CN212935130U - Tunable near-infrared all-fiber structure gas Raman laser - Google Patents
Tunable near-infrared all-fiber structure gas Raman laser Download PDFInfo
- Publication number
- CN212935130U CN212935130U CN202021518248.4U CN202021518248U CN212935130U CN 212935130 U CN212935130 U CN 212935130U CN 202021518248 U CN202021518248 U CN 202021518248U CN 212935130 U CN212935130 U CN 212935130U
- Authority
- CN
- China
- Prior art keywords
- fiber
- hollow
- laser
- raman
- optical fiber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Lasers (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
Abstract
The utility model provides a gaseous raman laser of tunable near-infrared all-fiber structure, including pumping source, hollow optic fibre, filtering output device, during the pumping laser of pumping source output got into the fibre core of hollow optic fibre through real core fiber coupling, it had the gaseous restraint pumping laser transmission simultaneously of raman gain to fill in the fibre core of hollow optic fibre, and the output real core fiber coupling of hollow optic fibre are connected, are equipped with filtering output device on the real core optic fibre of output. The hollow-core optical fiber provides an environment for long-range interaction of the pump laser and the Raman gain gas, and plays a role in inhibiting other Raman spectral lines from being generated. The utility model adopts the all-fiber structure, and has the advantages of compact structure and convenient carrying.
Description
Technical Field
The utility model belongs to the technical field of the laser instrument, a gaseous raman laser of tunable near-infrared all-fiber structure is related to.
Background
The lasers with the diameters of 1.5 mu m, 1.7 mu m, 2 mu m and the like have important application values in the fields of optical fiber communication, biomedical treatment, environmental monitoring and industrial processing. Tunable laser light sources with narrow line width, high peak power of 1.5 μm, 1.7 μm, 2 μm and the like provide ideal light sources for generation of supercontinuum, realization of infrared gas laser and generation of optical parametric oscillation.
At present, laser light sources of 1.5 microns, 1.7 microns, 2 microns and the like are mainly obtained through a solid glass fiber laser doped with rare earth ions, but the bottleneck problem of power improvement exists due to low damage threshold and strong nonlinear effect of the solid doped fiber. Although laser outputs of 1.5 μm, 1.7 μm, 2 μm, and the like with high peak power can be obtained by technical means such as mode locking, Q-switching, and the like, the spectrum of the laser is broadened due to nonlinear effects caused by transmission of the laser with high peak power in a solid core fiber, and it is difficult to realize narrow-linewidth output. Therefore, the conventional rare earth ion doped solid glass fiber laser cannot simultaneously realize the output of narrow linewidth and high peak power. The fiber gas Raman laser which is widely paid attention in recent years provides a brand new idea for realizing the output of fiber laser with wave bands of 1.5 microns, 1.7 microns, 2 microns and the like.
The gas is used as a laser working medium, and has the advantages of quick heat dissipation and high damage threshold. The stimulated raman scattering effect of the gas molecules on the laser light may produce a laser radiation frequency shift. Stimulated raman scattering is an inelastic collision with no particular requirement for the pump laser wavelength, and the resulting laser radiation frequency shift depends on the energy level structure of the molecule. Gas stimulated raman scattering has received extensive attention since its first report in 1963 and has proven to be an effective means of generating tunable, new wavelength lasers. Historically, the pumping threshold for achieving stimulated raman scattering of gases in free space has been high, subject to very short effective working distances, and raman scattering at different raman shifts as well as higher order raman scattering may occur, making conversion to specific raman wavelengths very inefficient.
In order to enhance the interaction between light and gas, a hollow capillary glass tube and a high-precision Fabry-Perot cavity are adopted, but the effective acting distance is very limited, and the conversion efficiency is still low. The appearance of the hollow-core optical fiber provides an almost ideal environment for gas stimulated Raman scattering, the hollow-core optical fiber can effectively restrain pump light in a fiber core with micron order, the pump intensity and the interaction distance are greatly improved, the loss of each Raman signal can be controlled by reasonably designing an optical fiber transmission loss spectrum, the generation of unnecessary spectral lines is inhibited, and the efficient Raman conversion to the required wavelength is possible.
SUMMERY OF THE UTILITY MODEL
To the technical problem that prior art exists, the utility model provides a gaseous raman laser of tunable near-infrared all-fiber structure.
Specifically, the utility model discloses a technical scheme do:
the utility model provides a technical scheme one, a gaseous raman laser of tunable near-infrared all-fiber structure, including pumping source, hollow optic fibre, filtering output device, during the pumping laser of pumping source output got into the fibre core of hollow optic fibre through real core fiber coupling, it has the gaseous restraint pumping laser transmission simultaneously of raman gain to fill in the fibre core of hollow optic fibre, and the output real core fiber coupling of hollow optic fibre are connected, are equipped with filtering output device on the real core optic fibre of output. The hollow-core optical fiber provides an environment for long-range interaction of the pump laser and the Raman gain gas, and plays a role in inhibiting other Raman spectral lines from being generated.
In the first technical scheme, as a preferable scheme, the pumping source is a fiber laser or a fiber amplifier with a wave band of 1 μm; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the raman gain gas is methane, and can frequency shift 1 μm pump laser to 1.5 μm band by stimulated raman scattering effect. The hollow-core optical fiber adopts an anti-resonance hollow-core optical fiber, such as a node-free type or a conjoined type anti-resonance hollow-core optical fiber. The hollow-core fiber has very low transmission loss for pump laser in a 1 mu m wave band and Raman laser in a 1.5 mu m wave band, and has higher transmission loss for laser in other wave bands. For the narrow transmission band range of the hollow-core photonic crystal fiber, the band range of 1 μm to 1.5 μm cannot be covered at present, but the transmission band range of the anti-resonance hollow-core fiber is wider, so the anti-resonance hollow-core fiber is adopted in the scheme.
In the first technical solution, as a preferred solution, the pump source is a fiber laser or a fiber amplifier with a 1.55 μm waveband; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman gain gas is H2Or D2The gas can frequency shift the 1.55 μm pump laser to the 1.7 μm band by the stimulated Raman scattering effect. The hollow-core optical fiber, namely the hollow-core photonic crystal optical fiber, has very low transmission loss for pump laser with a wave band of 1.55 mu m and Raman laser with a wave band of 1.7 mu m, and has higher transmission loss for laser with other wave bands. For the 1.7 mu m wave band, because the pumping wave band and the Raman wave band are very close, the hollow core photon crystalThe bulk optical fiber can cover the pumping wavelength and the Raman wavelength, and meanwhile, the high-order Raman wavelength is basically located outside a transmission band and is not easy to generate, so that the hollow-core photonic crystal fiber is used. In the first technical solution, as a preferred solution, the pump source is a fiber laser or a fiber amplifier with a 1.9 μm waveband; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman-enhanced gas is D2The gas can shift the pump laser of 1.9 μm wave band to 2 μm wave band by stimulated Raman scattering effect. The hollow-core optical fiber, namely the hollow-core photonic crystal optical fiber, has very low transmission loss for Raman laser with a wave band of 1.9-2.2 mu m, and has higher transmission loss for laser with other wave bands. For the 2 mu m waveband, the hollow-core photonic crystal fiber can cover the pumping wavelength and the Raman wavelength because the pumping waveband and the Raman waveband are very close, and meanwhile, the high-order Raman wavelength is basically positioned outside a transmission band and is not easy to generate, so the hollow-core photonic crystal fiber is used.
In the first technical solution, as a preferred embodiment, the filtering output device includes a long-period fiber grating having a center wavelength of a pumping wavelength, and a cladding light filter, where the long-period fiber grating couples the residual pumping laser in forward transmission to the cladding for forward transmission, and the cladding light filter is configured to filter the residual pumping laser coupled to the cladding.
In the first technical solution, as a preferred embodiment, the input end of the hollow-core optical fiber is connected with the solid-core output pigtail of the pumping source by means of fusion splicing, and the output end of the hollow-core optical fiber is connected with the input end of the solid-core single-mode optical fiber provided with the filtering output device by means of fusion splicing, so as to seal the gas inside the hollow-core optical fiber.
As another technical solution of the present invention, a second technical solution is provided, in which the tunable near-infrared all-fiber gas raman laser includes a pumping source, a seed source, a wavelength division multiplexer, a hollow fiber, and a filter output device, wherein a solid output tail fiber of the pumping source is connected to the wavelength division multiplexer, a solid output tail fiber of the seed source is connected to the wavelength division multiplexer, and the wavelength division multiplexer combines the pumping laser output by the pumping source and the seed output by the seed source into one path; the solid output tail fiber of the wavelength division multiplexer is coupled with the hollow fiber, Raman gain gas is filled in the fiber core of the hollow fiber, the hollow fiber provides an environment for long-range interaction of pump laser, seed light and working gas, the output end of the hollow fiber is coupled with the output end solid fiber, and the output end solid fiber is provided with a filtering output device.
In the second technical scheme, as a preferable scheme, the pumping source is a continuous fiber laser or a fiber amplifier with a wave band of 1 μm; the seed source is a continuous semiconductor laser with a wave band of 1.5 mu m; the raman gain gas is methane. The hollow-core optical fiber, namely the anti-resonance hollow-core optical fiber, has very low transmission loss for pump laser of a 1 mu m wave band and Raman laser of a 1.5 mu m wave band, and has higher transmission loss for laser of other wave bands.
In the second technical solution, as a preferred solution, the pump source is a continuous fiber laser or a fiber amplifier with a 1.55 μm waveband; the seed source is a continuous semiconductor laser with a wave band of 1.7 mu m; the Raman gain gas is H2Or D2A gas. The hollow-core optical fiber, namely the hollow-core photonic crystal optical fiber, has very low transmission loss for pump laser with a wave band of 1.55 mu m and Raman laser with a wave band of 1.7 mu m, and has higher transmission loss for laser with other wave bands.
In the second technical solution, as a preferred solution, the pump source is a continuous fiber laser or a fiber amplifier with a 1.9 μm waveband; the seed source is a continuous semiconductor laser with a wave band of 2 mu m; the Raman-enhanced gas is D2A gas. The hollow-core optical fiber, namely the hollow-core photonic crystal optical fiber, has very low transmission loss for Raman laser with a wave band of 1.9-2.2 mu m, and has higher transmission loss for laser with other wave bands.
In the second technical solution, as a preferred embodiment, the filtering output device includes a long-period fiber grating having a center wavelength of a pumping wavelength, and a cladding light filter, where the long-period fiber grating couples the residual pumping laser in forward transmission to the cladding for forward transmission, and the cladding light filter is configured to filter the residual pumping laser coupled to the cladding.
In the second technical scheme, as a preferable scheme, the input end of the hollow optical fiber is connected with the solid output tail fiber of the wavelength division multiplexer in a fusion welding mode, and the output end of the hollow optical fiber is connected with the input end of the solid single-mode optical fiber provided with the filtering output device in a fusion welding mode, so that the gas inside the hollow optical fiber is sealed.
Compared with the prior art, the utility model has the advantages of:
(1) the utility model provides a gaseous laser generator of optic fibre for producing raman laser.
(2) The utility model adopts the all-fiber structure, and has the advantages of compact structure and convenient carrying.
(3) The hollow optical fiber adopted by the utility model provides a very long effective action distance for the interaction of the pumping laser and the working gas, thereby greatly reducing the pumping threshold value; by reasonably designing the transmission loss spectrum of the optical fiber, other spectral lines can be suppressed, and the output of the required spectral lines is realized.
(4) The utility model discloses utilize long period fiber grating to combine the method realization of covering light filter ware to the filtering of remaining pumping laser, have simple structure, convenient operation's advantage.
(5) The utility model discloses it is high to combine gas laser output, and the damage threshold value is high and the advantage that fiber laser light beam quality is good, has very big potential advantage in practical application.
Drawings
FIG. 1 is a cross-sectional electron microscope image of a node-free type antiresonant hollow-core fiber.
FIG. 2 is a cross-sectional electron microscope image of a conjoined antiresonant hollow-core fiber.
FIG. 3 is a schematic cross-sectional view of a hollow core photonic crystal fiber.
FIG. 4 is a schematic representation of the loss spectrum of a hollow core fiber.
FIG. 5 is a schematic diagram of the transmission spectrum of a long-period fiber grating.
Fig. 6 is a schematic structural diagram of a first tunable near-infrared all-fiber structure gas raman laser.
Fig. 7 is a schematic structural diagram of a second tunable near-infrared all-fiber structure gas raman laser.
Illustration of the drawings:
1. a pump source; 2. inputting end welding points; 3. a hollow-core optical fiber; 4. welding points at the output end; 5. a long-period fiber grating; 6. a cladding light filter; 7. a seed source; 8. a wavelength division multiplexer.
Detailed Description
The invention is further described with reference to the drawings and the specific embodiments.
FIG. 1 is a cross-sectional electron microscope image of a node-free type antiresonant hollow-core fiber. FIG. 2 is a cross-sectional electron microscope image of a conjoined antiresonant hollow-core fiber. FIG. 3 is a schematic cross-sectional view of a hollow core photonic crystal fiber. Fig. 4 shows a schematic diagram of the transmission loss spectrum of such a hollow core fiber. The transmission band range of the hollow-core photonic crystal fiber is generally narrow, and for hydrogen or deuterium stimulated Raman scattering, the hollow-core photonic crystal fiber only comprises a pumping wavelength and a first-order rotating Raman wavelength, and the vibration Raman laser and the high-order rotating Raman laser are generally positioned outside the transmission band, so that the generation of the first-order rotating Raman laser in a 1.7 or 2 mu m wave band is facilitated. The hollow-core optical fiber without nodes and in a connected mode has a relatively wide transmission band range, pumping wavelength and first-order vibration Raman wavelength can be covered for methane stimulated Raman scattering, and the high-order vibration Raman wavelength is located outside the transmission band range, so that generation of first-order vibration Raman laser in a 1.5-micrometer wave band is facilitated.
Fig. 5 shows a schematic diagram of the transmission spectrum of a long period fiber grating in a filter device. The transmission spectrum shows that the pump laser has extremely low transmittance, so that the pump laser cannot pass through the long-period fiber grating; the Raman laser transmittance is nearly 100%, so that the long-period fiber grating has no influence on the Raman laser transmission. And according to the principle of the long-period fiber grating, the pump laser which cannot penetrate is coupled into the cladding for transmission, and the cladding light filter can be used for filtering the pump laser. Therefore, the long-period fiber grating combined with the cladding light filter can achieve the filtering effect.
Example 1:
fig. 6 is a schematic structural diagram of a first tunable near-infrared all-fiber structured gas raman laser, and this embodiment adopts a structure of the first tunable near-infrared all-fiber structured gas raman laser to provide a all-fiber structured 1.5 μm band gas raman laser, which includes a pump source 1, an input end fusion point 2, a hollow fiber 3, an output end fusion point 4, a long-period fiber grating 5, and a cladding optical filter 6. The pumping source is a 1-micron wave band optical fiber laser or an optical fiber amplifier; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the raman gain gas is methane, and can frequency shift 1 μm pump laser to 1.5 μm band by stimulated raman scattering effect. The hollow-core optical fiber adopts an anti-resonance hollow-core optical fiber, has very low transmission loss for pump laser of a 1 mu m wave band and Raman laser of a 1.5 mu m wave band, and has higher transmission loss for laser of other wave bands.
A continuous or pulse fiber laser or an amplifier with a tunable 1-micron waveband is used as a pumping source 1, and the tunable 1-micron waveband pumping laser generated by the pumping source 1 is coupled into a fiber core of a hollow-core fiber 3 through a solid-core output tail fiber of the pumping source 1. The solid output tail fiber of the pump source 1 is coupled with the hollow fiber 3, and the coupling position forms an input end fusion point 2.
The core of the hollow-core optical fiber 3 is filled with Raman gain gas CH and simultaneously restrains pumping laser transmission4. The fiber core of the hollow-core optical fiber 3 is filled with Raman gain gas and simultaneously restrains pumping laser transmission, so that an ideal environment is provided for the interaction of working gas and pumping laser. Take 1064nm pump laser as an example, due to CH4The main vibration rotation Raman frequency shift coefficient is about 2917cm-1Using CH4As the working gas, the Raman laser output of 1543nm can be realized. When the pump wavelength is tunable, a tunable raman laser output can be generated.
The output end of the hollow optical fiber 3 is coupled with the output end solid optical fiber, and the coupling connection position forms an output end fusion point 4. And the output end solid optical fiber is provided with a filtering output device. The Raman laser and the residual pump laser generated in the hollow-core optical fiber pass through an output end fusion joint 4 between the hollow-core optical fiber 3 and an output end solid-core optical fiber, enter a filter device to filter the residual pump laser and then are output. Wherein, the residual pump laser is coupled to the cladding for transmission through the long-period fiber grating 5 and then filtered by the cladding light filter 6; the raman laser light is directly output through the long period fiber grating 5 and the cladding light filter 6.
Example 2:
fig. 7 is a schematic structural diagram of a second tunable near-infrared all-fiber structured gas raman laser, and this embodiment adopts a structure of the second tunable near-infrared all-fiber structured gas raman laser to provide a all-fiber structured 1.5 μm band gas raman laser, which includes a pump source 1, an input end fusion point 2, a hollow fiber 3, an output end fusion point 4, a long-period fiber grating 5, a cladding optical filter 6, a seed source 7, and a wavelength division multiplexer 8. The pumping source is a fiber laser or a fiber amplifier with a wave band of 1 mu m, and the pumping source is continuously output; the seed source is a continuous semiconductor laser with a wave band of 1.5 mu m; the raman gain gas is methane. The hollow-core optical fiber adopts an anti-resonance hollow-core optical fiber, has very low transmission loss for pump laser of a 1 mu m wave band and Raman laser of a 1.5 mu m wave band, and has higher transmission loss for laser of other wave bands.
The solid output tail fiber of the pumping source 1 is connected with a wavelength division multiplexer 8, the solid output tail fiber of the seed source 7 is connected with the wavelength division multiplexer 8, and the wavelength division multiplexer 8 combines the pumping laser of 1 micron wave band output by the pumping source and the seed of 1.5 micron wave band output by the seed source into one path. The solid output tail fiber of the wavelength division multiplexer 8 is coupled with the hollow-core optical fiber 3.
The core of the hollow-core optical fiber 3 is filled with working gas CH4The hollow-core optical fiber 3 provides an environment for long-range interaction of pump laser, seed light and working gas, the output end of the hollow-core optical fiber 3 is coupled with the output end solid-core optical fiber, and the output end solid-core optical fiber is provided with a filtering output device. The input end of the hollow-core optical fiber 3 is connected with the solid-core output tail fiber of the wavelength division multiplexer 8 in a fusion mode, and the input end fusion point 2 is formed at the coupling connection position.
The output end of the hollow-core optical fiber 3 is connected with the input end of the solid-core single-mode optical fiber provided with the filtering output device in a welding mode, and the coupling connection position forms outputEnd weld points 4. This achieves the sealing of the gas inside the hollow-core optical fiber. The pump laser and the seed light which are synthesized into one path for transmission enter the hollow-core optical fiber and are filled with CH4The gas generates stimulated Raman scattering effect, and then the seed laser is amplified in the process of transmitting in the hollow optical fiber 3. The amplified Raman laser and the amplified residual pump laser enter the filtering output device through the output end welding point 4 and are output. The filtering output device is used for filtering residual pump light and outputting 1.5 mu m waveband Raman laser. Wherein, the residual pump laser is coupled to the cladding for transmission through the long-period fiber grating 5 and then filtered by the cladding light filter 6; the raman laser light is directly output through the long period fiber grating 5 and the cladding light filter 6.
The 1.5 μm and 1.5 μm wave bands mentioned in the above scheme mean that both lasers can output near the wavelength point. The working wavelength of the 1 mu m waveband optical fiber laser pumping source and the 1.5 mu m waveband seed source is set, so that the laser output with the specific wavelength in the 1.5 mu m waveband range can be realized.
Example 3:
fig. 6 is a schematic structural diagram of a first tunable near-infrared all-fiber structured gas raman laser, and this embodiment adopts a structure of the first tunable near-infrared all-fiber structured gas raman laser to provide a all-fiber structured 1.7 μm band gas raman laser, which includes a pump source 1, an input end fusion point 2, a hollow fiber 3, an output end fusion point 4, a long-period fiber grating 5, and a cladding optical filter 6. The pumping source is a fiber laser or a fiber amplifier with a wave band of 1.55 mu m; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman gain gas is H2Or D2The gas can frequency shift the 1.55 μm pump laser to the 1.7 μm band by the stimulated Raman scattering effect. The hollow-core optical fiber adopts a hollow-core photonic crystal optical fiber, has very low transmission loss for pump laser with a wave band of 1.55 mu m and Raman laser with a wave band of 1.7 mu m, and has higher transmission loss for laser with other wave bands.
A continuous or pulse fiber laser or an amplifier with a tunable waveband of 1.55 mu m is used as a pumping source 1, and the tunable pumping laser with the waveband of 1.55 mu m generated by the pumping source 1 is coupled into a fiber core of a hollow-core fiber 3 through a solid-core output tail fiber of the pumping source 1. The solid output tail fiber of the pump source 1 is coupled with the hollow fiber 3, and the coupling position forms an input end fusion point 2.
The fiber core of the hollow-core optical fiber 3 is filled with Raman gain gas H for restricting pumping laser transmission2And D2One of two gases. The fiber core of the hollow-core optical fiber 3 is filled with Raman gain gas and simultaneously restrains pumping laser transmission, so that an ideal environment is provided for the interaction of working gas and pumping laser. Take 1550nm pump laser as an example, because of H2Has a main rotational Raman frequency shift coefficient of about 587cm-1Using H2As working gas, 1705nm Raman laser output can be realized; due to D2Has a main rotational Raman frequency shift coefficient of about 415cm-1Using D2As the working gas, 1657nm Raman laser output can be realized. When the pump wavelength is tunable, a tunable raman laser output can be generated.
The output end of the hollow optical fiber 3 is coupled with the output end solid optical fiber, and the coupling connection position forms an output end fusion point 4. And the output end solid optical fiber is provided with a filtering output device. The Raman laser and the residual pump laser generated in the hollow-core optical fiber pass through an output end fusion joint 4 between the hollow-core optical fiber 3 and an output end solid-core optical fiber, enter a filter device to filter the residual pump laser and then are output. Wherein, the residual pump laser is coupled to the cladding for transmission through the long-period fiber grating 5 and then filtered by the cladding light filter 6; the raman laser light is directly output through the long period fiber grating 5 and the cladding light filter 6.
Example 4:
fig. 7 is a schematic structural diagram of a second tunable near-infrared all-fiber structured gas raman laser, and this embodiment adopts a structure of the second tunable near-infrared all-fiber structured gas raman laser to provide a all-fiber structured 1.7 μm band gas raman laser, which includes a pump source 1, an input end fusion point 2, a hollow fiber 3, an output end fusion point 4, a long-period fiber grating 5, a cladding optical filter 6, a seed source 7, and a wavelength division multiplexer 8. The above-mentionedThe pumping source is a fiber laser or a fiber amplifier with a wave band of 1.55 mu m; the pumping source is continuously output; the seed source is a continuous semiconductor laser with a wave band of 1.7 mu m; the Raman gain gas is H2Or D2A gas. The hollow-core optical fiber, namely the hollow-core photonic crystal optical fiber, has very low transmission loss for pump laser with a wave band of 1.55 mu m and Raman laser with a wave band of 1.7 mu m, and has higher transmission loss for laser with other wave bands.
The solid output tail fiber of the pumping source 1 is connected with a wavelength division multiplexer 8, the solid output tail fiber of the seed source 7 is connected with the wavelength division multiplexer 8, and the wavelength division multiplexer 8 combines the pumping laser of 1.55 mu m wave band output by the pumping source and the seed of 1.7 mu m wave band output by the seed source into one path. The solid output tail fiber of the wavelength division multiplexer 8 is coupled with the hollow-core optical fiber 3.
The core of the hollow-core optical fiber 3 is filled with Raman gain gas H2And D2One of the two gases, the hollow-core optical fiber 3 provides an environment for long-range interaction of the pump laser, the seed light and the Raman gain gas, the output end of the hollow-core optical fiber 3 is coupled with the output end solid-core optical fiber, and the output end solid-core optical fiber is provided with a filtering output device. The input end of the hollow-core optical fiber 3 is connected with the solid-core output tail fiber of the wavelength division multiplexer 8 in a fusion mode, and the input end fusion point 2 is formed at the coupling connection position.
The output end of the hollow-core optical fiber 3 is connected with the input end of the solid-core single-mode optical fiber provided with the filtering output device in a fusion welding mode, and the coupling connection position forms an output end fusion point 4. This achieves the sealing of the gas inside the hollow-core optical fiber. The synthesized pump laser and seed light enter the hollow-core optical fiber, and generate stimulated Raman scattering effect with the Raman gain gas filled in the hollow-core optical fiber, and then the seed laser is amplified in the process of transmission in the hollow-core optical fiber 3. The amplified Raman laser and the amplified residual pump laser enter the filtering output device through the output end welding point 4 and are output. The filtering output device is used for filtering residual pump light and outputting 1.7 mu m waveband Raman laser. Wherein, the residual pump laser is coupled to the cladding for transmission through the long-period fiber grating 5 and then filtered by the cladding light filter 6; the raman laser light is directly output through the long period fiber grating 5 and the cladding light filter 6.
The 1.7 μm and 1.7 μm wavelength bands mentioned herein mean that both laser light in the vicinity of the wavelength point can be output. By setting the working wavelength of the 1.55 mu m waveband optical fiber laser pumping source and the 1.7 mu m waveband seed source and selecting the type of the working gas, the laser output with specific wavelength in the 1.7 mu m waveband range can be realized.
Example 5:
fig. 6 is a schematic structural diagram of a first tunable near-infrared all-fiber structure gas raman laser, and this embodiment adopts a structure of the first tunable near-infrared all-fiber structure gas raman laser to provide a 2 μm-band gas raman laser with an all-fiber structure, which includes a pump source 1, an input end fusion point 2, a hollow-core fiber 3, an output end fusion point 4, a long-period fiber grating 5, and a cladding optical filter 6. The pumping source is a fiber laser or a fiber amplifier with a wave band of 1.9 mu m; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman-enhanced gas is D2The gas can shift the pump laser of 1.9 μm wave band to 2 μm wave band by stimulated Raman scattering effect. The hollow-core optical fiber adopts a hollow-core photonic crystal optical fiber, has very low transmission loss for Raman laser with a wave band of 1.9-2.2 mu m, and has higher transmission loss for laser with other wave bands.
A continuous or pulse fiber laser or an amplifier with a tunable waveband of 1.9 mu m is used as a pumping source 1, and the tunable pumping laser with the waveband of 1.9 mu m generated by the pumping source 1 is coupled into a fiber core of a hollow-core fiber 3 through a solid-core output tail fiber of the pumping source 1. The solid output tail fiber of the pump source 1 is coupled with the hollow fiber 3, and the coupling position forms an input end fusion point 2.
The fiber core of the hollow-core optical fiber 3 is filled with Raman gain gas D and simultaneously restrains pumping laser transmission2A gas. The fiber core of the hollow-core optical fiber 3 is filled with Raman gain gas and simultaneously restrains pumping laser transmission, so that an ideal environment is provided for the interaction of working gas and pumping laser. Take 1950nm pump laser as an example, since D2Has a main rotational Raman frequency shift coefficient of about 415cm-1If the pump laser wavelength is 1950nm, 2122nm Raman laser output can be realized. When the pump wavelength is tunable, a tunable raman laser output can be generated.
The output end of the hollow optical fiber 3 is coupled with the output end solid optical fiber, and the coupling connection position forms an output end fusion point 4. And the output end solid optical fiber is provided with a filtering output device. The Raman laser and the residual pump laser generated in the hollow-core optical fiber pass through an output end fusion joint 4 between the hollow-core optical fiber 3 and an output end solid-core optical fiber, enter a filter device to filter the residual pump laser and then are output. Wherein, the residual pump laser is coupled to the cladding for transmission through the long-period fiber grating 5 and then filtered by the cladding light filter 6; the raman laser light is directly output through the long period fiber grating 5 and the cladding light filter 6.
Example 6:
fig. 7 is a schematic structural diagram of a second tunable near-infrared all-fiber structured gas raman laser, and this embodiment adopts a structure of the second tunable near-infrared all-fiber structured gas raman laser to provide a 2 μm-band gas raman laser with an all-fiber structure, which includes a pump source 1, an input end fusion point 2, a hollow fiber 3, an output end fusion point 4, a long-period fiber grating 5, a cladding optical filter 6, a seed source 7, and a wavelength division multiplexer 8. The pumping source is a fiber laser or a fiber amplifier with a wave band of 1.9 mu m; the pumping source is continuously output; the seed source is a continuous semiconductor laser with a wave band of 2 mu m; the Raman-enhanced gas is D2A gas. The hollow-core optical fiber, namely the hollow-core photonic crystal optical fiber, has very low transmission loss for Raman laser with a wave band of 1.9-2.2 mu m, and has higher transmission loss for laser with other wave bands.
The solid output tail fiber of the pumping source 1 is connected with a wavelength division multiplexer 8, the solid output tail fiber of the seed source 7 is connected with the wavelength division multiplexer 8, and the wavelength division multiplexer 8 combines the pumping laser of 1.9 mu m wave band output by the pumping source and the seed of 2 mu m wave band output by the seed source into one path. The solid output tail fiber of the wavelength division multiplexer 8 is coupled with the hollow-core optical fiber 3.
The core of the hollow-core optical fiber 3 is filled with Raman gain gas D2Gas (es)The hollow-core optical fiber 3 provides an environment for long-range interaction of pump laser, seed light and Raman gain gas, the output end of the hollow-core optical fiber 3 is coupled with the output end solid-core optical fiber, and the output end solid-core optical fiber is provided with a filtering output device. The input end of the hollow-core optical fiber 3 is connected with the solid-core output tail fiber of the wavelength division multiplexer 8 in a fusion mode, and the input end fusion point 2 is formed at the coupling connection position.
The output end of the hollow-core optical fiber 3 is connected with the input end of the solid-core single-mode optical fiber provided with the filtering output device in a fusion welding mode, and the coupling connection position forms an output end fusion point 4. This achieves the sealing of the gas inside the hollow-core optical fiber. The synthesized pump laser and seed light enter the hollow-core optical fiber, and generate stimulated Raman scattering effect with the Raman gain gas filled in the hollow-core optical fiber, and then the seed laser is amplified in the process of transmission in the hollow-core optical fiber 3. The amplified Raman laser and the amplified residual pump laser enter the filtering output device through the output end welding point 4 and are output. The filtering output device is used for filtering residual pump light and outputting 2-micrometer-waveband Raman laser. Wherein, the residual pump laser is coupled to the cladding for transmission through the long-period fiber grating 5 and then filtered by the cladding light filter 6; the raman laser light is directly output through the long period fiber grating 5 and the cladding light filter 6.
The 2 μm and 2 μm wavelength bands mentioned above mean that both laser light in the vicinity of the wavelength point can be output. The working wavelength of the 1.9 mu m waveband optical fiber laser pumping source and the 2 mu m waveband seed source is set, so that the laser output with the specific wavelength in the 2 mu m waveband range can be realized.
Above only the utility model discloses an it is preferred embodiment, the utility model discloses a scope of protection not only limits in above-mentioned embodiment, and the all belongs to the utility model discloses a technical scheme under the thinking all belongs to the utility model discloses a scope of protection. It should be noted that, for those skilled in the art, a plurality of modifications and decorations without departing from the principle of the present invention should be considered as the protection scope of the present invention.
Claims (10)
1. Tunable near-infrared all-fiber structure gas Raman laser, which is characterized in that: the output end of the hollow optical fiber is coupled with the output end solid optical fiber, and the output end solid optical fiber is provided with a filtering output device.
2. The tunable near-infrared all-fiber structured gas raman laser according to claim 1, wherein: the pumping source is a 1-micron wave band optical fiber laser or an optical fiber amplifier; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman gain gas is methane, and the hollow-core optical fiber adopts a node-free or connected anti-resonance hollow-core optical fiber.
3. The tunable near-infrared all-fiber structured gas raman laser according to claim 1, wherein: the pumping source is a fiber laser or a fiber amplifier with a wave band of 1.55 mu m; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman gain gas is H2Or D2And the hollow-core optical fiber adopts a hollow-core photonic crystal fiber.
4. The tunable near-infrared all-fiber structured gas raman laser according to claim 1, wherein: the pumping source is a fiber laser or a fiber amplifier with a wave band of 1.9 mu m; the pumping source is in pulse output or continuous output, and the pumping wavelength is tunable; the Raman-enhanced gas is D2And the hollow-core optical fiber adopts a hollow-core photonic crystal fiber.
5. The tunable near-infrared all-fiber structured gas Raman laser according to any one of claims 1-4, wherein: the filtering output device comprises a long-period fiber grating with the central wavelength being the pumping wavelength and a cladding light filter.
6. Tunable near-infrared all-fiber structure gas Raman laser, which is characterized in that: the optical fiber laser device comprises a pumping source, a seed source, a wavelength division multiplexer, a hollow optical fiber and a filtering output device, wherein a solid output tail fiber of the pumping source is connected with the wavelength division multiplexer; the solid output tail fiber of the wavelength division multiplexer is coupled with the hollow fiber, Raman gain gas is filled in the fiber core of the hollow fiber, the hollow fiber provides an environment for long-range interaction of pump laser, seed light and working gas, the output end of the hollow fiber is coupled with the output end solid fiber, and the output end solid fiber is provided with a filtering output device.
7. The tunable near-infrared all-fiber structured gas raman laser according to claim 6, wherein: the pumping source is a continuous fiber laser or a fiber amplifier with a wave band of 1 micron; the seed source is a continuous semiconductor laser with a wave band of 1.5 mu m; the Raman gain gas is methane, and the hollow-core optical fiber adopts a node-free or connected anti-resonance hollow-core optical fiber.
8. The tunable near-infrared all-fiber structured gas raman laser according to claim 6, wherein: the pumping source is a continuous fiber laser or a fiber amplifier with a wave band of 1.55 mu m; the seed source is a continuous semiconductor laser with a wave band of 1.7 mu m; the Raman gain gas is H2Or D2And the hollow-core optical fiber adopts a hollow-core photonic crystal fiber.
9. The tunable near-infrared all-fiber structured gas raman laser according to claim 6, wherein: the pumping source is a continuous fiber laser or a fiber amplifier with a wave band of 1.9 mu m; the seed source is a continuous semiconductor laser with a wave band of 2 mu m; the Raman-enhanced gas is D2And the hollow-core optical fiber adopts a hollow-core photonic crystal fiber.
10. The tunable near-infrared all-fiber structured gas raman laser according to any one of claims 6 to 9, wherein: the filtering output device comprises a long-period fiber grating with the central wavelength being the pumping wavelength and a cladding light filter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021518248.4U CN212935130U (en) | 2020-07-28 | 2020-07-28 | Tunable near-infrared all-fiber structure gas Raman laser |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021518248.4U CN212935130U (en) | 2020-07-28 | 2020-07-28 | Tunable near-infrared all-fiber structure gas Raman laser |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212935130U true CN212935130U (en) | 2021-04-09 |
Family
ID=75332575
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021518248.4U Active CN212935130U (en) | 2020-07-28 | 2020-07-28 | Tunable near-infrared all-fiber structure gas Raman laser |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212935130U (en) |
-
2020
- 2020-07-28 CN CN202021518248.4U patent/CN212935130U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4750201B2 (en) | High-power optical pulse generator and method | |
| KR101804878B1 (en) | A device for increasing the spectral bandwidth of optical pulses as well as an arrangement and a method for reducing the duration of optical pulses with the use of such a device | |
| CN105356209B (en) | For producing the optical fibre gas laser generating means of 1.5 μm laser | |
| CN107275917A (en) | Infrared super continuum source in ultra wide band all -fiber | |
| CN103337779B (en) | The middle infrared-gas laser of pumped fiber | |
| CN102967981A (en) | Super-continuous spectrum light source based on multicore photonic crystal fiber | |
| CN103311782B (en) | Based on blue laser production method and the device of thulium-doped fiber laser quadruple | |
| CN108767637A (en) | THz high repetition frequency high power femto second optical fiber lasers based on dispersive wave | |
| CN109713562B (en) | Random fiber laser based on random Brillouin dynamic grating | |
| CN112600061A (en) | Tunable Raman fiber laser | |
| CN111404005A (en) | All-fiber mode-locked fiber laser | |
| CN114512884B (en) | Method for outputting high-order mode in graded-index optical fiber | |
| CN202995205U (en) | Multicore photonic crystal fiber based supercontinuum source | |
| US9684223B2 (en) | High efficiency fiber optical parametric oscillator | |
| CN108879302B (en) | Optical frequency comb generator based on optical parametric oscillation | |
| CN212935130U (en) | Tunable near-infrared all-fiber structure gas Raman laser | |
| CN110165530A (en) | High-power Raman fiber laser generation method and system | |
| CN212485787U (en) | Near infrared fiber gas Raman laser oscillator | |
| CN111864521A (en) | All-fiber sodium guide star laser generation device | |
| CN212485788U (en) | Mid-infrared fiber gas Raman laser oscillator | |
| CN110416865A (en) | A kind of multicore RE-doped superwide band light comb light source | |
| CN212485786U (en) | Tunable mid-infrared all-fiber structure gas Raman laser | |
| CN110995342A (en) | Water mist space laser communication device based on 1.7 mu m waveband modulation light source | |
| CN212626508U (en) | 3-micron optical fiber gas laser with all-optical fiber structure | |
| CN211265955U (en) | Adjustable ultra-high repetition frequency ultra-short pulse fiber laser |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |