CN108988110A - A solid-state laser amplifier in the one-micron band - Google Patents

Abstract

The invention provides a solid laser amplifier with a micron wave band, which comprises: a high-brightness pump source system and a solid laser amplification system; the solid laser amplification system uses output light of the high-brightness pump source system as pump light; the high-brightness pump source system comprises at least one optical fiber laser with specific wavelength output and a focusing lens capable of enabling a light source to be coupled into the solid laser amplification system, wherein the output power of the optical fiber laser is not lower than 10W; the solid laser amplification system comprises at least one solid laser gain medium and at least one optical element, wherein the optical element is used for transmitting the pumping light projected by the high-brightness pumping source system and the laser beam needing to be amplified. The solid laser amplifier of the technical scheme can effectively weaken the influence of the thermal effect on the performance of the solid laser amplifier while obtaining larger pulse gain.

Description

A solid-state laser amplifier in the one-micron band

technical field

The invention relates to a solid-state laser amplifier, in particular to a solid-state laser amplifier with a micron wave band.

Background technique

Similar to solid-state lasers, solid-state laser amplifiers are laser amplifiers that use rare-earth-doped glass or rare-earth-doped crystals as gain media. When performing pulse amplification, solid-state laser amplifiers can provide high gain, so that the amplified pulses have high pulse energy. Solid-state laser amplifiers have a wide range of applications in the field of pulse amplification.

In a solid-state laser amplifier, the brightness of the pump source has a decisive effect on the gain that the solid-state laser amplifier can provide and the pulse energy that can be obtained after the pulse is amplified. At present, the semiconductor laser pump source is widely used in solid-state laser amplifiers. Compared with the traditional flash lamp pump source, the brightness of the output spot of the semiconductor laser pump source has been improved, but in order to improve the output coupling efficiency of the semiconductor laser, This type of pump source mostly uses multimode fiber output, so that the improvement of brightness is still limited. Choose from the brightness of the light source, the fiber laser is the next option for the pump source of the solid-state laser amplifier. When using a high-brightness light source such as a fiber laser as the pump source, because the overlap between the pump light and the signal light is strengthened, it can be Higher gain is obtained in the solid-state laser amplifier, which in turn results in higher pulse energy in the amplified pulse. At the same time, gain media with low doping concentrations and longer lengths can be used in solid-state laser amplifiers. In this way, due to the increase of the volume-to-area ratio of the gain medium, heat dissipation becomes easier, thereby reducing the influence of thermal effects on the performance of the laser amplifier.

Therefore, it is necessary to propose a method to increase the gain of a solid-state laser amplifier in the one-micron band during pulse amplification, so as to obtain greater pulse energy and solve the technical problem that the thermal effect of the solid-state laser has a large impact.

Contents of the invention

The technical problem to be solved by the present invention is to provide a solid-state laser amplifier for obtaining greater pulse gain while reducing the impact of thermal effects on the performance of the solid-state laser amplifier.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: a solid-state laser amplifier with a micron band, including: a high-brightness pump source system and a solid-state laser amplification system; the solid-state laser amplification system uses a high-brightness pump source The output light of the system is used as pump light;

The high-brightness pump source system includes at least one fiber laser with specific wavelength output and a focusing lens that can couple the light source into the solid-state laser amplification system, and the output power of the fiber laser is not lower than 10W;

The solid-state laser amplification system includes at least one solid-state laser gain medium and at least one optical element, and the optical element is used to transmit the pump light projected by the high-brightness pump source system and the laser beam to be amplified.

Further, the high-brightness pumping source system includes a high-power pumping source and a driving power supply, the driving power supply is electrically connected to the high-power pumping source, and the driving power supplies power to the high-power pumping source.

Further, the wavelength of the high-power pump source is within the absorption region of the doped rare earth elements.

Further, the focusing lens is arranged in front of the high-power pump source for coupling the laser light emitted by the high-power pump source.

Further, the fiber laser includes at least one semiconductor laser diode, a fiber signal pump combiner based on fused tapered technology and at least one section of rare earth-doped optical fiber.

Further, the fiber laser further includes at least one pair of reflective or transmissive Bragg gratings, which are used to form a fiber laser resonant cavity and perform wavelength selection.

Further, the fiber laser further includes a combination of at least one pair of fiber collimators and mirrors for forming a fiber laser resonator; at least one signal wavelength selector for wavelength selection.

Further, the signal wavelength selector is a narrow linewidth filter.

Further, the signal wavelength selector is a reflective Bragg grating that diffracts the selected wavelength.

Further, the solid-state laser gain medium is rare-earth-doped glass or rare-earth-doped crystal, including but not limited to neodymium-doped yttrium-aluminum garnet (Nd:YAG), ytterbium-doped yttrium-aluminum garnet (Yb:YAG), neodymium-doped Yttrium vanadate (Nd:YVO4), potassium gadolinium tungstate doped with neodymium (Nd:KGW), potassium gadolinium tungstate doped with ytterbium (Yb:KGW).

The beneficial effect of the present invention is that: the present invention uses a high-brightness light source such as a fiber laser as a pumping source, and the overlap between the pumping light and the signal light is strengthened, and a higher gain can be obtained in the solid-state laser amplifier, thereby making the amplified The pulse has higher pulse energy; at the same time, the gain medium with low doping concentration and longer length is used in the solid-state laser amplifier; the increase in the volume-to-area ratio of the gain medium makes heat dissipation easier, thereby reducing the thermal effect Effect on Laser Amplifier Performance.

Description of drawings

The specific structure of the present invention will be described in detail below in conjunction with the accompanying drawings.

Fig. 1 is the structural representation of an embodiment of the solid-state laser amplifier of a micron band of the present invention;

Among them, 1-high power pump source, 2-pump combiner, 3-high reflectivity fiber grating, 4-rare earth doped fiber, 5-partial reflection fiber grating, 6-focusing lens, 7-optical element, 8 - Solid state laser gain media.

Detailed ways

In order to describe the technical content, structural features, achieved goals and effects of the present invention in detail, the following will be described in detail in conjunction with the embodiments and accompanying drawings.

Refer to Figure 1 for the following technical solutions.

A solid-state laser amplifier in a micron band, comprising: a high-brightness pump source system and a solid-state laser amplification system; the solid-state laser amplification system uses the output light of the high-brightness pump source system as pump light;

The high-brightness pump source system includes at least one fiber laser with specific wavelength output and a focusing lens 6 that can couple the light source into the solid-state laser amplification system, and the output power of the fiber laser is not lower than 10W;

The solid-state laser amplification system includes at least one solid-state laser gain medium 8 and at least one optical element 7, and the optical element 7 is used to transmit the projected laser pump light and the laser beam to be amplified.

Preferably, the solid laser gain medium 8 is a rare earth-doped glass or a rare-earth doped crystal.

Wherein, the solid-state laser gain medium 8 is a solid-state laser amplifier that uses rare-earth-doped glass or rare-earth-doped crystals, including but not limited to neodymium-doped yttrium-aluminum garnet (Nd:YAG), ytterbium-doped yttrium-aluminum garnet ( Yb:YAG), Neodymium-doped Yttrium Vanadate (Nd:YVO4), Neodymium-doped Potassium Gadolinium Tungstate (Nd:KGW), Ytterbium-doped Potassium Gadolinium Tungstate (Yb:KGW), also includes temperature-controlled heating of the gain medium equipment.

The optical element 7 is anti-transmissive to the output wavelength of the laser beam that needs to be amplified and the fiber laser used as the pumping source.

It can be seen from the above description that the present invention uses a high-brightness light source such as a fiber laser as a pump source, and the overlap between the pump light and the signal light is strengthened, and a higher gain can be obtained in the solid-state laser amplifier, so that the amplified pulse has Higher pulse energy; at the same time, the gain medium with low doping concentration and longer length is used in the solid-state laser amplifier; the increase of the volume-to-area ratio of the gain medium makes heat dissipation easier, thereby reducing the thermal effect on the solid Influence of laser amplifier performance.

In a specific embodiment, the fiber laser includes a high-power pumping source 1 and a driving power supply, the driving power supply is electrically connected to the high-power pumping source 1, and the driving power supply supplies power to the high-power pumping source 1 .

Among them, the high-power pumping source 1 is composed of multiple multi-mode semiconductor lasers and a driving power supply. The power of each semiconductor laser is several watts or even tens of watts, and the output wavelength can be 975 nanometers, 940 nanometers, or 915 nanometers, preferably The wavelength used is 975 nm. Continuous or quasi-continuous output of the fiber laser is achieved by continuously supplying power to or modulating the high-brightness pump source 1 .

In a specific embodiment, the fiber laser includes at least one high-power pump source 1, a fiber signal pump combiner 2 based on fusion tapered technology, and at least one section of rare earth-doped optical fiber 4;

Preferably, the wavelength of the high-power pump source 1 is within the absorption region of the doped rare earth element;

Preferably, the pump beam combiner 2 is arranged in front of the high-power pump source 1 for coupling the laser light emitted by the high-power pump source 1;

Preferably, the fiber laser further includes at least one pair of reflective or transmissive Bragg gratings for forming a fiber laser cavity and performing wavelength selection;

Preferably, the fiber laser further includes a combination of at least one pair of fiber collimators and mirrors for forming a fiber laser cavity; at least one signal wavelength selector for wavelength selection;

Preferably, the signal wavelength selector is a narrow linewidth filter;

Preferably, the signal wavelength selector is a reflective Bragg grating that diffracts selected wavelengths.

Among them, the pump beam combiner 2 is an optical fiber pump beam combiner based on fusion tapered technology in this implementation case, which realizes the combination of multiple pump lights and signal lights; the reflective Bragg grating 3 and the partially reflective fiber grating 5 is the signal wavelength selection and fiber laser resonator reflection element combiner in this implementation case. At the same time, the high-brightness laser beam generated by the fiber laser is output by the partially reflective fiber grating 5 and coupled into the solid-state laser amplification system by the focusing lens 6 in front of the partially reflective fiber grating 5 .

The rare-earth-doped fiber 4 is the gain medium of the fiber laser in this embodiment, and the rare-earth element doped therein can be ytterbium or neodymium, which is selected according to the required output wavelength of the fiber laser. At the same time, according to different output requirements for fiber lasers, it can be used between single-clad rare-earth-doped fibers and double-clad rare-earth-doped fibers, between polarization-maintaining rare-earth-doped fibers and non-polarization-maintaining rare-earth-doped fibers, and with various core diameters. Choose between rare earth doped fibers and combine them.

In a specific embodiment, a solid-state laser amplifier in a micron waveband includes: a high-brightness pump source system and a solid-state laser amplification system;

The high-brightness pump source system includes: a fiber laser, the fiber laser includes a high-power pump source 1, a pump beam combiner 2 is arranged in front of the high-power pump source 1, and the pump beam combiner A reflective Bragg grating 3 is arranged in front of the laser 2, and a rare earth doped fiber 4 and a partially reflective fiber grating 5 are arranged in front of the reflective Bragg grating 3; meanwhile, the output power of the fiber laser is not lower than 10W.

Wherein, the high-power pumping source 1 is composed of n multi-mode semiconductor lasers and a driving power supply, each semiconductor laser has a power of several watts or even tens of watts, and its output wavelength can be 975 nanometers, 940 nanometers, or 915 nanometers, The preferred wavelength used is 975 nm. Continuous or quasi-continuous output of the fiber laser is realized by continuously supplying power to or modulating the high-power pumping source 1 .

The specific working mode of the solid-state laser amplifier pumped by a high-brightness light source in this implementation case is: a high-power pump source 1 with a wavelength of 914 nanometers, or 940 nanometers, or 976 nanometers, through the pump beam combiner 2 and high reflectivity The fiber grating 3 is coupled to the rare earth-doped fiber 4 doped with ytterbium, and the high-brightness fiber laser with a wavelength of 1005-1020 nanometers oscillated in the fiber laser resonator is output through the partially reflected fiber grating 5; then, the high-brightness fiber laser output The beam is collimated by the focusing lens 6 and coupled into the solid-state laser amplification system through the optical element 7 . In the solid-state laser amplification system, ytterbium-doped yttrium aluminum garnet (Yb:YAG) is used as the solid-state laser gain medium 8 to amplify and output the signal laser beam with a wavelength of 1030 nm.

The first, second... here only represent the distinction of their names, and do not mean that their importance and positions are different.

Here, up, down, left, right, front, and back only represent their relative positions and not their absolute positions.

The above is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related technologies fields, all of which are equally included in the scope of patent protection of the present invention.

Claims (10)

1. a kind of solid laser amplifier of a micron waveband, it is characterised in that: include: that high brightness pump source system and solid swash Optical amplification system；The Solid State Laser amplification system uses the output light of high brightness pump source system as pump light；

The high brightness pump source system includes, the optical fiber laser of at least one specific wavelength output and can make light source couples into Enter the condenser lens of the Solid State Laser amplification system, the output power of the optical fiber laser is not less than 10W；

The Solid State Laser amplification system includes at least one solid state laser gain medium and at least one optical element, described The laser beam that the pump light and needs that optical element is used to go out through high brightness pump source system projects amplify.

2. the solid state laser of a micron waveband as described in claim 1, it is characterised in that: the high brightness pump source system Including high power pump source and driving power, the driving power is electrically connected with high power pump source, and the driving power is given The high power pump source power supply.

3. the solid state laser of a micron waveband as claimed in claim 2, it is characterised in that: the optical fiber laser includes extremely A few semiconductor laser diode, a fiber-optic signal pump combiner based on fused biconical taper technology and at least one section are mixed dilute Native optical fiber.

4. the solid state laser of a micron waveband as claimed in claim 3, it is characterised in that: the wave in the high power pump source Grow rare earth doped element uptake zone in.

5. the solid laser amplifier of a micron waveband as claimed in claim 4, it is characterised in that: the condenser lens is set to In front of the high power pump source, the laser for projecting to high power pump source is coupled.

6. the solid state laser of a micron waveband as claimed in claim 2, it is characterised in that: the optical fiber laser further includes At least a pair of reflective or transmission-type Bragg grating, is used to form optical fiber laser resonant cavity and carries out wavelength selection.

7. the solid laser amplifier of a micron waveband as claimed in claim 2, it is characterised in that: the optical fiber laser is also Combination including at least a pair of of optical fiber collimator and reflecting mirror, is used to form optical fiber laser resonant cavity；At least one signal wavelength Selector, for carrying out wavelength selection.

8. the solid laser amplifier of a micron waveband as claimed in claim 7, it is characterised in that: the signal wavelength selection Device is narrow linewidth optical filter.

9. the solid laser amplifier of a micron waveband as claimed in claim 7, it is characterised in that: the signal wavelength selection Device is the reflective Bragg grating to selected wavelength diffractive.

10. the solid laser amplifier of a micron waveband as described in claim 1, it is characterised in that: the Solid State Laser increases Beneficial medium be doped rare earth element glass or doped rare earth element crystal, including but not limited to neodymium-doped yttrium-aluminum garnet (Nd:YAG), mix Ytterbium yttrium-aluminium-garnet (Yb:YAG), neodymium-doped tungstic acid gadolinium potassium (Nd:KGW), mixes ytterbium Gadolinium Tungstate potassium at Nd-doped yttrium vanadate (Nd:YVO4) (Yb:KGW)。