Optical fiber amplifier structure

Abstract

The utility model relates to an optical fiber amplifier structure which comprises a seed source, a first double-optical-fiber collimator, an isolator, a second double-optical-fiber collimator, a gain optical fiber, a light beam combiner, a pumping source, a passive optical fiber and an optical fiber output head. According to the optical fiber amplifier, a single isolator structure is used for replacing a traditional two-isolator structure, backward light and amplified signal light are isolated, and the number of devices is reduced, so that the size of the optical fiber amplifier is reduced, and the cost of the optical fiber amplifier is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to laser technology field, concretely relates to a kind of optical fiber amplifier structures. BACKGROUND

[0002] The current common MOPA (power amplifier of master oscillator) structure, an optical isolator is placed in the front end of optical fiber amplifier, for isolating the backward light of optical fiber amplifier, to avoid the working state of backward light affecting seed source or the damage of seed source, and another optical isolator is placed in the rear end of optical fiber amplifier, for isolating the light returned from the output end of optical fiber amplifier, to avoid the working state of returned light affecting optical fiber amplifier or the damage of optical fiber amplifier. In turn, multiple optical fiber amplifiers will require multiple optical isolators. For optical fiber amplifier system with volume requirement, the structure of multiple isolators is difficult to reduce volume. SUMMARY

[0003] The utility model aims at overcoming the insufficient of prior art, provide a kind of optical fiber amplifier structure.

[0004] To achieve the above object, the utility model adopts the following technical scheme:

[0005] A kind of optical fiber amplifier structure, including seed source, first double optical fiber collimator, isolator, second double optical fiber collimator, gain optical fiber, light combiner, pump source, passive optical fiber and optical fiber output head;

[0006] The first double optical fiber collimator is composed of first input optical fiber, second input optical fiber, first collimating lens, second collimating lens and first glass sleeve, the first collimating lens and the second collimating lens are located in the first glass sleeve, the first input optical fiber is correspondingly arranged with the first collimating lens, and the second input optical fiber is correspondingly arranged with the second collimating lens;

[0007] The isolator is composed of sequentially arranged first polarization beam splitter, Faraday rotator, half-wave plate and second polarization beam splitter;

[0008] The second double optical fiber collimator is used for receiving collimated signal light, and the second double optical fiber collimator is composed of third input optical fiber, fourth input optical fiber, third collimating lens, fourth collimating lens and second glass sleeve, the third collimating lens and the fourth collimating lens are located in the second glass sleeve, the third input optical fiber is correspondingly arranged with the third collimating lens, and the fourth input optical fiber is correspondingly arranged with the fourth collimating lens;

[0009] The seed source is used for outputting seed signal light;

[0010] The first double optical fiber collimator is used for collimating seed signal light and collimating amplified signal light;

[0011] The isolator is used for passing collimated signal light and amplified signal light in one direction and isolating back-transmitted light;

[0012] The second double-fiber collimator is used for receiving coupled collimated seed signal light and receiving coupled amplified signal light;

[0013] The pump source is used for outputting pump light;

[0014] The light combiner is used for coupling pump light into the gain fiber and coupling amplified signal light into the passive fiber;

[0015] The gain fiber is used for absorbing pump light, generating particle number inversion and amplifying signal light;

[0016] The passive fiber is used for transmitting amplified signal light output by the light combiner into the first double-fiber collimator;

[0017] The fiber output head is used for outputting amplified signal light.

[0018] Further, the light combiner and the pump source constitute forward pumping between the second double-fiber collimator and the gain fiber, or constitute reverse pumping between the gain fiber and the passive fiber, or constitute bidirectional pumping by simultaneously providing the light combiner and the pump source between the gain fiber and the passive fiber.

[0019] Further, the seed source and the pump source are semiconductor lasers, fiber lasers or solid-state lasers.

[0020] Further, the seed source and the pump source are continuous or pulsed in operation.

[0021] Further, the gain ions in the gain fiber include any one or more of neodymium ions, erbium ions, germanium ions, praseodymium ions, holmium ions, europium ions, ytterbium ions, dysprosium ions and thulium ions.

[0022] The above technical scheme has the beneficial effects that a single isolator structure is used to replace the traditional two isolator structures, the backward light and the amplified signal light are isolated, the number of devices is reduced, the volume of the fiber amplifier is reduced, and the cost of the fiber amplifier is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0023] The utility model makes further detailed description in combination with the drawings and specific embodiment:

[0024] Figure 1 It is the schematic view of the fiber amplifier structure of the utility model adopting the backward pumping;

[0025] Figure 2 It is the first double optical fiber collimator structure schematic view of the utility model;

[0026] Figure 3 It is the second double optical fiber collimator structure schematic view of the utility model;

[0027] Figure 4 It is the isolator structure and optical path schematic view of the utility model;

[0028] Figure 5 It is the isolator incidence surface schematic view of the utility model. DETAILED DESCRIPTION

[0029] As Figures 1-5 shown, the utility model discloses a kind of optical fiber amplifier structures, seed source 1, first double optical fiber collimator 2, isolator 3, second double optical fiber collimator 4, gain optical fiber 5, light combiner 6, pump source 7, passive optical fiber 8 and optical fiber output head 9.It is by first input optical fiber 201, second input optical fiber 202, first collimating lens 204, second collimating lens 205 and first glass sleeve 203 that first double optical fiber collimator 2 is formed, first collimating lens 204 and second collimating lens 205 are located in first glass sleeve 203, first input optical fiber 201 is correspondingly arranged with first collimating lens 204, and second input optical fiber 202 is correspondingly arranged with second collimating lens 205.Isolator 3 is by first polarization beam splitter 301, Faraday rotator 302, half-wave plate 303 and second polarization beam splitter 304 sequentially arranged and formed.Second double optical fiber collimator 4 is used to receive collimated signal light, and second double optical fiber collimator 4 is by third input optical fiber 401, fourth input optical fiber 402, third collimating lens 404, fourth collimating lens 405 and second glass sleeve 403 formed, third collimating lens 404 and fourth collimating lens 405 are located in second glass sleeve 403, third input optical fiber is correspondingly arranged with third collimating lens 404, and fourth input optical fiber 402 is correspondingly arranged with fourth collimating lens 405.

[0030] The seed source 1 is used to output seed signal light, the seed source 1 and the pump source 7 are semiconductor lasers or fiber lasers or solid-state lasers. The first double-fiber collimator 22 is used to collimate the seed signal light and the amplified signal light. The isolator 33 is used to pass the collimated signal light and the amplified signal light in one direction, while isolating the back-transmitted light. The second double-fiber collimator 44 is used to receive the coupled collimated seed signal light and the coupled amplified signal light. The pump source 7 is used to output pump light. The seed source 1 and the pump source 7 are continuous or pulsed in operation. The light combiner 6 is used to couple the pump light into the gain fiber 5 and couple the amplified signal light into the passive fiber 8. The gain fiber 5 is used to absorb the pump light, create population inversion, and amplify the signal light. The gain ions in the gain fiber 5 include any one or more of neodymium ions, erbium ions, germanium ions, praseodymium ions, holmium ions, europium ions, ytterbium ions, dysprosium ions, and thulium ions. The passive fiber 8 is used to transmit the amplified signal light output by the light combiner 6 into the first double-fiber collimator 22. The fiber output head 9 is used to output the amplified signal light.

[0031] The seed source 1 emits seed signal light, which is incident on the first input fiber 201 in the first double-fiber collimator 2, collimated by the first collimating lens 204, and then incident on the isolator 3. The signal light passes through the isolator 3 in one direction, and then is coupled by the third collimating lens 404 into the third input fiber 401 in the second double-fiber collimator 4, and then is transmitted to the gain fiber 5. The gain fiber 5, the light combiner 6, and the pump source 7 constitute a backward pumping (reverse pumping). The pump source 7 emits pump light, which is incident on the light combiner 6. The light combiner 6 couples the pump light into the gain fiber 5. After the gain fiber 5 absorbs the pump light, population inversion is formed, and the seed signal light is amplified. The amplified signal light is coupled by the light combiner 6 into the passive fiber 8, and then is transmitted to the second input fiber 202 in the first double-fiber collimator 2. After being collimated by the second collimating lens 205, the amplified signal light is incident on the isolator 3. The incident point of the amplified signal light and the incident point of the seed signal light are horizontally parallel (as shown in Figure 5 FIG. 3). After passing through the isolator 3 in one direction, the amplified signal light is coupled by the fourth collimating lens 405 into the fourth input fiber 402 in the second double-fiber collimator 4, and then is transmitted to the fiber output head 9 to output the amplified signal light.

[0032] In addition, the light combiner 6 and the pump source 7 can also be arranged between the second double-fiber collimator 4 and the gain fiber 5 to constitute a forward pumping, or the light combiner 6 and the pump source 7 are arranged between the second double-fiber collimator 4 and the gain fiber 5, and between the gain fiber 5 and the passive fiber 8 to constitute a bidirectional pumping.

[0033] The specific embodiment of the utility model is described above, but the person skilled in the art should understand that this is only an example, and the person skilled in the art can make various changes or modifications to this embodiment without departing from the principles and essence of the utility model, but these changes and modifications all fall within the protection scope of the utility model.

Claims

1. A fiber amplifier structure, characterized by: The seed source, the first double-fiber collimator, the isolator, the second double-fiber collimator, the gain fiber, the optical combiner, the pump source, the passive fiber and the fiber output head are sequentially connected. The first double-fiber collimator comprises a first input fiber, a second input fiber, a first collimating lens, a second collimating lens and a first glass sleeve, the first collimating lens and the second collimating lens are located in the first glass sleeve, the first input fiber is arranged corresponding to the first collimating lens, and the second input fiber is arranged corresponding to the second collimating lens. The isolator comprises a first polarization beam splitter, a Faraday rotator, a half-wave plate and a second polarization beam splitter arranged in sequence. The second double-fiber collimator is used for receiving collimated signal light, and comprises a third input fiber, a fourth input fiber, a third collimating lens, a fourth collimating lens and a second glass sleeve, the third collimating lens and the fourth collimating lens are located in the second glass sleeve, the third input fiber is arranged corresponding to the third collimating lens, and the fourth input fiber is arranged corresponding to the fourth collimating lens. The seed source is used for outputting seed signal light. The first double-fiber collimator is used for collimating seed signal light and collimating amplified signal light. The isolator is used for unidirectionally passing collimated signal light and amplified signal light, and isolating backward transmission light. The second double-fiber collimator is used for receiving coupled collimated seed signal light and receiving coupled amplified signal light. The pump source is used for outputting pump light. The optical combiner is used for coupling pump light into the gain fiber and coupling amplified signal light into the passive fiber. The gain fiber is used for absorbing pump light, generating population inversion and amplifying signal light. The passive fiber is used for transmitting amplified signal light output by the optical combiner into the first double-fiber collimator. The fiber output head is used for outputting amplified signal light.

2. A fiber amplifier structure as claimed in claim 1, characterized in that: The optical combiner and the pump source constitute forward pumping between the second double-fiber collimator and the gain fiber, or constitute reverse pumping between the gain fiber and the passive fiber. Or the optical combiner and the pump source are simultaneously arranged between the second double-fiber collimator and the gain fiber, and between the gain fiber and the passive fiber, to constitute bidirectional pumping.

3. An optical fiber amplifier structure as claimed in claim 1, characterized in that: The seed source and the pump source are semiconductor lasers, fiber lasers or solid-state lasers.

4. An optical fiber amplifier structure as claimed in claim 1, characterized in that: The seed source and the pump source are continuous or pulsed in operation mode.

5. An optical fiber amplifier structure as claimed in claim 1, characterized in that: The gain ions in the gain fiber include any one or more of neodymium ions, erbium ions, germanium ions, praseodymium ions, holmium ions, europium ions, ytterbium ions, dysprosium ions and thulium ions.

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