A multi-wavelength output tunable laser

Abstract

The utility model provides a kind of multi-wavelength output tunable laser, including pump source, reflection unit, optical path unit: reflection unit includes first reflector, second reflector and third reflector, wherein, first reflector is arranged in the propagation direction of pump source optical path, and it is located in the rear end of pump source;Second reflector is located in the reflected light path of the first reflector, and third reflector is located in the transmission light path of the second reflector;First reflector, second reflector and third reflector have different reflectivity;Optical path unit includes first optical path unit, second optical path unit and third optical path unit, wherein, first optical path unit is arranged on the transmission light path of the first reflector, second optical path unit is arranged on the single optical path of the second reflector, and the third optical path unit is arranged on the reflected light path of the third reflector.

Description

Technical Field

[0001] This utility model relates to the field of laser equipment technology, specifically to a multi-wavelength output tunable laser. Background Technology

[0002] Emerald crystal (Cr3+:BeAl2O4) is a laser material possessing excellent properties such as high power and wide tunability. Due to its tunability, high gain, and superior temperature characteristics, emerald lasers have received widespread attention since their emergence. Their basic output spectrum ranges from visible to near-infrared (701-858 nm), making them widely applicable in numerous cutting-edge research fields, including space remote sensing, medicine, optical storage, spectroscopy, and nonlinear optics.

[0003] Alexandrite crystal pumping refers to the technique of using various visible light sources (such as red LD, green laser, yellow laser, blue LD, etc.) to pump Alexandrite crystals in order to achieve tunable laser output.

[0004] The existing emerald crystal technology has the following shortcomings: 1. Although emerald crystals have a wide absorption band and can be pumped by various wavelengths, their absorption peak is located near 590nm. Pump sources in this band are expensive and their power cannot be very high.

[0005] 2. Existing emerald lasers cannot output multiple wavelengths simultaneously, which affects the effect of use, especially in the field of medical aesthetics, where simultaneous output of multiple wavelengths can achieve twice the result with half the effort in cosmetic effects. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of the existing technology and solve at least one of the above-mentioned technical problems by providing a multi-wavelength output tunable laser.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A multi-wavelength output tunable laser, comprising: Pump source; The reflection unit includes a first reflector, a second reflector, and a third reflector. The first reflector is positioned in the propagation direction of the pump source optical path and is located at the rear end of the pump source. The second reflector is located in the reflected optical path of the first reflector, and the third reflector is located in the transmitted optical path of the second reflector. The first, second, and third reflectors have different reflectivities. Optical path unit: includes a first optical path unit, a second optical path unit and a third optical path unit, wherein the first optical path unit is disposed on the transmission optical path of the first reflector, the second optical path unit is disposed on the isolated optical path of the second reflector, and the third optical path unit is disposed on the reflection optical path of the third reflector.

[0008] In some embodiments of this application, along the propagation direction of the optical path, the pump source sequentially includes: a laser diode, a coupling lens group, a half-wave plate, and a self-frequency doubling crystal; the first reflector is disposed at the rear end of the self-frequency doubling crystal.

[0009] In some embodiments of this application, the first reflector forms a 45° angle with the propagation direction of the pump source optical path, and the transmittance of the first reflector is 67%.

[0010] In some embodiments of this application, the second reflector forms a 45° angle with the propagation direction of the reflective optical fiber of the first reflector, and the light transmittance of the second reflector is 50%.

[0011] In some embodiments of this application, the propagation direction of the third reflecting mirror and the reflecting optical fiber of the second reflecting mirror are at a 45° angle, and the third reflecting mirror is a total reflection mirror.

[0012] In some embodiments of this application, along the propagation direction of the optical path, the first optical path unit, the second optical path unit, and the third optical path unit each sequentially include: The system comprises a first emerald laser reflector, an emerald crystal, a second emerald laser reflector, a third emerald laser reflector, and an emerald laser output mirror; the first and second emerald laser reflectors are concave mirrors, and the third emerald laser reflector is a plane mirror. The concave surfaces of the first emerald laser reflector and the second emerald laser reflector are opposite each other, and the first emerald laser reflector is tilted relative to the propagation of transmitted light from the first reflector; the emerald crystal is disposed in the transmission optical path of the first emerald laser reflector, and the third emerald laser reflector is disposed in the emerald crystal; the emerald laser output mirror is disposed in the reflection optical path of the first emerald laser, and the third emerald laser reflector is disposed in the reflection optical path of the second emerald laser reflector. The first emerald laser reflector of the first optical path is disposed in the transmission optical path of the first reflector, the second emerald laser reflector of the second optical path is disposed in the reflection optical path of the second reflector, and the third emerald laser reflector of the third optical path is disposed in the reflection optical path of the third reflector.

[0013] In some embodiments of this application, the first optical path unit, the second optical path unit, and the third optical path unit further include: a focusing lens; The focusing lens of the first optical path unit is disposed between the first emerald laser reflector and the first reflector in the first optical path; The focusing lens of the second optical path unit is disposed between the first emerald laser reflector and the second reflector in the second optical path; The focusing lens of the third optical path unit is positioned between the first emerald laser reflector and the third reflector in the third optical path.

[0014] In some embodiments of this application, the first optical path unit, the second optical path unit, and the third optical path unit further include a frequency multiplication unit.

[0015] In some embodiments of this application, the frequency doubling unit includes a first frequency doubling crystal and a second frequency doubling crystal.

[0016] In some embodiments of this application, the first optical path unit, the second optical path unit, and the third optical path unit all further include a resonant element, which is disposed between the second emerald laser reflector and the third emerald laser reflector.

[0017] Compared with existing technologies, the technical advantages of the multi-wavelength output tunable laser provided by this utility model are as follows: By setting up a multi-optical-path structure and configuring different optical devices, multi-channel, multi-wavelength output can be achieved; Using yellow laser light output from a pump source as the pump source for a tunable sapphire laser is not only cost-effective, but also achieves high optical-optical efficiency because it can be aligned with the absorption peak of the sapphire crystal. At the same time, the quantum loss of the pump light and the output light is also small, which can improve the output performance of the sapphire laser and meet various needs in practical applications. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the laser optical path structure provided in an embodiment of this application; In the above figures: 1. First optical path; 2. Second optical path; 3. Third optical path; 4. Laser diode; 5. Power transmission optical fiber; 6. Coupled lens group; 7. Half-wave plate; 8. Self-frequency doubling crystal; 9. First reflecting mirror; 10. First optical path focusing lens; 11. First optical path emerald laser reflector; 12. First optical path emerald crystal; 13. First optical path emerald laser second reflector; 14. First optical path emerald laser third reflecting mirror; 15. First optical path tuning element; 16. First optical path emerald laser output mirror; 17. First optical path, first frequency doubling crystal; 18. First optical path, second frequency doubling crystal; 19. Second reflecting mirror; 20. Second optical path focusing lens; 21. Second optical path emerald laser first reflecting mirror; 22. Second optical path emerald crystal; 23. Second optical path emerald laser second reflector; 24. Second optical path emerald laser third reflecting mirror; 25. Second optical path tuning element; 26. Second optical path emerald laser output mirror; 27. Second optical path, first frequency doubling crystal; 28. Second optical path, second frequency doubling crystal; 29. The third total internal reflection mirror; 30. Third optical path focusing lens; 31. Third optical path emerald laser first reflecting mirror; 32. Third-path emerald crystal; 33. Third optical path emerald laser second reflector; 34. Third optical path emerald laser third reflecting mirror; 35. Third optical path tuning element; 36. Third optical path emerald laser output mirror; 37. Third optical path, first frequency doubling crystal; 38. Second frequency doubling crystal for the third optical path. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be 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 illustrative of the present utility model and are not intended to limit the present utility model.

[0021] It should be noted that when a component is referred to as "set on" or "connected to" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0022] It should be understood that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0023] The terms "first" and "second" are used for descriptive purposes only and are not intended to imply relative importance.

[0024] Alexandrite crystal pumping refers to the technique of pumping an Alexandrite crystal using various visible light sources (such as red LDs, green lasers, yellow lasers, and blue LDs) to achieve tunable laser output. Alexandrite crystals have a wide absorption band (400–700 nm) and a wide emission band (700–900 nm), supporting various pumping methods from red to blue light, making them suitable for high-power, high-efficiency, tunable laser systems.

[0025] There are many methods for pumping sapphire crystals, because sapphire crystals have a wide absorption band, and can absorb pump light in the range of 400-700nm. The commonly used pumping methods are: (1) Flash lamp pumping. Industrial processing and commercial medical sapphire lasers mostly use flash lamp pumping. This technology is relatively mature, but due to its imperfect absorption, the overall conversion efficiency of the laser is low, and the heat generation of the laser is also quite serious. (2) 635 / 680nm red LD pumping. Using LD to pump sapphire crystals can greatly improve the overall efficiency of the laser and realize the miniaturization of the laser. However, high-power 635 and 680nm LDs are not common at present, which greatly limits the output power of sapphire lasers. Moreover, the price of LDs in this band is also relatively expensive. (3) Blue-green laser pumping. Since emerald's absorption band covers the entire visible light spectrum, this crystal can be pumped by common visible light lasers such as 488nm argon ion lasers, copper vapor lasers, and 532nm green lasers. However, there is a large quantum defect between the pump light and the output light under this pumping method, which makes the thermal load of the laser more severe, thus affecting the output characteristics such as beam quality.

[0026] Self-frequency doubling laser crystals are created by doping nonlinear optical crystals with activating ions (usually Nd3+ or Yb3+), enabling them to simultaneously perform laser emission and nonlinear optical frequency doubling functions, generating fundamental infrared light while doubling its frequency.

[0027] Typical self-frequency doubling crystals include neodymium-doped yttrium aluminum tetraborate (NYAB), ytterbium-doped ytterbium-doped ytterbium tetraborate (Yb:YAB), and neodymium or ytterbium-doped calcium borate (Nd / Yb:RECOB).

[0028] Laser frequency doubling refers to the process of generating laser light with half the wavelength and double the frequency by passing it through a frequency doubling crystal (such as LBO, BBO, etc.). Emerald lasers have a wavelength tuning range of 701~858 nm. Tunable ultraviolet and deep ultraviolet lasers can be obtained through single or double frequency doubling, such as deep ultraviolet lasers with high coherence and high beam quality at wavelengths of 372 nm (744 nm second harmonic), 248 nm (744 nm third harmonic), and 193 nm (772 nm fourth harmonic).

[0029] This application proposes a multi-wavelength output tunable laser to address the shortcomings of existing technologies. Considering that sapphire exhibits a strong broad absorption peak centered at 590nm along the E / / b axis, this application provides a tunable sapphire laser pumped by a 594nm yellow light laser output from a self-frequency-doubling crystal near the 594nm wavelength. By frequency doubling the output tunable laser, simultaneous output of multiple wavelengths can be achieved.

[0030] A multi-wavelength output tunable laser includes a pump source, a reflection unit, and an optical path unit. The reflection unit includes a first reflector 9, a second reflector 19, and a third reflector 29.

[0031] In some embodiments, along the propagation direction of the optical path, the pump source sequentially includes: a laser diode 4, a coupling lens group 6, a half-wave plate 7, and a self-frequency doubling crystal 8; energy is transmitted between the laser diode 4 and the coupling lens group 6 through an energy transmission fiber 5; a first reflector 9 is disposed at the rear end of the self-frequency doubling crystal 8.

[0032] The first reflector 9 of the reflection unit is located in the propagation direction of the pump source optical path and is located at the rear end of the pump source; the second reflector 19 is located in the reflection optical path of the first reflector 9, and the third reflector 29 is located in the transmission optical path of the second reflector; the first reflector 9, the second reflector 19 and the third reflector 29 have different reflectivities.

[0033] For example, in some embodiments of this application, the first reflector 9 forms a 45° angle with the propagation direction of the relative pump source optical path, and the transmittance of the first reflector 9 is 67%. The second reflector 19 forms a 45° angle with the propagation direction of the reflective optical fiber of the first reflector 9, and the transmittance of the second reflector 19 is 50%. The third reflector 29 forms a 45° angle with the propagation direction of the reflective optical fiber of the second reflector 19, and the third reflector 29 is a total reflection mirror.

[0034] Optical path unit: includes a first optical path unit, a second optical path unit, and a third optical path unit, which respectively form the first optical path, the second optical path, and the third optical path. Among them, the first optical path unit is set on the transmission optical path of the first reflector 9, the second optical path unit is set on the isolated optical path of the second reflector 19, and the third optical path unit is set on the reflection optical path of the third reflector 29.

[0035] In some embodiments of this application, along the propagation direction of the optical path, the first optical path unit, the second optical path unit, and the third optical path unit each sequentially include: First emerald laser reflector, emerald crystal, second emerald laser reflector, third emerald laser reflector, emerald laser output mirror; the first and second emerald laser reflectors are concave mirrors, and the third emerald laser reflector is a plane mirror; The concave surfaces of the first emerald laser reflector and the second emerald laser reflector are opposite each other, and the propagation of the transmitted light from the first emerald laser reflector relative to the first reflector is tilted; an emerald crystal is disposed in the transmission light path of the first emerald laser reflector, and a third emerald laser reflector is disposed in the emerald crystal; an emerald laser output mirror is disposed in the reflection light path of the first emerald laser, and a third emerald laser reflector is disposed in the reflection light path of the second emerald laser reflector. The first emerald laser reflector is located in the transmission optical path of the first reflector, the second emerald laser reflector is located in the reflection optical path of the second reflector, and the third emerald laser reflector is located in the reflection optical path of the third reflector.

[0036] In some embodiments of this application, the first optical path unit, the second optical path unit, and the third optical path unit further include: a focusing lens; wherein: The focusing lens of the first optical path unit is positioned between the first emerald laser reflector and the first reflector. The focusing lens of the second optical path unit is positioned between the first emerald laser reflector and the second reflector; The focusing lens of the third optical path unit is positioned between the first emerald laser mirror and the third mirror.

[0037] In some embodiments of this application, the first optical path unit, the second optical path unit, and the third optical path unit further include a frequency doubling unit. The number of frequency doubling units can be set as needed. Each frequency doubling unit includes a first frequency doubling crystal and a second frequency doubling crystal.

[0038] In some embodiments of this application, the first optical path unit, the second optical path unit, and the third optical path unit all further include a resonant element, which is disposed between the second emerald laser mirror and the third emerald laser mirror.

[0039] The following describes the implementation structure of the laser provided in this application using a specific optical path configuration.

[0040] The 975nm laser diode pump source 4 emits pump light, which is transmitted through the power transmission fiber 5 and focused by the coupling lens group 6 to pump the self-frequency doubling crystal 5; the self-frequency doubling crystal 5 is a Yb:YCOB crystal with a crystal size of 3×3×10mm. 3 The doping concentration is selected as 30%. Both ends of the self-frequency doubling crystal 5 are polished. On the light-transmitting surface near the coupling lens group, an anti-reflection coating for the 975nm pump light emitted by the laser diode, and a total reflection coating for the 1188nm laser generated by the self-frequency doubling crystal 5, and the 594nm yellow laser generated by frequency doubling are deposited. On the light-transmitting surface away from the coupling lens group, a total reflection coating for the 1188nm laser generated by the self-frequency doubling crystal 5 absorbing the pump light output from the laser diode, and an anti-reflection coating for the 594nm yellow laser generated by frequency doubling are deposited. It is then wrapped with an indium sheet and placed in a heat sink, with the operating temperature controlled by a cooling circulating water system.

[0041] The self-frequency doubling crystal 5 absorbs 975nm pump light to form population inversion. Under the feedback of the resonance formed by the films at both ends of the self-frequency doubling crystal 5, 1188nm fundamental frequency light is generated. The 1188nm fundamental frequency light is frequency doubled by the nonlinear effect of the self-frequency doubling crystal 5 itself to generate 594nm yellow laser light.

[0042] A 594nm wavelength yellow laser is generated by frequency doubling. 33% of the total 594nm laser energy is incident on the first optical path after passing through the first reflector 99. After reflection by the first reflector 99, 67% of the total 594nm laser energy is incident on the second reflector 19. After reflection by the second reflector 19, 33% of the total 594nm laser energy is incident on the second optical path. After passing through the second reflector 19, 33% of the total 594nm laser energy is incident on the 45-degree total reflection mirror 29. After reflection by the 45-degree total reflection mirror 29, 34% of the total 594nm laser energy is incident on the third optical path.

[0043] The focusing lens 10 in the first optical path 1 has a focal length of 100mm, which focuses the yellow laser light passing through the 594nm focusing lens 10 into the emerald crystal 12 in the first optical path 1 for pumping. The emerald crystal 12 in the first optical path 1 is cut with Brewster angle and has a crystal size of 4×4×15mm. 3 After absorbing 594nm yellow laser light, population inversion occurs. As the pump energy increases, the gain exceeds the loss, thus generating spontaneous emission photons. The emerald resonator adopts a four-mirror ring cavity type. The first emerald laser reflecting mirror 11 and the second emerald laser reflecting mirror 13 in the first optical path 1 are concave mirrors with a radius of curvature of 100mm, and the concave surfaces are coated with a 700-860nm high-reflection film. The angle between the two mirrors is 15~20°. The third emerald laser reflecting mirror 14 in the first optical path 1 is a flat mirror, with one side coated with a 700-860nm high-reflection film. The emerald laser output mirror 16 in the first optical path 1 is a flat mirror, with one side coated with a 700-860nm partially transparent film. The transmittance is 5~20%; the tuning element 15 in the first optical path 1 is selected from two birefringent filters (BRF) with thicknesses of 5mm and 10mm respectively. The tunable output of the sapphire laser is achieved by rotating the BRF; the spontaneous emission photons generated by the sapphire crystal 12 in the first optical path 1 form a stable laser oscillation in the four-mirror ring resonator composed of the first sapphire laser first reflector 11, the second sapphire laser reflector 13, the third sapphire laser reflector 14 and the output mirror 16 in the first optical path 1, and the output mirror 16 in the first optical path 1. The output mirror 16 in the first optical path 1 outputs 744nm laser light.

[0044] Within the first optical path 1, both the first frequency-doubling crystal 17 and the second frequency-doubling crystal 18 are mounted on a movable platform. These two crystals can be inserted into and removed from the optical path electrically or manually. Both end faces of the first frequency-doubling crystal 17 and the second frequency-doubling crystal 18 within the first optical path 1 are polished. The two light-transmitting surfaces of the first frequency-doubling crystal 17 are coated with anti-reflection films for the emerald laser output from the first optical path 1 and its frequency-doubled laser. The second frequency-doubling crystal... The two light-transmitting surfaces of 18 are coated with anti-reflection films for the emerald laser output from the first optical path 1, as well as its frequency-doubled and third-doubled lasers. The 744nm laser output through the emerald laser output mirror 16 in the first optical path 1 can achieve 372nm frequency-doubled laser output when the first frequency-doubled crystal 17 in the first optical path 1 is in the optical path and the second frequency-doubled crystal 18 in the first optical path 1 is not in the optical path; when both the first frequency-doubled crystal 17 and the second frequency-doubled crystal 18 in the first optical path 1 are in the optical path, 248nm frequency-doubled laser output can be achieved.

[0045] The focusing lens 20 has a focal length of 100mm, which focuses the yellow laser light passing through the 594nm focusing lens 20 into the emerald crystal 22 in the second optical path 2 for pumping. The emerald crystal 22 in the second optical path 2 is cut with Brewster angle and has a crystal size of 4×4×15mm. 3 After absorbing 594nm yellow laser light, population inversion occurs. As the pump energy increases, the gain exceeds the loss, thus generating spontaneous emission photons. The emerald resonator adopts a four-mirror ring cavity type. The emerald laser first reflecting mirror 21 and the emerald laser second reflecting mirror 23 in the second optical path 2 are concave mirrors with a radius of curvature of 100mm, and the concave surfaces are coated with a 700-860nm high-reflection film. The included angle between the two mirrors is 15~20°. The emerald laser third reflecting mirror 24 in the second optical path 2 is a flat mirror, with one side coated with a 700-860nm high-reflection film. The emerald laser output mirror 26 in the second optical path 2 is a flat mirror, with one side coated with a 700-860nm partially transparent film. The transmittance is 5~20%; the tuning element 25 in the second optical path 2 is selected from two birefringent filters (BRF) with thicknesses of 5mm and 10mm respectively. The tunable output of the sapphire laser is achieved by rotating the BRF; the spontaneous emission photons generated by the sapphire crystal 22 in the second optical path 2 form a stable laser oscillation in the four-mirror ring resonator composed of the first sapphire laser mirror 21, the second sapphire laser mirror 23, the third sapphire laser mirror 24, and the second sapphire laser output mirror 26 in the second optical path 2, and output 756nm laser through the sapphire laser output mirror 26 in the second optical path 2.

[0046] Within the second optical path 2, both the first frequency-doubling crystal 27 and the second frequency-doubling crystal 28 are mounted on a movable platform. These two crystals can be inserted into and removed from the optical path electrically or manually. Both end faces of the first frequency-doubling crystal 27 and the second frequency-doubling crystal 28 within the second optical path 2 are polished. The two light-transmitting surfaces of the first frequency-doubling crystal 27 are coated with anti-reflection films for the emerald laser output from the second optical path and its frequency-doubled laser. The two light-transmitting surfaces of 8 are coated with anti-reflection films for the emerald laser output from the second optical path 2, as well as its frequency-doubled and third-doubled lasers. The 756nm laser output through the emerald laser output mirror 26 in the second optical path 2 can achieve 378nm frequency-doubled laser output when the first frequency-doubled crystal 27 in the second optical path 2 is in the optical path and the second frequency-doubled crystal 28 in the second optical path 2 is not in the optical path; when both the first frequency-doubled crystal 27 and the second frequency-doubled crystal 28 in the second optical path 2 are in the optical path, 252nm frequency-doubled laser output can be achieved.

[0047] The focusing lens 30 has a focal length of 100mm, which focuses the yellow laser light passing through the 594nm focusing lens 30 onto the emerald crystal 32 in the third optical path 3 for pumping. The emerald crystal 32 in the third optical path 3 is cut with Brewster angle and has a crystal size of 4×4×15mm. 3 After absorbing 594nm yellow laser light, population inversion occurs. As the pump energy increases, the gain exceeds the loss, thus generating spontaneous emission photons. The emerald resonator adopts a four-mirror ring cavity type. The emerald laser first reflecting mirror 31 and the emerald laser second reflecting mirror 33 in the third optical path 3 are concave mirrors with a radius of curvature of 100mm, and the concave surfaces are coated with a 700-860nm high-reflection film. The angle between the two mirrors is 15~20°. The emerald laser third reflecting mirror 34 in the third optical path 3 is a flat mirror with one side coated with a 700-860nm high-reflection film. The emerald laser output mirror 36 in the second optical path 2 is a flat mirror with one side coated with a 700-860nm partially transparent film. The transmittance is 5~20%; the tuning element 35 in the third optical path 3 uses two birefringent filters (BRF) with thicknesses of 5mm and 10mm respectively. The tunable output of the sapphire laser is achieved by rotating the BRF; the spontaneous emission photons generated by the sapphire crystal 32 in the third optical path 3 form a stable laser oscillation in the four-mirror ring resonant cavity composed of the first sapphire laser mirror 31, the second sapphire laser mirror 33, the third sapphire laser mirror 34, and the output mirror 36 in the third optical path 3, and the 772nm laser is output through the output mirror 36 in the third optical path 3.

[0048] Within the third optical path 3, both the first frequency-doubling crystal 37 and the second frequency-doubling crystal 38 are mounted on a movable platform. These two crystals can be inserted into and removed from the optical path electrically or manually. Both end faces of the first frequency-doubling crystal 37 and the second frequency-doubling crystal 38 within the third optical path 3 are polished. The two light-transmitting surfaces of the first frequency-doubling crystal 37 are coated with anti-reflection films for the emerald laser output from the third optical path and its frequency-doubled laser. The second frequency-doubling crystal within the third optical path 3... The two light-transmitting surfaces of 38 are coated with anti-reflection films for the emerald laser output from the third optical path, as well as its frequency-doubled and fourth-doubled lasers. The 772nm laser output through the emerald laser output mirror 36 in the third optical path 3 can achieve 386nm frequency-doubled laser output when the first frequency-doubled crystal 37 in the third optical path 3 is in the optical path and the second frequency-doubled crystal 38 in the third optical path 3 is not in the optical path; when both the first frequency-doubled crystal 37 and the second frequency-doubled crystal 38 in the third optical path 3 are in the optical path, 193nm frequency-doubled laser output can be achieved.

[0049] Through the first optical path 1, the second optical path 2, and the third optical path 3, the simultaneous output of multiple wavelengths of laser light can be achieved: First optical path 1: 744nm, 372nm, 248nm Second optical path 2: 752nm, 378nm, 252nm Third optical path 3: 772nm, 386nm, 193nm Any combination of wavelengths selected from the first optical path 1, the second optical path 2, and the third optical path 3.

[0050] In the above embodiments, when the combination of self-frequency doubling crystal, emerald crystal and frequency doubling crystal is different, the cutting angle of each crystal will also be different. At the same time, the wavelengths of the fundamental frequency light and frequency-doubled yellow light in the self-frequency doubling crystal, as well as the tunable laser and frequency-doubled laser in the emerald laser, will also be different. The resonant cavity reflector, harmonic plate and yellow light output mirror and the coating of each crystal should also be changed accordingly. The specific wavelengths can be found in the literature, and will not be described in detail here.

[0051] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A multi-wavelength output tunable laser, characterized in that, include: Pump source; The reflection unit includes a first reflector, a second reflector, and a third reflector. The first reflector is positioned in the propagation direction of the pump source optical path and is located at the rear end of the pump source. The second reflector is located in the reflected optical path of the first reflector, and the third reflector is located in the transmitted optical path of the second reflector. The first, second, and third reflectors have different reflectivities. Optical path unit: includes a first optical path unit, a second optical path unit and a third optical path unit, wherein the first optical path unit is disposed on the transmission optical path of the first reflector, the second optical path unit is disposed on the isolated optical path of the second reflector, and the third optical path unit is disposed on the reflection optical path of the third reflector.

2. The multi-wavelength output tunable laser according to claim 1, characterized in that, Along the propagation direction of the optical path, the pump source sequentially includes: a laser diode, a coupling lens group, a half-wave plate, and a self-frequency doubling crystal; the first reflector is located at the rear end of the self-frequency doubling crystal.

3. The multi-wavelength output tunable laser according to claim 1 or 2, characterized in that, The first reflector is at a 45° angle to the propagation direction of the pump source optical path, and the transmittance of the first reflector is 67%.

4. The multi-wavelength output tunable laser according to claim 1, characterized in that, The second reflector forms a 45° angle with the propagation direction of the reflective optical fiber of the first reflector, and the light transmittance of the second reflector is 50%.

5. The multi-wavelength output tunable laser according to claim 1, characterized in that, The propagation direction of the third reflecting mirror is at a 45° angle to the propagation direction of the reflecting optical fiber of the second reflecting mirror, and the third reflecting mirror is a total reflection mirror.

6. The multi-wavelength output tunable laser according to claim 1, characterized in that, Along the propagation direction of the light path, the first optical path unit, the second optical path unit, and the third optical path unit each sequentially include: The system comprises a first emerald laser reflector, an emerald crystal, a second emerald laser reflector, a third emerald laser reflector, and an emerald laser output mirror; the first and second emerald laser reflectors are concave mirrors, and the third emerald laser reflector is a plane mirror. The concave surfaces of the first emerald laser reflector and the second emerald laser reflector are opposite each other, and the first emerald laser reflector is tilted relative to the propagation of transmitted light from the first reflector; the emerald crystal is disposed in the transmission optical path of the first emerald laser reflector, and the third emerald laser reflector is disposed in the emerald crystal; the emerald laser output mirror is disposed in the reflection optical path of the first emerald laser, and the third emerald laser reflector is disposed in the reflection optical path of the second emerald laser reflector. The first emerald laser reflector of the first optical path is disposed in the transmission optical path of the first reflector, the second emerald laser reflector of the second optical path is disposed in the reflection optical path of the second reflector, and the third emerald laser reflector of the third optical path is disposed in the reflection optical path of the third reflector.

7. The multi-wavelength output tunable laser according to claim 6, characterized in that, The first optical path unit, the second optical path unit, and the third optical path unit further include: a focusing lens; The focusing lens of the first optical path unit is disposed between the first emerald laser reflector and the first reflector in the first optical path; The focusing lens of the second optical path unit is disposed between the first emerald laser reflector and the second reflector in the second optical path; The focusing lens of the third optical path unit is positioned between the first emerald laser reflector and the third reflector in the third optical path.

8. The multi-wavelength output tunable laser according to claim 6, characterized in that, The first optical path unit, the second optical path unit, and the third optical path unit further include a frequency multiplication unit.

9. The multi-wavelength output tunable laser according to claim 8, characterized in that, The frequency doubling unit includes a first frequency doubling crystal and a second frequency doubling crystal.

10. The multi-wavelength output tunable laser according to claim 6, characterized in that, The first optical path unit, the second optical path unit, and the third optical path unit all further include a resonant element, which is disposed between the second emerald laser reflector and the third emerald laser reflector.

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