Mixing cavity laser device

Abstract

The invention discloses a mixing cavity laser device which comprises a solid laser medium, a pumping source, a first cavity mirror, a second cavity mirror, a folding mirror and a scraper mirror. The pumping source is used for providing pumping light for the solid laser medium; the solid laser medium is used for generating laser gain, the laser fast axis direction of the solid laser medium is the Y-axis direction, and the laser slow axis direction of the solid laser medium is the Z-axis direction; the first cavity mirror and the second cavity mirror form an optical resonant cavity for oscillating laser; the first cavity mirror and the second cavity mirror form an unstable cavity structure in the laser fast axis direction and form a stable cavity structure in the laser slow axis direction. The folding mirror is arranged between the solid laser medium and the second cavity mirror, the folding mirror is used for folding the cavity length in the non-stable cavity direction, and the folding mirror is used for increasing the divergence angle of a laser beam and increasing the volume of a fundamental mode in the stable cavity direction; the scraper mirror is arranged in the unstable cavity structure and is used for adjusting the laser intensity and the laser direction in the unstable cavity structure; and a laser beam generated by the laser device is output through the second cavity mirror or the scraper mirror.

Description

Technical Field

[0001] The present invention relates to the field of solid laser technology, and more specifically, to a hybrid cavity laser device. Background Art

[0002] Slab lasers use large-aperture laser materials as gain media and can produce high-power laser output. They are widely used in material processing, medical treatment, and national defense. The application of slab lasers has high requirements for the output power of the laser and the beam quality. However, the slab laser with a stable cavity structure has limited output power and poor beam quality due to the limitation of the fundamental mode size by its stable optical cavity design. Slab lasers with an unstable cavity structure can increase the laser mode radius to improve the beam quality. However, the unstable cavity structure introduces the problem of aperture differences in two directions, affecting the symmetry of the beam. The slab laser with an unstable cavity and a stable cavity hybrid cavity structure combines the advantages of a stable cavity and an unstable cavity, and can effectively compensate for the difference in beam aperture in different directions, thereby improving the beam quality and enhancing the overall performance and stability of the laser; however, due to the limitation of the mode volume, it is difficult to have a large fundamental mode gain volume in the stable cavity direction, thereby limiting the high-power, high-beam-quality laser output in the stable cavity direction. Summary of the invention

[0003] The present invention provides a hybrid cavity laser device to solve at least one of the problems existing in the prior art.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention provides a hybrid cavity laser device, which includes a solid laser medium, a pump source, a first cavity mirror, a second cavity mirror, a folding mirror and a scraper mirror;

[0006] The pump source is used to provide pump light for the solid laser medium;

[0007] The solid laser medium is used to generate laser gain, the width direction of the solid laser medium is the Y-axis direction, which is the laser fast axis direction, and the thickness direction of the solid laser medium is the Z-axis direction, which is the laser slow axis direction;

[0008] The first cavity mirror and the second cavity mirror are respectively arranged on both sides of the end face of the solid laser medium, and the first cavity mirror and the second cavity mirror constitute an optical resonant cavity for oscillating laser;

[0009] The first cavity mirror and the second cavity mirror form an unstable cavity structure in the laser fast axis direction, and the first cavity mirror and the second cavity mirror form a stable cavity structure in the laser slow axis direction;

[0010] The folding mirror is arranged between the solid laser medium and the second cavity mirror, and the folding mirror is used to fold the cavity length in the unstable cavity structure, and is used to increase the divergence angle of the laser beam in the stable cavity structure;

[0011] The scraper mirror is arranged in the unstable cavity structure and is used to adjust the laser intensity and laser direction in the unstable cavity structure;

[0012] The laser beam generated by the laser device is output through the second cavity mirror or the scraper mirror.

[0013] Optionally, the folding mirror is a plane folding mirror in the unstable cavity structure;

[0014] The folding mirror is a concave folding mirror or a convex folding mirror in the stable cavity structure.

[0015] Optionally, the number of the folding mirrors is one or more.

[0016] Optionally, the first cavity mirror is a first concave mirror in the unstable cavity structure, and the second cavity mirror is a second concave mirror or a convex mirror in the unstable cavity structure;

[0017] The first cavity mirror is a first concave mirror in the stable cavity structure, and the second cavity mirror is a plane mirror in the stable cavity structure.

[0018] Optionally, the unstable cavity structure is a positive branch unstable cavity structure or a negative branch unstable cavity structure.

[0019] Optionally, the unstable cavity structure is a coaxial unstable cavity structure or an off-axis unstable cavity structure.

[0020] Optionally, the solid laser medium is a solid laser medium whose cross-section in the light transmission direction is rectangular, trapezoidal or elliptical.

[0021] Optionally, an angle is set between the scraper mirror and the optical axis of the optical resonant cavity, and the scraper mirror is a perforated scraper mirror or a solid scraper mirror.

[0022] Optionally, the scraper mirror is a hole-perforating scraper mirror, and the focal points of the first cavity mirror and the second cavity mirror coincide with the parallel light center axis of the hole-perforating scraper mirror;

[0023] The scraper mirror is a solid scraper mirror, and the solid scraper mirror is placed away from one side of the solid laser medium.

[0024] Optionally, a surface of the scraper mirror close to the folding mirror is coated with a high-reflective film for laser, so as to reflect the output laser beam.

[0025] The beneficial effects of the present invention are as follows:

[0026] The hybrid cavity laser device provided by the present invention adds a folding mirror in the optical resonant cavity, changes the propagation direction of the laser beam through the folding mirror, expands the light beam in the stable cavity direction, increases the divergence angle of the laser beam, increases the fundamental mode volume, reduces the number of starting transverse modes, and increases the fundamental mode volume of the stable cavity structure while maintaining the fundamental mode volume of the unstable cavity structure, thereby having a laser beam with high power and high beam quality in both the unstable cavity and stable cavity directions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0028] Figure 1 A schematic diagram showing a hybrid cavity laser device of the present invention;

[0029] Figure 2 A schematic diagram showing a top view of a hybrid cavity slab laser device of the present invention in a coaxial unstable cavity structure;

[0030] Figure 3 A schematic diagram showing a top view of a hybrid cavity slab laser device of the present invention in an off-axis unstable cavity structure;

[0031] Figure 4 A schematic diagram showing a hybrid cavity slab laser device of the present invention in the front view direction of the cavity stabilization structure;

[0032] Figure 5 A schematic diagram showing the front view direction of the hybrid cavity slab laser device of the present invention when the cavity stabilizing structure does not use a folding mirror. DETAILED DESCRIPTION

[0033] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0034] The present invention provides a hybrid cavity laser device. Figure 1 is a schematic diagram of a hybrid cavity laser device, the laser device comprising a solid laser medium, a pump source, a first cavity mirror, a second cavity mirror, a folding mirror and a scraper mirror;

[0035] The pump source is used to provide pump light for the solid laser medium. The pump source is arranged on at least one end face, large face or side face of the plate solid laser medium. The pump source can be an LD stack array. The pump light is coupled into the solid laser medium through at least one end face, large face or side face of the solid laser medium after beam shaping.

[0036] The solid laser medium is used to generate laser gain, and the cross section of the solid laser medium in the light transmission direction can be a solid laser medium in a rectangular, trapezoidal or elliptical shape;

[0037] In unstable and stable hybrid cavity laser devices, a solid laser medium with an irregular cross section in the light transmission direction such as a rectangle, trapezoid, or ellipse is selected to optimize the propagation characteristics and mode control of the laser beam in the resonant cavity;

[0038] Laser media with rectangular, trapezoidal or elliptical cross-sections in the through direction can achieve better divergence of the laser beam on the unstable cavity structure by controlling the geometric distribution of the light beam, thereby meeting the intracavity mode requirements. Unstable cavity structures and stable cavity structures have different requirements for laser modes. Selecting laser media with irregular shapes can adjust the mode characteristics in the stable cavity direction while maintaining the appropriate fundamental mode volume on the unstable cavity structure. Selecting laser media with irregular shapes can better cooperate with the folding mirror design, optimize the spatial distribution and propagation mode of the laser beam in the cavity, thereby improving the efficiency and stability of laser output. Laser media with irregular cross-sections in the through direction can also effectively avoid the mode competition problem that may be caused by circular media. By accurately designing the shape of the medium, the laser mode structure is adjusted, the quality of the output beam is controlled, unnecessary high-order modes are avoided, and the performance of the laser is guaranteed. Selecting laser media with irregular cross-sections in the through direction such as rectangles, trapezoids, ellipses, etc. can better meet the requirements of unstable and stable cavities, optimize the divergence, propagation and mode characteristics of the laser beam, thereby improving the overall efficiency and stability of the laser device.

[0039] The first cavity mirror and the second cavity mirror are respectively arranged on both sides of the end face of the solid laser medium, and the first cavity mirror and the second cavity mirror constitute an optical resonant cavity for oscillating laser;

[0040] The first cavity mirror and the second cavity mirror form an unstable cavity structure in the direction of the laser fast axis, and the first cavity mirror and the second cavity mirror form a stable cavity structure in the direction of the laser slow axis. The unstable cavity structure is a positive branch unstable cavity structure or a negative branch unstable cavity structure; the unstable cavity structure can also be a coaxial unstable cavity structure or an off-axis unstable cavity structure;

[0041] In the unstable cavity structure, the first cavity mirror is a first concave mirror, and the second cavity mirror is a second concave mirror or a convex mirror; in the stable cavity structure, the first cavity mirror is a first concave mirror, and the second cavity mirror is a plane mirror;

[0042] The folding mirror is arranged between the solid laser medium and the second cavity mirror. In the unstable cavity structure, the folding mirror is a plane folding mirror, which is used to fold the cavity length; in the stable cavity structure, the folding mirror is a concave folding mirror or a convex folding mirror, which is used to increase the divergence angle of the laser beam, increase the fundamental mode volume, and improve the beam quality; the number of folding mirrors in the laser device can be one or more;

[0043] The scraper mirror is arranged between the second cavity mirror and the folding mirror, and is used to adjust the laser intensity and laser direction in the unstable cavity structure. An angle is set between the scraper mirror and the optical axis of the optical resonant cavity, and the laser intensity and laser direction are adjusted by adjusting the angle and position between the scraper mirror and the optical resonant cavity. The scraper mirror is an open-hole scraper mirror or a solid scraper mirror. When the scraper mirror is an open-hole scraper mirror, the focal points of the first cavity mirror and the second cavity mirror coincide with the parallel light center axis of the open-hole scraper mirror. When the scraper mirror is a solid scraper mirror, the solid scraper mirror is placed away from the solid laser medium.

[0044] The surface of the open-hole scraper mirror close to the folding mirror (except the open hole) is coated with a high-reflective film for laser, which is used to reflect the output laser beam; the surface of the solid scraper mirror close to the folding mirror is coated with a high-reflective film for laser, which is used to reflect the output laser beam; the surface of the first cavity mirror close to the slab laser medium is coated with a high-reflective film for laser, and the surface of the second cavity mirror close to the folding mirror is coated with a partial anti-reflective film for laser, wherein the reflectivity of the high-reflective film for laser is greater than 99%.

[0045] The laser beam generated by the laser device is output through the second cavity mirror or the scraper mirror.

[0046] The hybrid cavity laser device provided by the present invention increases the volume of the fundamental mode in the stable cavity direction while maintaining the volume of the unstable cavity fundamental mode by adding a folding mirror structure in the hybrid cavity and the laser device, thereby improving the beam quality. The propagation direction of the laser beam is changed by the folding mirror so that it expands in the stable cavity direction, thereby increasing the volume of the fundamental mode. The larger fundamental mode volume can reduce the number of starting transverse modes, thereby producing a laser beam with high output power and high beam quality in both the stable cavity and unstable cavity directions.

[0047] In a specific embodiment, the solid laser medium is a slab laser medium. Figure 2 Schematic diagram of a hybrid cavity slab laser device in a top view direction of a coaxial unstable cavity structure, the device includes a slab laser medium 1, a pump source (the pump source is not in Figure 2 ), an optical resonant cavity composed of a first cavity mirror and a second cavity mirror, and a folding mirror and a scraper mirror located in the optical resonant cavity, wherein in the unstable cavity structure, the first cavity mirror is a first concave mirror 2, the second cavity mirror is a second concave mirror 3, the folding mirror is a plane folding mirror 4, and the scraper mirror is an open hole scraper mirror 5, Figure 2 The direction of the middle arrow is the laser output direction, and the X-axis direction is the light transmission direction.

[0048] The active ions in the slab laser medium 1 include at least one of Nd, Yb, Ti, Pr, Cr, Tm or Ho, and / or the matrix material of the slab laser medium 1 includes at least one of crystal, glass and ceramic. Figure 2, the X-axis direction is the length direction of the slab laser medium, the Y-axis direction is the width direction of the slab laser medium, and the Z-axis direction is the thickness direction of the slab laser medium. The length of the slab laser medium>width≥thickness, the width direction of the slab laser medium is the laser fast axis direction, and the thickness direction of the slab laser medium is the laser slow axis direction; the slab laser medium has six faces, the large face usually refers to the two faces orthogonal to the thickness direction, the large face has the largest area, and can be used to install cooling devices, and the pump source is usually pumped from the large face; the side face usually refers to the two faces orthogonal to the width direction, and can also be pumped from the side face; the end face usually refers to the two faces perpendicular to the light transmission direction, which are the faces where the laser is output from the slab laser medium 1, and can also be pumped from the end face. The cross section of the light transmission direction of the solid laser medium can also be an irregular polygon such as a rectangle or an ellipse.

[0049] The pump source provides pump light for the slab laser medium 1 and is arranged on at least one end face, side face or large face of the slab laser medium 1. The pump source may be a stacked LD array. The pump light is coupled into the slab laser medium 1 through at least one end face, side face or large face of the slab laser medium 1 after beam shaping.

[0050] The resonant cavity includes a first concave mirror 2 and a second concave mirror 3 respectively arranged on both sides of the end face of the slab laser medium 1, and a plane folding mirror 4 arranged between the slab laser medium 1 and the second concave mirror 3, wherein the first concave mirror 2 and the second concave mirror 3 constitute an optical resonant cavity for oscillating laser. The first concave mirror 2 and the second concave mirror 3 constitute an unstable cavity structure in the direction of the laser fast axis, and constitute a stable cavity structure in the direction of the laser slow axis; the unstable cavity structure constituted in the direction of the laser fast axis can be a positive branch unstable cavity structure or a negative branch unstable cavity structure. In the unstable cavity structure, the second cavity mirror can also be a convex mirror. In the resonant cavity, the unstable cavity structure constituted in the direction of the laser fast axis can also be a coaxial unstable cavity structure or an off-axis unstable cavity structure.

[0051] The plane mirror 4 is used to fold the cavity length in the unstable cavity structure, and is used to increase the divergence angle of the laser beam, increase the fundamental mode volume, and improve the beam quality in the stable cavity structure. The number of the plane folding mirrors 4 can be one or more.

[0052] The scraper mirror arranged between the second concave mirror 3 and the plane folding mirror 4 is used to act as an aperture inside the resonant cavity and reflect the output laser beam to the outside of the resonant cavity. An angle is set between the scraper mirror and the optical axis of the resonant cavity. According to the requirements of the laser beam emission, the angular position and reflectivity of the scraper mirror are adjusted to control the intensity and direction of the output laser.

[0053] Figure 2The scraper mirror in the structure is a perforated scraper mirror 5, and the position of the laser beam in the optical path is controlled by the light hole of the perforated scraper mirror 5, thereby controlling the light aperture of the laser. In the round trip of the optical path of the unstable cavity structure cavity, in the direction of the laser fast axis, the parallel collimated laser emitted from the slab laser medium 1 is reflected by the slab laser medium 1 and the plane folding mirror 4, and part of the laser passes through the light hole of the perforated scraper mirror 5 to form resonance. This part of the laser passes through the reflection of the second concave mirror 3, and then passes through the common focus with the first concave mirror 2, and then coincides with the central axis of the parallel light passing through the scraper mirror, that is, the central axis perpendicular to the width direction of the slab medium. When it reaches the first concave mirror 2, it can be diverged to the full aperture of the light spot, that is, it reaches the same aperture as the end face of the slab laser medium 1. Since an angle is set between the perforated scraper mirror 5 and the optical axis of the resonant cavity, the laser reflected back from the first concave mirror 2 becomes a parallel collimated laser again, and the generated laser can be output through the perforated scraper 5 and the second concave mirror 3. In the coaxial unstable cavity structure, a high-reflective film for laser is coated on one side of the perforated scraper mirror 5 close to the plane folding mirror 4 (except for the light-through hole), and part of the laser beam passes through the light-through hole of the perforated scraper mirror 5 to reach the second concave mirror 3, and the laser beam that does not pass through the light-through hole is reflected and outputted through the perforated scraper mirror 5.

[0054] The focal points of the first concave mirror 2 and the second concave mirror 3 coincide with the central axis of the parallel light passing through the aperture scraper mirror 5, that is, the central axis perpendicular to the width direction of the slab laser medium 1. Therefore, the laser passing through the light hole of the aperture scraper mirror 5 is symmetrical about the laser fast and slow axis of the slab laser medium 1, and the laser reflected by the aperture scraper mirror 5 is also symmetrical about the laser fast and slow axis of the slab laser medium 1.

[0055] Figure 3 This is a schematic diagram of the off-axis unstable cavity structure of the hybrid cavity laser device in the top view direction. In the off-axis unstable cavity structure, the laser beam does not propagate along the central axis, but along a path deviated from the cavity axis. Figure 3 The direction of the middle arrow is the laser output direction. The similarities between the off-axis unstable cavity structure and the above-mentioned coaxial unstable cavity structure are not repeated here.

[0056] The off-axis unstable cavity structure includes a slab laser medium 1, a first concave mirror 2, a second concave mirror 3, a plane folding mirror 4, a scraper mirror and a pump source (the pump source is Figure 3(not shown), wherein the scraper mirror is a solid scraper mirror 6, that is, a scraper mirror without openings. The placement of the solid scraper mirror 6 is different from that of the scraper mirror 5 with openings. The solid scraper mirror 6 needs to be placed away from the width direction of the slab laser medium 1, and the positions of the first concave mirror 2 and the second concave mirror 3 are adjusted accordingly, so that the overlapping focus of the first concave mirror 2 and the second concave mirror 3 is on the parallel light center axis of the solid scraper mirror 6, so as to achieve the effect that the parallel collimated laser passing through the solid scraper mirror 6 reaches the first concave mirror 2 after being reflected by the second concave mirror 3 and the laser beam diverges to the same caliber as the end face of the slab laser medium 1.

[0057] The surface of the second concave mirror 3 close to the plane folding mirror 4 is coated with a partial anti-reflection film of the laser, and the surface of the solid scraper mirror 6 close to the plane folding mirror 4 is coated with a high-reflection film of the laser, wherein the reflectivity of the high-reflection film of the laser is greater than 99%, and the transmittance and reflectivity of the partial anti-reflection film of the laser are set according to actual conditions.

[0058] The solid scraper mirror 6 is placed on one side away from the width direction of the slab laser medium 1 to form a laser path. Part of the laser reaches the second concave mirror 3 and is transmitted through the second concave mirror 3 to output the laser beam. The other part of the laser that does not pass through the laser path is reflected and output through the solid scraper mirror 6.

[0059] By adjusting the angular position and reflectivity of the solid scraper mirror 6, the intensity and direction of the output laser beam are controlled, and the positions of the first concave mirror 2 and the second concave mirror 3 are adjusted so that the divergence angle of the laser beam reaching the first concave mirror 2 after being reflected by the second concave mirror 3 is the same as the end face aperture of the slab laser medium 1.

[0060] In the direction of the laser slow axis, Figure 4 The schematic diagram of the front view direction of the cavity stabilizing structure in the hybrid cavity slab laser device includes a slab laser medium 1, a first cavity mirror, a second cavity mirror, a folding mirror and a pump source (the pump source is at Figure 4 (not shown in the figure), wherein the first cavity mirror is a first concave mirror 2, the second cavity mirror is a plane mirror 7, the folding mirror is a convex folding mirror 8, and the folding mirror can also be a concave folding mirror. The first concave mirror 2 and the plane mirror 7 constitute an optical resonant cavity, and the laser resonates stably between the first concave mirror 2 and the plane mirror 7.

[0061] Taking the convex folding mirror 8 as an example, during the laser oscillation process, the divergence angle of the laser beam and the spot area of ​​the laser beam in the cavity are changed by adjusting the angle and position of the convex folding mirror 8. By increasing the divergence angle of the laser beam, the diameter of the laser beam becomes larger in the oscillation cavity, so that the spot area of ​​the laser beam in the cavity becomes larger, thereby increasing the fundamental mode volume. The laser emitted by the slab laser medium 1 is refracted through the curved surface of the convex folding mirror 8, thereby changing the propagation direction of the laser. After being refracted to the plane mirror 7, the laser is reflected by the plane mirror 7. After being refracted by the convex folding mirror 8 and transmitted by the slab laser medium 1, the spot diameter is increased when it reaches the first concave mirror 2, so that the spot area returning to the first concave mirror 2 is larger than the spot area output from the end face of the slab laser medium 1, that is, the spot of the laser beam becomes wider during the propagation process, and the light field of the fundamental mode volume can cover a wider area, which is conducive to the uniformity of the light field and the stability of the mode.

[0062] Figure 5 The schematic diagram of the front view direction of the stabilizing cavity structure in the hybrid cavity slab laser device without the folding mirror is shown. Only the convex folding mirror 8 in the stabilizing cavity structure is replaced by a plane reflector 9. During the laser oscillation process, the angle and position of the plane reflector 9 are adjusted. After the laser emitted from the end face of the slab laser medium 1 is reflected by the plane reflector 9, it reaches the plane mirror 7 and then reflects the laser by the plane mirror 7. After being reflected by the plane reflector 9 again, the spot area reaching the first concave mirror 2 does not increase significantly. Therefore, adjusting the angle and position of the plane reflector 9 cannot significantly increase the divergence angle of the laser beam and the spot area of ​​the laser beam in the cavity, and thus cannot significantly increase the volume of the fundamental mode. Therefore, the convex folding mirror 8 changes the divergence angle of the laser beam through its optical characteristics, so that the laser forms a larger spot in the cavity, thereby increasing the volume of the fundamental mode. A larger spot area can make the fundamental mode more stable and reduce the competition of higher-order modes. Therefore, expanding the volume of the fundamental mode helps the mode selection of the laser device, improves the output quality and consistency of the laser, and enhances the volume of the fundamental mode in the laser oscillation cavity, thereby optimizing the beam quality of the laser in the slow axis direction.

[0063] The present invention increases the volume of the fundamental mode in the stable cavity direction while maintaining the volume of the unstable cavity fundamental mode by adding a folding mirror structure in the hybrid cavity, changes the propagation direction of the laser beam, and expands it in the stable cavity direction, thereby increasing the volume of the fundamental mode and improving the beam quality. Increasing the volume of the fundamental mode by the folding mirror can reduce the number of starting transverse modes, thereby producing a laser beam with high beam quality in both the stable cavity and unstable cavity directions.

[0064] In the description of the present invention, it should be noted that the terms "upper", "lower", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0065] It should also be noted that, in the description of the present invention, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0066] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A hybrid cavity laser device, characterized in that: The laser device comprises a solid laser medium, a pump source, a first cavity mirror, a second cavity mirror, a folding mirror and a scraper mirror; The pump source is used to provide pump light for the solid laser medium; The solid laser medium is used to generate laser gain, the laser fast axis direction of the solid laser medium is the Y axis direction, and the laser slow axis direction of the solid laser medium is the Z axis direction; The first cavity mirror and the second cavity mirror are respectively arranged on both sides of the end face of the solid laser medium, and the first cavity mirror and the second cavity mirror constitute an optical resonant cavity for oscillating laser; The first cavity mirror and the second cavity mirror form an unstable cavity structure in the laser fast axis direction, and the first cavity mirror and the second cavity mirror form a stable cavity structure in the laser slow axis direction; The folding mirror is arranged between the solid laser medium and the second cavity mirror, and the folding mirror is used to fold the cavity length in the unstable cavity structure, and is used to increase the divergence angle of the laser beam in the stable cavity structure; The scraper mirror is arranged in the unstable cavity structure and is used to adjust the laser intensity and laser direction in the unstable cavity structure; The laser beam generated by the laser device is output through the second cavity mirror or the scraper mirror.

2. The laser device according to claim 1, characterized in that The folding mirror is a plane folding mirror in the unstable cavity structure; The folding mirror is a concave folding mirror or a convex folding mirror in the stable cavity structure.

3. The laser device according to claim 2, characterized in that: The number of the folding mirrors is one or more.

4. The laser device according to claim 1, characterized in that The first cavity mirror is a first concave mirror in the unstable cavity structure, and the second cavity mirror is a second concave mirror or a convex mirror in the unstable cavity structure; The first cavity mirror is a first concave mirror in the stable cavity structure, and the second cavity mirror is a plane mirror in the stable cavity structure.

5. The laser device according to claim 1, characterized in that The unstable cavity structure is a positive branch unstable cavity structure or a negative branch unstable cavity structure.

6. The laser device according to claim 5, characterized in that The unstable cavity structure is a coaxial unstable cavity structure or an off-axis unstable cavity structure.

7. The laser device according to claim 1, characterized in that: The solid laser medium is a solid laser medium whose cross section in the light transmission direction is rectangular, trapezoidal or elliptical.

8. The laser device according to claim 1, characterized in that An angle is set between the scraper mirror and the optical axis of the optical resonant cavity, and the scraper mirror is a perforated scraper mirror or a solid scraper mirror.

9. The laser device according to claim 8, characterized in that The scraper mirror is a hole-perforating scraper mirror, and the focal points of the first cavity mirror and the second cavity mirror coincide with the parallel light center axis of the hole-perforating scraper mirror; The scraper mirror is a solid scraper mirror, and the solid scraper mirror is placed away from one side of the solid laser medium.

10. The laser device according to claim 8, characterized in that The surface of the scraper mirror close to the folding mirror is coated with a high-reflective film for laser, which is used to reflect the output laser beam.

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