EP1440495A2 - An optical light source - Google Patents
An optical light sourceInfo
- Publication number
- EP1440495A2 EP1440495A2 EP02772580A EP02772580A EP1440495A2 EP 1440495 A2 EP1440495 A2 EP 1440495A2 EP 02772580 A EP02772580 A EP 02772580A EP 02772580 A EP02772580 A EP 02772580A EP 1440495 A2 EP1440495 A2 EP 1440495A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- optical
- light source
- source according
- fibre
- optical light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/036—Optical fibres with cladding with or without a coating core or cladding comprising multiple layers
- G02B6/03616—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference
- G02B6/03638—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference having 3 layers only
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02295—Microstructured optical fibre
- G02B6/02314—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes
- G02B6/02342—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes characterised by cladding features, i.e. light confining region
- G02B6/02361—Longitudinal structures forming multiple layers around the core, e.g. arranged in multiple rings with each ring having longitudinal elements at substantially the same radial distance from the core, having rotational symmetry about the fibre axis
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02295—Microstructured optical fibre
- G02B6/02314—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes
- G02B6/02342—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes characterised by cladding features, i.e. light confining region
- G02B6/0238—Longitudinal structures having higher refractive index than background material, e.g. high index solid rods
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/255—Splicing of light guides, e.g. by fusion or bonding
- G02B6/2552—Splicing of light guides, e.g. by fusion or bonding reshaping or reforming of light guides for coupling using thermal heating, e.g. tapering, forming of a lens on light guide ends
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/26—Optical coupling means
- G02B6/262—Optical details of coupling light into, or out of, or between fibre ends, e.g. special fibre end shapes or associated optical elements
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02295—Microstructured optical fibre
- G02B6/02314—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes
- G02B6/02319—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes characterised by core or core-cladding interface features
- G02B6/02333—Core having higher refractive index than cladding, e.g. solid core, effective index guiding
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02295—Microstructured optical fibre
- G02B6/02314—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes
- G02B6/02342—Plurality of longitudinal structures extending along optical fibre axis, e.g. holes characterised by cladding features, i.e. light confining region
- G02B6/02376—Longitudinal variation along fibre axis direction, e.g. tapered holes
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/42—Coupling light guides with opto-electronic elements
- G02B6/4201—Packages, e.g. shape, construction, internal or external details
- G02B6/4202—Packages, e.g. shape, construction, internal or external details for coupling an active element with fibres without intermediate optical elements, e.g. fibres with plane ends, fibres with shaped ends, bundles
- G02B6/4203—Optical features
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/005—Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping
Definitions
- This invention relates to an optical light source, an optical amplifier, and a fibre
- optical amplifiers that can output powers of lOOmW to 10W, or higher powers, and can amplify many wavelength
- optical amplifiers use single-mode optical fibre whose core is doped with one or more rare-earth ions such as Erbium. These amplifiers are pumped by single- mode pump diodes and hence they provide limited power output that is insufficient for
- the pump source also need to be wavelength stabilised which is achieved either
- Cladding pumped Ytterbium (Yb) doped fibre lasers operating at around 977nm have been the subject of significant technical and experimental activity in recent years.
- fibre lasers is to reach high enough population inversions, since otherwise emission occurs on the quasi-four level transition around 1040nm, with large reabsorption at the two-level
- Yb-doped fibre lasers are known as being notoriously noisy, with poor relative intensity noise (RIN) characteristics that significantly narrow their
- Erbium-doped fibre amplifiers have revolutionized optical communications over the last ten years.
- the increasing need for capacity drives the amplification requirements, namely operation over the full C-Band with low noise and
- cladding-pumped EDFAs are sensitized (co-doped) with ytterbium in order to improve the
- an optical light source comprising a laser diode, beam shaping optics, and an amplifying
- the amplifying optical fibre comprises a waveguide comprising a
- the waveguide is doped with a rare earth dopant, and wherein
- the laser diode is able to produce optical pump power which is coupled to the waveguide by the beam shaping optics.
- the beam shaping optics may comprise a first lens.
- the first lens can be formed on
- the beam shaping optics may comprise a second lens.
- the second lens can be a
- the cylindrical lens can be a cylindrical microlens which may have a
- lens may have a uniform refractive index profile, or may have a graded refractive index
- the laser diode can be a multimode laser diode.
- the laser diode can comprise at
- the laser diode can comprise at least one a diode bar.
- the laser diode can comprise at least one diode stack.
- the laser diode can emit 0.1 W to 50 W of optical pump power.
- the laser diode can emit 0.1 W to 50 W of optical pump power.
- the cladding can have an outer diameter in the range lOum to lOOum.
- cladding can have an outer diameter in the range 15um to 50um.
- the core and/or cladding can be doped with at least one of germanium,
- the core can be configured to be a single mode waveguide.
- the optical pump power can facilitate optical radiation from the rare earth dopant
- the optical radiation from the rare earth dopant in the waveguide can be coupled to an amplifying optical device, wherein the amplifying optical device is one of an optical amplifier, a laser or a distributed feedback laser, and wherem the amplifying optical device
- the optical radiation from the rare earth dopant in the waveguide can be coupled to
- optical devices are configured to be pumped by the optical radiation.
- the cladding may be circular.
- the cladding may be substantially rectangular.
- cladding may have a non-circular shape.
- the core may be centrally located in the cladding.
- the core may be offset from the centre of the cladding.
- the optical radiation from the rare earth dopant in the waveguide can be coupled to an optical amplifier and wherein the optical radiation can be used as a pump source for the
- the optical radiation from the rare earth dopant in the waveguide can be coupled to
- optical radiation can be used as a pump source for the optical amplifiers.
- the amplifying optical fibre can comprise a microstructured mesh surrounding the cladding.
- the microstructured mesh may be sealed at either end of the amplifying optical
- the amplifying optical fibre for example by heating the amplifying optical fibre with an electric arc, a flame or a
- a glass ferrule may be placed onto either end of the amplifying optical fibre prior to applying heat.
- the glass may be silica.
- the optical light source can comprise feedback means for providing feedback in the
- the feedback means can be a reflector.
- the reflector can be formed from a cleave in the amplifying optical fibre.
- the reflector can be a fibre Bragg grating.
- the reflector can be a dichroic filter.
- the dichroic filter may be
- the amplifying optical fibre can be configured as a source of amplified spontaneous
- the rare earth dopant can be contained in the core.
- the rare earth dopant can be any rare earth dopant.
- the rare earth dopant can be contained in both the core and the
- the rare earth dopant can be configured in a region surrounding the centre of the
- the region surrounding the centre of the waveguide can be a ring surrounding the core.
- the ring can have a thickness in the range 1 to lOum.
- the rare earth dopant can comprise Yb and it is preferable that the laser diode emits at a wavelength that is absorbed by the Yb.
- the optical light source may comprise a dichroic filter that reflects in the wavelength range 975nm to 980nm, and wherein the
- optical light source comprises a second port, the optical light source being an optical
- the waveguide is configured to emit optical radiation in a wavelength range from 975nm to 980nm, wherein the optical
- radiation is coupled to at least one erbium-doped optical amplifier via an optical coupler
- the optical radiation is used as a pump source for the optical amplifier. It is preferred that the Yb is configured in a region surrounding the centre of the waveguide.
- the amplifying optical fibre may comprise an absorber to attenuate unwanted
- the absorber may be a saturable absorber or an unsaturable absorber. It is preferred that the rare earth dopant is Yb and the absorber is samarium configured to
- the absorber may be in the core, the cladding, or in both the core and the cladding. It is
- the Yb and the absorber is configured in a region surrounding the centre of
- the amplifying optical fibre comprises a microstructured
- the cladding may have an outer diameter in the range 25 ⁇ m to 35 ⁇ m.
- the rare earth dopant can comprise Erbium and it is preferable that the laser diode
- the rare earth dopant can comprise Erbium codoped with Ytterbium, and it is
- the laser diode emits at a wavelength that will be absorbed by the
- the rare earth dopant can comprise Neodymium and it is preferable that the laser diode emits at a wavelength that is absorbed by the Neodymium.
- the rare earth dopant can comprise Thulium and it is preferable that the laser diode
- the rare earth dopant can comprise Praseodymium and the laser diode emits at a
- the rare earth dopant can be selected from the group comprising Ytterbium, Erbium, Neodymium, Praseodymium, Thulium, Samarium, Holmium and Dysprosium, or is Erbium codoped with Ytterbium, or is doped with a transition metal or semiconductor.
- the invention also provides an optical amplifier comprising the optical light source.
- the optical amplifier may be configured to have low polarisation dependent gain.
- the invention also provides an optical fibre laser comprising the optical light
- the invention also provides a method for pumping a plurality of optical amplifiers
- each optical amplifier comprises a pump
- the method comprising the steps of providing an optical light source according to the
- the invention also provides a method for pumping a plurality of fibre lasers each
- the invention can also be considered to be a source of amplified spontaneous
- Figure 1 is a diagram of a light source according to the present invention.
- Figure 2 shows the light source coupled to an optical amplifier
- Figure 3 shows the light source coupled to a plurality of optical amplifiers
- Figure 4 shows waveguide comprising feedback means
- Figure 5 shows a ring-doped amplifying fibre
- Figure 6 shows an optical fibre being stretched by the application of heat
- Figure 7 shows a lens formed on the end of an optical fibre
- Figure 8 shows a second fibre with a curved fibres being spliced to an amplifying
- Figure 9 shows a cylindrical lens on the end of an amplifying fibre
- Figure 10 shows a beam shaping optics comprising a second lens
- Figure 11 shows a microstructured mesh sealed at either end of an amplifying fibre
- Figure 12 shows a glass ferrule placed onto an amplifying fibre
- Figure 13 shows an amplifying optical fibre with a non-circular cladding
- Figure 14 shows an amplifying optical fibre with an offset core
- Figure 15 shows the absorption and emission spectra for ytterbium ions in silica
- Figure 16 shows the dependence of threshold power 161 on cladding diameter for a silica optical fibre having a ytterbium-doped single mode core
- Figure 17 shows a two-emitter pump module
- Figure 18 shows the output spectra of the pump module
- Figure 19 shows the output power as a function of laser diode current for the pump module
- Figure 20 shows a cross-section of a ytterbium-doped jacketed air-clad (JAC) fibre
- Figure 21 shows a fibre laser comprising the JAC fibre
- Figure 22 shows the output power versus launched power for a fibre laser
- amplified spontaneous emissions (ASE) source that comprise the JAC fibre
- Figure 23 shows the temporal behavior of the fibre laser comprising the JAC fibre
- Figure 24 shows an amplified spontaneous emission (ASE) source comprising the JAC fibre
- Figure 25 shows the output spectrum of the ASE source
- Figure 26 shows the temporal behavior of the ASE source
- Figure 27 shows an erbium doped fibre amplifier (EDFA) that is pumped with the EDFA
- Figure 28 shows EDFA's spectral gain characteristic for two different input power
- Figure 29 shows the EDFA's spectral noise figure characteristic
- Figure 30 shows the cross-section of ring-doped ytterbium JAC fibre
- Figure 31 shows an ASE source comprising the ring-doped JAC fibre
- Figure 32 shows a fibre laser comprising the ring-doped JAC fibre
- Figure 33 shows the output power as a function of absorbed power for the ASE
- Figure 34 shows the spectral dependence of output power for the ASE source
- Figure 35 shows a measurement of relative intensity noise with frequency for the
- Figure 36 shows an optical amplifier comprising a gain clamping laser diode
- Figures 37 to 40 show the spectral output response of the optical amplifier when the
- Figure 41 shows the dependence of gain and noise figure measured as a function of
- Figure 42 shows the spectral dependence of gain for different levels of gain
- Figure 43 shows the spectral dependence of polarization dependent gain when the
- optical amplifier is pumped with the ASE source and a laser-diode
- Figure 44 shows the power variation at the output of the EDFA when the input
- Figure 45 shows the doping profiles of the fibre shown in Figure 20;
- Figure 46 shows the doping profiles of the fibre shown in Figure 30;
- Figure 47 shows an amplifying optical device comprising a first port and a second
- Figure 48 shows an amplifying optical device comprising a thin film filter
- Figure 49 shows an arrangement in which pump power is amplified by the
- Figure 50 shows a preform assembly comprising solid rods and capillaries
- Figure 51 shows an optical fibre drawn from the preform assumebly of Figure 50
- Figure 52 shows a preform assembly comprising a non-circular preform
- Figure 53 shows an optical fibre drawn from the preform assembly of Figure 52.
- Figure 1 shows an optical light source comprising a laser diode 1, a beam shaping
- the amplifying fibre 3 comprises a waveguide 4 comprising a core 5 and a cladding 6, wherein the waveguide 4 is doped with a rare earth
- the amplifying fibre 3 is preferably made from silica or silicate glass.
- amplifying fibre 3 can be made from phosphate glass or other soft glasses.
- the laser diode 1 can be a multimode laser diode.
- the laser diode 1 can be a
- the laser diode 1 can be a diode bar.
- the laser diode 1 can be a
- the laser diode 1 can comprise a combination or a plurality of laser diodes,
- the laser diode 1 can emit 0.1W to 50 W of optical pump power.
- the laser diode 1 can emit 0.1W to 50 W of optical pump power.
- the beam shaping optics 2 can comprise a first lens 71.
- the first lens 71 can be
- Tension is applied to the amplifying fibre 3 and heat is applied. This results in a neck 61 being formed in the amplifying fibre 3.
- the amplifying fibre 3 then separates into two.
- a second fibre 81 having a curved surface 82 can be
- the amplifying optical fibre 3 will generally have a circular fundamental mode and
- the first lens 71 may be a cylindrical lens 91 formed by
- a cylindrical lens 91 is shown in Figure 9 and is further described in US patent 6332053 which is hereby
- the beam shaping optics 2 can comprise a second lens 100 as shown in Figure 10.
- the second lens 100 can be a cylindrical lens.
- the cylindrical lens can be a cylindrical
- microlens which may have a shape, such as circular, elliptical or hyperbolic, designed to
- the cylindrical lens may have a uniform refractive index profile, or may
- the cladding 6 can have an outer diameter in the range lOum to lOOum.
- the cladding 6 can have an outer diameter in the range 15um to 50um.
- the cladding 6 can be circular.
- the cladding 6 can be non-circular.
- the core 5 and/or cladding 6 can be doped with germanium, phosphorous, boron, aluminium and/or fluoride.
- the core 5 can be configured to be a single mode waveguide. Alternatively the
- the core 5 can be configured to be a multimode waveguide.
- the core 5 can be circular, ring-
- the core 5 can be configured centrally with respect to the cladding 6.
- a non-circular cladding 6 can increase the overlap of light propagating in the cladding 6 with the core 5.
- the optical pump power 8 can stimulate optical radiation 9 from the rare earth
- the optical radiation 9 may be amplified spontaneous
- the optical radiation 9 may be dominated by stimulated emission.
- Figure 2 shows the optical radiation 9 from the rare earth dopant 7 in the waveguide
- optical radiation 9 is used as a pump
- the coupling is achieved using a lens 21. It is
- the coupling is achieved using an optical fibre coupler.
- Figure 3 shows the waveguide 3 coupled to apluralify of amplifying optical devices 33 via an optical fibre 31, apluralify of optical couplers 32.
- the optical radiation 9 is used
- the amplifying optical devices 33 are arranged as a pump source for the amplifying optical devices 33.
- the amplifying optical devices 33 are arranged to provide a pump source for the amplifying optical devices 33.
- optical amplifiers can be optical amplifiers, lasers, distributed feedback fibre lasers or distributed Bragg reflector fibre lasers.
- the amplifying fibre 3 can comprise a microstructured mesh 111 surrounding the
- microstructured mesh 111 may be sealed at either
- the first lens 71 may be formed on the end 112 in
- the end 113 may be cleaved as shown in
- FIG. 11 or fusion spliced to an output fibre (not shown).
- the cleaved end provides a flat surface for subsequent coating of the end face of the fibre, for example with a dichroic
- a glass ferrule 120 may be placed onto the amplifying fibre
- a reflecting material 123 may be placed onto the glass ferrule.
- the reflecting material 123 may be a metal such as chrome, silver or gold, and the metal may be deposited using electroless plating techniques. This configuration has advantages
- FIG. 4 shows feedback means 40 for providing feedback in the waveguide 4, the
- the feedback means 40 can be a reflector.
- the reflector can be
- the reflector can be a fibre Bragg grating.
- the reflector can be a mirror.
- the reflector can be a dichroic mirror.
- the amplifying fibre 3 can be configured as a source of amplified spontaneous
- the rare earth dopant 7 can be contained in the core 5.
- the rare earth dopant 7 can be contained in the cladding 6.
- the rare earth dopant 7 can be
- Figure 5 shows the rare earth dopant 7 configured in a region 50 surrounding the
- the ring 51 can have a thickness 52 in the
- the rare earth dopant 7 can comprise Ytterbium (Yb) and it is preferable that the Yb.
- laser diode 1 emits at a wavelength that is absorbed by the Yb. It is preferable that the
- waveguide 4 is configured to emit optical radiation in the wavelength range 970nm to
- the Yb can be configured in a region surrounding the centre of the waveguide 4. Alternatively, the Yb
- the optical radiation can be coupled to at least one erbium-doped optical amplifier via an optical coupler, and wherein
- the optical radiation is used as a pump source for the optical amplifier.
- the amplifying fibre 3 may comprise an absorber to attenuate unwanted optical radiation.
- the absorber may be a saturable absorber or an unsaturable absorber. It is
- the rare earth dopant is Yb and the absorber is samarium configured to
- the absorber may be in the core, the cladding, or in both the core and the cladding. It is
- the Yb is configured in a region surrounding the centre of the waveguide.
- the amplifying fibre comprises a microstructured mesh surrounding the amplifying fibre
- the cladding and that the cladding has an outer diameter in the range of 15 ⁇ m to 75 ⁇ m.
- cladding may have an outer diameter in the range 25 ⁇ m to 35 ⁇ m.
- Figure 13 shows an amplifying fibre 130 comprising a core 5, a non-circular
- the air cladding region 136 includes an air cladding region 111, and an outer jacket 133.
- the 111 comprises holes 135, 139 that extend longitudinally along the amplifying fibre 130.
- the holes 135 are formed from the inside of capillaries used to fabricate the amplifying
- the holes 139 are formed from the interstitial spaces between the capillaries
- the amplifying fibre 130 is used to fabricate the amplifying fibre 130.
- the amplifying fibre 130 is used to fabricate the amplifying fibre 130.
- 130 may comprise only holes 135 (if the interstitial holes 139 are closed up by the
- capillaries are used instead of capillaries, or if the capillaries are collapsed by the application of
- non-circular cladding 136 it better matches the near field
- the non-circular cladding 136 can be rectangular, square, triangular, D-shaped, or a circular shape comprising flats that are
- non-circular cladding 136 can be machined prior to preform assembly.
- the dimensions of the non-circular cladding 136 can be
- Figure 14 shows an amplifying fibre 140 in which the core 5 and region 131 is
- the amplifying fibre 140 is an example of a
- the amplifying fibre 140 comprises an air cladding region 142 and an outer jacket 143 that can advantageously be configured to ensure that the core 5 is
- fibre is advantageous for fusion splicing, whilst having a core that is not central with
- the core 5 may comprise the rare-earth dopant 7. Alternatively, or additionally, the rare-earth dopant 7.
- amplifying fibre 130 may comprise a region 131 that surrounds the core 5 and this region
- Figure 13 also shows an outer region 132 that
- the outer region 132 may be doped with a saturable or an
- the region 131 may be doped with Ytterbium ions and the outer
- region 132 may be doped with samarium, and the amplifying fibre 130 used as a source of
- Such a source can be susceptible to radiation induced or fed back at 1035nm to 1060nm, and the samarium is useful to absorb this radiation.
- the rare earth dopant 7 can comprise Erbium (Er) and it is preferable that the laser diode 1 emits at a wavelength that is absorbed by the Er.
- Er Erbium
- the rare earth dopant 7 can comprise Er codoped with Yb, and it is then preferable
- the laser diode 1 emits at a wavelength that will be absorbed by the Yb.
- the rare earth dopant 7 can comprise Neodymium (Nd) and it is preferable that the laser diode 1 emits at a wavelength that is absorbed by the Nd.
- Nd Neodymium
- the rare earth dopant 7 can comprise Thulium (Tm) and it is preferable that the laser diode 1 emits at a wavelength that is absorbed by the Tm.
- Tm Thulium
- the rare earth dopant 7 can comprise Praseodymium (Pr) and the laser diode 1 emits at a wavelength that is absorbed by the Pr.
- the rare earth dopant 7 can be selected from the group comprising Ytterbium,
- Erbium codoped with Ytterbium or is doped with a transition metal or semiconductor.
- Cladding-pumping with high-power multimode diode pump sources is the preferred
- the inner cladding diameter should be
- Yb-ions have a strong emission cross-section at 976 nm.
- high power radiation can be achieved in the wavelength region that is preferred for pumping EDFAs.
- Figure 15 shows the absorption spectrum 151 and emission spectrum 152 of Yb- ions in silica glass.
- the emission 152 and absorption 151 cross sections at around 976 nm are equal so in order to achieve lasing one has to reach a 50% population inversion.
- Transparency pump intensity i.e. the pump intensity required for a 50% population
- inversion is approximately 2.5- 10 4 W/cm 2 or 10 W for a double clad fibre with 200 ⁇ m
- Figure 16 shows the dependence of threshold power 161 as a function of pump cladding diameter 162 for a Yb-doped single-mode core in silica glass. Assuming an acceptable threshold for such a pump source is around 500 mW, then Figure 16 shows that
- the pump cladding diameter 162 should be below 30 ⁇ m.
- the pump threshold P th should be small compared with the available pump power P p and second the slope
- a homogeneously broadened gain medium such as Yb-doped silica fibres
- G kN 0 A d ⁇ d ( ⁇ ) ⁇ [ ⁇ e ( ⁇ ) + ⁇ a ( ⁇ )]n 2 - ⁇ a ( ⁇ ) ⁇ L , (1)
- ⁇ a are the emission and absorption cross sections, respectively and n 2 is the fraction of
- ⁇ d is the value of the normalized modal intensity
- nm can be expressed as
- the 1030 nm gain is proportional to the cladding-to-core area ratio A dd i ng /A c o re
- nm 7 dB (lasing from one cleaved end) then the pump absorption will be in the region of
- the pump cladding diameter should not exceed 25 ⁇ m since in
- the doped core should be single-
- Figure 17 shows a pump module 171.
- a pump source 171 was used based on a two-emitter assembly, that is the pump source 171 used two laser diode chips whose outputs were combined togetiier and launched into the Yb-doped fibre. Similar pump module can be procured Milon Laser Co. from St.
- the New Optics Limited product has a product name "Ultra-6". Each laser diode is capable of
- Figure 19 shows the output power 191 measured as a
- the doped fibre should have high efficiency (greater than
- the pump cladding area should be below 600 ⁇ m 2 (i.e. core-to-cladding diameter ratio should be
- NA numerical aperture
- Figure 20 shows a jacketed air clad (JAC) fibre 200 that meets these criteria.
- Yb-doped fibre 200 has a raised index core 201 co-doped with boron and germanium, a
- the doped core diameter was 8
- the germanium doping makes the core 201 photosensitive which is
- the resulting JAC fibre 200 was 1 to 2 ⁇ m.
- the JAC fibre 200 has a polymer coating 206 (not
- the JAC fibre 200 comprises a
- region 451 doped with germania (in order to make the core 201 photosensitive) and a region 452 doped with Ytterbium.
- the region 452 included the core 201 as well as a ring
- the JAC fibre 200 during the collapsing stages of the (earlier) preform manufacturing process, leading to the well-known refractive index dip at the centre of the fibre 200.
- This refractive index dip is not shown in Figure 45.
- the 915 run pump absorption was 1 dB/m.
- the pump cladding NA ie the effective numerical aperture
- wavelength selective reflector such as a fibre Bragg grating or a filter. Another way is to
- the fibre as a source of amplified spontaneous emission ASE - ie an ASE source.
- fibre lasers ultimately deliver more power and are
- wavelength selective elements and is less noisy.
- Figure 21 shows a fibre laser 210 comprising the pump source 171 and the JAC fibre 200.
- a laser cavity 211 was formed by a first fibre Bragg grating 212 and a second
- the first fibre Bragg grating 212 was written directly into the core 201 and the second fibre Bragg grating 213 was written into a photosensitive single mode
- optical fibre 216 procured from FiberCore Limited which had a second-mode cut-off at
- second grating 213 was 20% and the reflectivity of the first grating 212 was 15% to 20%.
- the length 215 of the cavity 211 was 4m.
- Figure 22 shows the output power 221 of the fibre laser 210 versus the launched power 222 defined as the power that is coupled into the inner cladding 202 from the pump
- Figure 23 shows the temporal dependence of the output power 221 of the fibre laser
- the characteristic time 233 is set
- the characteristic time 233 is equal to 40
- Figure 24 shows a high power ASE source 240 comprising the pump source 171, the JAC fibre 200.
- the configuration of the ASE source 240 is almost identical to that of
- the fibre laser 210 except there are no gratings and the output end 241 of the source 240 is angle-cleaved.
- the output power 224 of the ASE source 240 is shown plotted against launched
- Figure 25 shows the normalised intensity 251 of the ASE source 240 as a function
- fibre Bragg gratings as is commonly used in sources for pumping EDFAs and
- Figure 26 shows the normalised output power 251 as measured over time 252.
- the ASE source 240 maximum output power available from the ASE source 240 was 400 mW.
- source 240 provides relatively high power, has a stable output wavelength with temperature
- Figure 27 shows an erbium doped amplifier EDFA 270 that was pumped by the ASE source 240.
- the EDFA 270 comprises tap couplers 271, photodiodes 272, isolators
- WDM couplers 274 erbium doped single mode fibre 275, control electronics 276 and a variable optical attenuator 277.
- Signal light is input at the input port 278 and output at
- Pump power 2711 was delivered by the 978 nm ASE fibre source 240 via a 1 x 4 pump splitter 2710.
- the pump splitter 2710 was constructed from optical fibre
- the gain and noise figure of the EDFA 270 was measured as a function of wavelength 281 at signal input power levels of -1 IdBm and -3 IdBm.
- Figure 28 shows the
- the fibre pump source 240 is capable of pumping up to four EDFAs
- Figure 30 shows a preferred embodiment of a ring-doped JAC fibre 300.
- fibre 300 comprises a core 301 that is doped with Germania, a rare-earth doped region 302
- the diameter of the JAC fibre 300 is approximately
- the core is single-moded with a
- Figure 46 shows the dopant profiles 460 of the JAC fibre 300 as a function of radius 465.
- the JAC fibre 300 comprises a region 461 doped with germania (in order to
- fibre 300 during the collapsing stages of the (earlier) preform manufacturing process, leading to the well-known refractive index dip at the centre of the fibre 300.
- the core can be ring-doped with germania or phosphorous and co-doped with Ytterbium.
- the emission cross-section spectrum of Yb ions in silica glass has a relatively narrow (approximately 4 nm wide) peak
- a laser can be formed using
- the wavelength selection arises from the shape of the emission cross-section.
- a laser can be formed using wavelength selective feedback from at least one
- Wavelength selective feedback can be achieved using a filter such as a
- fibre Bragg grating It is also possible to simply pump a Ytterbium doped fibre in order to realise a source of amplified spontaneous emission.
- Figure 31 shows an ASE source 310 comprising a laser diode 311 emitting at
- the JAC fibre 300 was 3.25m long. The length is very dependent upon fibre design and the amount of pump power that is launched into the fibre. Depending on Yb concentration and disposition, a length
- the optical fibre 313 is a photosensitive single mode
- fibre comprising a photosensitive waveguide 3111 comprising a core and a cladding.
- a fibre Bragg grating 3110 (or other reflector) can be written into the fibre 313 in order to reflect pump radiation at 915nm back into the fibre
- the fibre 313 should preferably have a photosensitive cladding and a photosensitive core in order that the fibre Bragg grating 3110 can be configured to reflect the pump light, most of
- the JAC fibre 300 should be antireflection coated and/or cleaved
- optical fibre 313 is shown cleaved at an angle 314
- the optics 312 comprised
- both cylindrical and spherical lenses which may be a graded refractive index (GRIN) lens
- the dichroic filter 319 can be configured at
- Such unwanted signals can damage a laser diode.
- one of the at least one dichroic filters 319 is possible to configure as an end-
- the rejection filter can be positioned between the 975 nm highly reflective in the 1020 - 1100 nm wavelength range (and optionally at around 975 to 980 nm), and configured at an angle such that it does not reflect light back into the fiber 300.
- the rejection filter can be positioned between the 975 nm highly reflective in the 1020 - 1100 nm wavelength range (and optionally at around 975 to 980 nm), and configured at an angle such that it does not reflect light back into the fiber 300.
- the rejection filter can be positioned between the 975 nm highly reflective in the 1020 - 1100 nm wavelength range (and optionally at around 975 to 980 nm), and configured at an angle such that it does not reflect light back into the fiber 300.
- the rejection filter can be positioned between the 975 nm highly reflective in the 1020 - 1100 nm wavelength range (and optionally at around 975 to 980 nm), and configured at an angle such that it does not reflect light back into the fiber 300.
- the rejection filter must not reject 975 nm
- filter 319 that perform the essential tasks, namely reflecting 975 nm light back into the fiber, transmitting 915 nm pump light from the diode 311 to the fiber 300, and preferably
- 975 nm rejection filters can also be used, outside the design path for 975 nm light that
- the end 316 can then be cleaved (as shown) or left with a curved surface, or first lens 71 as
- the dichroic mirror 319 on the fibre end 316.
- Figure 32 shows a fibre laser 320.
- the fibre laser 320 is similar to the ASE source
- the optics 321 comprises a cylindrical and
- the JAC fibre 300 was 0.75m long, but 0.25m to 2m may be more preferable for
- the cylindrical and spherical lenses are coated with coatings that provide broadband antireflection in the wavelength range from around 91 Onm
- the broadband dichroic filter 322 should provide high transmission
- broadband dichroic mirror 322 is preferably deposited on the end of the JAC fibre 300 after the air holes are sealed by application of heat (which can be achieved for example by placing the fibre 300 into an electric arc).
- the dichroic mirror 322 can be
- the laser 320 may optionally comprise a reflector 324 for reflecting
- the reflector 324 may be a fibre Bragg grating, or may be implemented with a narrowband dichroic mirror place
- a multimode pump reflector that is configured to reflect the 915nm light
- the 975 to 980 nm reflectivity should be in the range
- the ASE-source 310 is simple as no external feedback is required to produce emission at
- RIN is essentially white, and the output is essentially unpolarized even in the presence of
- the drawbacks of the ASE-source 310 are a lower efficiency and
- This sensitivity to back reflections can be
- Figure 33 shows the measured output power 331 of the ASE source 310 and the output power 332 of the laser 320 plotted against the absorbed power 333.
- Figure 34 shows the measured output power 331 of the ASE source 310 and the output power 332 of the laser 320 plotted against the absorbed power 333.
- Figure 35 shows the relative intensity noise RIN 351 of the ASE source 310 and the RIN 352 of the laser 320 plotted
- the suppression of emission at around 1040 nm is more than 20
- the spectral width of the fibre laser is 3 to 4 nm and the centre wavelength is situated at 976 nm, which is near the peak of the 980 nm absorption band of erbium-ions in silica glass.
- the spectral width of the fibre laser is 3 to 4 nm and the centre wavelength is situated at 976 nm, which is near the peak of the 980 nm absorption band of erbium-ions in silica glass.
- 320 was 0.5 nm, mainly determined by the characteristics of the reflective grating 323.
- fibre-based pump source is as important as the wall-plug efficiency and output power.
- the ASE-source 310 has no cavity and hence its RIN is white
- the ASE-source 310 is below— 130 dB/Hz and thus should not generate any extra
- the ASE-source 310 is an ideal pump source for
- the fibre laser pump source 320 has several RIN peaks 354, 355, 356.
- the relaxation oscillation peak occurs at 450 kHz at a RIN level of-
- the RIN peak is dependent on the cavity length and hence on the position of
- the grating output coupler In our measurements the cavity length was 3.25m.
- the laser 320 is very low and limited only by the sensitivity of the measurement device ( — 145 dB/Hz). Thus by optimising the device length of the fibre laser 320, it should be a suitable
- the unpolarized output of the ASE source 310 is also advantageous for pumping.
- the RIN noise of DFB fibre lasers can be induced not only by the RIN of the pump but also from fluctuations in its polarization state and
- the laser source 320 was capable of delivering
- Both sources 310, 320 are suitable for
- DBR distributed bragg reflector
- Figure 36 shows an erbium doped amplifier (EDFA) 360 comprising a preamplifier
- the EDFA 360 comprises tap couplers 366, an input photodiode 367, an output photodiode
- Fibre 3614 provides coupling of residual pump power from the pre-amplifier 361 to the booster amplifier 362.
- the EDFA 360 has an input 3616 an output 3617, and a
- Coupler 366 photodiode 367 and an isolator 368.
- the pump power for both the pre-amplifier 361 and the amplifier 362 is provided by the ASE source 310 whose output was split through a 75/25 coupler 364.
- preamplifier 361 is co-pumped with 200mW while the booster amplifier 362 is counter-
- a wavelength division multiplexer coupler 3612 was
- the wavelength division multiplexing (WDM) coupler 3612 was selected to couple 977nm radiation from the ASE source to the coupler 364, and undesireable longer wavelength emission at 1035nm to the termination
- the termination 3613 is designed to minimize reflection at 1035nm back into the
- the WDM coupler 3612 is implemented with index matching gel and/or an angle cleave.
- DFB laser diode 365 at 1570nm (outside the transmission band) with a maximum output power of 40m W is used to clamp the gain and control transients in the booster amplifier
- the power from the DFB laser diode 365 is added and dropped from the amplifier using thin-film WDM couplers 3615. When channels are dropped, the gain compression
- the EDFA 360 was tested with 32 channels each having different central
- the total input power of the EDFA 360 was OdBm, i.e. the
- the EDFA 360 had a saturated output power of +23dBm
- the gain-flattening filter (GFF) 363 was designed such that the EDFA 360 had
- the gain flatness is better than +/- 0.5 dB for the input power range.
- the dual-stage configuration and the high pump power available allow for a noise figure better than
- Figure 42 shows the gain 421, 422, 423, 424 with eight channels for "clamping
- the gain tilt that is the
- FIG. 43 shows the polarisation dependent gain (PDG) 431, 432 versus
- semiconductor laser diode (not shown) respectively as the pump source of the EDFA 360.
- the ASE source 310 provides a O.ldB reduction in the PDG of the EDFA 360. This is
- the output of the optical amplifier should not vary if another
- the output power of the surviving channel at 1550.92nm was measured using a fiber Bragg grating filter to filter the output power from ASE and other unwanted measurement noise, and a fast photodiode connected to an oscilloscope. The rise
- control electronics 3611 which controls the clamping laser 365 in order to compensate
- the high-speed electronic control of the clamping laser diode 365 enables the overshoot and undershoot to
- optical power was less than lOO ⁇ s for both cases.
- the EDFA 360 when pumped with the ASE source 310 and when using the
- Figure 47 shows an amplifying optical device 470 comprising a first port 479, a
- a JAC fibre 472 comprising a first end 475 and a second end 476, a
- the JAC fibre 472 may be any of the JAC fibres described herein.
- the JAC fibre 472 is JAC fibre 300 which is ring-doped with Ytterbium.
- the ends 475, 476 are preferably sealed and cleaved as described with
- the fibre 474 is preferably an optical fibre configured to be singlemoded at 980nm.
- Pump radiation 478 is coupled from the laser diode 311 which
- the pump radiation excites the Ytterbium ions, and radiation is thereupon
- the amplifying optical device 470 can be configured as an ASE source (see Figure 31) or a
- the amplifying optical device 470 can also be configured as an
- optical amplifier for amplifying signals having a wavelength where the JAC fibre 472 provides gain.
- Figure 48 shows an amplifying optical device 480 comprising a pump module 481,
- the pump module 481 can comprise the laser diode
- the pump module 481 can comprise the pump module
- the input beam 482 can be in free space, or more preferably, be guided by a high-
- numerical optical fibre such as a JAC fibre having low attenuation at the pump wavelength.
- Such a JAC fibre can be similar to JAC fibre 472 but without the rare-earth dopant.
- thin-film filter 483 can comprise graded refractive index (GRIN) lenses.
- GRIN graded refractive index
- the pump wavelength is preferably 915nm
- the pump wavelength is preferably 915nm
- dichroic mirror 484 preferably has a low attenuation for the pump radiation, and has a high
- the amplifying optical device 480 is particularly useful for amplifying signals having wavelengths around 976nm to
- the amplifying optical device as drawn is a 980nm optical amplifier.
- the first port 486 can be the input port of the optical amplifier, in which case the optical amplifier is
- the second port 487 can be the input port, in which case the
- optical amplifier is being co-pumped.
- Figure 49 shows an arrangement 490 comprising a pump source 491, the amplifying optical device 480 configured as an optical amplifier, a coupler 492, and a
- plurality of optical amplifiers 493 each comprising an input port 494, an output port 495,
- the pump source 491 can be a 980nm semiconductor laser diode,
- the coupler 492 can comprise at least one
- optical amplifiers 493 can be any optical amplifiers 493 that can be configured in planar optics.
- the optical amplifiers 493 can be any optical amplifiers 493 that can be configured in planar optics.
- Figure 50 shows a preform assembly 500 comprising a preform 501, a plurality of
- the preform 501 is a solid rods 502, a plurality of capillaries 503, and an outer jacket 504.
- the preform comprises a core 5 and a cladding 6.
- the core 5 may be rare-earth doped.
- the capillaries 503 are chosen to maximize the fill ratio, that is, to ensure
- outer jacket 504 to have the correct size, or adjusting their diameters by etching, by
- preform 501 is
- MCND modified chemical vapour deposition
- the capillaries 503 have thin walls in order to increase the volume fraction of air to glass
- volume fraction results in increased numerical aperture of the cladding of the resulting
- Figure 51 shows a cross-section of the JAC fibre 510 that is drawn from the preform assembly 500.
- the fibre 510 comprises longitudinally extending holes.511.
- Figure 52 shows a preform assembly 520 comprising a non-circular preform 521, rods 522, capillaries 523, and an outer jacket 524.
- the non circular preform 521 can be
- the rods 522 can be stress applying rods
- the stress applying rods may also be doped
- the amplifying fibres 510, 530 can be single mode or multimode depending on the
- Figures 51 and 53 show two types of amplifying optical fibres that can be drawn from the preform assemblies 500 and 520 respectively. However, many different designs
- capillaries can be sealed prior to the
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Lasers (AREA)
- Semiconductor Lasers (AREA)
- Optical Couplings Of Light Guides (AREA)
Abstract
Description
Claims
Applications Claiming Priority (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0126007 | 2001-10-30 | ||
GB0126007A GB0126007D0 (en) | 2001-10-30 | 2001-10-30 | An optical light source |
GB0203146 | 2002-02-08 | ||
GB0203146A GB0203146D0 (en) | 2002-02-08 | 2002-02-08 | An optical light source |
GB0222622A GB0222622D0 (en) | 2002-09-28 | 2002-09-28 | An optical light source |
GB0222622 | 2002-09-28 | ||
PCT/GB2002/004912 WO2003038486A2 (en) | 2001-10-30 | 2002-10-30 | An optical light source |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1440495A2 true EP1440495A2 (en) | 2004-07-28 |
Family
ID=27256307
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP02772580A Withdrawn EP1440495A2 (en) | 2001-10-30 | 2002-10-30 | An optical light source |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP1440495A2 (en) |
AU (1) | AU2002337338A1 (en) |
CA (1) | CA2465522A1 (en) |
WO (1) | WO2003038486A2 (en) |
Families Citing this family (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6885683B1 (en) | 2000-05-23 | 2005-04-26 | Imra America, Inc. | Modular, high energy, widely-tunable ultrafast fiber source |
US6751241B2 (en) | 2001-09-27 | 2004-06-15 | Corning Incorporated | Multimode fiber laser gratings |
US7414780B2 (en) | 2003-06-30 | 2008-08-19 | Imra America, Inc. | All-fiber chirped pulse amplification systems |
US7257302B2 (en) * | 2003-06-03 | 2007-08-14 | Imra America, Inc. | In-line, high energy fiber chirped pulse amplification system |
US7403689B2 (en) | 2003-11-19 | 2008-07-22 | Corning Incorporated | Active photonic band-gap optical fiber |
WO2005091029A2 (en) * | 2004-03-19 | 2005-09-29 | Crystal Fibre A/S | Optical coupler devices, methods of their production and use |
FI20045308A (en) * | 2004-08-26 | 2006-02-27 | Corelase Oy | Optical fiber amplifier with modal discrimination of amplification |
EP1662624B1 (en) * | 2004-11-30 | 2009-04-22 | Universite Des Sciences Et Technologies De Lille | Passively Q-switched ytterbium-doped solid-state laser with samarium-doped fibre as saturable absorber |
US7496260B2 (en) | 2007-03-27 | 2009-02-24 | Imra America, Inc. | Ultra high numerical aperture optical fibers |
JP4243327B2 (en) * | 2007-04-06 | 2009-03-25 | 株式会社フジクラ | Photonic band gap fiber and fiber amplifier |
WO2010060435A1 (en) * | 2008-11-28 | 2010-06-03 | Nkt Photonics A/S | Improved cladding-pumped optical waveguide |
FR2951878B1 (en) * | 2009-10-22 | 2011-11-25 | Centre Nat Rech Scient | SYSTEM FOR GENERATING DOPED MICROSTRUCTURE OPTICAL FIBER OPTICAL POLYCHROMATIC LIGHT |
CN107946891B (en) * | 2017-12-14 | 2019-09-17 | 湖北工业大学 | A kind of high-power ultraviolet solid-state laser |
CN114026750A (en) * | 2019-06-05 | 2022-02-08 | 恩耐公司 | Aiming laser insensitive to optical fiber laser |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5363463A (en) * | 1982-08-06 | 1994-11-08 | Kleinerman Marcos Y | Remote sensing of physical variables with fiber optic systems |
US4780877A (en) * | 1985-07-26 | 1988-10-25 | Polaroid Corporation | Optical fiber laser |
US4782491A (en) * | 1987-04-09 | 1988-11-01 | Polaroid Corporation | Ion doped, fused silica glass fiber laser |
GB2239983A (en) * | 1989-12-22 | 1991-07-17 | Univ Southampton | Optical fibre laser |
US4967416A (en) * | 1990-02-28 | 1990-10-30 | The United States Of America As Represented By The Secretary Of The Navy | Thulium-doped fluorozirconate fiber laser pumped by a diode laser source |
US5121460A (en) * | 1991-01-31 | 1992-06-09 | The Charles Stark Draper Lab., Inc. | High-power mode-selective optical fiber laser |
US5530709A (en) * | 1994-09-06 | 1996-06-25 | Sdl, Inc. | Double-clad upconversion fiber laser |
US5710786A (en) * | 1995-08-25 | 1998-01-20 | Sdl, Inc. | Optical fibre laser pump source for fibre amplifiers |
GB9625231D0 (en) * | 1996-12-04 | 1997-01-22 | Univ Southampton | Optical amplifiers & lasers |
US5907652A (en) * | 1997-09-11 | 1999-05-25 | Lucent Technologies Inc. | Article comprising an air-clad optical fiber |
US6061369A (en) * | 1999-06-01 | 2000-05-09 | Corning Incorporated | Wavelength selectable fiber laser system |
-
2002
- 2002-10-30 EP EP02772580A patent/EP1440495A2/en not_active Withdrawn
- 2002-10-30 AU AU2002337338A patent/AU2002337338A1/en not_active Abandoned
- 2002-10-30 WO PCT/GB2002/004912 patent/WO2003038486A2/en not_active Application Discontinuation
- 2002-10-30 CA CA002465522A patent/CA2465522A1/en not_active Abandoned
Non-Patent Citations (1)
Title |
---|
See references of WO03038486A2 * |
Also Published As
Publication number | Publication date |
---|---|
CA2465522A1 (en) | 2003-05-08 |
WO2003038486A2 (en) | 2003-05-08 |
WO2003038486A3 (en) | 2003-08-21 |
AU2002337338A1 (en) | 2003-05-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6836607B2 (en) | Cladding-pumped 3-level fiber laser/amplifier | |
US8270070B2 (en) | Multi-fibre arrangement for high power fibre lasers and amplifiers | |
JP3247292B2 (en) | Optical communication system | |
US6370180B2 (en) | Semiconductor-solid state laser optical waveguide pump | |
US5790722A (en) | High power optical fiber amplifier/laser system | |
EP2791719B1 (en) | Multi-core erbium-doped fiber amplifier | |
EP1430572A1 (en) | Multimode fiber laser gratings | |
US11509110B2 (en) | Broadband Ho-doped optical fiber amplifier | |
EP1440495A2 (en) | An optical light source | |
US7599406B2 (en) | Fiber ring laser | |
Mélin et al. | Power efficient all-fiberized 12-core erbium/ytterbium doped optical amplifier | |
US7038844B2 (en) | High power 938 nanometer fiber laser and amplifier | |
KR20110065305A (en) | Double clad fiber laser device | |
Simonneau et al. | High-power air-clad photonic crystal fiber cladding-pumped EDFA for WDM applications in the C-band | |
Forster et al. | Single-End-Pumped Tm 3+: Ho 3+-Codoped all-Fiber Laser at 2120 nm | |
Du et al. | FIFO-less Core-pumped Multicore Erbium-doped Fiber Amplifier with Hybrid Passive Components | |
CN217115138U (en) | Optical fiber laser | |
Jung et al. | Fully integrated SDM amplifiers | |
Bousselet et al. | dBm output power from an engineered cladding-pumped Yb-free EDFA for L-band WDM applications | |
Goodno et al. | Single-frequency, single-mode emission at 2040 nm from a 600-W thulium-doped fiber amplifier chain | |
Leplingard et al. | High-power (+ 24 dBm) double-clad erbium-doped fibre amplifier for WDM applications in the C-band (1528 nm-1562 nm) | |
Lawrence et al. | Versatile waveguide design for optical amplification | |
Blaize et al. | 1, 55 µm DFB laser integrated on Erbium doped phosphate glass substrate | |
Wang et al. | Research on broadband wavelength tunable erbium-doped fiber ring laser | |
Zhang et al. | A novel L-band multi-wavelength erbium-doped fiber ring laser |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20040425 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SK TR |
|
AX | Request for extension of the european patent |
Extension state: AL LT LV MK RO SI |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: SELVAS-AGUILAR, ROMEO Inventor name: RENAUD, CYRIL Inventor name: NILSSON, LARS JOHAN ALBINSSON Inventor name: RICHARDSON, DAVID Inventor name: SAHU, JAYAUNTA KUMAR Inventor name: HORLEY, RAY Inventor name: CODEMARD, CHRISTOPHE Inventor name: MOORE, JONATHAN Inventor name: TURNER, PAUL Inventor name: GODFREY, IAN Inventor name: YLA-JARKKO, KALLE Inventor name: GRUDININ, ANATOLY Inventor name: SHAIFUL, ALAM |
|
RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: SELVAS-AGUILAR, ROMEO Inventor name: RENAUD, CYRIL Inventor name: NILSSON, LARS JOHAN ALBINSSON Inventor name: RICHARDSON, DAVID Inventor name: SAHU, JAYAUNTA KUMAR Inventor name: HORLEY, RAY Inventor name: CODEMARD, CHRISTOPHE Inventor name: MOORE, JONATHAN Inventor name: TURNER, PAUL Inventor name: GODFREY, IAN Inventor name: YLA-JARKKO, KALLE Inventor name: GRUDININ, ANATOLY Inventor name: SHAIFUL, ALAM |
|
17Q | First examination report despatched |
Effective date: 20050107 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
18D | Application deemed to be withdrawn |
Effective date: 20050502 |