Single-pumping-source end-pumped multi-module laser

Abstract

The embodiment of the utility model provides a single-pump-source end-pumped multi-module laser, and belongs to the technical field of laser. The laser comprises a pumping source used for outputting pumping light; the spectroscope is arranged at the rear end of the pumping source and is used for carrying out light splitting operation on the pumping light so as to obtain a first light path perpendicular to a connecting line of the center of the pumping source and the center of the spectroscope and a second light path collinear with the connecting line of the center of the pumping source and the center of the spectroscope; the first total reflection mirror is arranged on the first light path and used for vertically adjusting the direction of the first light path to obtain a third light path; the first resonant cavity is arranged on the third light path, is located at the rear end of the first total reflection mirror and is used for forming laser oscillation and realizing laser output after the first gain medium absorbs the incident pump light; the first gain medium is arranged in the first resonant cavity; the second resonant cavity is arranged on the second light path and located at the rear end of the spectroscope; and the second gain medium is arranged in the second resonant cavity.

Description

Technical Field

[0001] The utility model relates to the technical field of lasers, in particular to a single-pump source end-face pumped multi-mode laser. Background Art

[0002] As one of the major scientific and technological breakthroughs of the 20th century, laser plays an indispensable role in many fields with its excellent directivity, high brightness and excellent monochromaticity. Whether it is industrial manufacturing, national defense and military, information and communication, medical health, or scientific research, the wide application of laser has greatly promoted the development of these fields.

[0003] The core components of a laser include a laser gain medium, a resonant cavity, and a pump source. The role of the pump source is to provide sufficient pump energy for the laser gain medium. During the operation of the laser, the gain medium absorbs the pump light and converts part of its energy into laser output, while the remaining energy exists in the form of waste heat. On the one hand, most of the waste heat needs to be removed by cooling, and on the other hand, the waste heat that is not removed accumulates in the gain medium.

[0004] However, as the pump power or energy increases, the problem of heat accumulation in the gain medium that cannot be removed in time becomes more serious, which will aggravate the thermal effect, resulting in the laser output power not only failing to increase further, but may even saturate or even decrease. It is worth noting that the pump power at this time is actually far from the maximum power value that the pump source can provide. Therefore, the potential of the pump source has not been fully utilized, and its utilization rate is relatively low, which has become a bottleneck limiting the further increase of the laser output power. Utility Model Content

[0005] The purpose of the embodiment of the utility model is to provide a single-pump source end-pumped multi-mode laser, which can increase the power of the output laser.

[0006] In order to achieve the above-mentioned object, the embodiment of the utility model provides a single-pump source end-pumped multi-mode laser, comprising:

[0007] A pump source, used for outputting pump light;

[0008] A spectroscope, disposed at the rear end of the pump source, for performing a spectroscopic operation on the pump light to obtain a first optical path perpendicular to a line connecting the center of the pump source and the center of the spectroscope and a second optical path collinear with a line connecting the center of the pump source and the center of the spectroscope;

[0009] a first total reflection mirror, disposed on the first light path, and used for vertically adjusting the direction of the first light path to obtain a third light path;

[0010] A first resonant cavity is arranged on the third optical path and is located at the rear end of the first total reflection mirror, and is used for the first gain medium to form laser oscillation and realize laser output after absorbing the incident pump light;

[0011] A first gain medium is disposed in the first resonant cavity;

[0012] A second resonant cavity is arranged on the second optical path and located at the rear end of the beam splitter, and is used for the second gain medium to form laser oscillation and realize laser output after absorbing the incident pump light;

[0013] A second gain medium is disposed in the second resonant cavity;

[0014] a second total reflection mirror, arranged on the second optical path and located at the rear end of the second resonant cavity, for transmitting the pump light not absorbed by the second gain medium and reflecting the laser light generated by the second resonant cavity, and adjusting the propagation direction of the laser light generated by the second resonant cavity to obtain a fourth optical path;

[0015] The tail mirror is arranged at the convergence point of the third optical path and the fourth optical path, and is used to reflect the pump light not absorbed by the first gain medium, transmit the laser generated by the first resonant cavity, and reflect the laser incident from the fourth optical path.

[0016] Optionally, the laser includes a collimator, which is disposed between the pump source and the beam splitter and is used to convert the pump light into a beam of parallel light.

[0017] Optionally, a surface of the collimator mirror close to the pump source is a plane, and a surface of the collimator mirror close to the beam splitter is a convex surface.

[0018] Optionally, the laser comprises:

[0019] A first focusing mirror, disposed between the first total reflection mirror and the first resonant cavity, for focusing the third light path;

[0020] The second focusing mirror is arranged between the beam splitter and the second resonant cavity, and is used for focusing the second light path.

[0021] Optionally, the first resonant cavity comprises:

[0022] A third total reflection mirror is arranged at the rear end of the first total reflection mirror, and an anti-reflection film of the wavelength band where the pump light is located and a reflection film of the wavelength band where the laser is generated are arranged on the third total reflection mirror, and the first gain medium is arranged at the rear end of the third total reflection mirror;

[0023] The first output mirror is arranged at the rear end of the first gain medium and is used for partially transmitting the output light, wherein the output light includes the pump light and laser.

[0024] Optionally, the second resonant cavity comprises:

[0025] A fourth total reflection mirror is arranged at the rear end of the beam splitter, and an anti-reflection film of the wavelength band where the pump light is located and a reflection film of the wavelength band where the laser is generated are arranged on the fourth total reflection mirror, and the second gain medium is arranged at the rear end of the fourth total reflection mirror;

[0026] The second output mirror is arranged at the rear end of the second gain medium and is used for partially transmitting the output light.

[0027] Optionally, a wavelength of the pump light output by the pump source includes at least one of 450 nm, 790 nm, 808 nm, 880 nm, 940 nm, 970 nm, 1060 nm, 1150 nm, 1300 nm, 1950 nm, and 2800 nm.

[0028] Optionally, the first resonant cavity includes a first output mirror, the second resonant cavity includes a second output mirror, the first output mirror and the second output mirror are used to partially transmit the output light, and the transmittance of the first output mirror and the second output mirror in the wavelength band where the laser is located is 0.1% to 40%.

[0029] Optionally, the transmittance of the beam splitter in the wavelength band where the pump light is located is 50%, and the reflectivity is 50%.

[0030] Through the above technical solution, the embodiment of the utility model provides a single-pump source end-pumped multi-mode laser, which performs a splitting operation on the pump light, then uses two resonant cavities with built-in gain media, and finally combines the lasers output by the two resonant cavities to increase the power of the output laser. Compared with the prior art, since the laser adopts a method of resonating separately after splitting, it overcomes the technical defects of low output laser power and poor power stability of a single gain medium in the prior art, and increases the power and stability of the output laser.

[0031] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the embodiments of the present utility model and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present utility model, but do not constitute a limitation on the embodiments of the present utility model. In the accompanying drawings:

[0033] Figure 1 The optical path diagram of a single-pump source end-pumped multi-mode laser according to an embodiment of the utility model.

[0034] Description of Reference Numerals

[0035] 1. Pump source 2. Spectroscope

[0036] 3. The first total reflection mirror 4. The first resonant cavity

[0037] 5. First gain medium 6. Second resonant cavity

[0038] 7. Second gain medium 8. Second total reflection mirror

[0039] 9. Tail mirror 10. Collimating mirror

[0040] 11. First focusing mirror 12. Second focusing mirror

[0041] 13. The third total reflection mirror 14. The first output mirror

[0042] 15. Fourth total reflection mirror 16. Second output mirror DETAILED DESCRIPTION

[0043] The specific implementation of the embodiment of the utility model is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the utility model, and is not used to limit the embodiment of the utility model.

[0044] like Figure 1 The figure shows an optical path diagram of a single pump source end-pumped multi-mode laser according to an embodiment of the present utility model. Figure 1In the embodiment, the laser may include a pump source 1, a spectroscope 2, a first total reflection mirror 3, a first resonant cavity 4, a first gain medium 5, a second resonant cavity 6, a second gain medium 7, a second total reflection mirror 8, and a tail mirror 9. The pump source 1 may be used to output pump light. The spectroscope 2 may be disposed at the rear end of the pump source, and is used to perform a spectroscopic operation on the pump light to obtain a first optical path perpendicular to the line connecting the center of the pump source 1 and the center of the spectroscope 2, and a second optical path collinear with the line connecting the center of the pump source 1 and the center of the spectroscope 2. The first total reflection mirror 3 may be disposed on the first optical path, and is used to vertically adjust the direction of the first optical path to obtain a third optical path. The first resonant cavity 4 is disposed on the third optical path, and is located at the rear end of the first total reflection mirror 3, and is used for the first gain medium 5 to absorb the pump light to form laser oscillation and realize laser output. The first gain medium 5 may be disposed in the first resonant cavity 4. The second resonant cavity 6 can be arranged on the second optical path and located at the rear end of the spectroscope 2, and is used for the second gain medium 7 to absorb the pump light to form laser oscillation and realize laser output. The second gain medium 7 can be arranged in the second resonant cavity. The second total reflection mirror 8 can be arranged on the second optical path and located at the rear end of the second resonant cavity 6, and is used to transmit the pump light not absorbed by the second gain medium 7, and reflect the laser generated by the second resonant cavity, and adjust the propagation direction of the laser generated by the second resonant cavity to obtain the fourth optical path. The tail mirror 9 can be arranged at the convergence point of the third optical path and the fourth optical path, and is used to reflect the pump light not absorbed by the first gain medium 5, and transmit the laser generated by the first resonant cavity, and reflect the laser incident on the fourth optical path. Among them, since the spectroscope 2 is used for splitting operation, in order to ensure the stability of the output laser, the power of the first optical path and the second optical path after splitting should be as equal as possible. Therefore, in an example of the utility model, the spectroscope 2 can use a lens with a transmittance of 50% and a reflectivity of 50% in the band where the pump light is located.

[0045] In one embodiment of the utility model, in order to improve the utilization rate of the pump source 1, the laser may further include a collimator 10. The collimator 10 may be disposed between the pump source 1 and the beam splitter 2 to convert the pump light into a beam of parallel light. The specific structure of the collimator 10 may be in various forms known to those skilled in the art. In one example of the utility model, the collimator 10 may be a plano-convex lens, which may include a convex surface and a flat surface. The flat surface may be disposed at one end close to the pump source 1, and the convex surface may be disposed at one end close to the beam splitter 2.

[0046] Further, considering that the collimator 10 adjusts the light beam into a parallel light column with a larger radius, in order to ensure the efficiency of the resonant cavity to generate laser, in this example, the laser may also include a first focusing mirror 11 and a second focusing mirror 12. The first focusing mirror 11 may be arranged between the first total reflection mirror 3 and the first resonant cavity 4 to focus the third light path. The second focusing mirror 12 may be arranged between the beam splitter 2 and the second resonant cavity 6 to focus the second light path. The specific structures of the first focusing mirror 11 and the second focusing mirror 12 may be in various forms known to those skilled in the art. In one example of the utility model, the first focusing mirror 11 may include a plane and a convex surface. The convex surface may be arranged at one end close to the first total reflection mirror 3, and the plane may be arranged at one end close to the first resonant cavity 4. Similarly, the second focusing mirror 12 may include a plane and a convex surface. The convex surface may be arranged at one end close to the beam splitter 2, and the plane may be arranged at one end close to the second resonant cavity 6.

[0047] In this embodiment, the specific structure of the first resonant cavity 4 can be in various forms known to those skilled in the art. In one example of the present utility model, the first resonant cavity 4 can include a third total reflection mirror 13 and a first output mirror 14. The third total reflection mirror 13 can be arranged at the rear end of the first total reflection mirror 3, and the third total reflection mirror 13 can be provided with (applied or electroplated) an anti-reflection film in the band where the pump light is located and a reflection film in the band where the laser is generated, so as to transmit the pump light and reflect the generated laser at the same time. The first gain medium 5 can be arranged at the rear end of the third total reflection mirror 13. The first output mirror 14 can be arranged at the rear end of the first gain medium 5 for partially transmitting the output light. The selection of the structure and model of the first output mirror 14 can be in various forms known to those skilled in the art. In one example of the present utility model, the first output mirror 14 can be a plane lens with a transmittance of 0.1% to 40% in the band where the output laser is located.

[0048] In this embodiment, the specific structure of the second resonant cavity 6 can be in various forms known to those skilled in the art. In one example of the present utility model, the second resonant cavity 6 can include a fourth total reflection mirror 15 and a second output mirror 16. The fourth total reflection mirror 15 can be arranged at the rear end of the beam splitter 2, and the fourth total reflection mirror 15 can be provided (applied or electroplated) with an anti-reflection film in the band where the pump light is located and a reflection film in the band where the laser is generated, so as to transmit the pump light and reflect the generated laser at the same time. The second gain medium 7 can be arranged at the rear end of the fourth total reflection mirror 15. The second output mirror 16 can be arranged at the rear end of the second gain medium 7 for partially transmitting the output light. The selection of the structure and model of the second output mirror 16 can be in various forms known to those skilled in the art. In one example of the present utility model, the second output mirror 16 can be a plane lens with a transmittance of 0.1% to 40% in the band where the output laser is located. The specific materials of the first gain medium 5 and the second gain medium 7 can be various materials known to those skilled in the art, including but not limited to rare earth doped laser crystals, rare earth doped transparent ceramics, rare earth doped optical fibers, etc. In this example, the first gain medium 5 and the second gain medium 7 can preferably be rare earth doped laser crystals.

[0049] In addition, in this embodiment, the type and specific model of the pump source 1 can be various types known to those skilled in the art. In one example of the present invention, when selecting the model of the pump source 1, a pump source device having an output pump light wavelength of at least one of 450nm, 790nm, 808nm, 880nm, 940nm, 970nm, 1060nm, 1150nm, 1300nm, 1950nm, and 2800nm ​​can be selected.

[0050] Through the above technical solution, the embodiment of the utility model provides a single-pump source end-pumped multi-mode laser, which performs a splitting operation on the pump light, then uses two resonant cavities with built-in gain media, and finally combines the lasers output by the two resonant cavities to improve the power and stability of the output laser. Compared with the prior art, since the laser adopts a method of resonating separately after splitting, it overcomes the technical defects of low laser power and poor stability of a single gain medium output in the prior art, and improves the power and stability of the output laser.

[0051] In the description of the present utility model, it is necessary to understand that the terms "first", "second", "third" and "fourth" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", "third" and "fourth" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "multi-module" is two or more modules, unless otherwise clearly and specifically defined.

[0052] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0053] The above has expressed the implementation of the utility model, and its description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A single pump source end-pumped multi-mode laser, characterized in that: The laser comprises: A pump source, used for outputting pump light; A spectroscope, disposed at the rear end of the pump source, for performing a spectroscopic operation on the pump light to obtain a first optical path perpendicular to a line connecting the center of the pump source and the center of the spectroscope and a second optical path collinear with a line connecting the center of the pump source and the center of the spectroscope; a first total reflection mirror, disposed on the first light path, and used for vertically adjusting the direction of the first light path to obtain a third light path; A first resonant cavity is arranged on the third optical path and is located at the rear end of the first total reflection mirror, and is used for the first gain medium to form laser oscillation and realize laser output after absorbing the incident pump light; A first gain medium is disposed in the first resonant cavity; A second resonant cavity is arranged on the second optical path and located at the rear end of the beam splitter, and is used for the second gain medium to form laser oscillation and realize laser output after absorbing the incident pump light; A second gain medium is disposed in the second resonant cavity; a second total reflection mirror, arranged on the second optical path and located at the rear end of the second resonant cavity, for transmitting the pump light not absorbed by the second gain medium and reflecting the laser light generated by the second resonant cavity, and adjusting the propagation direction of the laser light generated by the second resonant cavity to obtain a fourth optical path; The tail mirror is arranged at the convergence point of the third optical path and the fourth optical path, and is used to reflect the pump light not absorbed by the first gain medium, transmit the laser generated by the first resonant cavity, and reflect the laser incident from the fourth optical path.

2. The laser according to claim 1, characterized in that The laser comprises a collimator, which is arranged between the pump source and the beam splitter and is used for converting the pump light into a beam of parallel light.

3. The laser according to claim 2, characterized in that A surface of the collimator mirror close to the pump source is a plane, and a surface of the collimator mirror close to the beam splitter is a convex surface.

4. The laser according to claim 3, characterized in that The laser comprises: A first focusing mirror, disposed between the first total reflection mirror and the first resonant cavity, for focusing the third light path; The second focusing mirror is arranged between the beam splitter and the second resonant cavity, and is used for focusing the second light path.

5. The laser according to claim 1, characterized in that The first resonant cavity comprises: A third total reflection mirror is arranged at the rear end of the first total reflection mirror, and an anti-reflection film of the wavelength band where the pump light is located and a reflection film of the wavelength band where the laser is generated are arranged on the third total reflection mirror, and the first gain medium is arranged at the rear end of the third total reflection mirror; The first output mirror is arranged at the rear end of the first gain medium and is used for partially transmitting the output light, wherein the output light includes the pump light and laser.

6. The laser according to claim 1, characterized in that The second resonant cavity comprises: A fourth total reflection mirror is arranged at the rear end of the beam splitter, and an anti-reflection film of the wavelength band where the pump light is located and a reflection film of the wavelength band where the laser is generated are arranged on the fourth total reflection mirror, and the second gain medium is arranged at the rear end of the fourth total reflection mirror; The second output mirror is arranged at the rear end of the second gain medium and is used for partially transmitting the output light.

7. The laser according to claim 1, characterized in that The wavelength of the pump light output by the pump source includes at least one of 450nm, 790nm, 808nm, 880nm, 940nm, 970nm, 1060nm, 1150nm, 1300nm, 1950nm, and 2800nm.

8. The laser according to claim 1, characterized in that The first resonant cavity includes a first output mirror, and the second resonant cavity includes a second output mirror. The first output mirror and the second output mirror are used to partially transmit the output light, and the transmittance of the first output mirror and the second output mirror in the wavelength band where the laser is located is 0.1% to 40%.

9. The laser according to claim 1, characterized in that The transmittance of the beam splitter in the wavelength band where the pump light is located is 50%, and the reflectivity is 50%.

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