimal wavelength for operation in precision spectral analysis, optical communications, and nonlinear optical processes. Wavelength tuning allows for precise control of the coherence of the dual-wavelength laser, which is very beneficial for applications requiring precise phase control, such as interferometry and quantum optics. In interferometry and nonlinear optical experiments, this laser design can significantly improve system performance and the reliability of experimental results. When generating coherent radiation in different frequency bands of the mid-infrared or terahertz bands, the laser can adjust the output wavelength to optimize the frequency conversion efficiency.

[0083] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A tunable dual-wavelength laser output device, characterized in that: include: Blue laser single tube, beam fast and slow axis collimation system, dual-wavelength spectrometer beam width compression system, laser output characteristics measurement system and controller; The light beam fast and slow axis collimation system is used to convert the light beam emitted by the blue laser single tube into collimated light; The dual-wavelength spectroscopic linewidth compression system includes two beam reflectors, two beam expansion subsystems, a transmission grating, and two plane reflectors. The two beam reflectors are arranged on both sides of the collimated light entering the laser output characteristic measurement system, and are used to intercept the edge beams of the collimated light output by the fast-slow axis collimation system for wavelength locking and linewidth compression. Part of the collimated light enters the corresponding beam expansion subsystem for beam expansion, and the remaining collimated light enters the laser output characteristic measurement system. The transmission grating is used to diffract the expanded beam and output it to the plane reflectors. The two plane reflectors are used to reflect the vertically incident laser light and return it along the original optical path to the blue laser single tube, so that the blue laser single tube outputs two specific wavelength lasers. The controller is connected to the plane reflector and is used to adjust the angle of the plane reflector so as to reflect laser beams of different wavelengths output by the transmission grating; The laser output characteristic measurement system is used to measure the output power and spectral characteristics of two lasers with different wavelengths; The controller is also connected to the laser output characteristic measurement system and is used to draw the gain spectrum of the blue laser single tube in the working band according to the output power and spectral characteristics of different wavelengths obtained by the laser output characteristic measurement system; Wherein, the light beam fast and slow axis collimation system includes an aspherical cylindrical lens and a plano-convex cylindrical lens; The aspherical cylindrical lens is a fast axis collimator, used to collimate the fast axis of the blue laser single tube; The plano-convex cylindrical lens is a slow-axis collimating lens, the curved surface direction of which is perpendicular to the aspherical cylindrical lens, and is used to collimate the slow axis of the blue laser single tube.

2. The tunable dual-wavelength laser output device according to claim 1, wherein: The reflecting surface of the beam reflector is at an angle of 45° to the incident light, and is used to deflect the incident laser by 90°.

3. The tunable dual-wavelength laser output device according to claim 2, wherein: The controller is also connected to the beam reflecting mirror and is used to control the movement of the beam reflecting mirror to change the proportion of intercepting the laser beam.

4. The tunable dual-wavelength laser output device according to claim 1, wherein: The beam reflector is one of a triangular prism, a plane reflector, a dielectric film reflector, a super reflector, a laser line reflector, and an elliptical reflector.

5. The tunable dual-wavelength laser output device according to claim 1, wherein: The beam expansion subsystem includes a lens pair consisting of a plano-concave spherical lens and a plano-convex spherical lens; The focal points of the plano-concave spherical lens and the plano-convex spherical lens coincide with each other, and the focal length of the plano-convex spherical lens is greater than the absolute value of the focal length of the plano-concave spherical lens.

6. The tunable dual-wavelength laser output device according to claim 1, wherein: The tunable dual-wavelength laser output device further comprises an optical path deflecting reflector for converging two paths of laser light onto the same transmission grating.

7. The tunable dual-wavelength laser output device according to claim 1, wherein: The laser output characteristic measurement system includes a plane spectroscope, a spectrometer and a power meter; The plane beam splitter is at 45° to the incident light; The spectrometer is placed at the right end of the plane beam splitter to receive the reflected light and detect the wavelength and line width of the output light beam; The power meter is placed at the lower end of the plane beam splitter and is perpendicular to the transmitted light, and is used to detect the power of the received light beam.

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