Optical amplifier with large gain bandwidth

Abstract

The invention relates to the technical field of optical communication, and discloses an optical amplifier with a large gain bandwidth, the optical amplifier comprises a first wavelength beam splitting assembly, a gain chip set and a second wavelength beam splitting assembly, input light is divided into a first transmission light path and a second transmission light path through the first wavelength beam splitting assembly, and after being amplified by the gain chip set, the input light is transmitted to the second transmission light path through the second wavelength beam splitting assembly. The first transmission light path and the second transmission light path are recombined into one light beam to be output through a second wavelength beam splitting assembly; according to the light amplification method, a wavelength beam splitting assembly is adopted to distribute an incident light signal to a proper gain medium according to the wavelength, and light in a transmission light path is amplified through the gain medium. According to the optical amplifier, the light in a large wavelength range is distributed to the multiple gain media to be amplified respectively, the gain balance of the optical amplifier in the large wavelength range is improved, the amplified light is adjusted into one beam of output light through the wavelength beam splitting assembly again, and the light amplification effect is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, specifically to a high-gain bandwidth optical amplifier. Background Technology

[0002] Current optical amplifiers are generally semiconductor optical amplifiers, which are devices that use semiconductor materials to amplify optical signals and are widely used in optical communication and optical processing. Their working principle is similar to that of laser diodes, but the difference is that they do not generate new light; instead, they amplify the input optical signal through stimulated emission. Semiconductor optical amplifiers can achieve highly efficient optical signal amplification through miniaturization and integration. They are characterized by small size, wide bandwidth, and high gain.

[0003] In existing semiconductor optical amplifiers, the gain is not perfectly uniform within its gain bandwidth. The gain is typically higher near the center wavelength and lower at the edges of the bandwidth. If the wavelength range of the input optical signal (e.g., multiple channels in a wavelength division multiplexing signal) exceeds the flat gain range of the semiconductor optical amplifier, different wavelengths will experience different gains. This leads to gain non-uniformity, resulting in some wavelengths being amplified more while others are amplified less. This gain non-uniformity affects system performance and reduces the amplification effect. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a high-gain bandwidth optical amplifier, which solves the problem that in existing optical amplifiers, optical signals of different wavelengths experience different gains, leading to gain non-uniformity. This gain non-uniformity affects system performance and reduces the optical amplification effect.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: a high-gain bandwidth optical amplifier, comprising a first wavelength beam splitter, a gain medium group, and a second wavelength beam splitter, wherein the optical path is divided into a first transmission optical path and a second transmission optical path in the wavelength beam splitter;

[0006] The first wavelength beam splitter is provided with a first port, a second port and a third port. The first port is used to receive incident light, the second port is used to output one of the two incident light beams after wavelength selection and transmit the light to the gain medium group; the third port is used to output the other of the two incident light beams after wavelength selection and transmit the light to the gain medium group.

[0007] The second wavelength beam splitter is provided with a fourth port, a fifth port, and a sixth port. The fourth port is used to receive one of the two incident light beams after being amplified by the gain medium group; the fifth port is used to receive the other of the two incident light beams after being amplified by the gain medium group; and the sixth port is used to output the two amplified and combined light beams.

[0008] The gain medium group includes a first gain medium and a second gain medium. The first gain medium is used to receive the light transmitted from the second port, and after gaining, transmit the light to the fourth port. The second gain medium is used to receive the light transmitted from the third port, and after gaining, transmit the light to the fifth port.

[0009] The second port, third port, first gain medium, second gain medium, fourth port, and fifth port of the first wavelength beam splitter are combined to form a parallel optical path.

[0010] In one embodiment of the present invention, the two wavelength-selected beams of light output by the first wavelength beam splitter are arranged as follows: one beam enters the parallel optical path from the second port, is amplified, and then enters the second wavelength beam splitter from the fourth port; the other beam enters the parallel optical path from the third port, is amplified, and then enters the second wavelength beam splitter from the fifth port.

[0011] In one embodiment of the present invention, lenses are provided on both the first and second transmission optical paths, and the lenses are distributed at both ends of the first gain medium and the second gain medium.

[0012] In one embodiment of the present invention, the first wavelength beam splitting component is composed of a parallelogram glass block, a first filter, and a second filter, wherein the parallelogram glass block is coated with an anti-reflection film and a high-reflection film.

[0013] The second wavelength beam splitter is a mirror image of the first wavelength beam splitter.

[0014] In one embodiment of the present invention, the first wavelength beam splitter is used to split the input light into two beams according to the wavelength, output one beam from the second port and enter the first transmission optical path, and output the other beam from the third port and enter the second transmission optical path; the light in the first transmission optical path is amplified by the first gain medium, and the light in the second transmission optical path is amplified by the second gain medium.

[0015] The parallelogram glass block in the first wavelength beam splitter has an angle of α, the refraction angle of the beam entering the parallelogram glass block is β, the distance between the two beams output through the second port and the third port is d, the distance between the hypotenuses of the parallelogram glass block is s, the refractive index of the optical path transmission medium is n1, and the refractive indices of the parallelogram glass block, the first filter, and the second filter are n2. For the dimensions and angle of the parallelogram glass block, the following equations must all hold:

[0016] (1)

[0017] (2)

[0018] In one embodiment of the present invention, the characteristic is that: the incident light wavelength range is set to [λ]. min , λ max The transmittance of the light beam from the first port to the second port corresponding to the wavelength is H1(λ), ​​the transmittance of the light beam from the first port to the third port corresponding to the wavelength is H2(λ), the transmittance of the light beam from the fourth port to the sixth port corresponding to the wavelength is H1(λ), ​​the transmittance of the light beam from the fifth port to the sixth port corresponding to the wavelength is H2(λ), the gain of the first gain medium corresponding to the wavelength is G1(λ), ​​the gain of the second gain medium corresponding to the wavelength is G1(λ), ​​and the optical power of the incident light corresponding to the wavelength is P. in (λ), the optical power after passing through the second port is P1(λ), ​​the optical power after passing through the third port is P2(λ), and the optical power after passing through the first gain medium is P g1 (λ), the optical power after passing through the second gain medium is P g2 (λ), the optical power of the first optical beam after passing through the second wavelength beam splitter is P. out1 (λ), the optical power of the second optical beam after passing through the second wavelength beam splitter is P. out2 (λ), the total optical power after the input light passes through the optical amplifier is P. out (λ), the gain corresponding to the wavelength is G total (λ).

[0019] The optical amplifier amplifies the input light by distributing it to different gain media according to wavelength through a wavelength-splitting component, achieving more uniform gain across different wavelengths and ensuring that the following equations hold true:

[0020] (1)P out1 (λ)=P in (λ)·G1(λ)·H1(λ) 2

[0021] (2)P out2 (λ)=P in (λ)·G2(λ)·H2(λ) 2

[0022] (3)P out (λ)=P out1 (λ)+P out2 (λ)=P in (λ)·(G1(λ)·H1(λ) 2 +G2(λ)·H2(λ) 2 )

[0023] (4)

[0024] (5)G total (λ1)-G total (λ2)≈0,λ1∈[λ min ,λ max ],λ2∈[λ min ,λ max ].

[0025] This invention provides an optical amplifier with high gain and bandwidth. It has the following advantages:

[0026] 1. This invention improves the gain balance of the optical amplifier in a larger wavelength range by distributing light in a wide wavelength range to multiple gain media for amplification. The amplified light is then adjusted into a single output beam by the wavelength beam splitter, effectively improving the amplification effect of the light.

[0027] 2. This invention can provide dual heat dissipation for the optical amplifier through a liquid cooling mechanism and an air cooling mechanism. At the same time, it can also dissipate heat from the liquid in the water tank using the heat dissipation mechanism, thereby preventing the liquid temperature in the water tank from rising due to heat conduction. Therefore, it can improve the heat dissipation effect of the optical amplifier. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the optical amplifier of the present invention.

[0029] Figure 2 This is a line graph showing the insertion loss of the filter in this invention.

[0030] Figure 3 This is a line graph showing the transmittance of the filter in this invention.

[0031] Figure 4 The gain curve of the gain medium of this invention Figure 1 ;

[0032] Figure 5 The gain curve of the gain medium of this invention Figure 2 ;

[0033] Figure 6 This is a graph showing the total gain of the present invention;

[0034] Figure 7 This is a perspective view of the optical amplifier and its package in Embodiment 1 of the present invention.

[0035] Figure 8 This is a schematic diagram of the optical amplifier packaging and mounting tube in Embodiment 1 of the present invention;

[0036] Figure 9This is a schematic diagram of the heat sink fins of the optical amplifier package in Embodiment 1 of the present invention;

[0037] Figure 10 This is a schematic diagram of the optical amplifier packaging mounting bracket in Embodiment 1 of the present invention;

[0038] Figure 11 This is a schematic diagram of the structure of the optical amplifier packaging protective shell in Embodiment 1 of the present invention;

[0039] Figure 12 This is a schematic diagram of the internal structure of the optical amplifier packaging and fixing box in Embodiment 1 of the present invention;

[0040] Figure 13 This is a schematic diagram of the rotating wheel of the optical amplifier package in Embodiment 1 of the present invention;

[0041] Figure 14 This is a schematic diagram of the enlargement mechanism in Embodiment 2 of the present invention;

[0042] Figure 15 This is a schematic diagram of the amplification mechanism in Embodiment 3 of the present invention.

[0043] The components include: 1. First wavelength beam splitter assembly; 2. Second wavelength beam splitter assembly; 3. Gain medium group; 4. First port; 5. Second port; 6. Third port; 7. Fourth port; 8. Fifth port; 9. Sixth port; 10. First gain medium; 11. Second gain medium; 12. Lens; 13. Parallelogram glass block; 14. First filter; 15. Second filter; 16. Anti-reflection film; 17. High-reflection film; 18. Optical amplifier; 19. Housing; 20. Top plate; 21. Liquid cooling mechanism; 21. 01. Water pump; 2102. Liquid cooling pipe; 2103. Water inlet pipe; 2104. Water tank; 22. Air cooling mechanism; 2201. Mounting pipe; 2202. Mounting bracket; 2203. Rotating shaft; 2204. Fan; 2205. Fixing box; 2206. Impeller; 2207. Water inlet pipe; 2208. Stabilizer; 2209. Protective shell; 2210. Filter plate; 23. Heat dissipation mechanism; 2301. Rotating rod; 2302. Rotating wheel; 2303. Stirring blade; 2304. Heat dissipation fins. Detailed Implementation

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Example 1, please refer to the appendix. Figure 1 - Appendix Figure 13 The present invention provides a high-gain bandwidth optical amplifier and its package. The optical amplifier 18 includes a first wavelength beam splitter 1, a gain medium group 2, and a second wavelength beam splitter 3. The optical path is divided into a first transmission optical path and a second transmission optical path in the wavelength beam splitter.

[0046] The first wavelength beam splitter 1 is provided with a first port 4, a second port 5, and a third port 6. The first port 4 is used to receive incident light, the second port 5 is used to output one of the two incident light beams after wavelength selection and transmit the light to the gain medium group 2; the third port 6 is used to output the other of the two incident light beams after wavelength selection and transmit the light to the gain medium group 2.

[0047] The second wavelength beam splitter 3 is provided with a fourth port 7, a fifth port 8, and a sixth port 9. The fourth port 7 is used to receive one of the two incident light beams after being amplified by the gain medium group; the fifth port 8 is used to receive the other of the two incident light beams after being amplified by the gain medium group; and the sixth port 9 is used to output the two amplified and combined light beams.

[0048] The gain medium group 2 is provided with a first gain medium 10 and a second gain medium 11. The first gain medium 10 is used to receive the light transmitted from the second port 5 and transmit the light to the fourth port 7 after gaining. The second gain medium 11 is used to receive the light transmitted from the third port 6 and transmit the light to the fifth port 8 after gaining.

[0049] The second port 5 and the third port 6 of the first wavelength beam splitter, the first gain medium 10 and the second gain medium 11, and the fourth port 7 and the fifth port 8 of the second wavelength beam splitter combine to form a parallel optical path.

[0050] The first wavelength beam splitter 1 outputs two wavelength-selected beams of light. One beam enters the parallel optical path from the second port 5, is amplified, and then enters the second wavelength beam splitter 3 from the fourth port 7. The other beam enters the parallel optical path from the third port 6, is amplified, and then enters the second wavelength beam splitter 3 from the fifth port 8. Lenses 12 are provided on both the first and second transmission optical paths, and the lenses 12 are distributed at both ends of the first gain medium 10 and the second gain medium 11. The first wavelength beam splitter 1 is composed of a parallelogram glass block 13, a first filter 14, and a second filter 15. The parallelogram glass block is coated with an anti-reflection film 16 and a high-reflection film 17. The second wavelength beam splitter 3 is a mirror image of the first wavelength beam splitter 1.

[0051] The first wavelength beam splitter 1 is used to split the input light into two beams according to the wavelength. One beam is output from the second port 5 and enters the first transmission optical path, and the other beam is output from the third port 6 and enters the second transmission optical path. The light in the first transmission optical path is amplified by the first gain medium 10, and the light in the second transmission optical path is amplified by the second gain medium 11.

[0052] The parallelogram glass block 13 in the first wavelength beam splitter assembly 1 has an angle of α, the refraction angle of the beam entering the parallelogram glass block 13 is β, the distance between the two beams output through the second port 5 and the third port 6 is d, the distance between the hypotenuses of the parallelogram glass block 13 is s, the refractive index of the optical path transmission medium is n1, and the refractive indices of the parallelogram glass block 13, the first filter 14, and the second filter 15 are n2. For the dimensions and angle of the parallelogram glass block 13, the following equations must all hold:

[0053] (1)

[0054] (2)

[0055] The incident light wavelength range is set to [λ]. min , λ max The transmittance of the light beam from port 4 to port 5 corresponding to the wavelength is H1(λ), ​​the transmittance of the light beam from port 4 to port 6 corresponding to the wavelength is H2(λ), the transmittance of the light beam from port 7 to port 9 corresponding to the wavelength is H1(λ), ​​the transmittance of the light beam from port 8 to port 9 corresponding to the wavelength is H2(λ), the gain of the first gain medium 10 corresponding to the wavelength is G1(λ), ​​the gain of the second gain medium 11 corresponding to the wavelength is G1(λ), ​​and the optical power of the incident light corresponding to the wavelength is P. in (λ), the optical power after passing through the second port 5 is P1(λ), ​​the optical power after passing through the third port 6 is P2(λ), and the optical power after passing through the first gain medium 10 is P g1 (λ), the optical power after passing through the second gain medium 11 is P. g2 (λ), the optical power of the first optical beam after passing through the second wavelength beam splitter 3 is P. out1 (λ), the optical power of the second optical beam after passing through the second wavelength beam splitter 3 is P. out2 (λ), the total optical power after the input light passes through the optical amplifier is P. out (λ), the gain corresponding to the wavelength is G total (λ);

[0056] An optical amplifier amplifies input light by distributing it according to wavelength to different gain media through a wavelength-splitting components, achieving more uniform gain across different wavelengths and ensuring that the following equations hold true:

[0057] (1)P out1 (λ)=P in (λ)·G1(λ)·H1(λ) 2

[0058] (2)P out2 (λ)=P in (λ)·G2(λ)·H2(λ) 2

[0059] (3)P out (λ)=P out1 (λ)+P out2 (λ)=P in (λ)·(G1(λ)·H1(λ) 2 +G2(λ)·H2(λ) 2 )

[0060] (4)

[0061] (5)G total (λ1)-G total (λ2)≈0,λ1∈[λ min ,λ max ],λ2∈[λ min ,λ max ]

[0062] The wavelength beam splitter divides the incident light into a first transmission optical path and a second transmission optical path. Lenses 12 are provided on both the first and second transmission optical paths, and the lenses 12 are distributed at both ends of each gain medium of the gain medium group 2.

[0063] The wavelength beam splitter consists of a parallelogram glass block 13 and two filters. The parallelogram glass block 13 has a 76.5° angle and a distance of 2.453 mm between the two angled sides. An anti-reflection film 16 and a high-reflection film 17 are coated on the parallelogram glass block 13. The passband wavelengths of the two filters are [1520nm, 1550nm] and [1550nm, 1580nm], respectively. After passing through the two filters, the distance between the two transmission optical paths is 0.75 mm.

[0064] The incident light enters from the first port 4 at an incident angle of 13.5° and passes through the first filter 14. Light with wavelengths in the range of [1520nm, 1550nm] passes through the first filter 14 and enters the first transmission optical path. Light with wavelengths in the range of [1520nm, 1550nm] is reflected into the second transmission optical path. After passing through the high-reflectivity film 17 region of the parallelogram glass block 13, it is reflected towards the second filter 15. Light with wavelengths in the range of [1550nm, 1580nm] passes through the second filter 15.

[0065] Gain medium group 2 consists of two semiconductor optical amplifier chips. The first gain medium 10 can effectively amplify light in the wavelength range of [1520nm, 1550nm], and the second gain medium 611 can effectively amplify light in the wavelength range of [1550nm, 1580nm].

[0066] After passing through the first wavelength beam splitter 1, the two beams of light are coupled into the first gain medium 10 and the second gain medium 11 respectively through the lens 12 for amplification. The amplified light is then coupled into two collimated beams through the lens 12 and enters another flipped second wavelength beam splitter 3 to be combined into one beam of light.

[0067] See Figures 2-3 The transmittance of the first and second filters is approximately:

[0068]

[0069] Wherein: H i,max The maximum transmittance of the i-th filter;

[0070] λ i,0 The center wavelength of the i-th filter;

[0071] Δλ i Let be the bandwidth of the i-th filter.

[0072] See Figure 4-5 The gain curve of the gain medium is approximately as follows:

[0073]

[0074] Among them: G i,0 The maximum gain of the i-th gain medium;

[0075] λ ci The center wavelength of the i-th gain medium;

[0076] Δλ i Let be the gain half-width of the i-th gain medium.

[0077] After (1), the power of each beam is:

[0078]

[0079] P i The power of the i-th band beam after relevant processing;

[0080] P in The power of the incident light signal;

[0081] ∑ j＝1 n H j(λ): The transmittance function H of filters from the 1st to the nth filter. j (λ) Summation.

[0082] The power of each beam after gaining through the gain medium is:

[0083] P out,i =P i ·G i (λ).

[0084] The power of each beam after being combined by the wavelength beam splitter is:

[0085] P out,i =P i ·G i (λ)·H i (λ).

[0086] The total output power is:

[0087]

[0088] See Figure 6 Then the total gain of this amplifier is:

[0089]

[0090] In the wavelength range of 1520–1580 nm, if gain media 1 and 2 are used alone to amplify the signal, the gain flatness is 2.37 dB and 2.675 dB, respectively. However, by using the method of this invention, after amplification with both gain media, the gain flatness is 0.43 dB.

[0091] Its external package includes a housing 19, a top plate 20 is detachably connected to the top of the housing 19, a liquid cooling mechanism 21 is fixedly connected to the top of the top plate 20, the liquid cooling mechanism 21 is used for heat dissipation of liquid, an air cooling mechanism 22 is provided inside the liquid cooling mechanism 21, the air cooling mechanism 22 is used for air cooling of optical amplifier 18, a heat dissipation mechanism 23 is provided inside the liquid cooling mechanism 21, the heat dissipation mechanism 23 can dissipate heat for the liquid inside the liquid cooling mechanism 21, and an optical amplifier 18 is fixedly connected inside the housing 19.

[0092] The liquid cooling mechanism 21 includes a water pump 2101, which provides the power for liquid flow. The water pump 2101 is externally fixedly connected to the outside of the housing 19. A liquid cooling pipe 2102 is fixedly connected to the output end of the water pump 2101. The liquid cooling pipe 2102 can be wound around the outside of the optical amplifier 18 to provide water cooling. A water inlet pipe 2103 is fixedly connected to the input end of the water pump 2101. A water tank 2104 is fixedly connected to the top of the top plate 20. The water inlet pipe 2103 can easily draw in liquid from inside the water tank 2104. The liquid cooling pipe 2102 is wound around the optical amplifier 18. Externally, the water inlet pipe 2103 penetrates the outside of the water tank 2104. When the optical amplifier 18 operates for a long time, the water pump 2101 is started. After the water pump 2101 is started, it can draw out the liquid inside the water tank 2104 through the water inlet pipe 2103 and pass the liquid into the liquid cooling pipe 2102 through the output end of the water pump 2101. Since the liquid cooling pipe 2102 is wrapped around the outside of the optical amplifier 18, the heat of the optical amplifier 18 can be conducted into the liquid inside the liquid cooling pipe 2102 through heat conduction, and then passed into the water tank 2104 along with the liquid cooling pipe 2102.

[0093] The air-cooling mechanism 22 includes two mounting pipes 2201, which provide mounting positions. Both mounting pipes 2201 are externally fixedly connected to the top interior of the water tank 2104. A mounting bracket 2202 is fixedly connected to the bottom inner side of each mounting pipe 2201, providing the mounting position. A rotating shaft 2203 is rotatably connected to the middle of the mounting bracket 2202, providing the mounting position. A fan 2204 is rotatably fixedly connected to the bottom outer end of the rotating shaft 2203. When the rotating shaft 2203 rotates, it drives the fan 2204 to rotate, thereby generating airflow. A mounting box 2205 is rotatably connected to the outside of one of the rotating shafts 2203. 5. An installation location is provided. An impeller 2206 is rotatably connected inside the mounting box 2205. The impeller 2206 can rotate when liquid is flowing. A water inlet pipe 2207 is fixedly connected to the outside of the mounting box 2205. The water inlet pipe 2207 can introduce liquid from the water tank 2104 into the interior of the mounting box 2205. A stabilizer 2208 is fixedly connected to the middle of the mounting pipe 2201. The stabilizer 2208 can provide rotational stability for the rotating shaft 2203. The bottom of the mounting box 2205 is fixedly connected to the top of one of the stabilizers 2208. A protective shell 2209 is fixedly connected between the two mounting pipes 2201. A belt is sleeved between the tops of the two rotating shafts 2203. The protective shell 2209 can prevent... The protective belt prevents liquid from the water tank 2104 from entering the mounting pipe 2201. The belt is located inside the protective shell 2209. The middle part of the rotating shaft 2203 is rotatably connected to the middle part of the stabilizer 2208. The fan 2204 is located inside the mounting pipe 2201. A filter plate 2210 is fixedly connected to the inner side of the top end of the mounting pipe 2201. The mounting pipe 2201 can filter impurities in the air. The bottom of the mounting pipe 2201 penetrates the interior of the top plate 20. The tops of the two rotating shafts 2203 are rotatably connected to the two ends of the protective shell 2209, respectively. When the water pump 2101 draws liquid through the input end and the inlet pipe 2103, the liquid can enter the fixed box 2205 through the inlet pipe 2207. Inside the liquid, the impeller 2206 is rotated by the flow of liquid. The rotation of the impeller 2206 drives one of the rotating shafts 2203 to rotate, which in turn drives the fan 2204 to rotate. The fan 2204 generates airflow, which is directed to the optical amplifier 18 for air cooling. The water tank 2104 also cools the airflow entering the mounting pipe 2201. Furthermore, the rotation of one rotating shaft 2203 drives another rotating shaft 2203 via a belt, which in turn drives the other fan 2204 to rotate, allowing both fans 2204 to perform air cooling.

[0094] The heat dissipation mechanism 23 includes a rotating rod 2301, which provides installation conditions. The bottom of the rotating rod 2301 is rotatably connected to the top of the top plate 20. A rotating wheel 2302 is fixedly connected to the outer bottom end of the rotating rod 2301. The rotating wheel 2302 can rotate when the liquid cooling pipe 2102 drains water, thereby driving the rotating rod 2301 to rotate. An agitator 2303 is fixedly connected to the outer middle end of the rotating rod 2301. The agitator 2303 can rotate under the rotation of the rotating rod 2301. Multiple heat dissipation fins 2304 are fixedly connected to the outside of the water tank 2104. The heat dissipation fins 2304 can assist the liquid inside the water tank 2104 in heat conduction and dissipation. The top of the rotating rod 2301 is rotatably connected to the top of the inside of the water tank 2104. The end of the liquid cooling pipe 2102 away from the water pump 2101 is located outside the rotating wheel 2302. When the liquid cooling pipe 2102 re-enters the water tank 2104, it drives the rotating wheel 2302 to rotate. The rotation of the rotating wheel 2302 drives the rotating rod 2301 to rotate. When the rotating rod 2301 rotates, it drives the stirring blade 2303 to rotate. The rotation of the stirring blade 2303 stirs the liquid inside the water tank 2104, thereby accelerating the heat dissipation of the liquid inside the water tank 2104 and keeping the liquid inside the water tank 2104 at a lower temperature.

[0095] Working principle: When the optical amplifier 18 operates for a long time, the water pump 2101 is started. After the water pump 2101 is started, it can draw out the liquid inside the water tank 2104 through the water inlet pipe 2103, and pass the liquid into the liquid cooling pipe 2102 through the output end of the water pump 2101. Since the liquid cooling pipe 2102 is wrapped around the outside of the optical amplifier 18, the heat of the optical amplifier 18 can be conducted into the liquid inside the liquid cooling pipe 2102 through heat conduction, and then passed into the water tank 2104 along with the liquid cooling pipe 2102.

[0096] When the water pump 2101 draws liquid through the input end and the inlet pipe 2103, the liquid can enter the interior of the fixed box 2205 through the inlet pipe 2207. Then, the flow of the liquid can drive the impeller 2206 to rotate. After the impeller 2206 rotates, it can drive one of the rotating shafts 2203 to rotate. Then, the rotating shaft 2203 drives the fan 2204 to rotate. Then, the fan 2204 generates air force, which is delivered to the optical amplifier 18 to achieve air cooling. The water tank 2104 can also cool the airflow entering the mounting pipe 2201. After one of the rotating shafts 2203 rotates, it can drive another rotating shaft 2203 to rotate through the belt. Then, it can drive another fan 2204 to rotate, so that both fans 2204 can perform air cooling.

[0097] When the liquid cooling pipe 2102 re-enters the interior of the water tank 2104, it drives the rotating wheel 2302 to rotate. The rotating wheel 2302 then drives the rotating rod 2301 to rotate. When the rotating rod 2301 rotates, it drives the stirring blade 2303 to rotate. The stirring blade 2303 then stirs the liquid inside the water tank 2104, thereby accelerating the heat dissipation of the liquid inside the water tank 2104 and keeping the liquid inside the water tank 2104 at a lower temperature.

[0098] A light signal with a wide wavelength range enters the first wavelength beam splitter 1. When it passes through the first filter 14, the first filter 14 splits the light based on wavelength. Part of the light passes through the first filter 14, and part of the light is reflected by the first filter 14. At the same time, it is reflected by the reflective film 17 and transmitted through the second filter 15. The two collimated beams with larger diameters separated by the first wavelength beam splitter 1 are converged to the light input end of the gain medium group 02 through the lens 12. After being amplified, the two light signals are emitted from the light output end and converged into two collimated light signals through the lens 12. The two collimated light signals are then recombined into one light signal through another flipped second wavelength beam splitter 3, realizing the amplification of the light signal with a wide wavelength range.

[0099] Example 2, please refer to the appendix. Figure 14 Based on Example 1, the filter of the second wavelength beam splitter 3 is replaced and the installation direction is changed so that the optical path of the first transmission optical path is the same as that of the second transmission optical path, thereby reducing the phase difference of different wavelength optical signals.

[0100] It includes a first wavelength beam splitter 1, a gain medium group 2, and a second wavelength beam splitter 3. The optical path is divided into a first transmission optical path and a second transmission optical path in the wavelength beam splitter.

[0101] The first wavelength beam splitter 1 is provided with a first port 4, a second port 5, and a third port 6. The first port 4 is used to receive incident light, the second port 5 is used to output one of the two incident light beams after wavelength selection and transmit the light to the gain medium group 2; the third port 6 is used to output the other of the two incident light beams after wavelength selection and transmit the light to the gain medium group 2.

[0102] The first wavelength beam splitter 1 consists of a parallelogram glass block 12, a first filter 13, and a second filter 14. The parallelogram glass block 12 is coated with an anti-reflection film 15 and a high-reflection film 16. The passband wavelength of the first filter 13 is [1520nm, 1550nm], and the passband wavelength of the second filter 14 is [1550nm, 1580nm]. The input light enters the first wavelength beam splitter 1 from the first port 4. The light in the wavelength range of [1520nm, 1550nm] passes through the first filter 13 and is output from the second port 5. The light in the wavelength range of [1550nm, 1580nm] is reflected by the first filter 13, reflected again by the high-reflection film 16, and then passes through the second filter 14 and is output from the third port 6.

[0103] The second wavelength beam splitter 3 is provided with a fourth port 7, a fifth port 8, and a sixth port 9. The fourth port 7 is used to receive one of the two incident light beams after being amplified by the gain medium group; the fifth port 8 is used to receive the other of the two incident light beams after being amplified by the gain medium group; and the sixth port 9 is used to output the two amplified and combined light beams.

[0104] The second wavelength beam splitter 3 consists of a parallelogram glass block 12, a first filter 13, and a second filter 14. The parallelogram glass block 12 is coated with an anti-reflection film 15 and a high-reflection film 16. The first filter 13 has a passband wavelength of [1520nm, 1550nm], and the second filter 14 has a passband wavelength of [1550nm, 1580nm]. Light with a gain in the [1520nm, 1550nm] wavelength range enters the second wavelength beam splitter 3 from the fourth port 7, passes through the first filter 13, is reflected by the high-reflection film 16, and then is reflected by the second filter 14 and output from the sixth port 9. Light with a gain in the [1550nm, 1580nm] wavelength range enters the second wavelength beam splitter 3 from the fifth port 8, passes through the second filter 14, and is combined with the light in the [1520nm, 1550nm] wavelength range and output from the sixth port 9.

[0105] The gain medium group 2 is provided with a first gain medium 10 and a second gain medium 11. The first gain medium 10 is used to receive light in the wavelength range of [1520nm, 1550nm] transmitted from the second port 5, and after gaining, transmits the light to the fourth port 7; the second gain medium 11 is used to receive light in the wavelength range of [1550nm, 1580nm] transmitted from the third port 6, and after gaining, transmits the light to the fifth port 8.

[0106] Each gain medium in gain medium group 2 has a lens 17 on both sides for coupling parallel light into the gain medium or coupling the divergent light amplified by the gain medium into parallel light.

[0107] The second port 5 and the third port 6 of the first wavelength beam splitter 1, the first gain medium 10 and the second gain medium 11, and the fourth port 7 and the fifth port 8 of the second wavelength beam splitter 3 are combined to form a parallel optical path.

[0108] Example 3, please refer to the appendix. Figure 15 Based on Examples 1 and 2, the number of filters in the first wavelength beam splitter and the second wavelength beam splitter is increased to achieve effective gain over a larger wavelength range, or to further improve the gain flatness over the same wavelength range.

[0109] It includes a first wavelength beam splitter 1, a gain medium group 2, and a second wavelength beam splitter 3. The optical path is divided into a first transmission optical path, a second transmission optical path, a third transmission optical path, and a fourth transmission optical path in the wavelength beam splitter.

[0110] The first wavelength beam splitter 1 is provided with a first port 4, a second port 5, a third port 6, a fourth port 7, and a fifth port 8. The first port 4 is used to receive incident light; the second port 5 is used to output one of the four incident light beams after wavelength selection and transmit the light to the gain medium group 3; the third port 6 is used to output the second of the four incident light beams after wavelength selection and transmit the light to the gain medium group 3; the fourth port 7 is used to output the third of the four incident light beams after wavelength selection and transmit the light to the gain medium group 3; and the fifth port 8 is used to output the fourth of the four incident light beams after wavelength selection and transmit the light to the gain medium group 3.

[0111] The first wavelength beam splitter assembly consists of a parallelogram-shaped glass block 9, a first filter 10, a second filter 11, a third filter 12, and a fourth filter 13. The parallelogram-shaped glass block 9 is coated with an anti-reflection film 14 and a high-reflection film 15. The passband wavelength of the first filter 10 is [1261nm, 1280nm], the passband wavelength of the second filter 11 is [1281nm, 1300nm], the passband wavelength of the third filter 12 is [1301nm, 1320nm], and the passband wavelength of the fourth filter 13 is [1321nm, 1340nm]. Input light enters the first wavelength beam splitter assembly 1 from the first port 4, where [1261nm, 1280nm] is the wavelength. Light in the wavelength range passes through the first filter 10 and is output from the second port 5. Light in the wavelength range of [1281nm, 1300nm] is reflected by the first filter 10, reflected again by the high reflectivity film 15, and then passes through the second filter 11 and is output from the third port 6. Light in the wavelength range of [1301nm, 1320nm] is reflected 4 times between the first filter 10, the second filter 11, and the high reflectivity film 15, and then passes through the third filter 12 and is output from the fourth port 7. Light in the wavelength range of [1321nm, 1340nm] is reflected 6 times between the first filter 10, the second filter 11, the third filter 12, and the high reflectivity film 15, and then passes through the fourth filter 13 and is output from the fifth port 8.

[0112] The second wavelength beam splitter 3 is provided with a sixth port 16, a seventh port 17, an eighth port 18, a ninth port 19, and a tenth port 20. The sixth port 16 is used to receive the first beam of the four incident lights after being amplified by the gain medium group 2; the seventh port 17 is used to receive the second beam of the four incident lights after being amplified by the gain medium group 2; the eighth port 18 is used to receive the third beam of the four incident lights after being amplified by the gain medium group 2; the ninth port 19 is used to receive the fourth beam of the four incident lights after being amplified by the gain medium group 2; and the tenth port 20 is used to output the beam of the four beams after being amplified and combined.

[0113] The second wavelength beam splitter 3 consists of a parallelogram-shaped glass block 9, a first filter 10, a second filter 11, a third filter 12, and a fourth filter 13. The parallelogram-shaped glass block 9 is coated with an anti-reflection film 14 and a high-reflection film 15. The passband wavelength of the first filter 10 is [1261nm, 1280nm], the passband wavelength of the second filter 11 is [1281nm, 1300nm], the passband wavelength of the third filter 12 is [1301nm, 1320nm], and the passband wavelength of the fourth filter 13 is [1321nm, 1340nm]. Light in the [1261nm, 1280nm] wavelength range, after gain, enters the second wavelength beam splitter 3 from the sixth port 16 and is reflected 6 times between the high-reflection film 15, the second filter 11, the third filter 12, and the fourth filter 13. The light beam combined with other wavelengths is output from the tenth port 20; the light in the wavelength range of [1281nm, 1300nm] after gain is entered into the second wavelength beam splitter 3 from the seventh port 17, and after being reflected 4 times between the high reflectivity film 15, the third filter 12, and the fourth filter 13, it is combined with other wavelengths and output from the tenth port 20; the light in the wavelength range of [1301nm, 1320nm] after gain is entered into the second wavelength beam splitter 3 from the eighth port 18, and after being reflected by the high reflectivity film 15 and the fourth filter 13, it is combined with other wavelengths and output from the tenth port 20; the light in the wavelength range of [1321nm, 1340nm] after gain is entered into the second wavelength beam splitter 3 from the ninth port 19, and after passing through the fourth filter 13, it is combined with other wavelengths and output from the tenth port 20.

[0114] The gain medium group 2 includes a first gain medium 21, a second gain medium 22, a third gain medium 23, and a fourth gain medium 24. The first gain medium 21 is used to receive light in the wavelength range of [1261nm, 1280nm] transmitted from the second port 5, and after gaining, transmits the light to the sixth port 16. The second gain medium 22 is used to receive light in the wavelength range of [1281nm, 1300nm] transmitted from the third port 6, and after gaining, transmits the light to the seventh port 17. The third gain medium 23 is used to receive light in the wavelength range of [1301nm, 1320nm] transmitted from the fourth port 7, and after gaining, transmits the light to the eighth port 18. The fourth gain medium 24 is used to receive light in the wavelength range of [1321nm, 1340nm] transmitted from the fifth port 8, and after gaining, transmits the light to the ninth port 19.

[0115] Each gain medium in the gain medium group 2 is provided with a lens 25 on both sides, which is used to couple parallel light into the gain medium or to couple the divergent light after the gain medium is amplified into parallel light.

[0116] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-gain, high-bandwidth optical amplifier, characterized in that, It includes a first wavelength beam splitter (1), a gain medium group (2), and a second wavelength beam splitter (3). The optical path is divided into a first transmission optical path and a second transmission optical path in the wavelength beam splitter. The first wavelength beam splitter (1) is provided with a first port (4), a second port (5), and a third port (6). The first port (4) is used to receive incident light, the second port (5) is used to output one of the two incident light beams after wavelength filtering and transmit the light to the gain medium group (2); the third port (6) is used to output the other of the two incident light beams after wavelength filtering and transmit the light to the gain medium group (2). The second wavelength beam splitter (3) is provided with a fourth port (7), a fifth port (8), and a sixth port (9). The fourth port (7) is used to receive one of the two incident beams after being amplified by the gain medium group; the fifth port (8) is used to receive the other of the two incident beams after being amplified by the gain medium group; and the sixth port (9) is used to output the two beams of light after being amplified and combined. The gain medium group (2) is provided with a first gain medium (10) and a second gain medium (11). The first gain medium (10) is used to receive the light transmitted from the second port (5) and transmit the light to the fourth port (7) after gaining. The second gain medium (11) is used to receive the light transmitted from the third port (6) and transmit the light to the fifth port (8) after gaining. The second port (5), the third port (6), the first gain medium (10), the second gain medium (11), the fourth port (7), and the fifth port (8) of the second wavelength beam splitter are combined to form a parallel optical path.

2. The optical amplifier according to claim 1, characterized in that: The first wavelength beam splitter (1) outputs two wavelength-filtered beams of light. One beam enters the parallel optical path from the second port (5), and after being amplified, enters the second wavelength beam splitter (3) from the fourth port (7). The other beam enters the parallel optical path from the third port (6), and after being amplified, enters the second wavelength beam splitter (3) from the fifth port (8).

3. The optical amplifier according to claim 1 is characterized in that: Lenses (12) are provided on both the first and second transmission optical paths, and the lenses (12) are distributed at both ends of the first gain medium (10) and the second gain medium (11).

4. The optical amplifier according to claim 1 is characterized in that: The first wavelength beam splitter (1) is composed of a parallelogram glass block (13), a first filter (14), and a second filter (15). The parallelogram glass block is coated with an anti-reflection film (16) and a high-reflection film (17). The second wavelength beam splitter (3) is a mirror image of the first wavelength beam splitter (1).

5. The optical amplifier according to claim 1 is characterized in that: The first wavelength beam splitter (1) is used to split the input light into two beams according to the wavelength. One beam is output from the second port (5) and enters the first transmission optical path. The other beam is output from the third port (6) and enters the second transmission optical path. The light in the first transmission optical path is amplified by the first gain medium (10), and the light in the second transmission optical path is amplified by the second gain medium (11). The parallelogram glass block (13) in the first wavelength beam splitter assembly (1) has an angle of α, the refraction angle of the beam entering the parallelogram glass block (13) is β, the distance between the two beams output through the second port (5) and the third port (6) is d, the distance between the hypotenuses of the parallelogram glass block (13) is s, the refractive index of the optical path transmission medium is n1, and the refractive indices of the parallelogram glass block (13), the first filter (14), and the second filter (15) are n2. For the dimensions and angle of the parallelogram glass block, the following equations must all hold: (1) (2) 6. The optical amplifier according to claim 1, characterized in that: The incident light wavelength range is set to [λ]. min , λ max The transmittance of the light beam from the first port (4) to the second port (5) corresponding to the wavelength is H1(λ), ​​the transmittance of the light beam from the first port (4) to the third port (6) corresponding to the wavelength is H2(λ), the transmittance of the light beam from the fourth port (7) to the sixth port (9) corresponding to the wavelength is H1(λ), ​​the transmittance of the light beam from the fifth port (8) to the sixth port (9) corresponding to the wavelength is H2(λ), the gain of the first gain medium (10) corresponding to the wavelength is G1(λ), ​​the gain of the second gain medium (11) corresponding to the wavelength is G1(λ), ​​and the optical power of the incident light corresponding to the wavelength is P. in (λ), the optical power after passing through the second port (5) is P1(λ), ​​the optical power after passing through the third port (6) is P2(λ), and the optical power after passing through the first gain medium (10) is P g1 (λ), the optical power after passing through the second gain medium (11) is P g2 (λ), the optical power of the first optical beam after passing through the second wavelength beam splitter (3) is P. out1 (λ), the optical power of the second optical beam after passing through the second wavelength beam splitter (3) is P. out2 (λ), the total optical power after the input light passes through the optical amplifier is P. out (λ), the gain corresponding to the wavelength is G total (λ). The optical amplifier amplifies the input light by distributing it to different gain media according to wavelength through a wavelength-splitting component, achieving more uniform gain across different wavelengths and ensuring that the following equations hold true: (1)P out1 (λ)=P in (λ)·G1(λ)·H1(λ) 2 (2)P out2 (λ)=P in (λ)·G2(λ)·H2(λ) 2 (3)P out (λ)=P out1 (λ)+P out2 (λ)=P in (λ)·(G1(λ)·H1(λ) 2 +G2(λ)·H2(λ) 2 ) (4) (5)G total (λ1)-G total (λ2)≈0,λ1∈[λ min ,l max ],λ2∈[λ min ,l max ]。

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