System for improving two-way amplification output laser beam quality

Abstract

The utility model discloses a system for improving the quality of a bi-pass amplification output laser beam, and the system comprises a seed laser generation module which is used for generating seed laser with a preset light spot size; the laser transmission module is used for transmitting the seed laser to the bi-pass amplification module; the bi-pass amplification module is used for amplifying the seed laser by adopting pump light, correcting and polarizing the amplified seed laser, and amplifying the corrected and polarized seed laser again; and the laser transmission module is also used for outputting the re-amplified seed laser. According to the utility model, the problem of light spot form deterioration in the bi-pass amplification process can be effectively avoided, and the light beam quality is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of lasers, and in particular relates to a system for improving the quality of a double-pass amplified output laser beam. Background Art

[0002] High-power and high-beam-quality pulsed lasers are widely used in laser micromachining, laser-induced imaging, medical treatment and other fields. Spatial optical amplifiers have advantages over fiber laser amplifiers, such as higher peak power, greater single-pulse energy, and narrower pulse width. Dual-pass amplifiers have many advantages over single-pass amplifiers, such as high gain, compact structure, and high efficiency. Therefore, dual-pass amplified lasers are an effective way to obtain high-quality processing in fields such as micromachining.

[0003] In the process of seed laser amplification of the double-pass amplified laser, it is necessary to pass through the doped spatial light amplifying medium twice. After the distortion-free seed laser passes through the amplifying medium once, the spot shape will deteriorate. After passing through the zero-degree reflector of the double-pass amplification and then passing through the amplifying medium again, the spot shape will deteriorate more seriously. Utility Model Content

[0004] In order to solve the above problems existing in the prior art, the utility model provides a system for improving the quality of a double-pass amplified output laser beam.

[0005] The technical problem to be solved by the utility model is achieved through the following technical solutions:

[0006] The utility model provides a system for improving the quality of a double-pass amplified output laser beam, comprising:

[0007] A seed laser generating module, used for generating a seed laser with a preset spot size;

[0008] A laser transmission module, used for transmitting the seed laser to a dual-pass amplification module;

[0009] The dual-pass amplification module is used to amplify the seed laser using pump light, correct and polarize the amplified seed laser, and re-amplify the corrected and polarized seed laser;

[0010] The laser transmission module is also used to output the seed laser after re-amplification.

[0011] In some embodiments, the dual-pass amplification module includes: a pump source, a doped amplification medium, and a correction and polarization submodule; the laser transmission module is specifically used to transmit the seed laser generated by the seed laser generation module to the doped amplification medium;

[0012] The pump source is used to generate the pump light;

[0013] The correction and polarization submodule is used to transmit the pump light to the doped amplifying medium, so as to adopt the pump light to amplify the seed laser transmitted to the doped amplifying medium, correct and polarize the amplified seed laser, and transmit the corrected and polarized seed laser to the doped amplifying medium for further amplification.

[0014] In some embodiments, the correction and polarization submodule includes: a dichroic mirror, a first combination mirror, and a second combination mirror; the dichroic mirror is located on one side of the pump source, the first combination mirror is located between the dichroic mirror and the pump source, the doped amplifying medium is located on the transmission light path of the dichroic mirror; the second combination mirror is located on the reflection light path of the dichroic mirror;

[0015] The first combination mirror is used to focus the pump light onto the dichroic mirror;

[0016] The dichroic mirror is used to transmit the pump light into the doped amplifying medium, and to reflect the amplified seed laser transmitted from the doped amplifying medium to the second combination mirror;

[0017] The second combination mirror is used to polarize and correct the amplified seed laser, and reflect the corrected and polarized seed laser to the dichroic mirror;

[0018] The dichroic mirror is also used to reflect the corrected and polarized seed laser into the doped amplifying medium for re-amplification.

[0019] In some embodiments, the first combination mirror includes: a first focusing mirror and a second focusing mirror; the first focusing mirror and the second focusing mirror are sequentially disposed between the dichroic mirror and the pump source.

[0020] In some embodiments, the second combined mirror includes: a λ / 4 wave plate, a third focusing mirror and a phase conjugate mirror;

[0021] The λ / 4 wave plate, the third focusing mirror and the phase conjugate mirror are sequentially arranged on the reflection light path of the dichroic mirror.

[0022] In some embodiments, the laser transmission module includes, in sequence: a first reflector, a λ / 2 wave plate, a polarization cube, and a second reflector;

[0023] The first reflecting mirror is used to reflect the seed laser generated by the seed laser generating module to the λ / 2 wave plate;

[0024] The λ / 2 wave plate is used to polarize the seed laser so that the polarized seed laser can pass through the polarization cube;

[0025] The second reflector is used to reflect the seed laser that has passed through the polarization cube to the dual-pass amplification module, and to reflect the re-amplified seed laser to the polarization cube;

[0026] The polarization cube is also used to output the re-amplified seed laser.

[0027] In some embodiments, the seed laser generation module includes: a seed light source, an isolator, and a fourth focusing mirror;

[0028] The seed light source is used to generate an original seed light source;

[0029] The fourth focusing mirror is used to focus the original seed light source passing through the isolator to obtain the seed laser with the preset spot size.

[0030] Compared with the prior art, the utility model has the following beneficial effects:

[0031] The utility model generates a seed laser with a preset spot size, adopts pump light and a doped amplifying medium to amplify the seed laser, corrects and polarizes the amplified seed laser, adopts pump light and a doped amplifying medium to amplify the corrected and polarized seed laser again, and finally outputs the amplified seed laser, which can effectively avoid the problem of spot morphology deterioration in the double-pass amplification process and improve the beam quality.

[0032] The utility model will be further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a flow chart of a system for improving the quality of a double-pass amplified output laser beam provided by an embodiment of the utility model;

[0034] Figure 2 It is a schematic diagram of the structure of an exemplary system for improving the quality of a double-pass amplified output laser beam provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0035] The present invention is further described in detail below in conjunction with specific embodiments, but the implementation methods of the present invention are not limited thereto.

[0036] The incident laser beam can be written as formula (1): E i =E0cos(kz-ωt)(1), where k=2π / λ, ω=2πθ / λ; the reflected light can be expressed as formula (2): E r=E0cos(-kz-ωt)(2). It can be seen that the reflected laser and the incident laser are completely consistent except for the propagation direction. Based on this theory, the utility model provides a system for improving the quality of the double-pass amplified output laser beam, so as to effectively avoid the problem of the deterioration of the light spot shape during the double-pass amplification process and improve the beam quality.

[0037] Figure 1 Schematic diagram of the structure of the system for improving the quality of the double-pass amplified output laser beam provided by the embodiment of the utility model. Figure 1 As shown, the system includes: a seed laser generation module, a laser transmission module, and a dual-pass amplification module. The seed laser generation module is used to generate a seed laser with a preset spot size; the laser transmission module is used to transmit the seed laser to the dual-pass amplification module; the dual-pass amplification module is used to amplify the seed laser using pump light, correct and polarize the amplified seed laser, and re-amplify the corrected and polarized seed laser; the laser transmission module is also used to output the re-amplified seed laser.

[0038] In some embodiments, the dual-pass amplification module includes: a pump source, a doped amplifying medium, and a correction and polarization submodule; the laser transmission module is specifically used to transmit the seed laser generated by the seed laser generation module to the doped amplifying medium; the pump source is used to generate pump light; the correction and polarization submodule is used to transmit the pump light to the doped amplifying medium, so as to use the pump light to amplify the seed laser transmitted to the doped amplifying medium, and correct and polarize the amplified seed laser, and transmit the corrected and polarized seed laser to the doped amplifying medium for further amplification.

[0039] In some embodiments, the correction and polarization submodule includes: a dichroic mirror, a first combination mirror and a second combination mirror; the dichroic mirror is located on one side of the pump source, the first combination mirror is located between the dichroic mirror and the pump source, and the doped amplifying medium is located on the transmission light path of the dichroic mirror; the second combination mirror is located on the reflection light path of the dichroic mirror; the first combination mirror is used to focus the pump light to the dichroic mirror; the dichroic mirror is used to transmit the pump light into the doped amplifying medium, and to reflect the amplified seed laser transmitted from the doped amplifying medium to the second combination mirror; the second combination mirror is used to polarize and correct the amplified seed laser, and reflect the corrected and polarized seed laser to the dichroic mirror; the dichroic mirror is also used to reflect the corrected and polarized seed laser into the doped amplifying medium for re-amplification.

[0040] In some embodiments, the first combination mirror includes: a first focusing mirror and a second focusing mirror; the first focusing mirror and the second focusing mirror are sequentially arranged between the dichroic mirror and the pump source.

[0041] In some embodiments, the second combined mirror includes: a λ / 4 wave plate, a third focusing mirror and a phase conjugate mirror; the λ / 4 wave plate, the third focusing mirror and the phase conjugate mirror are sequentially arranged on the reflection light path of the dichroic mirror.

[0042] In some embodiments, the laser transmission module includes, in sequence: a first reflector, a λ / 2 wave plate, a polarization cube, and a second reflector; the first reflector is used to reflect the seed laser generated by the seed laser generation module to the λ / 2 wave plate; the λ / 2 wave plate is used to polarize the seed laser so that the polarized seed laser can pass through the polarization cube; the second reflector is used to reflect the seed laser passing through the polarization cube to the dual-pass amplification module, and to reflect the re-amplified seed laser to the polarization cube; the polarization cube is also used to output the re-amplified seed laser.

[0043] In some embodiments, the seed laser generation module includes: a seed light source, an isolator and a fourth focusing mirror; the seed light source is used to generate an original seed light source; the fourth focusing mirror is used to focus the original seed light source passing through the isolator to obtain a seed laser with a preset spot size.

[0044] For example, Figure 2 This is an exemplary structural diagram of a system for improving the quality of a dual-pass amplified output laser beam provided by the utility model. Figure 2 As shown, the system includes a seed laser module, a λ / 2 wave plate, a polarization cube and a dual-pass amplifier module. The seed laser module includes: a seed laser, an isolator and a focusing mirror 1; the dual-pass amplifier module includes: a doped amplifier medium, a dichroic mirror, a focusing mirror 4, a focusing mirror 3, a pump LD, a λ / 4 wave plate, a focusing mirror 2 and a phase conjugate mirror. The seed laser emits a low-power, low-energy seed laser signal. After passing through the isolator, the seed laser signal is focused by the focusing mirror 1 to the spot size required by the dual-pass amplifier module. After that, it is reflected to the λ / 2 wave plate by the reflector 1. The λ / 2 wave plate polarizes the seed laser so that the polarized seed laser can pass through the polarization cube. The seed laser that passes through the polarization cube is reflected by the reflector 2 to the doped amplifier medium in the dual-pass amplifier module. At the same time, the pump LD provides the pump laser for dual-pass amplification. The focusing mirror 3 collimates the laser of the pump LD, and the focusing mirror 4 focuses the collimated pump laser. Focus to the dichroic mirror, the dichroic mirror is used to transmit the pump laser to the doped amplifying medium for amplifying the seed laser. After the amplified seed laser is transmitted to the dichroic mirror, it is reflected to the λ / 4 wave plate by the dichroic mirror. After passing through the λ / 4 wave plate, the seed laser is focused on the phase conjugate mirror by the focusing mirror 2. The phase conjugate mirror reflects the focused and amplified seed laser back to the doped amplifying medium along the original path for further amplification. The double-pass amplified laser beam is output through the polarization cube; wherein, the λ / 4 wave plate provides a relative phase to match the polarization direction of the polarization cube, so that the double-pass amplified laser beam is output.

[0045] The utility model generates a seed laser with a preset spot size, adopts pump light and a doped amplifying medium to amplify the seed laser, corrects and polarizes the amplified seed laser, adopts pump light and a doped amplifying medium to amplify the corrected and polarized seed laser again, and finally outputs the amplified seed laser, which can effectively avoid the problem of spot morphology deterioration in the double-pass amplification process and improve the beam quality.

[0046] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0047] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0048] In the specification, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality of components. Certain measures are recorded in different embodiments, but this does not mean that these measures cannot be combined to produce good effects.

[0049] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A system for improving the quality of a double-pass amplified output laser beam, characterized in that: include: A seed laser generating module, used for generating a seed laser with a preset spot size; A laser transmission module, used for transmitting the seed laser to a dual-pass amplification module; The dual-pass amplification module is used to amplify the seed laser using pump light, correct and polarize the amplified seed laser, and re-amplify the corrected and polarized seed laser; The laser transmission module is also used to output the seed laser after re-amplification.

2. The system for improving the quality of a double-pass amplified output laser beam according to claim 1, characterized in that: The dual-pass amplification module includes: a pump source, a doped amplification medium and a correction and polarization submodule; the laser transmission module is specifically used to transmit the seed laser generated by the seed laser generation module to the doped amplification medium; The pump source is used to generate the pump light; The correction and polarization submodule is used to transmit the pump light to the doped amplifying medium, so as to adopt the pump light to amplify the seed laser transmitted to the doped amplifying medium, correct and polarize the amplified seed laser, and transmit the corrected and polarized seed laser to the doped amplifying medium for further amplification.

3. The system for improving the quality of a double-pass amplified output laser beam according to claim 2, characterized in that: The correction and polarization submodule comprises: a dichroic mirror, a first combination mirror and a second combination mirror; the dichroic mirror is located on one side of the pump source, the first combination mirror is located between the dichroic mirror and the pump source, the doped amplifying medium is located on the transmission light path of the dichroic mirror; the second combination mirror is located on the reflection light path of the dichroic mirror; The first combination mirror is used to focus the pump light onto the dichroic mirror; The dichroic mirror is used to transmit the pump light into the doped amplifying medium, and to reflect the amplified seed laser transmitted from the doped amplifying medium to the second combination mirror; The second combination mirror is used to polarize and correct the amplified seed laser, and reflect the corrected and polarized seed laser to the dichroic mirror; The dichroic mirror is also used to reflect the corrected and polarized seed laser into the doped amplifying medium for re-amplification.

4. The system for improving the quality of a double-pass amplified output laser beam according to claim 3, characterized in that: The first combination mirror comprises: a first focusing mirror and a second focusing mirror; the first focusing mirror and the second focusing mirror are sequentially arranged between the dichroic mirror and the pump source.

5. The system for improving the quality of double-pass amplified output laser beam according to claim 3, characterized in that: The second combined mirror comprises: a λ / 4 wave plate, a third focusing mirror and a phase conjugate mirror; The λ / 4 wave plate, the third focusing mirror and the phase conjugate mirror are sequentially arranged on the reflection light path of the dichroic mirror.

6. The system for improving the quality of dual-pass amplified output laser beam according to claim 1, characterized in that: The laser transmission module includes, in sequence: a first reflector, a λ / 2 wave plate, a polarization cube, and a second reflector; The first reflecting mirror is used to reflect the seed laser generated by the seed laser generating module to the λ / 2 wave plate; The λ / 2 wave plate is used to polarize the seed laser so that the polarized seed laser can pass through the polarization cube; The second reflector is used to reflect the seed laser that has passed through the polarization cube to the dual-pass amplification module, and to reflect the re-amplified seed laser to the polarization cube; The polarization cube is also used to output the re-amplified seed laser.

7. The system for improving the quality of a double-pass amplified output laser beam according to claim 1, characterized in that: The seed laser generation module comprises: a seed light source, an isolator and a fourth focusing mirror; The seed light source is used to generate an original seed light source; The fourth focusing mirror is used to focus the original seed light source passing through the isolator to obtain the seed laser with the preset spot size.

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