• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    l6 Abstract A semiconductor optical amplifier (SOA) which is monolithi- cally integrated with a Mach-Zehnder modulator.The invention is characterized in, that one or more inputaccess waveguides (l)(2),or NXN Multi-Mode-Interference MMI, are connected to an optical splitter such as a Y-branch type, a directional coupler, or a lxNthat is arranged to di-in that at (3,4) vide the light into two or more output waveguides,least two of the splitter's output access waveguidesare used to form a Mach-Zehnder interferometer modulatorwhere at least one arm of the interferometer has a phasemodulator electrode (7,8) (10) and in that a single electricalcontact is arranged to apply a common voltage simultane-or selected (l-ö) ously to a selected portion (ll) in each arm, portions (l2-l5) in each arm of the waveguides that are disposed after the splitter (2) but preceding the phase modu-lation electrodes, or alternatively that said single electri-cal contact is arranged to apply said voltage to a selected (l3) connected to (ll) of portion of the input access waveguide (l)said splitter and in one or more selected portionsone or both of said arms after the splitter (2) but precedingthe phase modulation electrodes to provide gain or reduced optical loss. h:docwork130610 ansökningstextdoc2013-06-10 130014SE
    公开号:SE1350700A1
    申请号:SE1350700
    申请日:2013-06-10
    公开日:2014-12-11
    发明作者:Dave Adams；Jan-Olof Wesström
    申请人:Finisar Sweden Ab；
    IPC主号:
    专利说明:

    Optical semiconductor amplifier.
    The present invention relates to an optical semiconductor amplifier.
    It is advantageous to equip opto-electronic circuits with means for adjusting the signal intensity between the circuit and / or at the output of the circuit. A shape to be able to adjust the power Or usable to compensate either for unwanted optical losses in the circuit, to compensate for aging of the optical call or the optical callers mom or outside the circuit, and / or to adjust the output power level of the circuit.
    One method of enabling adjustments in the strength of an optical signal mom or at the output of an optical circuit is to provide a semiconductor optical amplifier (SOA) somewhere along a light path mom or at the output of the optical circuit. This approach can be used in optical circuits which comprise a composition of discrete components, a hybrid unit which combines discrete and monolithically integrated parts, or a completely monolithically integrated optical circuit.
    The present invention relates to the particular lamp amplification of light before the input of light into a Mach-Zehnder type optical modulator or switch (MZ), and more specifically to the case where an SOA Or is monolithically integrated with a Mach-Zehnder modulator. Prior art has placed an SOA either along the terminal waveguide leading to the modulator input, or placed an SOA in each arm of an MZ-type modulator or switch. p: patranor does doctemp pa1-140508 application text - en ovs.201405191111543911.doc2014-05-08130014EN 2 SOAs configured in this way can provide the general benefits for the optical circuit resulting from optical power adjustment, as previously described. In the special configuration in which an SOA is placed in each arm has an MZ modulator, it is possible to adjust the gain for each SCA and thereby adjust the power ratio between the two branches of the MZ interferometer. It has been found that an uneven input power distribution into the arms has the MZ can be beneficial for transmission performance over fiber.
    However, the placement of an SOA before a Mach-Zehnder, or the placement of an SOA in each arm having a Mach-Zehnder, gives rise to certain disadvantages. First, the addition of either an SOA before a Mach Zehnder or of an SOA in each arm has a Mach-Zehnder the size of the optical circuit.
    Second, the placement of an SOA for a NZ can impair the operation of the circuit, since spontaneous emission noise generated within the SOA can reach other parts of the optical circuit, especially in cases where the SOA and the MZ are integrated with a laser.
    The placement of an SOA in each arm of a MachZehnder interferometer allows adjustment of the power ratio in the two arms. However, if the respective bias voltage that must be applied to the two SOAs is different, there are requirements that the circuit divides the bias current differently between the two SOAs or on the use of an additional current source so that each SOA can be biased in an independent manner. , additional costs for assembly and parts, and can also Increase the total size of and power loss in the circuit. p: patranor does doctemp pa1-140508 application text - en ovs.201405191111543911.doc2014-05-08130014EN 3 The invention described has either eliminated or reduced the consequences of all the disadvantages described.
    The present invention thus relates to a semiconductor optical amplifier (SCA), which is monolithically integrated with a Mach-Zehnder modulator, and characterized in that one or more terminal input waveguides are connected to an optical splitter, such as a Y-branch type splitter, a directional coupler or a 1xN or NxN multimode interference MMI, which is arranged to divide the light through two or more output conductors, by using at least two of the splitter terminal output conductors to form a Mach-Zehnder interferometer modulator where at least one arm of the interferometer has a phase modulation electrode, and single electrical connection means are arranged to connect a common voltage simultaneously to a respective selected part of the habit arm, or respective selected parts of each arm have the conductors arranged after the splitter but before the phase modulation electrodes, or alternatively that said single electrical connection means is arranged to connect said voltage to a selected one part of the terminal input conductor connected to said splitter and to one or more selected parts of one or both of said arms after the splitter but before the phase modulation electrodes, to cause amplification or reduced optical losses.
    The invention is described in more detail below, in part in connection with various exemplary embodiments shown in the accompanying drawings, in which: Figure 1 is a drawing illustrating the principle of the present invention. Figures 2-9 show various embodiments of the present invention. Figure 10 is a diagram. p: patranor does doctemp pa1-140508 application text - en ovs.201405191111543911.doc2014-05-08130014EN 4 The invention relates to monolithically integrated optoelectronic circuits, and more specifically to an SOA which is monolithically integrated with a Mach-Zehnder modulator. Figure 1 illustrates the basic elements of an optical splitter that can be used at the input terminal having a MachZehnder interferometer.
    In Figure 1, the reference numeral 1 denotes a terminal input reference numeral 2 denotes a splitter, 3 and 4 denote terminal output guide conductors, 5 and 6 denote the respective arms having a Mach-Zehnder interferometer, 7 and 8 denote phase modulation sections, 9 denote a combinator optic section and 16 denote a combiner .
    According to the invention, one or more input conductors 1 are connected to an optical splitter 2, such as a splitter of the Ygren type, a directional coupler or a 1xN or NxN multimode interference MMI, which is arranged to divide the light by two or more output conductors 3, 4. of the splitter output wires 3, 4 are used to form a Mach-Zehnder interferometer modulator with two arms 5, 6, where at least one of the two arms has a phase modulation electrode 7, 8. An optical semiconductor amplifier (SCA) is monolithically integrated with Mach-Zehnder modulate.
    A single electrical connection means 10 is arranged to connect a common voltage to a selected part or selected parts 11, 12 of one or more of the conductors which are arranged after the splitter but before the phase modulation electrode or phase modulation electrodes 7, 8, or alternatively to said single electrical connection means is arranged to connect said voltage to a selected part 13 of the terminal input conductor 1 which is connected to said splitter and to a p: patranor does doctemp pa1-140508 application text - sv ovs.201405191111543911.doc2014-05-08130014SE or several selected parts 11 of a or both of said arms after the splitter 2 but before the phase modulation electrodes in order to entail amplification or reduced optical losses.
    According to one embodiment, said selected part or parts comprises the splitter 2.
    According to another embodiment, said selected part or parts comprises the input or terminal output guide or the guides 3, 4 have the splitter.
    According to a further embodiment, said selected part or parts comprise one or two of said two arms having the MachZehnder modulator.
    Said embodiments can be combined. This is illustrated in Figures 2-9. In all figures, the same reference numerals are used to denote the same or corresponding elements.
    In figure 2, the selected parts 11, 12 are covered in the terminal output guide conductors 3, 4.
    The selected parts comprise a layer of electrically conductive material.
    In Figure 3, the selected parts 11, 12 also comprise a part of the splitter.
    In Figure 4, the selected parts also include a part 13 of the terminal input guide but not the splitter.
    In Figure 5, the selected parts include the terminal input guide as well as the terminal output guides and the splitter. p: patranor does doctemp pa1-140508 application text - en ovs.201405191111543911.doc2014-05-08130014EN 6 As shown in Figures 2-5, the selected parts in the respective terminal output guides have different lengths.
    In Figure 6, the selected parts 11, 12 comprise parts 14, 15 of both of said arms.
    In Figure 7, the selected parts 11, 12 comprise both the terminal input guidewires and a part 15 of only one of said arms. In Figure 8, the selected parts 11, 13 comprise both said terminal input guide and a part 15 of one of said terminal output guide.
    In Fig. 9, the selected parts comprise different long parts of said arms.
    It is obvious that many combinations can be made of the named selected parts. Those skilled in the art will have no responsibility to suggest other combinations than those shown in the accompanying figures.
    According to a preferred embodiment, the amplifier SOA is arranged so that the terminal output guide conductors 3, 4 are amplified to different degrees.
    In all the embodiments illustrated in Figures 2-9, the selected parts have different sizes, so that the power fed into the two phase modulation sections having said arms will be substantially different.
    According to the invention, one or more input waveguides are connected to an optical splitter, which may be of the Y-branch type, a directional coupler or a lxN or NxN multimode interference p: patranor does doctemp pa1-140508 application text - sv ovs.201405191111543911.doc201414SE5-0 7 MMI, which divides the light into two or more output guides.
    In a preferred embodiment of the invention, the total length of the reinforcement sections in a first terminal output conductor and in the conductor the Mach-Zehnder arm connected to this first terminal output conductor is substantially different from the total length of the reinforcement sections in a second terminal outlet. The ten-arm arm connected to the exit has the other terminal guide.
    In another embodiment, the length of the gain section of the two terminal guides at the output of the splitter or of the arms which will form the Mach-Zehnder interferometer is substantially the same, but the input power into the phase modulation section of a first arm of the interferometer may be substantially different. into the phase modulation section of the other arm, due to one or a combination of two or more of the following differences between parts of the terminal output guides and / or due to differences between the parts of the interferometer guide conducting the phase modulation sections, namely a difference in optical confinement or the width of the conductor, a difference in width between the metal or semiconductor layers forming the electrical connector, a difference in the bending loss of the terminal output conductor, a difference in passive optical losses due to doping or implantations, a difference in parasitic losses due to the change in metal contacts, or a difference in gain due to a difference in volume or alloy composition has the gain material.
    In all embodiments, an optional phase adjusting section is provided in a modulator arm, which can be used to compute p: patranor does doctemp pa1-140508 application text - sv ovs.201405191111543911.doc2014-05-08130014SE 8 keep the desired total phase difference between absence of high speed modulation, and which can be used, for example, to compensate for differences in phase between the MachZehnder arms nay. The SOA current is varied. The addition of the phase adjusting section can enable rigid independence between the choice of the reinforcement provided by the SOA and the choice of phase difference between the arms compared to the case of maintaining a fixed phase difference and a variable output power with two SOAs being biased independently. A phase-adjusting section Is not absolutely necessary in all cases, as changes in the DC bias voltage of the Mach-Zehnder arms may in some cases be sufficient to mitigate changes in the phase difference between the arms of the interferometer which may occur due to changes in the SOA. in addition, it can be used in that it can compensate for unintentional differences in optical wavelength that arise between the arms during manufacture.
    For example, Figure 10 illustrates a calculation of the power ratio at the entry into the arms of a Mach-Zehnder compared to the total bias current applied to an SOA, where said SOA consists of two amplification sections, a 200pm length amplification section in a first Mach -Zehndervagleader arm and 400 pm in the other arm, and where the respective 200pm and 4001m reinforcement sections Or are connected by a common electrical contact layer. The input power into each arm of the Mach-Zehndern is assumed to be equal to 5.5 mW in the highest curve and 7.4 mW in the lower curve. It can be seen that the power ratio between the} Dada arms varies by about 10% when the bias current to the SOA varies between 100 mA and 150 mA, and that the ratio changes by about 10% when the input power is increased by 30%. Such a vari- p: patranor does doctemp pa1-140508 application text - sv ovs.201405191111543911.doc2014-05-08130014SE 9 ation in the output power ratio is acceptable to allow a transfer performance with less than 1.5 dB long-distance steaming Over 90 km NDSF.
    Optionally, the optical input power to the Mach-Zehndern and / or the bias voltage on the SOA connector may be different to intentionally change the power ratio in the two arms of the Mach-Zehndern, in order to fine-tune the optical signal transmission via fiber so that it is improved, or to w achieve other advantages in the operation of the optical integrated circuit. Thus, the configuration described in these embodiments may provide some degree of descent power sharing.
    In yet another example of the operation of the chip, the optical power input to the input waveguide of the MZ and the bias voltage applied to the common SOA connector over the MZ arms may be changed in such a way that the total sum of the optical power which is fed into the two arms is constant, but where the power ratio between the two Mach-Zehnder arms is different. This method, in order to maintain the installations of the second device and at the same time maintain a constant optical output power, enables an adjustment of the chip output for more favorable transmission performance and / or any other performance variable or lifetime reliability advantage over the optical circuit.
    The invention provides a number of advantages.
    First, the use of a single electrical contact to achieve an uneven amplification of light into the two branches of the interferometer will reduce the cost and size of the circuit compared to circuits requiring two or more SOA bias currents. p: patranor does doctemp pa1-140508 application text - en ovs.201405191111543911.doc2014-05-08130014EN 10 Secondly, the optical circuit can be reduced in relation to previously known embodiments when the splitter (which consists of the terminal input waveguide output) andamal, namely both to share and amplify the light at the same time.
    The third, for the special case of an integration between the SOA and the Mach-Zehndern and a laser call, is an additional advantage of placing the SOA in the manner proposed in this invention, rather than placing the SOA entirely. and the hall before Mach-Zehndern, that any optical reflections from the splitter can be phased to appear after a shorter distance from the laser and with limited two-pass amplification. Reflections with reduced amplitude, and at shorter distances from the laser, may in some cases be less detrimental to the emission properties of a laser that has been designed to operate in the absence of reflections.
    In a fourth example, in comparison with the placement of an SOA between a laser cold and the Mach-Zehnder modulator, all embodiments involving any part of the optical amplification between the terminal output conductors will have the MachZehnder modulator, or in the arms of the Mach-Zehnder modulator, will benefit from a reduced efficiency. the coupling of the spontaneous emission from the SOA to other parts of the circuit, since the spontaneous noise generated in the habit arm Or is uncorrelated in phase with the spontaneous emission in the other arm, and this reduces the size of the said spontaneous emission from the MachZehnder modulator arms into the rest of the circuit. . This reduction in spontaneous emission can favor the lateral mode suppression ratio of a single mode laser call such as Or integrated with the SOA and Mach-Zehnder modulator, for example. In configurations where the SOA described in this invention includes a portion of its length as Or arranged for split- p: patranor does doctemp pa1-140508 application text - sv ovs.201405191111543911.doc2014-05-08130014EN 11 tern, and certain parts of its length in the terminal output guides or guide arms beyond the splitter, as shown in Figures 4, 5, 10, 11, 12, the rear bearing ASE will also be reduced compared to the case of an SOA of the same design for the fully reinforced guide. the ratio before the splitter, assuming a given value for the total reinforcement effect after the SOA.
    In a fifth example, the larger volume of SOA material leads to the circuit being operated at reduced current density for a given malout effect, leading to operation with reduced current density and therefore greater expected long-term reliability of the circuit.
    In a sixth example, possible additional optical surplus splitting losses are avoided by maintaining a guide conductor splitter structure that is geometrically symmetrical, and non-idealities are avoided in reflections from the splitter, or in the splitting ratio itself, which may arise due to manufacturing manufacturing difficulties. construct a splitter that any-ander an asymmetry in the waveguide geometry to Achieve unequal power sharing.
    In a seventh example, in embodiments where the SOA regions are arranged in the two terminal output guides and / or in both output arms, where the usual arm receives about half of the incoming optical power, the SOA will have approximately twice the optical power ratio of the an SOA that is placed in front of the splitter when the SOA electrode is grounded or inverted to attenuate the optical power.
    Some examples have the prior art providing a subset of the advantages described above, but no known embodiment can provide all of these advantages simultaneously. p: patranor does doctemp pa1-140508 application text - sv ovs.201405191111543911.doc2014-05-08130014EN 12 The present invention can be varied as stated above, with respect to said selected parts as well as with respect to the shape and properties of said electrical contact means, without departing from the inventive side.
    Thus, the present invention should not be limited to the embodiments described above, but may be varied within the scope of the claims. p: patranor does doctemp pa1-140508 ansokningstext - sv ovs.201405191111543911.doc2014-05-08130014SE 13
    权利要求:
    Claims (9)
    [1] 1. l3 Claims l. A semiconductor optical amplifier (SOA) which is mono-lithically integrated with a Mach-Zehnder modulator, c h a r a c t e r i z e d i n, that one or more input access(2), or a lxN or NXN waveguides (l) are connected to an optical splitter such as a Y-branch type, a directional coupler,Multi-Mode-Interference MMI, that is arranged to divide thein that at least (3,4) light into two or more output waveguides, two of the splitter's output access waveguides are used to form a Mach-Zehnder interferometer modulator where atleast one arm of the interferometer has a phase modulator electrode (7,8) and in that a single electrical contact (10) is arranged to apply a common voltage simultaneously to a selected portion (ll) in each arm, or selected portions (12- 15) in each arm of the waveguides (l-6) that are disposed after the splitter (2) but preceding the phase modulation electrodes, or alternatively that said single electricalcontact is arranged to apply said voltage to a selected por-(13) tion (l) connected to said (ll) of the input access waveguidesplitter and in one or more selected portions of one orboth of said arms after the splitter (2) but preceding the phase modulation electrodes to provide gain or reduced opti- cal loss.
    [2] 2. A semiconductor optical amplifier (SOA) according toclaim l, c h a r a c t e r i z e d i n, the amplifier SOA is arranged such that the output access waveguides (3,4) are unequally amplified.
    [3] 3. A semiconductor optical amplifier according to claim l or2, c h a r a c t e r i z e d i n,(16)of the Mach-Zehnder modulator, that an optional phase adjust section is provided in at least one modulator arm which adjust section (16) can h:docwork130610 ansökningstextdoc2013-06-10 130014SE l4 be used to maintain a desired total phase difference between the two arms (5,6) in the absence of high speed modulation.
    [4] 4. A semiconductor optical amplifier according to claim l, 2 or 3, c h a r a c t e r i z e d i n, that said selected portion or selected portions comprises/comprise the splitter (2).
    [5] 5. A semiconductor optical amplifier according to claim l, 2, 3 or 4, c h a r a c t e r i z e d i n, that said selected portion or selected portions comprises/comprise the input (l) or output(3,4) access waveguide(s) of the splitter (2).
    [6] 6. A semiconductor optical amplifier according to claim l, 2, 3, 4 or 5, c h a r a c t e r i z e d i n, that said selected portion or selected portions comprises/comprise one or two ofsaid two arms (5,6) of the Mach-Zehnder modulator in a por-tion of said arm/arms that precedes the phase modulation(7,8) electrodes and in that the selected portions have a different size such that the power launched in the two phase modulation sections (7,8) of said arms (5,6) will be substan-tially unequal.
    [7] 7. A semiconductor optical amplifier according to claim l, 2, 3, 4, 5 or 6, c h a r a c t e r i z e d i n, that thecombined length of the amplifying sections in a first outputaccess waveguide and in the waveguide of the MZ arm that isconnected to that first output access waveguide, is substan-tially unequal to the combined length of the amplifying sec-tions in a second output access waveguide and in thewaveguide of the Mach-Zehnder arm that is connected to the output of the second access waveguide. h:docwork130610 ansökningstextdoc2013-06-10 130014SE
    [8] 8. A semiconductor optical amplifier according to claim l, 2, 3, 4, 5 or 6, c h a r a c t e r i z e d i n, that thelength of the amplifying section in the two access waveguidesat the output of the splitter, or in said arms is substan-tially equal, in that said selected portion or selected por-tions are different from each other such that the power en-tering the phase modulation section in a first of said armsof the interferometer is substantially unequal to the powerentering the phase modulation section in the second of saidarms, due to one or a combination two or more of the follow-ing differences between portions of the output accesswaveguides and/or due differences between the portions ofwaveguides of the interferometer that precede the phase modu-lation sections, namely a difference in optical confinementor waveguide width, a difference in the width of the metal orsemiconductor layers that form the electrical contact, a a difference a dif- difference in output access waveguide bend loss,in passive optical losses due to doping or implants,ference in parasitic losses due to the proximity of metalcontacts, or a difference in gain due to difference of volume or alloy composition of the gain material.
    [9] 9. A semiconductor optical amplifier according to claim l, 2, 3, 4, 5, 6, 7 or 8, c h a r a c t e r i z e d i n, that a laser is integrated with the SOA and Mach-Zehnder modulator. h:docwork130610 ansökningstextdoc2013-06-10 130014SE
    类似技术:
    公开号 | 公开日 | 专利标题
    US9244327B2|2016-01-26|Mach-Zehnder modulator with backplane voltage equalization
    CN110168824B|2020-11-27|Semiconductor optical amplifier, method for manufacturing the same, and optical phase modulator
    JP3530404B2|2004-05-24|Wavelength selectable laser source
    SE1350700A1|2014-12-11|Optical semiconductor amplifier
    US9664981B2|2017-05-30|Integrated light source and light output control method
    WO2017135381A1|2017-08-10|Optical transmitter and light intensity monitoring method
    US9762029B2|2017-09-12|Semiconductor laser and optical integrated light source including the same
    US8260096B2|2012-09-04|Photonic integrated circuit having bent active components
    JP6543188B2|2019-07-10|Wavelength multiplex optical transmitter and control method thereof
    JP2013118315A|2013-06-13|Semiconductor laser device and semiconductor laser module
    JP2015065406A|2015-04-09|Wavelength variable light source and wavelength variable light source module
    Tanaka et al.2014|Flip-chip-bonded, 8-wavelength AlGaInAs DFB laser array operable up to 70° C for silicon WDM interconnects
    SE520951C2|2003-09-16|Multi-wavelength selective switch for switching and redirecting optical wavelengths
    US7286731B2|2007-10-23|Monolithically integrated optical coupler with substantially no splitting loss
    JP2002076481A|2002-03-15|Optical direct amplifier and control method therefor
    US20190041581A1|2019-02-07|Tunable light source and optical module
    US11070027B2|2021-07-20|Variable wavelength light source and method for controlling wavelength switching of variable wavelength light source
    JP2016111214A|2016-06-20|Wavelength variable light source, control method for wavelength variable light source, and manufacturing method of wavelength variable light source
    JP2019057541A|2019-04-11|Semiconductor optical integrated element
    US10295738B2|2019-05-21|Electro-optical modulator
    US20030179441A1|2003-09-25|Polarisation insensitive optical amplifiers
    JP2016174095A|2016-09-29|Optical transmitter and optical transmitting apparatus
    US20220019021A1|2022-01-20|Photonic integrated circuit for amplifying optical signals
    JP6671571B1|2020-03-25|Optical node device
    WO2021084627A1|2021-05-06|Optical coupling method
    同族专利:
    公开号 | 公开日
    SE537250C2|2015-03-17|
    US9209606B2|2015-12-08|
    US20140362433A1|2014-12-11|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US5539571A|1992-09-21|1996-07-23|Sdl, Inc.|Differentially pumped optical amplifer and mopa device|
    JPH0961766A|1995-08-19|1997-03-07|Nec Corp|Semiconductor optical modulator|
    FR2787593B1|1998-12-17|2001-02-02|Cit Alcatel|MACH-ZEHNDER MODULATOR WITH A VERY HIGH EXTINCTION RATE|
    US7295783B2|2001-10-09|2007-11-13|Infinera Corporation|Digital optical network architecture|
    US7633988B2|2003-07-31|2009-12-15|Jds Uniphase Corporation|Tunable laser source with monolithically integrated interferometric optical modulator|
    EP1840607B1|2005-01-20|2013-11-06|Fujitsu Ltd.|Optical waveguide device and semiconductor device|
    JP2013080011A|2011-09-30|2013-05-02|Sumitomo Osaka Cement Co Ltd|Optical frequency comb signal generator|JP2013168500A|2012-02-15|2013-08-29|Mitsubishi Electric Corp|Optical semiconductor device|
    US11081863B2|2017-04-19|2021-08-03|Finisar Sweden Ab|Optical device and method for controlling such a device|
    DE102019122429B3|2019-08-21|2020-09-24|Zacharias Ceranski|Apparatus and method for processing optical signals|
    法律状态:
    2021-10-05| NUG| Patent has lapsed|
    优先权:
    申请号 | 申请日 | 专利标题
    SE1350700A|SE537250C2|2013-06-10|2013-06-10|Optical semiconductor amplifier|SE1350700A| SE537250C2|2013-06-10|2013-06-10|Optical semiconductor amplifier|
    US14/025,083| US9209606B2|2013-06-10|2013-09-12|Semiconductor optical amplifier|
    [返回顶部]