TW459449B - Optical amplifier with power dependent feedback - Google Patents

Abstract

An optical amplifier includes an optical feedback resonant laser cavity (OFRC) including a power dependent loss element (PDLE) having the characteristic that as the incident laser power on the PDLE increases the cavity loss decreases. The OFRC with the PDLE provides optical gain control or optical power control for a WDM amplifier or a single channel power equalization amplifier (PEA), respectively. A 1xNxN WADM node incorporating more than one of these amplifiers, at least some of which commonly share a pump source, and a method for controlling a transient power change in a single channel optical amplifier or reducing a DC gain error in a WDM optical amplifier that are subject to dynamically variable operating conditions at an input of the amplifier, are also disclsoed.

Description

4 59 d 4 9 Λ7 s_______ 耵 V. Description of the invention (() Field of the invention: The present invention relates to fiber optic WDM transmission systems and the use of optical amplifiers therein, and in particular to optical feedback resonant laser cavity (〇 ^ Rc) It contains a power-dependent loss element (PDLE) as optical gain control (OCC) or optical power rate control (qpc), and a method for implementing the control, which is particularly useful for amplifying wavelengths (DM) transmission mode ^ Background of the invention: '... wavelength d min h is a proven technology to increase the capacity of existing optical networks. Generally WDM systems use multiple optical signal channels, and each channel is set to a special wavelength. · «Together, generate signal channels, multiplex them to form optical signals composed of individual optical signal channels, transmit them through single-waveguides, and demultiplex to make each channel up to 1 Receive ϋ. Multiple optical channels can be used in optical amplifiers, for example, to increase the size of Xiao (face) M, and Qian Zhitong can transmit over long distances. Use a sporadic multiplexer in the communication network to fetch one or more channels from the multiplexed data stream, let the remaining channels pass through to the down-link, and add a new transmission channel to at most one sickle stream. "Add another-to guide the re-construction of the routing link of the optical network, that is, because the conditions change in the general conditions, the miscellaneous protection section sets up the road to reverse the specific information flow. π As shown in Figure 1, traditional financial links include input and amplification gains of control gains 121, 123, a pair of lx version of the multiplexer / demultiplexer 125,…, and one; I train addition / occurrence Switcher i2g. The-general form of discussion! (210 X 29 7 Public Therapy) A 5 9 4 A __ V. Description of the invention (Tie) = 7, Seven are lxNxi links here, ϊ! For the existence of a single input amplifier and a single-output amplifier, two ride the same Equalize and control the gain amplifier. Ordering wavelength addition / occasion multiplexing enables the m number to be routed or transmitted by different hops, and to pass through different road technologies. _Every—add people, and occasionally change the number of dB for each channel after switching. The method of equalizing the per-link transmission power will monitor the per-channel power and use a variable optical attenuator (VOA) 131 in each channel path to maintain a fixed channel power. Because the phase is slow and the GA response is slow, the security of the channel plus people from milliseconds to seconds depends on the VOAS method used. Although the vOA response time does not pose a problem at present (because switching channels can be expected to interrupt some communication volume), there is! M operation compensation in the output amplification, which is imposed by the need to touch the residual channel. For example, VOA with feedback control must adjust the channel power, which can be changed by Y dB between channels (that is, multiplied by a factor of 10 (// [[0])), as previously explained. In order to protect the signal in the worst case, its tN— 丨 channels are simultaneously added with all Y dB excess power. The pumping power of the output amplifier before V0A can generate a response needs to support 1)) + 1 channel power. In other words, if N is quite large, the compensation of the pumping power of the protection residual channel is about Y dB. One suggested way to solve this problem is to replace the output amplifier and VOA of 1xNχ1 structure with multiple parallel power equalization amplifiers (pea) as shown in Figure 2 to form the so-called 1xNχN architecture, because there is a fixed control optical output. Each PEA can be designed to exist in its saturation range so that the output signal power is determined by the pumping power and is essentially independent of the input power. The simulation results show that the difference between the output power of these PEA and the input power of 6dB is only kl 459449 _________ B7 I V. Description of the invention (')

I

I · »ν— ^ ^, -1 · 0. 5dB, and it has been shown that the phase difference is idlh. Although the price is more competitive in this way, the VOA and complex round-out amplifiers can be removed by the system, and the separation pump for each PEA. The operating diodes are replaced by a common pumping light source, and each parallel amplifier has a known temporary power control requirement (on channel join / out). Without this control, the amplifier's reversal will be higher when the channel is occasional, and there will be a large temporary power spike when another channel is added to the amplifier. Repeated amplification of the temporary spike along the series amplifier will cause component damage Or larger pump power compensation to protect the remaining channels. However, since these parallel amplifiers share the pumping light source, it is not easy to achieve individual temporary control by conventional electronic control, such as by adjusting the power of millet. .---n: tl it-One way to solve this problem is to place an optical feedback chirped laser cavity (OFRC) in each PEA so that temporary control is applied individually to these parallel amplifiers, or even to them. Common use of pumping power. To control temporary changes in PM power, OFRC is manufactured so that when the signal channel is removed by PEA, an optical power control (OPC) laser is activated (excited). Ideally, the 0pc laser is turned off (stops excitation) when the signal channel appears in the PEA, so that pEA only saturates the signal channel and draws all the energy available from the pumping power of the signal channel. However, due to the γ dB power variation between the signal channels, the 0pc laser must turn off the signal channel with the lowest possible channel power. To achieve this, OFRC cavity losses must be quite high. However, high loss when the laser is turned on: power consumption produces low 0PC laser power, and thus the amplifier has high inversion. Therefore, if i Fan such as a high power signal channel is added to a higher inversion PEA, which uses low power | laser to saturate, there will be a temporary power | head peak due to the high inversion. In order to eliminate temporary sharpness, OFRC requires a lower cavity loss to pass through the materials: Orange Standard (CNS) Λ4 Specification (2 丨 UX297) 459449 Λ7 B7

And higher OPC laser power. In the OFRC there is the opposite of high loss and low loss. In addition to the temporary power control of the PEA described previously, the WDM input amplifiers shown in Figures 1 and 2 are used to control the gain to reduce the steady state (DC) gain error. The general technique for implementing this control in the optical amplifier of Object 1 includes manufacturing Each / amplifier has an OFRC, such as an optical gain control (0GC) laser cavity. It is understood that this configuration will make the optical gain at the excitation wavelength equal to the passive loss. Therefore, for a homogeneous medium, once the gain is fixed at a specific wavelength at all wavelengths in a certain spectrum, the optical gain is also locked. Once the 0GC laser wavelength and the passive loss at this wavelength are determined, the amplifier gain spectrum is also determined. Those skilled in the art understand that doped bait fiber (EDF) is not a pure homogeneous medium for light amplification; however, it is a certain degree of non-uniformity. This situation will cause frequent perforation. When the 0GC laser power is increased due to coupling out the channel or increasing the pumping power, the spectral hole becomes deeper in the signal band at the excitation wavelength and a steady state (DC) gain error occurs. This is shown schematically in Figure 3 (). Therefore, when έέ is added or made or the power is changed, the problem of gain error due to spectral holes generated by 0GC lasers needs to be solved. Summary of the invention: An embodiment relates to an optical amplifier, which includes a gain medium; a pump 4 light source that implements its optical fiber to excite the medium; a photophase laser cavity (0FRC) is exposed to the gain medium; and In the middle power-dependent loss element (PDLE), Wang Wang showed that there is no impairment to increase the fT of the incident laser power. First read the back and remember the apple term before writing this page)-[Γ-I 1 · I, () A4l: -Lt &-(2l0x) Λ7 B7 V. Description of the invention (f) function. In the present invention, when the amplifier input conditions are dynamically changed, OtRC with PDLE provides optical gain control (0GC) for WDM or optical power control (0PC) for single channel amplification. In the preferred embodiment, the p0L packet is a passive component such as a saturated absorber. The saturable absorber can be an optical fiber doped with rare earth elements, preferably an erbium-doped optical fiber. In another aspect of the present invention, the PDLE can be an effective component such as a light intensity module, that is, an acousto-optic I harmonic resonator becomes an electro-optic § Zhou harmonic benefit, which has feedback control. The priority 0 is that C is in the form of a circular cavity, or a linear cavity. The 0FRC structure and related components used to couple the 0FRC to the amplifier essentially determine the laser excitation wavelength. For example, the two-cavity cavity will be preferentially dissipated to the amplifier by two wavelength selective couplers, which will be combined to transmit the signal frequency band wavelength and turn the wavelength band of 0GC laser or 0pc laser to the feedback space Cavity. Similarly, the linear cavity preferentially uses a grating structure as a mirror / emitter at the end of the cavity, and its reflection is related to the excitation wavelength light and emits light related to the signal band wavelength. The amplifier is preferentially EDFA, but can also be a semiconductor amplifier, Raman amplifier, 3]: 111011111 amplifier, or other types of amplifiers, which operate within the traditional or extended optical band width. In another embodiment, the wavelength addition / depletion multiplexing (drawing) amplification optical transmission link includes a MinxNoin end-demultiplexer, where is} and Nout>, and the demultiplexing wavelength range is △, the optical signal It is a group of fixed optical signals, each with a wavelength of λ, or a group of N optical signals, each of which has a wavelength range of △ heart (from 丨 to Ν-1); X bars added / Coupled signal transmission paths are all connected to one end of the port, where each-signal ί | side i has a light material A | § of the employment agency f, and please read the attention of tvg before filling in the decayed wood page). Τ '' 459449

Industry '4 adds at least some Nin optical signal multiplexing affinity to the other end of the 1 propagation path, and is characterized in that each of a group of N f optical amplifiers contains an optical feedback stray laser cavity (OFRC ) 5: To the relative magnification $ if 益 介 ^ and further-including power-dependent loss (PI) LE), which presents a function that gradually decreases 彳 u to Mg and increases the laser light intensity. As explained in the example of the optical amplifier just now, preferably 0GC or 0pc = the second cavity is in the form of a% -shaped cavity, or a linear cavity, and the excitation wavelength is essentially a combination of wavelength mosquitoes. For example, the annular cavity is preferentially closed to the amplifier by two wavelength selective light couplers, which transmit the signal band wavelength and the light-wavelength laser wavelength. At the same time, the line, Shicai I first relies on the grating structure as a cavity end reflector / emission II so that the reflected light is equivalent to the excitation wavelength and the emitted light _ is equivalent to the domain county wavelength. In a preferred embodiment, PDLE is a passive component such as a saturated absorber. The saturable absorber is a -segment passive hetero rare-earth element optical fiber, and more preferably a hybrid optical fiber. On the other hand, PDLE is also an active component, such as a light intensity 3 week hunting benefit, that is, a sound and light modulator with feedback control. Another embodiment of the present invention is a method for controlling a temporary power change in a single-channel optical amplifier or reducing a% gain error in a WDM optical amplifier. The helium amplifier performs a dynamic change at the input of the amplification. The final part, and including the OFRC coupling to the gain medium with an output power amplifier: It is dynamically determined by the operating conditions, and it includes the step of reducing the 0FRC cavity loss when the output power of the 0Fl? C wheel increases, and vice versa, so The amplifier gain is dynamically changed to reduce the gain or power variation of the amplifier.

Shichuan Little WW Family (C’VS) Λ4 Specifications 8 7

459449 t invention provides a device and method to improve optical control or power control. The advantages of the hybrid system (compared with the electronic system) are well known and well-known (ie, the gift wave, signal input power, and spring power are not related). The present invention is particularly useful for the application of machine chirps and soliton propagation systems, in which accurate channel power is important, and chirping of the power 1 at the junction of a plane produces advantages. Due to the scaling of the channel power after pEA at every link ^ The power gambler recognizes that the gain continuous wave cannot be accumulated along the continuity amplifier. Other features and advantages of the present invention will be revealed in the following detailed description, and some of them can be understood from the description or from the description of the implementation, the scope of the patent application and the description of the drawings. It is understood that the previous general description and the following detailed description are merely examples of the invention and are provided to provide a concept or framework for understanding the principles and features of the invention. The drawings are intended to provide a further understanding of the invention and to form part of the specification. The drawings show embodiments of the invention and accompanying descriptions for explaining the principles and operation of the invention. Brief description of the drawings: The first diagram (Fig. 1) is a schematic diagram showing a conventional IxNxl WADM connection, which has a single input and output amplifier; the second diagram (Fig. 2) is a schematic diagram showing a traditional IxNχN WADM connection, It has a power equalization amplifier (PEA) and a shared pump; the third figure A (Figure 3a) shows the gain and wavelength west line of the two different signal channels without PD LE in the present invention: .'ίνί 人? IUUiii 用 准 （ CNS > Λ4 grid (2ilK < 297 cm) {〇A 7 137 4 5 9 4 4 The third figure B (Figure 3b) is the gain and wavelength curve of the present invention with two different numbers of PDLE signal channels; the fourth Figure (Figure 4) is a schematic diagram of an OFRC amplifier according to the present invention, which includes a PDLE embodiment of the invention; Figure 5 (Figure 5) is a graph of OGC laser incident laser power and power-related loss of a PDLE according to an embodiment of the invention; The sixth figure (Figure 6) is an oil line diagram of the optical signal wavelength and gain data of the two MOGC amplifiers, when the OGC cavity loss is a fixed value (only VOA) and when the OGC cavity contains the PDLE of the embodiment of the present invention; Figure 7 (Figure 7) is an enlarged view of the embodiment of the present invention In the < xc cavity, there are fixed losses and PDLE—a group of eight signal channels. When seven channels are coupled to one channel, the gain error and wavelength curve are amplified by a 0 GC amplifier. Figure 8 (Figure 8) Two graphs of temporary gain error versus time comparison, with and without the PDLE OGC amplifier of the present invention, the residual channel is coupled out and added; and the ninth figure (Figure 9) is a single-channel amplifier (PEA) The three curves of output power and a tb are compared. It has no control, fixed her optical feedback control, and has PDLE optical feedback control in OFRC, and uses the 1557 · 2nm channel of _6_ power to join PEA. Description of the figures and symbols of the attached components: Optical amplification 1G; 彳 #_ 面 简 丨 2; amplification into the M amplifier output 16; pumping light source 18; coupler 2Qn _) 32; Gongshenguanyou (CNS) Λ4λί {^ (2 «〇Τ297 ^ 7 丨 广 ._ A7 ____ Λ33ΛΛ 9 B7 V. Description of the invention (.qi) — ~~ — Loss of pieces (PDLE) 34; solution Multiplexer 101; signal propagation path 103; end 105; pumping path 12 丨; multiplexer 07; path end 丨 09; link 110; traditional WADM link 120; wheel amplifier 121; output amplifier 123; multiplex β 125; demultiplexer 127; switch 129; variable optical attenuator (VOA ) 131. Detailed description of the preferred embodiments: The preferred embodiments of the present invention will now be described in detail, and examples thereof are shown in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. An exemplary embodiment of an optical amplifier of the present invention is shown in Fig. 4 and is generally indicated by reference numerals. Before explaining the present invention, people understand the present invention and many aspects, and explain the physical properties of the following two types of optical control, namely optical power control (0pc) and optical gain control (OGC). Optical power control: The power equalization amplifier (PEA) used here is a single optical signal channel amplifier operating in a saturated state I, as opposed to a WDM amplifier (the optical gain control is described below). When the signal channel is coupled out, there is no longer any saturated signal in the PM, and it is hidden due to magnetic inversion. If the signal I channel is added from input to amplification n under high reversal conditions, it has a temporary peak of energy. When the news # comes out, the optical power control! (GPG) Economics_Acuity Cavity_0 will start to make a snow shot ^! QPG laser god improves the reflection of the lyonic device can control the optical feedback space by I Cavity loss is achieved. If the gain of the amplifier is higher than that of the OPC laser wavelength in the case of the single i-plane, the gain of the OPC laser wavelength is higher than the optical feedback space.

Λ 7 Β7 cavity loss, when the signal is out, the PC laser will start (excitation) and cause the amplifier gain to decrease. 0PC laser saturates the amplifier and adjusts the inversion of the amplifier. Ideally, when the signal channel is added to the amplifier, the 0PC laser will be turned off; otherwise, the 0PC laser draws the energy provided by the pump light source, and eliminates the concept of equalizing PEA surplus and equalizing power by using only the signal = except this Since the signal power can be changed by a factor such as γ dB, when the signal channel with the lowest possible channel power is added, the PC laser shutdown is very important. ^ This can be fixed by generating in the optical feedback cavity. (High) attrition. At the 0PC laser wavelength, the loss must be higher than the gain of the amplifier saturated with the lowest possible signal power so that the 0PC laser stops energizing when a signal appears. However, high cavity loss refers to the low 0PC laser power and high amplifier inversion when the signal is coupled out. If the joining channel is of higher power, a temporary power spike due to high amplifier inversion will occur. To reduce transient power spikes, the fixed loss in the optical feedback cavity must be reduced. If the cavity loss is fixed, the opposite is true with higher or lower optical feedback cavity losses. The opposite situation is solved by adding the PDLE of the present invention to an optical feedback laser cavity. When the signal appears, the 0PC laser power decreases due to energy conservation. Therefore, losses will increase in the PDLE cavity. Increasing power-related losses in the optical feedback cavity will further reduce the OPC laser power. The feedback effect between pDLE and opc laser power thus turns off the 0PC laser. With pDLE, 0PC lasers can be turned off with weak signal power. On the other hand, when the isfU tiger is consumed, the amplifier inversion (amplifier gain) and the instantaneous amplification of the amplifier will increase. When the center wavelength of the wavelength-selective element is close to ASE, it returns to the cavity and reaches PDLE, and the PDLE loss will be reduced. Therefore the cavity (CNS) Λ-IAV ril · (2! Ox) < 3 459449 12 A7 B7

Reduced loss will result in greater feedback in the cavity and increase in ASE intensity into the cavity. In the end, the power-dependent loss becomes lower enough to turn off the zero laser, and the PDLE changes from an OPC laser to a lower loss. With the PDLE of the present invention, once the OPC laser is started and the gain medium has lower inversion, the cavity has lower loss. In addition, when the OPC laser is activated, the amplifier inversion is equivalent to the inversion which is saturated by the highest possible signal. Therefore, temporary power spikes caused by the addition of high power signals are reduced. Optical gain control: Usually EDFA operates in the saturation range. Therefore, the gain spectrum of a multi-channel (WDM) EDFA changes with the amplifier input conditions, such as the change in pump power input power. In other cases, gain drift will be promoted, which will have a negative effect. The concept of controlling optical gain via an optical feedback resonant cavity (OFRC) is to dynamically change the OGC laser power when the turn-in conditions change to compensate for the resulting gain offset. However, because the chirped gain medium is non-uniform, the OGC laser creates a spectral hole in the gain spectrum at the OGC excitation wavelength. Therefore, when the OGC laser power is increased by decoupling channels or increasing the pumping power, the spectral hole becomes deeper at the excitation wavelength. If the laser cavity loss is fixed, the inversion of the pumped gain medium must be increased to keep the optical gain value at the bottom of the spectral hole equal to the optical loss. Therefore, the gain of the amplified channel is increased to generate a DC gain error. This is shown in Figure 3 (a) (without PDLE in the cavity). By comparison, as shown in FIG. 3 (b), when the PDLE of the present invention is added to a laser cavity, the cavity power consumption decreases as the intensity of the incident OGC laser light increases, and the power-dependent loss is reduced. And to compensate for the effect of the increase in inversion caused by the spectral holes generated by the OGC laser. Therefore the DC gain error will be

Order

CNS) (2ΙΟχ 297λ > ^) I 459449449 Λ7 ____________ B7 Description of Invention (\ >) Referring to FIG. 4, the fiber amplifier 10 includes a section of doped erbium-doped fiber (E)) F) 12 liters of a gain-increasing medium Consume to amplifier input 14 and output ΐβ. The optical feedback resonance cavity (〇FRC) 30 is preferentially a ring-shaped cavity form, which is connected to the amplification gain on the upstream and downstream sides of EDF 12 by wavelength selective supplementary benefits 24, 26, respectively. The coupling wavelengths of the 26 handles and the close ones determine the laser wavelength of OFRC 30. The optical isolator 28 preferentially determines the direction of the laser signal (OGC laser or 0pc laser) as shown in the figure, which runs in a clockwise direction in the same direction as the input signal. The pumping light source 18 that excites the EDf gain medium is preferentially coupled to the EDF 12 input via a coupler 20 for a WDM coupler. The pumped light source 18 is preferably a 980 nm or 1480 nm laser diode. The structure shown in Figure 4 provides a common propagation signal and a pump (Figure 4 from left to right); however, it is understood that the pumping light source 18 can be arranged near the output of the EDF 12 so that it propagates in the opposite direction relative to the SFL signal. It can be changed and the amplifier can be pumped using side excitation or cladding pumps that are well known in the industry. In the exemplary embodiment shown in FIG. 4, a variable optical attenuator (VO A) 32 is located within the OFRC 30 along a power-dependent loss element (PDLE) 34, which is also located downstream of the OFRC of the VOA 32. According to the present invention, PDLE 34 is characterized in that its loss value (and cavity loss) decreases as the intensity of incident light emitted by the OGC laser or OPC laser increases. This is shown in Figure 5 where the power-dependent loss characteristics of pdle 34 are shown schematically. As shown, PDLE loss decreases non-linearly as PDLE light intensity increases. In the preferred embodiment, POLE is a passive component such as a saturated absorber. Those skilled in the art understand that the electron dynamic EDF between the 3/2 state and the ground state is very suitable for this application. Top priority, saturation

(CNS) (2i〇297 /, v ^) 4594 49 14 Λ7 B7

The absorber is a piece of EDF 12, which has a short half-life of the 113/2 state of Er ions, which is less than about 1¾ seconds. Other saturated absorbers such as dye or semiconducting rhenium saturated suction blowers are also suitable. In another embodiment, p [) LE. 34 is an active device for tuning the intensity of laser light, such as an acousto-optic tuner, which uses a feedback lever to dynamically adjust the cavity based on the load conditions that are magnified to The annular OFRC 30 combined with PDLE 34 according to the present invention effectively provides optical gain control (0GC) or optical power control (OPC) to the WDM amplifier or PEA, respectively. It is understood that another configuration can include a linear unitary geometry (not shown) with appropriate end reflectors such as reflections, thumbs, chirps, wavers, or other suitable elements. Although Li Yun Light Source 18 and EDF 12 combine to provide a signal amplification medium with a 15 0 0 mn communication frequency window (1520nm-1565nm C-band and 1565-1625nm L-band) signal amplification medium, the present invention is not limited to this case, and is well-known for this technology It is understood that the present invention can be applied to any suitable spectral gain medium. Some examples include semiconductor optical amplifiers that have waveguides that are currently pumped or doped with different dopants. The waveguides consist of glass, glass ceramics, mixed forms, or other components or forms with appropriate laser sources. The following description of FIG. 4 is an exemplary OGC embodiment of the present invention. The figure shows that the EDFA 10 with OFRC 30 includes a power-dependent loss element 34 ° PDLE 34 is a 1-meter EDF 12, and its power-dependent loss characteristics are shown in FIG. 5

As shown. VOA 32 is set to 8.3dB at 1527nm excitation wavelength. Snow and cavity 30 generate fixed loss, and the gain frequency of the amplifier is set. At eight wavelengths (channels), each channel power is -1 OdBm. Signal measurement optical benefits. For comparison, the characteristic is that VOA 32 is set to 9,5dBA0FRC (^ first; «read the review and fill in the wooden page) ϊ '/ Λί-^-

Claims (1)

Α8 BS CS DS Saturated Absorber is doped Jin 459449 h. ≪]? Π:] 1_-a link of wavelength add / couple multiplex (WADM) amplification optical transmission, which includes: MmxN0Uti ^ multiplexer, Wherein Min g; [and 1; N such as in and / or out signal propagation paths, each of which has an end coupled to an Nnut port; light and -amplification benefits, which have a gain-increasing medium located in N Add and / or uncover at least one path of the optical signal propagation path; and NinxZ0Uti ^ port multiplexing, where z〇ut g 1, where the other end of each of the n paths is coupled to an end port; which is characterized by: Each optical optical amplifier includes an optical feedback resonant laser cavity exposed to a gain medium; and a power-semi-dependent loss element is located in each of the optical feedback resonant laser cavities, which exhibits a decreasing loss as an increasing incident laser. As a function of the intensity of the emitted light, this light enters the power-dependent loss element. 2. The connection according to item 1 of the patent application scope, wherein the power-related loss element is at least one active component and passive component. 3. According to the connection in the second patent claim, the active component includes the light intensity module and feedback control. 4 ' The connection according to item 2 of the scope of the patent application, wherein the passive component comprises a saturable absorber. ° 5 · The connection according to item 4 of the scope of patent application, in which the rare-earth element is an optical fiber. 6. According to the connection in the fourth scope of the patent application, the saturated absorber is a section C < \ TS) {2ΐί) χ 297 公 符) 459449 Α δ m cs m Apply for patent Fan Yuan Push the oblique optical fiber. i nh Cunli manages the link of item 2, where the optical feedback laser is a ring-shaped cavity. 8. According to the connection of item 2 of Hiyaligan, where the optical feedback certificate vibrating laser air moon is a linear cavity ^ 9. According to the connection of item 7 of the scope of patent application, the optical laser cavity by Wavelength selection_ 合! 1_ 合 至 AGE quality_Total visceral length enters the optical feedback cavity. 10 'According to the connection in item 9 of the scope of the patent application, the excitation wavelength propagates in the direction of the optical feedback hybrid and "to the silk." 11. The connection is made according to the ageing material, and the shooting medium is doped by mistake. Optical fiber. 12. The connection according to the patent application, which is difficult, where the optical fiber is a europium-doped fiber. Τ '13. According to the connection in the patent application, the connection includes the pump light source to the group. A number of optical amplifiers in the propagation path / in order to increase the excitation energy to the amplifier. 3 依. According to the link of the patent claim _ 丨 3, its μ is a good news, and its towel pump branch source is 16. The link in the scope of the patent application, which further enters a well optical amplifier and closes to the demultiplexer at the input of the link. Among them, the optical ^ radiation space and a power-related loss 5-, 5-, A8 BS C'8 m 459449 \ t; · Lifanyuan 17. According to the link in the patent request of the patent, the optical amplifier is a single channel amplifier. 18: According to the link in the patent application scope, the optical amplifier 19_ An optical amplifier An optical feedback resonant laser cavity coupled to the gain medium; and a power-dependent loss element located in the optical feedback resonant laser cavity, It shows that reducing the loss is a function of the increasing incident laser light intensity input to the power-related loss element. 丨: 11 20_According to the 4th patent of laJS, the amplifier of item 9 where the amplifier is a professional amplifier and its main characteristics The operating condition of the amplifier is dynamically changed at the input end of the amplifier, which generates a gain error at the output of the amplifier, so the optical feedback is that the laser cavity shows a dynamically changing loss or gain is a dynamically changing operation The function of the condition is to improve the gain error. 21. The amplifier according to item 19 of the patent application scope, wherein the amplifier is a single-channel amplifier, which is mainly characterized in that the amplifier applies dynamic changing operating conditions at the end of the amplifier wheel. The output power of the wheel is changed, and the optical feedback hybrid laser cavity shows a dynamic change. Or "oil change to hide the secret Lin still function as the output variation. 22. A patent application based on the range of _ amplifier, wherein the power dependent loss element comprises at least one member and the passive member initiative. AR B8 C8 m 459449 Among them, the active component is composed of light, and the passive component is composed of the line intensity modulator and feedback control of the amplifier according to item 22 of the scope of patent application. 24. The amplifier is composed of a saturated absorber according to item 22 of the scope of patent application. Lie • The amplifier according to item 24 of the scope of patent application, wherein the saturated absorber is an optical fiber of #hetero rare earth element. 26. The amplifier according to item 9 of the patent application, wherein the saturated absorber is a section of erbium-doped optical fiber. °° 27_ The amplifier according to item 19 of the application, wherein the optical laser cavity is a ring cavity. 28. The amplifier according to item 19 of the application, wherein the optical cavity laser cavity is a linear cavity. 2 ^ ’According to the item of the patent scope, the optical cavity laser cavity is switched from the wavelength selection element to the gain medium to fit the excitation wavelength into the optical feedback resonant laser cavity. 30. The amplifier according to item 27 of the Shenzhai patent scope, wherein the excitation wavelength propagates in the same direction as the input optical signal D 31. The amplifier according to item 9 of the patent scope, wherein the gain medium is an optical fiber doped with rare earth elements. ^ 3 + 2. The amplifier according to item 31 of the application, wherein the rare-earth doped I optical fiber is an erbium-doped optical fiber. 33. The amplifier according to item 19 of the scope of patent application, wherein the pumping energy comes first. I i 34. The amplifier according to item 19 of the scope of patent application, in which the pumping energy is electric AS BB CS D8 5 9 4 4 9 Qingyuan Fanyuanliu Energy. 5 The amplifier according to item 19 of the scope of patent application, in which the gain medium 36. —A method for controlling temporary power changes in a single-channel optical amplifier or reducing it in a WDM optical amplifier] ^ Gain error, the amplifier imposes dynamically changing operating conditions at the input, And a gain medium including an OFRC coupled to a power amplifier with a wheel-out power, the power dynamically determines 1 operating condition, the method includes the steps of reducing the OFRC cavity loss when the output power is increased, or vice versa, Therefore, the gain medium of the amplifier is changed tragically to reduce the gain or power change in the amplifier. 37 ^ The method according to item # 5 of the May patent application, wherein when the incident incident output increases or decreases, the cavity cavity loss will be reduced or increased, respectively, and = at 0 = the appropriate value is provided, which is almost in the valve. As the output power of RC incident 4 and absorption n increases, the absorber loss decreases. (CN, 'S) AiXU * {210X29 / ^)