CA1311635C - Optical device - Google Patents
Optical deviceInfo
- Publication number
- CA1311635C CA1311635C CA000565350A CA565350A CA1311635C CA 1311635 C CA1311635 C CA 1311635C CA 000565350 A CA000565350 A CA 000565350A CA 565350 A CA565350 A CA 565350A CA 1311635 C CA1311635 C CA 1311635C
- Authority
- CA
- Canada
- Prior art keywords
- layer
- waveguide
- refractive index
- diffraction grating
- optical
- 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.)
- Expired - Fee Related
Links
- 230000003287 optical effect Effects 0.000 title claims abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 4
- 239000010409 thin film Substances 0.000 claims abstract description 3
- 239000013307 optical fiber Substances 0.000 abstract description 3
- 239000000835 fiber Substances 0.000 description 4
- 239000010408 film Substances 0.000 description 3
- 238000005530 etching Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 244000166490 Tetrameles nudiflora Species 0.000 description 1
- MWPLVEDNUUSJAV-UHFFFAOYSA-N anthracene Chemical compound C1=CC=CC2=CC3=CC=CC=C3C=C21 MWPLVEDNUUSJAV-UHFFFAOYSA-N 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
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
- G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
- G02B6/02061—Grating external to the fibre and in contact with the fibre, e.g. evanescently coupled, gratings applied to the fibre end
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/011—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour in optical waveguides, not otherwise provided for in this subclass
-
- 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
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/0675—Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers
-
- 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
- G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
- G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
- G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
- G02B6/29316—Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide
- G02B6/29317—Light guides of the optical fibre type
-
- 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
- H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
- H01S5/12—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers
- H01S5/125—Distributed Bragg reflector [DBR] lasers
Abstract
ABSTRACT
An optical device comprises an optical waveguide, such as a single mode optical fibre (11), underlying a first layer (20) of material, such as a thin film, which has a refractive index higher than the refractive index of the waveguide (11) and which forms a planar waveguide capable of supporting and a guiding at least one propagation mode of a higher order than, but matching the phase velocity of, the propagation mode or modes in the underlying waveguide. A reflection diffraction grating (4) is provided on or adjacent to the surface of the first layer (2) remote from the waveguide (11). The arrangement is such that an optical signal which is coupled from the waveguide (11) into the first layer (2) is reflected by the reflection diffraction grating (4) and is coupled back into the waveguide.
An optical device comprises an optical waveguide, such as a single mode optical fibre (11), underlying a first layer (20) of material, such as a thin film, which has a refractive index higher than the refractive index of the waveguide (11) and which forms a planar waveguide capable of supporting and a guiding at least one propagation mode of a higher order than, but matching the phase velocity of, the propagation mode or modes in the underlying waveguide. A reflection diffraction grating (4) is provided on or adjacent to the surface of the first layer (2) remote from the waveguide (11). The arrangement is such that an optical signal which is coupled from the waveguide (11) into the first layer (2) is reflected by the reflection diffraction grating (4) and is coupled back into the waveguide.
Description
``"~ 131 1635 ~T CAqE No.A23647 ~P N0. 0~06P
~h~
The lnvention rRla~Qs to an optlcal de~ice.
Th~re 1~ currently conYiderable in~erest in ~he u~e o~
high~refl~lvlty gratin~ filters for use as fe~dback and filt~rlng elements in, for ~xample, fihr~ lasers. At pre~nt, the generation of a high re~l~c~$vlty grating fil~er involves etching gra~ings formed in photore~ on ~op o~ polished direction~ uplers and providing an overlyin~ layer o~ oil with ~ re~rac~ive index ~atch~ng th~t of the underlying waveguide. ~n ~xample of thi~ i8 de~ribed in "Hl~h ReflectiYity ~onomo8e~Fihre G~tin~
Fil~ers" ~lectronic~ Letters, 13~h March l9B~, Vol. 22, No. ~, p~ges 3~ 43.
The gener~tion of ~hese ~ilter~ invol~es complex fabrication procedurea which are difflault to circum~ent and expenslve~
In accordance with ~he present invention, an optical devlce comprises an opt~cal waveguide underly~ng a fir~t la~e~ o~ ~aterial whlch has a refr~ctlv~ inde~ higher th~n ~h~ effe~tive refractive index of the waveguide an~ ~hich forms a planar wavequide capable of supporting and guiding at lea~ one pr~paga~ion mode of a higher order than, but matchin~ ~he phase velo~ity o~, thQ propagation mo~e or modss in the underlying waveguld~; and a diffraction ~rating provided on or ad~acen~ to at least on~ sur~a~e of ~: :
:
: : ~
:
`
:
:
the first layer, the arrangement baing such tha~ an optical signal with a selected wavelength which is coupled from the waveguide into the first layer impinges on the diffraction grating and is coupled back into the waveguide.
This invention provides an alternative approach to the etching of gratings directly onto the waveguide by applying the grating in a high index overlay structure.
The wavelength which is selected can be predetermined but in some cases the refractive index of the first layer of material could be tuned. This might be possible if the material of the first layer was electro-optic (e.g. a liquid crystal).
In most cases several optical modes will be coupled into the first layer but only one will be reflected. However, in other cases just one optical mode might be coupled in the first layer.
The diffraction grating is preferably provided on or adjacent to the surface of the first layer remote from the waveguide. This enables the diffraction grating to be made independently of the remainder of the device. However it could be provided on the surface adjacent the waveguide or two diffraction gratings could be provided, one on each surface.
Preferably, the device further comprises a second ~5 layer (or superstrate) overlying the first layer with the surface of the second layer facing the first layer being provided with the diffraction grating.
Typically, the second layer will form a non-guiding superstrate having a substantially planar surface and a refractive index which iS lower than the effective refractive index of the first layer for a given mode of propagation.
The first layer and the superstrate are preferably in intimate contact. This obviates the need for ; 35 an index :: :
:,~
:
, , -: ::
- ~` 131 1635 matchlng liquld be~ween the fir~t layer and ~he superstra~e. The w~vegulde and th~ first lay~r ~re al~o pref~rably in intlm~te ~ontact but may ~e sp~ced a s~al~
dl~tance apart. ~or eff~c~ive ~oupling, close pro~mity of ~h~ wav~guid~ an~ f~rst layer are required for strong field couplin~, providing a degree of l~teral confine~ent of th~ field in the ~ir5t layer.
Th~ waveguide con~eniently ~omprises an optlcal fi~re, and is pref~ra~ly an optical slngle mode fibre.
In another form of the inventivn, ~he waveguide may compri~ a wav~yuide assocla~ed With, or ~orming part of, an integrated op~lcs device.
The optic~l device accordin~ to the inYention may be usad in a wid~ variety of applications ~Ut 15 par~icul~rly sulted for use as f~edbhck or filterlng ele~ents in fLbr~
lasers.
The diffraction gratillg pre~erably co~pri3es a ~eflection di~actlon gratin~ although a phase gratlng wi~hout a reflec~ive lay~r could also b~ u6ed.
Reflection at the diffractivn g~tlng W~ll occur when the Bragg condltion is satiBfiedt that i~
~h~
The lnvention rRla~Qs to an optlcal de~ice.
Th~re 1~ currently conYiderable in~erest in ~he u~e o~
high~refl~lvlty gratin~ filters for use as fe~dback and filt~rlng elements in, for ~xample, fihr~ lasers. At pre~nt, the generation of a high re~l~c~$vlty grating fil~er involves etching gra~ings formed in photore~ on ~op o~ polished direction~ uplers and providing an overlyin~ layer o~ oil with ~ re~rac~ive index ~atch~ng th~t of the underlying waveguide. ~n ~xample of thi~ i8 de~ribed in "Hl~h ReflectiYity ~onomo8e~Fihre G~tin~
Fil~ers" ~lectronic~ Letters, 13~h March l9B~, Vol. 22, No. ~, p~ges 3~ 43.
The gener~tion of ~hese ~ilter~ invol~es complex fabrication procedurea which are difflault to circum~ent and expenslve~
In accordance with ~he present invention, an optical devlce comprises an opt~cal waveguide underly~ng a fir~t la~e~ o~ ~aterial whlch has a refr~ctlv~ inde~ higher th~n ~h~ effe~tive refractive index of the waveguide an~ ~hich forms a planar wavequide capable of supporting and guiding at lea~ one pr~paga~ion mode of a higher order than, but matchin~ ~he phase velo~ity o~, thQ propagation mo~e or modss in the underlying waveguld~; and a diffraction ~rating provided on or ad~acen~ to at least on~ sur~a~e of ~: :
:
: : ~
:
`
:
:
the first layer, the arrangement baing such tha~ an optical signal with a selected wavelength which is coupled from the waveguide into the first layer impinges on the diffraction grating and is coupled back into the waveguide.
This invention provides an alternative approach to the etching of gratings directly onto the waveguide by applying the grating in a high index overlay structure.
The wavelength which is selected can be predetermined but in some cases the refractive index of the first layer of material could be tuned. This might be possible if the material of the first layer was electro-optic (e.g. a liquid crystal).
In most cases several optical modes will be coupled into the first layer but only one will be reflected. However, in other cases just one optical mode might be coupled in the first layer.
The diffraction grating is preferably provided on or adjacent to the surface of the first layer remote from the waveguide. This enables the diffraction grating to be made independently of the remainder of the device. However it could be provided on the surface adjacent the waveguide or two diffraction gratings could be provided, one on each surface.
Preferably, the device further comprises a second ~5 layer (or superstrate) overlying the first layer with the surface of the second layer facing the first layer being provided with the diffraction grating.
Typically, the second layer will form a non-guiding superstrate having a substantially planar surface and a refractive index which iS lower than the effective refractive index of the first layer for a given mode of propagation.
The first layer and the superstrate are preferably in intimate contact. This obviates the need for ; 35 an index :: :
:,~
:
, , -: ::
- ~` 131 1635 matchlng liquld be~ween the fir~t layer and ~he superstra~e. The w~vegulde and th~ first lay~r ~re al~o pref~rably in intlm~te ~ontact but may ~e sp~ced a s~al~
dl~tance apart. ~or eff~c~ive ~oupling, close pro~mity of ~h~ wav~guid~ an~ f~rst layer are required for strong field couplin~, providing a degree of l~teral confine~ent of th~ field in the ~ir5t layer.
Th~ waveguide con~eniently ~omprises an optlcal fi~re, and is pref~ra~ly an optical slngle mode fibre.
In another form of the inventivn, ~he waveguide may compri~ a wav~yuide assocla~ed With, or ~orming part of, an integrated op~lcs device.
The optic~l device accordin~ to the inYention may be usad in a wid~ variety of applications ~Ut 15 par~icul~rly sulted for use as f~edbhck or filterlng ele~ents in fLbr~
lasers.
The diffraction gratillg pre~erably co~pri3es a ~eflection di~actlon gratin~ although a phase gratlng wi~hout a reflec~ive lay~r could also b~ u6ed.
Reflection at the diffractivn g~tlng W~ll occur when the Bragg condltion is satiBfiedt that i~
2~P
~he~e ~ i~ the ~ree-space wavelength, ne is tlle e~ctlve r~fr~ti~e inde~ of the guld~d mode in the ~irst lay~r, and O ls th~ p~riod of ~he diffractlon gr~tlng.
A ~ull discu6sion of the coupllng of op~ical mode~
hetween the waveguide and the fir~t layer is contained i31 "~xpo~ed-~ore ~ingl~-Mode Flbre Channel-~ropp~n~ Filter Using a High-Index Overlay Waveguid~" published in Optics Le~ters, April 1~87, vol 12, No.4, ~rom p~ge 284.
The r~fractlve ind~x ~n) of a ma~erial is unde~t~od he~ein to ~e the ~ulk refr~tive index of the mate~ial as determined ~y means of an Abhe refracto~ter, for exa~ple. The e~ective re~rac~ive index ~ne) i~ th~ ra~io `
: :: ..
' .;
, : ' ; ' of the spee~ o~ ligh~ in v~cuo ~ o the phase velocl~y (vp) of ~he guld~d ~ode con~e~ne~.
The refrac~ive ~ndQx of th~ first laye~ is at l~t 1/o, and pr~erably a~ le~t 1~/o, greater than the effective refractive i~dex of the waveguide~ However, lt ha~ been calcul~ed ~hat ef~icient coupl~n~ will ~e obtain~d even in cases where the refractlve inde~ of the first lay~r 1B 60/o higher than the effective reEra¢tlv~ lnde% of the wav~g~ide~
An example o~ an optlcal d~vice in accordance wlth the pre~en~ inventlon w~ll now he deYcribed ~lth refer~n~a to th~ accompanying drawing~, ~n wnlch~
Fi~ure 1 ls ~ ~chema~lc sec~lonal vie~ through the de~ice; ~nd, Pigure 2A and 2B illu6tra~e the tran~mi~ion and refl~ction re~pon~e respectively of the device.
. The optical device ~hown in Flgure 1 comprise0 a ; poll~had opt~cal ~lbre half-coupler 1 in~rporatin~ ~n opt~cal single mode f$bre wave gulde, 11 and ~nd~rlylng a fir~t layer formed by a th~n ~ 2. ~ substrate in the form of a fused ~l$ca ~l~d& 3 ~8 ~ounted on top o~ the ~llm Z a~d a spac~r 5. ~he e~posed flbre length i8 approxlmately S20 ~. Also, ~109e proxlmity o~ flbre and ovorlay ensures qood coupling. Optical fibre hal~-couplers o~ thls type are de~cribed, for exampl2, by . N~yar, "In~ optlcs~ ds. ~ol~inq and Ulrlch, Sprlnger ~orie~ ln Opt. Sc.,Vol 48, 8prlnger Verlag lg~5. The con~tru~tlon of the polishea h~lf-coupler~ a~ such ls not 4f the e~sence o~ the pre~ent inventi~n and hence need not be ~iscu~sed h~ ln dqtail. ~or the presen~ pu~po~s lt ::: 18 suff~cl~nt to:note ~ha~ the fibre ~l wa~ stAndard ~ritish Telecom type ~B~ single mode ~ibr~, th~t ~he radius of flbre curvature in the halE-coupler wa3 25cnl, ~.
:
:
.
and that the c~addlng of the fih~e 11 waR ~emov~d by polishing to withln 1~ of ~he fibre core 12~
Optical fibre~ such a~ those used in the fabrication o~ the hal~-c~uplers have an effectlve refr~ctive ind~x o~
~pproxim~tely 1.45 at a wavelength of nominally l.5~m.
The thin film over~ay 2 is a ~hin ov~rlay of proprietary re~ra~lve lndex liquid, e~g. ~ suppliQd bg Cargille ~nc. o~ 55 Cedar Grove, New J~rsay, U~A~
The surPAce of the ~uh~trate 3 which ~ng~ge~ the thin fllm ~v~rlay 2 iB provia~d With a dlffrac~ion grating 4 which, ln one examp~e, has 24ao line~/mm~ Thi~ is pressed ont~ ~he coupler 1 ~ith an in~eractlon len~th L with the film overlay 2 o~ a~ouk 3 mm. The refractl~e index o~ the th~n film overl~y 2 was, in this example, chosen to be 1.60.
In an experiment to test the responRe of the device, white light was in~ected into the optlcal fibre 11 and a ~eek ~a~k raflecte~ signal R was observed At a wavelength of 1.20~9 mlcron, but only when the thicknes~ (t) of t~
film 2 wa~ adiu~ted to glve Ghannel d~opping at that wa~elength~ Figure 2A illustrates the variation in inten~iky ~f the transmik~ed signal T with wavelength wh~le ~igur~ 2~ illu~trate~ ~he variation in intenslty of the r~flected ~lgnal R w~h ~velength. It will be 3e~n frvm Figllre 2 th~t there is a peak 1n the re~lected signal intensity at 1~009 ~icron.
In other exa~ples (not shown), the spa~er 5 could he much thinner or even omit~ed.
'`;
:~:
:' ' ~ ` ~ ' .
. .
-: , : '
~he~e ~ i~ the ~ree-space wavelength, ne is tlle e~ctlve r~fr~ti~e inde~ of the guld~d mode in the ~irst lay~r, and O ls th~ p~riod of ~he diffractlon gr~tlng.
A ~ull discu6sion of the coupllng of op~ical mode~
hetween the waveguide and the fir~t layer is contained i31 "~xpo~ed-~ore ~ingl~-Mode Flbre Channel-~ropp~n~ Filter Using a High-Index Overlay Waveguid~" published in Optics Le~ters, April 1~87, vol 12, No.4, ~rom p~ge 284.
The r~fractlve ind~x ~n) of a ma~erial is unde~t~od he~ein to ~e the ~ulk refr~tive index of the mate~ial as determined ~y means of an Abhe refracto~ter, for exa~ple. The e~ective re~rac~ive index ~ne) i~ th~ ra~io `
: :: ..
' .;
, : ' ; ' of the spee~ o~ ligh~ in v~cuo ~ o the phase velocl~y (vp) of ~he guld~d ~ode con~e~ne~.
The refrac~ive ~ndQx of th~ first laye~ is at l~t 1/o, and pr~erably a~ le~t 1~/o, greater than the effective refractive i~dex of the waveguide~ However, lt ha~ been calcul~ed ~hat ef~icient coupl~n~ will ~e obtain~d even in cases where the refractlve inde~ of the first lay~r 1B 60/o higher than the effective reEra¢tlv~ lnde% of the wav~g~ide~
An example o~ an optlcal d~vice in accordance wlth the pre~en~ inventlon w~ll now he deYcribed ~lth refer~n~a to th~ accompanying drawing~, ~n wnlch~
Fi~ure 1 ls ~ ~chema~lc sec~lonal vie~ through the de~ice; ~nd, Pigure 2A and 2B illu6tra~e the tran~mi~ion and refl~ction re~pon~e respectively of the device.
. The optical device ~hown in Flgure 1 comprise0 a ; poll~had opt~cal ~lbre half-coupler 1 in~rporatin~ ~n opt~cal single mode f$bre wave gulde, 11 and ~nd~rlylng a fir~t layer formed by a th~n ~ 2. ~ substrate in the form of a fused ~l$ca ~l~d& 3 ~8 ~ounted on top o~ the ~llm Z a~d a spac~r 5. ~he e~posed flbre length i8 approxlmately S20 ~. Also, ~109e proxlmity o~ flbre and ovorlay ensures qood coupling. Optical fibre hal~-couplers o~ thls type are de~cribed, for exampl2, by . N~yar, "In~ optlcs~ ds. ~ol~inq and Ulrlch, Sprlnger ~orie~ ln Opt. Sc.,Vol 48, 8prlnger Verlag lg~5. The con~tru~tlon of the polishea h~lf-coupler~ a~ such ls not 4f the e~sence o~ the pre~ent inventi~n and hence need not be ~iscu~sed h~ ln dqtail. ~or the presen~ pu~po~s lt ::: 18 suff~cl~nt to:note ~ha~ the fibre ~l wa~ stAndard ~ritish Telecom type ~B~ single mode ~ibr~, th~t ~he radius of flbre curvature in the halE-coupler wa3 25cnl, ~.
:
:
.
and that the c~addlng of the fih~e 11 waR ~emov~d by polishing to withln 1~ of ~he fibre core 12~
Optical fibre~ such a~ those used in the fabrication o~ the hal~-c~uplers have an effectlve refr~ctive ind~x o~
~pproxim~tely 1.45 at a wavelength of nominally l.5~m.
The thin film over~ay 2 is a ~hin ov~rlay of proprietary re~ra~lve lndex liquid, e~g. ~ suppliQd bg Cargille ~nc. o~ 55 Cedar Grove, New J~rsay, U~A~
The surPAce of the ~uh~trate 3 which ~ng~ge~ the thin fllm ~v~rlay 2 iB provia~d With a dlffrac~ion grating 4 which, ln one examp~e, has 24ao line~/mm~ Thi~ is pressed ont~ ~he coupler 1 ~ith an in~eractlon len~th L with the film overlay 2 o~ a~ouk 3 mm. The refractl~e index o~ the th~n film overl~y 2 was, in this example, chosen to be 1.60.
In an experiment to test the responRe of the device, white light was in~ected into the optlcal fibre 11 and a ~eek ~a~k raflecte~ signal R was observed At a wavelength of 1.20~9 mlcron, but only when the thicknes~ (t) of t~
film 2 wa~ adiu~ted to glve Ghannel d~opping at that wa~elength~ Figure 2A illustrates the variation in inten~iky ~f the transmik~ed signal T with wavelength wh~le ~igur~ 2~ illu~trate~ ~he variation in intenslty of the r~flected ~lgnal R w~h ~velength. It will be 3e~n frvm Figllre 2 th~t there is a peak 1n the re~lected signal intensity at 1~009 ~icron.
In other exa~ples (not shown), the spa~er 5 could he much thinner or even omit~ed.
'`;
:~:
:' ' ~ ` ~ ' .
. .
-: , : '
Claims (11)
1. An optical device comprising an optical waveguide underlying a first layer of material which has a refractive index higher than the effective refractive index of the waveguide and which forms a planar waveguide capable of supporting and guiding at least one propagation mode of a higher order than, but matching the phase velocity of, the propagation mode or modes in the underlying waveguide;
and a diffraction grating provided on or adjacent to at least one surface of the first layer, the arrangement being such that an optical signal which is coupled from the waveguide into the first layer impinges on the diffraction grating and is coupled back to the waveguide.
and a diffraction grating provided on or adjacent to at least one surface of the first layer, the arrangement being such that an optical signal which is coupled from the waveguide into the first layer impinges on the diffraction grating and is coupled back to the waveguide.
2. A device according to claim 1, wherein the diffraction grating is provided on or adjacent to the surface of the first layer remote from the waveguide.
3. A device according to claim 2, further comprising a second layer overlying the first layer with the surface of the second layer facing the first layer providing the diffraction grating.
4. A device according to claim 3, wherein the second layer forms a non-guiding superstrate having a substantially planar surface and a refractive index which is lower than the effective refractive index of the first layer for a given mode of propagation.
5. A device according to claim 4, wherein the first layer and the superstrate are in intimate contact.
6. A device according to any of claims 1, 2, 3, 4 or 5 wherein the waveguide and the first layer are in intimate contact.
7. A device according to any of claims 1, 2, 3, 4 or 5, wherein the first layer comprises a thin film.
8. A device according to any of claims 1, 2, 3, 4 or 5, wherein the diffraction grating comprises a reflection diffraction grating.
9. A device according to any of claims 1, 2, 3, 4 or 5, wherein the refractive index of the first layer is at least 1% greater than the effective refractive index of the waveguide.
10. A device according to any of claims 1, 2, 3, 4 or 5, wherein the refractive index of the first layer is at least 15% greater than the effective refractive index of the waveguide.
11. A device according to any of claims 1, 2, 3, 4 or 5, wherein the refractive index of the first layer is at least 60% higher than the effective refractive index of the waveguide.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB878710067A GB8710067D0 (en) | 1987-04-28 | 1987-04-28 | Optical device |
| GB8710067 | 1987-04-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1311635C true CA1311635C (en) | 1992-12-22 |
Family
ID=10616507
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000565350A Expired - Fee Related CA1311635C (en) | 1987-04-28 | 1988-04-28 | Optical device |
Country Status (9)
| Country | Link |
|---|---|
| US (1) | US4881791A (en) |
| EP (1) | EP0289332B1 (en) |
| JP (1) | JPH01503573A (en) |
| AT (1) | ATE110857T1 (en) |
| AU (1) | AU598129B2 (en) |
| CA (1) | CA1311635C (en) |
| DE (1) | DE3851254T2 (en) |
| GB (1) | GB8710067D0 (en) |
| WO (1) | WO1988008548A1 (en) |
Families Citing this family (31)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB8706929D0 (en) * | 1987-03-24 | 1987-04-29 | British Telecomm | Optical coupling device |
| AT397442B (en) * | 1989-02-21 | 1994-04-25 | Zehetner Johann | Processing method for optical waveguides designed with a capillary channel, and an optical component equipped with such an optical waveguide |
| EP0431527B1 (en) * | 1989-12-04 | 1995-03-15 | Canon Kabushiki Kaisha | Optical coupling device using wavelength selective optical coupler |
| US5048913A (en) * | 1989-12-26 | 1991-09-17 | United Technologies Corporation | Optical waveguide embedded transverse spatial mode discrimination filter |
| US5018814A (en) * | 1990-02-13 | 1991-05-28 | Physical Optics Corporation | Broadband single-mode optical coupler |
| DE69128786T2 (en) * | 1990-06-06 | 1998-08-20 | Kol Ohr Corp | Tunable light source and fiber optic systems with tunable light source |
| GB2254183B (en) * | 1991-03-27 | 1995-01-18 | Marconi Gec Ltd | An amplifier/filter combination |
| GB9119734D0 (en) * | 1991-09-16 | 1991-10-30 | British Telecomm | Optical grating device |
| DE4231113A1 (en) * | 1992-09-17 | 1994-03-24 | Bosch Gmbh Robert | Integrated optical circuit with a Bragg structure |
| US5625729A (en) * | 1994-08-12 | 1997-04-29 | Brown; Thomas G. | Optoelectronic device for coupling between an external optical wave and a local optical wave for optical modulators and detectors |
| US5809188A (en) * | 1997-03-14 | 1998-09-15 | National Science Council | Tunable optical filter or reflector |
| US6952504B2 (en) * | 2001-12-21 | 2005-10-04 | Neophotonics Corporation | Three dimensional engineering of planar optical structures |
| US6011881A (en) * | 1997-12-29 | 2000-01-04 | Ifos, Intelligent Fiber Optic Systems | Fiber-optic tunable filter |
| US6718097B2 (en) * | 2000-07-18 | 2004-04-06 | Kvh Industries, Inc. | Method of incorporating optical material into an optical fiber |
| ATE527104T1 (en) * | 2000-10-26 | 2011-10-15 | Neophotonics Corp | MULTI-LAYER OPTICAL STRUCTURES |
| US20040120649A1 (en) * | 2002-12-20 | 2004-06-24 | Motorola, Inc. | Optical coupling interface for optical waveguide and optical fiber |
| EP2077132A1 (en) | 2008-01-02 | 2009-07-08 | Boehringer Ingelheim Pharma GmbH & Co. KG | Dispensing device, storage device and method for dispensing a formulation |
| EP2662472B1 (en) | 2009-03-31 | 2019-02-27 | Boehringer Ingelheim International Gmbh | Method for coating a surface of a component |
| US9265910B2 (en) | 2009-05-18 | 2016-02-23 | Boehringer Ingelheim International Gmbh | Adapter, inhalation device, and nebulizer |
| PE20130036A1 (en) | 2009-11-25 | 2013-02-03 | Boehringer Ingelheim Int | Nebulizer |
| EP2504051B1 (en) | 2009-11-25 | 2019-09-04 | Boehringer Ingelheim International GmbH | Nebulizer |
| US10016568B2 (en) | 2009-11-25 | 2018-07-10 | Boehringer Ingelheim International Gmbh | Nebulizer |
| JP5874724B2 (en) | 2010-06-24 | 2016-03-02 | ベーリンガー インゲルハイム インターナショナル ゲゼルシャフト ミット ベシュレンクテル ハフツング | Nebulizer |
| EP2694220B1 (en) | 2011-04-01 | 2020-05-06 | Boehringer Ingelheim International GmbH | Medical device comprising a container |
| US9827384B2 (en) | 2011-05-23 | 2017-11-28 | Boehringer Ingelheim International Gmbh | Nebulizer |
| WO2013152894A1 (en) | 2012-04-13 | 2013-10-17 | Boehringer Ingelheim International Gmbh | Atomiser with coding means |
| PL2835146T3 (en) | 2013-08-09 | 2021-04-06 | Boehringer Ingelheim International Gmbh | Nebulizer |
| EP3030298B1 (en) | 2013-08-09 | 2017-10-11 | Boehringer Ingelheim International GmbH | Nebulizer |
| EP3139984B1 (en) | 2014-05-07 | 2021-04-28 | Boehringer Ingelheim International GmbH | Nebulizer |
| ES2957901T3 (en) | 2014-05-07 | 2024-01-29 | Boehringer Ingelheim Int | Container and indicator device and nebulizer |
| WO2015169732A1 (en) | 2014-05-07 | 2015-11-12 | Boehringer Ingelheim International Gmbh | Container, nebulizer and use |
Family Cites Families (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3891302A (en) * | 1973-09-28 | 1975-06-24 | Western Electric Co | Method of filtering modes in optical waveguides |
| US3898585A (en) * | 1974-01-14 | 1975-08-05 | Ibm | Leaky corrugated optical waveguide device |
| DE2442723A1 (en) * | 1974-09-06 | 1976-03-18 | Siemens Ag | CONTROLLABLE ELECTRO-OPTICAL LATTICE COUPLER |
| JPS5355132A (en) * | 1976-10-29 | 1978-05-19 | Nec Corp | Coupling method of optical fibers |
| CA1108902A (en) * | 1978-06-15 | 1981-09-15 | R. Ian Macdonald | Wavelength selective optical coupler |
| US4268116A (en) * | 1979-10-26 | 1981-05-19 | Optelecom Incorporated | Method and apparatus for radiant energy modulation in optical fibers |
| US4386822A (en) * | 1980-10-10 | 1983-06-07 | The Leland Stanford Junior University | Polarizer and method |
| US4583818A (en) * | 1983-08-08 | 1986-04-22 | Gte Laboratories Incorporated | Optical device with surface plasmons |
| US4531809A (en) * | 1983-09-08 | 1985-07-30 | Gte Laboratories Incorporated | Optical waveguide coupling device |
| JPS60121404A (en) * | 1983-12-05 | 1985-06-28 | Nippon Telegr & Teleph Corp <Ntt> | Optical demultiplexer |
| JPS60156020A (en) * | 1984-01-25 | 1985-08-16 | Sumitomo Metal Mining Co Ltd | Optical branching element |
| GB2161648B (en) * | 1984-07-12 | 1988-02-03 | Stc Plc | Semiconductor laser |
| GB2170016B (en) * | 1984-12-19 | 1989-04-05 | Plessey Co Plc | Improvements in or relating to modulators |
| JPS6215506A (en) * | 1985-07-15 | 1987-01-23 | ザ・ボ−ド・オブ・トラステイ−ズ・オブ・ザ・レランド・スタンフオ−ド・ジユニア・ユニバ−シテイ | Apparatus for selectively controlling light propagation in optical system |
| US4695123A (en) * | 1985-08-20 | 1987-09-22 | Litton Systems, Inc. | Cutoff polarizer and method |
| US4828350A (en) * | 1986-01-17 | 1989-05-09 | The Board Of Trustees Of The Leland Stanford Junior University | Fiber optic mode selector |
| US4737007A (en) * | 1986-02-24 | 1988-04-12 | American Telephone And Telegraph Company, At&T Bell Laboratories | Narrow-band wavelength selective optical coupler |
-
1987
- 1987-04-28 GB GB878710067A patent/GB8710067D0/en active Pending
-
1988
- 1988-04-28 US US07/288,036 patent/US4881791A/en not_active Expired - Fee Related
- 1988-04-28 DE DE3851254T patent/DE3851254T2/en not_active Expired - Fee Related
- 1988-04-28 AT AT88303888T patent/ATE110857T1/en not_active IP Right Cessation
- 1988-04-28 AU AU16882/88A patent/AU598129B2/en not_active Ceased
- 1988-04-28 CA CA000565350A patent/CA1311635C/en not_active Expired - Fee Related
- 1988-04-28 EP EP88303888A patent/EP0289332B1/en not_active Expired - Lifetime
- 1988-04-28 WO PCT/GB1988/000333 patent/WO1988008548A1/en unknown
- 1988-04-28 JP JP63503838A patent/JPH01503573A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01503573A (en) | 1989-11-30 |
| US4881791A (en) | 1989-11-21 |
| ATE110857T1 (en) | 1994-09-15 |
| DE3851254D1 (en) | 1994-10-06 |
| AU1688288A (en) | 1988-12-02 |
| EP0289332B1 (en) | 1994-08-31 |
| DE3851254T2 (en) | 1995-01-26 |
| EP0289332A1 (en) | 1988-11-02 |
| GB8710067D0 (en) | 1987-06-03 |
| WO1988008548A1 (en) | 1988-11-03 |
| AU598129B2 (en) | 1990-06-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1311635C (en) | Optical device | |
| US6449404B1 (en) | Optical switch | |
| US6507684B2 (en) | Optical microcavity resonator system | |
| AU780632B2 (en) | Optoelectronic and photonic devices | |
| CA1085203A (en) | Optical fiber tap | |
| US5444723A (en) | Optical switch and Q-switched laser | |
| US6839479B2 (en) | Optical switch | |
| EP0686867A1 (en) | All fiber in-line optical isolator | |
| JP2005508021A (en) | Optical junction apparatus and method using optical power transverse transmission | |
| EP0234127B1 (en) | Optical coupler | |
| EP1236251B1 (en) | Waveguide laser device | |
| CA2539851A1 (en) | Optical functional waveguide, optical modulator, arrayed waveguide grating, and dispersion compensation circuit | |
| US4722583A (en) | Modulators | |
| JP3490745B2 (en) | Composite optical waveguide type optical device | |
| Ilchenko et al. | Tunability and synthetic lineshapes in high-Q optical whispering-gallery modes | |
| US4182544A (en) | Resonant multiplexer-demultiplexer for optical data communication systems | |
| EP0649038A1 (en) | Optical waveguide mirror | |
| US4995689A (en) | Waveguide scanner | |
| JPS62182726A (en) | Liquid crystal swiching unit with optical fiber | |
| CN106772798B (en) | Reflection-type narrow band filter based on waveguide Bragg grating | |
| CA3038944C (en) | Glass ferrule coupling of in-line fiber taps and fiber cladding waveguides | |
| JP2002333602A (en) | Optical element including photonic crystalline structure and optical control method | |
| WO2000028352A2 (en) | System for information/data interface to optical fibers and method of fabrication | |
| Oh et al. | Integrated-optic focal-spot intensity modulator using electrooptic polymer waveguide | |
| CN1319770A (en) | Method and equipment for alignment of waveguide and device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |