CA1313909C - Semiconducteur device assembly - Google Patents
Semiconducteur device assemblyInfo
- Publication number
- CA1313909C CA1313909C CA000595110A CA595110A CA1313909C CA 1313909 C CA1313909 C CA 1313909C CA 000595110 A CA000595110 A CA 000595110A CA 595110 A CA595110 A CA 595110A CA 1313909 C CA1313909 C CA 1313909C
- Authority
- CA
- Canada
- Prior art keywords
- device assembly
- laser
- light emitting
- assembly according
- optical processing
- 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
Classifications
-
- 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
- H01S5/14—External cavity lasers
- H01S5/141—External cavity lasers using a wavelength selective device, e.g. a grating or etalon
-
- 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
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/105—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling the mutual position or the reflecting properties of the reflectors of the cavity, e.g. by controlling the cavity length
- H01S3/1055—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling the mutual position or the reflecting properties of the reflectors of the cavity, e.g. by controlling the cavity length one of the reflectors being constituted by a diffraction grating
-
- 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
- H01S5/02—Structural details or components not essential to laser action
- H01S5/022—Mountings; Housings
- H01S5/02208—Mountings; Housings characterised by the shape of the housings
-
- 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
- H01S5/02—Structural details or components not essential to laser action
- H01S5/022—Mountings; Housings
- H01S5/0225—Out-coupling of light
- H01S5/02251—Out-coupling of light using optical fibres
Abstract
ABSTRACT
An external cavity laser assembly in which the laser chip is within a hermetically sealed package and the external cavity is outside the hermetic package. A collimating lens in a screw threaded mounting is disposed outside the hermetic package, the screw thread permitting focussing.
The cavity is tuned by rotation and translation of a grating, the position of which is electrically controlled via piezoelectric stacks. Thermal expansion of the stacks is compensated by mounting the grating on a rod of suitable material (e.g. ceramic) which also serves to reduce the cavity length whilst allowing maximum piezoextension. In a second embodiment the assembly is a tunable laser amplifier, with a grating being driven in a similar manner to provide the tuning.
An external cavity laser assembly in which the laser chip is within a hermetically sealed package and the external cavity is outside the hermetic package. A collimating lens in a screw threaded mounting is disposed outside the hermetic package, the screw thread permitting focussing.
The cavity is tuned by rotation and translation of a grating, the position of which is electrically controlled via piezoelectric stacks. Thermal expansion of the stacks is compensated by mounting the grating on a rod of suitable material (e.g. ceramic) which also serves to reduce the cavity length whilst allowing maximum piezoextension. In a second embodiment the assembly is a tunable laser amplifier, with a grating being driven in a similar manner to provide the tuning.
Description
13.~3~9 BE~ICONDUC~02 ~VIC~ A~S~L~
Thl~ invention Pelates to ~emiconductor devi~ a66Qmblies, and ln particula~ to e~t~rnal cavity ~em~condu~tor laser pac~a~Q~ and ~aser a~pllfier packa~ ultab~ for in~orporation into an optical co~municatlons s~tem, and to apparat~B for electrlcallg controlling mo~able optical procsssin~ element~ wlthin a devic~ packa~e.
Coheren~ optical communlcation~ ~y~em~ p4tentially offer greater 5e~3itivity, but ~or detection ln such sys~m~ it is ne~es~ary to have a cont~nuou~ly tunahle, n~rrow line lo w$d~h, fiinyle mo~e source. Such a sourc~ i~ an ex~ernal cavity la~r in ~hich on~ ~e~conducto~ laser ~acet ~ -anti-re~lection co~ed to r~duc~ int~r~al ~d~a~k and a selec~d ~avelen~th ~ cted b~ck in~o ~h~ la~er ln order to ~ti~ulate do~$~nce of that wav~length ~n th~
laser output. l'he r~1¢4tlon 1~ u#ually Prom an extern~lly located dif~rac~ion gratlng ~or~ing khe ~xt~rnal ca~ity. In order to tun~ to dlfer~nt wavalength~ th~ gratlng can b~ rotated to pre~ent a d~f~er~nt period or the grating can be mov~d ~ longitud~nall~ ~o alter the cav~ty length. When the grating iB ro~at~d the passband of re~lected w~vel~ngtn~
~hanges and thu~ if rot~ed ~uffi~lently the pa~and may be~om~ cent~ed on a different mode or ~com~ cen~ralised b~t~een t~o ~od~s. ~han~in~ the ~avit~ length al~ers the mode positlons, and BO a mode centred on the gratlng pa6sband ~11 move over thfl pas~band Wl~h v~ tion in longitudinal gratlng po~itlon~ ~hus it ~3 pos~ible by slmultaneou~ ro~ation and longi~udinal ~ovement to shlft the waveleng~h o~ the grat~ng passband tby rotation) bu~
., ~31~
remain centred on the same mode (by changing the cavity length) and avoid mode hopping. It is necessary to avoid mode changes during detection because the control circuits are tuned to fine adjustment and cannot cope with the comparatively massive changes that occur with mode change.
In laboratory test equipment, adjustments to the grating position have been made manually by micrometer screw adjustment and the components are all movable and realignable. While such an arrangement is satisfactory for investigative purposes, for implementation in actual communications systems it is nesessary to have automatic control, a durable package that is permanently aligned and a hermetically sealed environment for the laser.
Similar problems arise in packaging receiver elements such as tunable laser amplifiers~
The present invention is directed towards providing practical packaging including elements requiring harmetic sealing, for systems use.
Accordingly a first aspect of the invention provides a device assembly comprising a light emitting element and an optical processiny element, apparatus for mounting the optical processing element in a spaced relationship to the light emitting element, the light emitting element being disposed within a hermetically sealed package having a transparent portion for the passage of light to the optical processing element disposed outside the hermetically sealed package, wherein the mounting apparatus comprises a plurality of piezoelectric stacks '3 ` ' $~
~P~
- 2a -arranged such that selPctive elongation and/or contraction of the piezeoelectric stacks provides S rotational and translational movement of the optical processing element thereby modi~ying the spaced relationship.
Another aspect of the invention is a device assembly comprising a light emitting element and an optical processing element disposed to intercept light emanating from the li~ht emitting element, the optical processing element and tha light emitting element being spaced apart by plural piezoelectric supports and at least one other support, the supports providing compensating thexmal expansion and contraction movements so that thermally induced change in the spacing in a first direction caused by the piezoelectric supports is compensated by thermally induced change in the spacing in an opposite second direction caused by the other support, whereby the spacing between the optical processing element and the light emitting element is maintained at a more constant dimension as a function of device assembly temperature.
Another aspect of the invention is a device assembly comprising a semiconductor laser, a grating defining an external cavity for the laser, the laser being disposed within its hermetically sealed package having a transparent portion for the passage of light to the grating disposed outside the hermetically sealed package, the grating being supported and spaced from the transparent portion by a plurality of at least three independently controllable piezoelectric stacks disposed , ., ~313~09 - 2b -SQ that selective elongated and/or contraction of the piezoelectric stacks can provide rotational and translational movement of the grating thereby modifying S its spaced relationship to the laser.
Another aspect of the invention is a device assembly comprising a semiconductor laser, a tunable filter, the laser being disposed within a hermetically sealed package having a transparent portion for the passage of light to the tunable filter disposed outside the hermetically sealed package, the tunable filter being supported and spaced from the transparent portion by a plurality of at least three independently controllable piezeoelectric stacks disposed so that selective elongation and/or contraction of the piezoelectric stacks can provide rotational and translational movemsnt of the filter thereby modifying its spaced relationship to the laser.
.. ..
,3~
~~ 3~ ~. 313~09 Anotl~er asp~t ~ th~ inwntlon provld~s ap~aratu~ for moving an opti~al proce~sin~ elem~n~ withln a devi~e assembly, the app~ratu~ comprlsing ~ plurali~y o~
pia~oele~t~c Rtacks arranged sllch that 6~ ive elonyation and/or ~ontrac~ion of th~ pi~oel~ctric ~tac~s provides ro~atlonal and t~nsl~tional m~vement of the optical proce~61n~ element.
In a p~e~e~red embodiment ~he light emitting elemen~ i3 a s~miconductor la~er and the opti~l processlnq el~ment i5 a grating defining an e~ternal cavity. ~nother embo~imen$
comprl~s a la~er amplifie~ with a tuna~le fllter. the filter m~y be of reflection or transmis6ion ~ype~
The lnv~nt~on i~ now ~e~cribed by way o~ example wi~h re~erenGe 'C0 th~ accompanyirlg d~awing~ ln ~hich:
Figure 1 i~ ~ plan Vi9~ of a i~ir6S embodim~nt o~ ~he inventlon:
~gu~ an end vie~ o~ ~ ~rating all~nment ~ount o~
~h~ embodiment of ~lgu~e 1;
~lgure 3 iæ a ~ide vlew o~ the embodiment o~ FigurQ 1.
Flgur~ 4 i8 il ~econd embodiment o~ the inven'cion; and Figur~ 5 i~ a further r~odification of the in~ention.
Xe~rrlng to Figure l, the ~ssembly compriQes a las~r chip 1 that ~8 hermetically seale~ in a chip pa~Xage 2. One output fac~ o~ the laser i6 coupled to a fibre 3 w~thin the h~r~etic packag~ 2, the f~br~ pa~8ing out o~ thR
p~ ag~ through a fibrc ~kag~ h~rmetic seal of kno~rn typ~.
~ 4 - 13~3909 The ~ond output ~a~&t o~ the las~r i~ ~nti-r~flection co~ted and dire~:ted to~ard~ a ~indow 4 ln the hermetic ge w~ll after whi~h the light p~9!~5 thro~gh a len~ 5 and on t~ a gratin~ 6. Th~ arr~ng~men~ depart~ fro~ the exp~cted ~rr~n~ement o~ n~3ting tha entir~ ass~bly S including the external cavity within a her~etlc pac~age, and it ha~ the adv~n~age of alleviatin~ materiaîs outga~s~ng probl~s. No~ve~ to collimat~ the beam it ~s necessary to have a len~ ~nd the lenses previously u~ed ~or such purpo6es, selfoc or spherical len6es, ~re of Yery o short focal ~ength (u~ually a f~w hundred micron~) and need to be located clo~e to the laser ~cet. Xnstead of u~ilising ~he usual type o~ lens a much lon~er focal l~ngth lenRI of the order of 3 mm, i5 eluployed and ~n this ~ay it i8 pos~ible to loc~te th~ len~ ou'c~id~ th2 h~metic lS p~kage and avoid ~he a~iynment cons~rain~s that ~ould be ~mpo~ed in ~tte~pting to align ~nd ~ocus a laser, lens and window within a hermetic packag~ or in aliqn~ng ~he laser with a lenq mounted in ~he packagQ wall~ ~h~ ~elected arrangem~nt ~nable~ the l~s~r ~:o ~2 loca~ed w~ll aw~ ~o~
~he hs~etic pac~a9e wall, t:here~y ~ing ~ssembl~
handlin~, and the len~, being lo~ated ~:Fter the windo~, can lncorpora'ce window a~errati~n ~o~pen6ation and be indep~n~en~ly ali~ned an~ focus~ed wlth the la~er pacl~
2s ~he lens is mountad in a screw thr~aded hold~ ~ tha~
screw~ int~ ~n end plate 9; the end pla~e and hol~er are - pre~rably m~d~ o~ Kovar ~o minimi~ ~ovemellt due ko thermal expans~on~ In order to adjust ~h~ lan3 fo~us ~l~h respec~ to the laser the holder 8 is ro~ated ~n l;he screw thread~ Once the corr~c'c focusing is achiev~d it i5 nece9sary, for ~ptl~um long~term sta~ility, ~o lock the len~ in po~i~ion ~nd thls is dorl~ ~y welding ~he scre~
threaded holder in the ead plate 9. During the lens 1313~09 ad~ustm~nt phase lt 1~ de~ir~ble not to have any ~l~c~
between th~ thr~ads o~ the holdar ~ and end pla~s g, and a ti~htly ~itting thread i~ achi~ved ~y gold plating the ~threads o~ ~he holder. Other substanceQ may he u~ed to provide the tight screw ~ ing, ~ut g~ld i~ pre~erred a~
it main~ain~ me~al to metal contact be~we~n th~ hold~r and end plate which i3 ad~ntageou~ at the welding staq~. If opti~um long-tern~ ~ta~ility i~ no~ r~qulred, the lsn~ n~ed not be welded in pla~. Provi~ion may the~ be ~ade to adiu~ the len~ posi~ion ~rom wi~hout~ thus ~a~llltatin~
o device set-up.
~lec~rical fine con~rol of th~ gratin~ po~ition i5 provlded by piezoelectric st~cks 10, the ~nds of which engage with mech~nical adjus~ment ~c~ews 11. Thre~
piezoe~ectric stacks are proYlded as ~hown by the ad~ustment s~rew loc~ions in ~he end ~ie~ ~hown in ~iyure Z although it is pos~le to utlli~e ~ dif~rent mlm~er o~
st~ck6. t~ith t`ne arrangem~nt ~hown, ~rati~g rotation 15 a~hleved by ~longation or contraction of She stack~
al1gned With ~crews 11' whil~ plvotinq abollt th~ ~t~t~k a~ign~a ~ith scrQws 11"~ A~justn~ent to cavity len~th i~
achi~ved by simul'caneous e1onga~on or con~ra~tion o~ all three ~tacks 1~. The scr~ws 11 provide coar~r adju~tment ~or initi~l ~etting up. The ~diu~t~ent ranges are of the 4rde~ of 3 r~tatlon and 700 micron~ to ~ ~m in ca~lty length for khe 8~r~5, and 2 millir~dians and 15 micron~
with ~he piezoe~ectri~ sta ks. The range o~ e~ectrical adjustment with an overall cavity leng~h o~ 2 centim~tres provides tuning of ~ore than 50 5H~.
3~
In ordu to a~hieve suita~le mode discri~inatiorl the cav~ty l~ngth needs to be of the order of ~ cm or I~!BS as mentioned above. ~owev~r in order ~o ~et 6u$~i~iént - 6 - ~ 3~39~
mov~ment ~o~ the tunlny range the pia~oele~ric 5~a~:~t8 al~o need to b~ of the order o~ 2 centi~etr~ or m~re in leng~h, and ~o lt is not po~sl~ls to mount: the gr~lng on the end o~ ~he stacks wi~hout increa~ing the cavity l~ngth and losing mod~ al~rlminat~on. Th~re~ore ~he arran~emenk showT in the dr~win~s was devi~ed, wl~h th~ grating supported orl a rod 12 ~hat pro~e~t~ inwardly ~etw~en th~
piezoelectric st~ks tQward~ th~ la~r. ~he rod 12 i~
provided wlth ~ collar 13 to which a ~lange 14 ~arr~ing the ad~u~tment screws 11 is attached. ~he ~d~ust~ent ~crew~ hear again~t the ends of the ple~o~lectrlc stack~
and the grating i8 moved by virttle o~ the plezoeleckri~
s'cack and screw 11 mov~nlent being ~r~nsr~lt~ed to th~ rod 12 v~a the flange 14~ ~his arrangement, by suitabl~
~hoic~ of materials, (~or ex~mple a ceramic rod 12) als~
~5 enables compensat~on ~or the~mal expansi~n with expansion o~ ~he st:acXs bein~ co~pens~ted ~ expan~ion in th~
oppo~it~ dir~tion of the ceramic rod.
A f~rthar eaturQ o~ the packaqe i~ that it is su~stantially symmetric~l about the opti~al axis, ra~h~r ~han following the normal stacked ~ror~ base arranyem~n~
and thl3 al~o redllces ~hermal misalignment prohl~ms.
Th~ p~rformance of the ahove-descri~ed ext~rnal ca~y ~5 laser can be ~urther lmpro~ed by the add1~ion o~ an e~alorl.
The et~lon, positioned in the opti~al path ~etween the len~ and ~he grating, ~hould preferably have a free ~pectral ~ange ~the interval ~etwe~n adiacent ~ransmission p~ak~) wider than the bandwldth of ~he gr~tlng~ Tl~ning o~
the etalon i6 achieved elther by rot~lon or, ~here lt i8 possible, by phy ically moYing one of the etalon re1ectvrs r01ative to th~ other~ The etalon ~ay consis~
o~ a eoli~ tran6parent body,glass for exampl~, with a pair - 7 - . 13~39~9 ~ ~lgh rBfla~tivl~y ~ ts, Such an e~alon ~ould b~
t~n~d hy rotation, ~pt~mally fr~/to ~UBt Of~ nor~al incidence with the laser be~m. An ~lt~rn~tiYe et~l~n structure comprise~ a Fabry-P~rot ~tructure in ~hich a pair of high ~efle~tivity mirrors f~ce each o~her~ Wi~h su~h an etalon, tuning ~a~ he a~e~ed by moving one reflecto~ relative to the othe~, Pre~er~bly ~uch r~l~tive movemant 19 achieved by means of ~ p~o ele~n~, such as a ring~shaped piezo element. Such an etalon i~ al30 preferably aligned ~u~ o~ normal lnciden~e W~ he e laser beam.
If an ~talon i6 used, it becomes po~si~1e ~o u~ a gratln~
with a reduced number of lines-per-mill~m~tre~ ~h~l~ still achievin~ ~he same line~idth. ~o~ a glv~n ~mount o~
gratin~ ro~a~ion, a greater ~ver~ll tunln~ range is provided for a lower line ~per-m1lllmetre ~ount of a gr~ting~ ~n the present example, whera o~ ~ight use a l~00 llne~-per-mlllim~tre gra~ing wi~h~u~ an ~ on. one ml~ht use a gratlng ~i~h soo, 600 or fewer line~-per-m~llimetre, g~ing a tuning range potentially twi~e as wiae as ~ha~ available with the ~ine ~r~in~.
Th~ pric~ to be paid for th~ narrDw~r line~idth and~or gr~Qr tuning ~an~e ~hl~h r~ul~ ~ro~ ~he u~e o~ a~
etalon is in ~he increas~d eDmplexi$y in the tunlng proce~s. GQnarally wi~ such an ~rrange~en~, b~th the grating a~d ~he etalon ~ill have ~o be moved~ ~h~re ~he et~lon i~ piezo-~unable, as i5 the case wi~h the above mentl~ned Fabry-Perot device, it b~comes readily pos~i~le ~0 tune ths ~talon and ~ove the grating ~imultaneou~ly, hen~e ensurlng a narro~ linewld~h ou~put (de~er~lned by the e~alon tran~mission window) while avoidlng mode h~pping.
~ ~ ~ 31 39~9 The paeka~3 ds~cr1b~d abov~ ~ay ha m~diflad ~or use a~ a laser amplifier package a8 shown in Figur~ 4~ In ~nis in~tance both facet~ o~ ~h~ la~er ~re ~ntl~r~fle~tlon coated and ~he qratin~ i8 anql~d with re~p~ct to ~he optlcal ~th ~o that the re~l~ct~d light d~Q~ not re-enter the laser but i~ directed on to a prl~m 14 ~nd then a PIN
pho~odiode 15~ alterna~ively an in-line ~ er or gra~ing m~y be u~ed ~ the po~tion ~hown in Fi~ur~ 5~ In this latter ~n~ance the ~ilter or gratln~ ~upport is ~odified to provid~ a contitluous optic~ th~
The gr~ting or fllter may be u~d betwe~n spher~c~ ns~
a~ described in our cop~n~n~ appli~a~ion PC~/~B~7/00715 the lens 5 or the len~ ~ and window ~ may bs replaced by the ~irst ~ph~rical lens. ~hen a reflection grating i6 ~5 u~ed the g~a~ing i~ optl~ally in~erpos~d bet~en ~h~
lenses but not phy31cally 80. A la~er amplifler p~ckage with such a gra~lng or filter ~ay b~ u~ o provide tuning for a tunable receiYer.
Thl~ invention Pelates to ~emiconductor devi~ a66Qmblies, and ln particula~ to e~t~rnal cavity ~em~condu~tor laser pac~a~Q~ and ~aser a~pllfier packa~ ultab~ for in~orporation into an optical co~municatlons s~tem, and to apparat~B for electrlcallg controlling mo~able optical procsssin~ element~ wlthin a devic~ packa~e.
Coheren~ optical communlcation~ ~y~em~ p4tentially offer greater 5e~3itivity, but ~or detection ln such sys~m~ it is ne~es~ary to have a cont~nuou~ly tunahle, n~rrow line lo w$d~h, fiinyle mo~e source. Such a sourc~ i~ an ex~ernal cavity la~r in ~hich on~ ~e~conducto~ laser ~acet ~ -anti-re~lection co~ed to r~duc~ int~r~al ~d~a~k and a selec~d ~avelen~th ~ cted b~ck in~o ~h~ la~er ln order to ~ti~ulate do~$~nce of that wav~length ~n th~
laser output. l'he r~1¢4tlon 1~ u#ually Prom an extern~lly located dif~rac~ion gratlng ~or~ing khe ~xt~rnal ca~ity. In order to tun~ to dlfer~nt wavalength~ th~ gratlng can b~ rotated to pre~ent a d~f~er~nt period or the grating can be mov~d ~ longitud~nall~ ~o alter the cav~ty length. When the grating iB ro~at~d the passband of re~lected w~vel~ngtn~
~hanges and thu~ if rot~ed ~uffi~lently the pa~and may be~om~ cent~ed on a different mode or ~com~ cen~ralised b~t~een t~o ~od~s. ~han~in~ the ~avit~ length al~ers the mode positlons, and BO a mode centred on the gratlng pa6sband ~11 move over thfl pas~band Wl~h v~ tion in longitudinal gratlng po~itlon~ ~hus it ~3 pos~ible by slmultaneou~ ro~ation and longi~udinal ~ovement to shlft the waveleng~h o~ the grat~ng passband tby rotation) bu~
., ~31~
remain centred on the same mode (by changing the cavity length) and avoid mode hopping. It is necessary to avoid mode changes during detection because the control circuits are tuned to fine adjustment and cannot cope with the comparatively massive changes that occur with mode change.
In laboratory test equipment, adjustments to the grating position have been made manually by micrometer screw adjustment and the components are all movable and realignable. While such an arrangement is satisfactory for investigative purposes, for implementation in actual communications systems it is nesessary to have automatic control, a durable package that is permanently aligned and a hermetically sealed environment for the laser.
Similar problems arise in packaging receiver elements such as tunable laser amplifiers~
The present invention is directed towards providing practical packaging including elements requiring harmetic sealing, for systems use.
Accordingly a first aspect of the invention provides a device assembly comprising a light emitting element and an optical processiny element, apparatus for mounting the optical processing element in a spaced relationship to the light emitting element, the light emitting element being disposed within a hermetically sealed package having a transparent portion for the passage of light to the optical processing element disposed outside the hermetically sealed package, wherein the mounting apparatus comprises a plurality of piezoelectric stacks '3 ` ' $~
~P~
- 2a -arranged such that selPctive elongation and/or contraction of the piezeoelectric stacks provides S rotational and translational movement of the optical processing element thereby modi~ying the spaced relationship.
Another aspect of the invention is a device assembly comprising a light emitting element and an optical processing element disposed to intercept light emanating from the li~ht emitting element, the optical processing element and tha light emitting element being spaced apart by plural piezoelectric supports and at least one other support, the supports providing compensating thexmal expansion and contraction movements so that thermally induced change in the spacing in a first direction caused by the piezoelectric supports is compensated by thermally induced change in the spacing in an opposite second direction caused by the other support, whereby the spacing between the optical processing element and the light emitting element is maintained at a more constant dimension as a function of device assembly temperature.
Another aspect of the invention is a device assembly comprising a semiconductor laser, a grating defining an external cavity for the laser, the laser being disposed within its hermetically sealed package having a transparent portion for the passage of light to the grating disposed outside the hermetically sealed package, the grating being supported and spaced from the transparent portion by a plurality of at least three independently controllable piezoelectric stacks disposed , ., ~313~09 - 2b -SQ that selective elongated and/or contraction of the piezoelectric stacks can provide rotational and translational movement of the grating thereby modifying S its spaced relationship to the laser.
Another aspect of the invention is a device assembly comprising a semiconductor laser, a tunable filter, the laser being disposed within a hermetically sealed package having a transparent portion for the passage of light to the tunable filter disposed outside the hermetically sealed package, the tunable filter being supported and spaced from the transparent portion by a plurality of at least three independently controllable piezeoelectric stacks disposed so that selective elongation and/or contraction of the piezoelectric stacks can provide rotational and translational movemsnt of the filter thereby modifying its spaced relationship to the laser.
.. ..
,3~
~~ 3~ ~. 313~09 Anotl~er asp~t ~ th~ inwntlon provld~s ap~aratu~ for moving an opti~al proce~sin~ elem~n~ withln a devi~e assembly, the app~ratu~ comprlsing ~ plurali~y o~
pia~oele~t~c Rtacks arranged sllch that 6~ ive elonyation and/or ~ontrac~ion of th~ pi~oel~ctric ~tac~s provides ro~atlonal and t~nsl~tional m~vement of the optical proce~61n~ element.
In a p~e~e~red embodiment ~he light emitting elemen~ i3 a s~miconductor la~er and the opti~l processlnq el~ment i5 a grating defining an e~ternal cavity. ~nother embo~imen$
comprl~s a la~er amplifie~ with a tuna~le fllter. the filter m~y be of reflection or transmis6ion ~ype~
The lnv~nt~on i~ now ~e~cribed by way o~ example wi~h re~erenGe 'C0 th~ accompanyirlg d~awing~ ln ~hich:
Figure 1 i~ ~ plan Vi9~ of a i~ir6S embodim~nt o~ ~he inventlon:
~gu~ an end vie~ o~ ~ ~rating all~nment ~ount o~
~h~ embodiment of ~lgu~e 1;
~lgure 3 iæ a ~ide vlew o~ the embodiment o~ FigurQ 1.
Flgur~ 4 i8 il ~econd embodiment o~ the inven'cion; and Figur~ 5 i~ a further r~odification of the in~ention.
Xe~rrlng to Figure l, the ~ssembly compriQes a las~r chip 1 that ~8 hermetically seale~ in a chip pa~Xage 2. One output fac~ o~ the laser i6 coupled to a fibre 3 w~thin the h~r~etic packag~ 2, the f~br~ pa~8ing out o~ thR
p~ ag~ through a fibrc ~kag~ h~rmetic seal of kno~rn typ~.
~ 4 - 13~3909 The ~ond output ~a~&t o~ the las~r i~ ~nti-r~flection co~ted and dire~:ted to~ard~ a ~indow 4 ln the hermetic ge w~ll after whi~h the light p~9!~5 thro~gh a len~ 5 and on t~ a gratin~ 6. Th~ arr~ng~men~ depart~ fro~ the exp~cted ~rr~n~ement o~ n~3ting tha entir~ ass~bly S including the external cavity within a her~etlc pac~age, and it ha~ the adv~n~age of alleviatin~ materiaîs outga~s~ng probl~s. No~ve~ to collimat~ the beam it ~s necessary to have a len~ ~nd the lenses previously u~ed ~or such purpo6es, selfoc or spherical len6es, ~re of Yery o short focal ~ength (u~ually a f~w hundred micron~) and need to be located clo~e to the laser ~cet. Xnstead of u~ilising ~he usual type o~ lens a much lon~er focal l~ngth lenRI of the order of 3 mm, i5 eluployed and ~n this ~ay it i8 pos~ible to loc~te th~ len~ ou'c~id~ th2 h~metic lS p~kage and avoid ~he a~iynment cons~rain~s that ~ould be ~mpo~ed in ~tte~pting to align ~nd ~ocus a laser, lens and window within a hermetic packag~ or in aliqn~ng ~he laser with a lenq mounted in ~he packagQ wall~ ~h~ ~elected arrangem~nt ~nable~ the l~s~r ~:o ~2 loca~ed w~ll aw~ ~o~
~he hs~etic pac~a9e wall, t:here~y ~ing ~ssembl~
handlin~, and the len~, being lo~ated ~:Fter the windo~, can lncorpora'ce window a~errati~n ~o~pen6ation and be indep~n~en~ly ali~ned an~ focus~ed wlth the la~er pacl~
2s ~he lens is mountad in a screw thr~aded hold~ ~ tha~
screw~ int~ ~n end plate 9; the end pla~e and hol~er are - pre~rably m~d~ o~ Kovar ~o minimi~ ~ovemellt due ko thermal expans~on~ In order to adjust ~h~ lan3 fo~us ~l~h respec~ to the laser the holder 8 is ro~ated ~n l;he screw thread~ Once the corr~c'c focusing is achiev~d it i5 nece9sary, for ~ptl~um long~term sta~ility, ~o lock the len~ in po~i~ion ~nd thls is dorl~ ~y welding ~he scre~
threaded holder in the ead plate 9. During the lens 1313~09 ad~ustm~nt phase lt 1~ de~ir~ble not to have any ~l~c~
between th~ thr~ads o~ the holdar ~ and end pla~s g, and a ti~htly ~itting thread i~ achi~ved ~y gold plating the ~threads o~ ~he holder. Other substanceQ may he u~ed to provide the tight screw ~ ing, ~ut g~ld i~ pre~erred a~
it main~ain~ me~al to metal contact be~we~n th~ hold~r and end plate which i3 ad~ntageou~ at the welding staq~. If opti~um long-tern~ ~ta~ility i~ no~ r~qulred, the lsn~ n~ed not be welded in pla~. Provi~ion may the~ be ~ade to adiu~ the len~ posi~ion ~rom wi~hout~ thus ~a~llltatin~
o device set-up.
~lec~rical fine con~rol of th~ gratin~ po~ition i5 provlded by piezoelectric st~cks 10, the ~nds of which engage with mech~nical adjus~ment ~c~ews 11. Thre~
piezoe~ectric stacks are proYlded as ~hown by the ad~ustment s~rew loc~ions in ~he end ~ie~ ~hown in ~iyure Z although it is pos~le to utlli~e ~ dif~rent mlm~er o~
st~ck6. t~ith t`ne arrangem~nt ~hown, ~rati~g rotation 15 a~hleved by ~longation or contraction of She stack~
al1gned With ~crews 11' whil~ plvotinq abollt th~ ~t~t~k a~ign~a ~ith scrQws 11"~ A~justn~ent to cavity len~th i~
achi~ved by simul'caneous e1onga~on or con~ra~tion o~ all three ~tacks 1~. The scr~ws 11 provide coar~r adju~tment ~or initi~l ~etting up. The ~diu~t~ent ranges are of the 4rde~ of 3 r~tatlon and 700 micron~ to ~ ~m in ca~lty length for khe 8~r~5, and 2 millir~dians and 15 micron~
with ~he piezoe~ectri~ sta ks. The range o~ e~ectrical adjustment with an overall cavity leng~h o~ 2 centim~tres provides tuning of ~ore than 50 5H~.
3~
In ordu to a~hieve suita~le mode discri~inatiorl the cav~ty l~ngth needs to be of the order of ~ cm or I~!BS as mentioned above. ~owev~r in order ~o ~et 6u$~i~iént - 6 - ~ 3~39~
mov~ment ~o~ the tunlny range the pia~oele~ric 5~a~:~t8 al~o need to b~ of the order o~ 2 centi~etr~ or m~re in leng~h, and ~o lt is not po~sl~ls to mount: the gr~lng on the end o~ ~he stacks wi~hout increa~ing the cavity l~ngth and losing mod~ al~rlminat~on. Th~re~ore ~he arran~emenk showT in the dr~win~s was devi~ed, wl~h th~ grating supported orl a rod 12 ~hat pro~e~t~ inwardly ~etw~en th~
piezoelectric st~ks tQward~ th~ la~r. ~he rod 12 i~
provided wlth ~ collar 13 to which a ~lange 14 ~arr~ing the ad~u~tment screws 11 is attached. ~he ~d~ust~ent ~crew~ hear again~t the ends of the ple~o~lectrlc stack~
and the grating i8 moved by virttle o~ the plezoeleckri~
s'cack and screw 11 mov~nlent being ~r~nsr~lt~ed to th~ rod 12 v~a the flange 14~ ~his arrangement, by suitabl~
~hoic~ of materials, (~or ex~mple a ceramic rod 12) als~
~5 enables compensat~on ~or the~mal expansi~n with expansion o~ ~he st:acXs bein~ co~pens~ted ~ expan~ion in th~
oppo~it~ dir~tion of the ceramic rod.
A f~rthar eaturQ o~ the packaqe i~ that it is su~stantially symmetric~l about the opti~al axis, ra~h~r ~han following the normal stacked ~ror~ base arranyem~n~
and thl3 al~o redllces ~hermal misalignment prohl~ms.
Th~ p~rformance of the ahove-descri~ed ext~rnal ca~y ~5 laser can be ~urther lmpro~ed by the add1~ion o~ an e~alorl.
The et~lon, positioned in the opti~al path ~etween the len~ and ~he grating, ~hould preferably have a free ~pectral ~ange ~the interval ~etwe~n adiacent ~ransmission p~ak~) wider than the bandwldth of ~he gr~tlng~ Tl~ning o~
the etalon i6 achieved elther by rot~lon or, ~here lt i8 possible, by phy ically moYing one of the etalon re1ectvrs r01ative to th~ other~ The etalon ~ay consis~
o~ a eoli~ tran6parent body,glass for exampl~, with a pair - 7 - . 13~39~9 ~ ~lgh rBfla~tivl~y ~ ts, Such an e~alon ~ould b~
t~n~d hy rotation, ~pt~mally fr~/to ~UBt Of~ nor~al incidence with the laser be~m. An ~lt~rn~tiYe et~l~n structure comprise~ a Fabry-P~rot ~tructure in ~hich a pair of high ~efle~tivity mirrors f~ce each o~her~ Wi~h su~h an etalon, tuning ~a~ he a~e~ed by moving one reflecto~ relative to the othe~, Pre~er~bly ~uch r~l~tive movemant 19 achieved by means of ~ p~o ele~n~, such as a ring~shaped piezo element. Such an etalon i~ al30 preferably aligned ~u~ o~ normal lnciden~e W~ he e laser beam.
If an ~talon i6 used, it becomes po~si~1e ~o u~ a gratln~
with a reduced number of lines-per-mill~m~tre~ ~h~l~ still achievin~ ~he same line~idth. ~o~ a glv~n ~mount o~
gratin~ ro~a~ion, a greater ~ver~ll tunln~ range is provided for a lower line ~per-m1lllmetre ~ount of a gr~ting~ ~n the present example, whera o~ ~ight use a l~00 llne~-per-mlllim~tre gra~ing wi~h~u~ an ~ on. one ml~ht use a gratlng ~i~h soo, 600 or fewer line~-per-m~llimetre, g~ing a tuning range potentially twi~e as wiae as ~ha~ available with the ~ine ~r~in~.
Th~ pric~ to be paid for th~ narrDw~r line~idth and~or gr~Qr tuning ~an~e ~hl~h r~ul~ ~ro~ ~he u~e o~ a~
etalon is in ~he increas~d eDmplexi$y in the tunlng proce~s. GQnarally wi~ such an ~rrange~en~, b~th the grating a~d ~he etalon ~ill have ~o be moved~ ~h~re ~he et~lon i~ piezo-~unable, as i5 the case wi~h the above mentl~ned Fabry-Perot device, it b~comes readily pos~i~le ~0 tune ths ~talon and ~ove the grating ~imultaneou~ly, hen~e ensurlng a narro~ linewld~h ou~put (de~er~lned by the e~alon tran~mission window) while avoidlng mode h~pping.
~ ~ ~ 31 39~9 The paeka~3 ds~cr1b~d abov~ ~ay ha m~diflad ~or use a~ a laser amplifier package a8 shown in Figur~ 4~ In ~nis in~tance both facet~ o~ ~h~ la~er ~re ~ntl~r~fle~tlon coated and ~he qratin~ i8 anql~d with re~p~ct to ~he optlcal ~th ~o that the re~l~ct~d light d~Q~ not re-enter the laser but i~ directed on to a prl~m 14 ~nd then a PIN
pho~odiode 15~ alterna~ively an in-line ~ er or gra~ing m~y be u~ed ~ the po~tion ~hown in Fi~ur~ 5~ In this latter ~n~ance the ~ilter or gratln~ ~upport is ~odified to provid~ a contitluous optic~ th~
The gr~ting or fllter may be u~d betwe~n spher~c~ ns~
a~ described in our cop~n~n~ appli~a~ion PC~/~B~7/00715 the lens 5 or the len~ ~ and window ~ may bs replaced by the ~irst ~ph~rical lens. ~hen a reflection grating i6 ~5 u~ed the g~a~ing i~ optl~ally in~erpos~d bet~en ~h~
lenses but not phy31cally 80. A la~er amplifler p~ckage with such a gra~lng or filter ~ay b~ u~ o provide tuning for a tunable receiYer.
Claims (15)
1. A device assembly comprising:
a light emitting element, an optical processing element, and means for mounting the optical processing element in a spaced relationship to the light emitting element, the light emitting element being disposed within a hermetically sealed package having a transparent portion for the passage of light to the optical processing element disposed outside the hermetically sealed package, wherein said mounting means comprises a plurality of piezoelectric stacks arranged such that selective elongation and/or contraction of the piezoelectric stacks provides rotational and translational movement of the optical processing element thereby modifying said spaced relationship.
a light emitting element, an optical processing element, and means for mounting the optical processing element in a spaced relationship to the light emitting element, the light emitting element being disposed within a hermetically sealed package having a transparent portion for the passage of light to the optical processing element disposed outside the hermetically sealed package, wherein said mounting means comprises a plurality of piezoelectric stacks arranged such that selective elongation and/or contraction of the piezoelectric stacks provides rotational and translational movement of the optical processing element thereby modifying said spaced relationship.
2. A device assembly according to claim 1 in which the mounting means further comprises a support member extending parallel to the piezoelectric stacks.
3. A device assembly according to claim 2 in which the support member extends partially inwardly between the piezoelectric stacks, the optical processing element being mounted on that portion of the support member which extends between the piezoelectric stacks, whereby the support member enables compensation for thermal expansion in the opposite direction of the support member.
4. A device assembly according to claim 1 further comprising a lens mounted externally of the sealed package in the path of light passing from the light emitting element to the optical processing element via said transparent portion.
5. A device assembly according to claim 4 in which the lens has a focal length of at least 2 mm.
6. A device assembly according to claim 4 in which the lens is mounted in a screw threaded holder.
7. A device assembly according to claim 6 in which the threads of the holder are gold plated.
8. A device assembly according to claim 6 in which the lens holder is welded in position after focussing.
9. An external cavity laser assembly according to claim 4 in which the lens is constructed to compensate for aberrations due to the transparent portion of the package.
10. A device assembly according to any one of claims 1-9 in which the light emitting element is a semiconductor laser and the optical processing element is a grating defining an external cavity for the laser.
11. A device assembly according to any one of claims 1-9 in which the light emitting element is a semiconductor laser amplifier and the optical processing element is a tunable filter.
12. A device assembly according to any one of claims 1-9 in which the assembly external of the hermetic package is substantially symmetrical about the optical axis.
13. A device assembly comprising:
a light emitting element and an optical processing element disposed to intercept light emanating from said light emitting element;
said optical processing element and said light emitting element being spaced apart by plural piezoelectric supports and at least one other support, said supports providing compensating thermal expansion and contraction movements so that thermally induced change in said spacing in a first direction caused by said piezoelectric supports is compensated by thermally induced change in said spacing in an opposite second direction caused by said other support.
whereby the spacing between said optical processing element and said light emitting element is maintained at more constant dimension as a function of device assembly temperature.
a light emitting element and an optical processing element disposed to intercept light emanating from said light emitting element;
said optical processing element and said light emitting element being spaced apart by plural piezoelectric supports and at least one other support, said supports providing compensating thermal expansion and contraction movements so that thermally induced change in said spacing in a first direction caused by said piezoelectric supports is compensated by thermally induced change in said spacing in an opposite second direction caused by said other support.
whereby the spacing between said optical processing element and said light emitting element is maintained at more constant dimension as a function of device assembly temperature.
14. A device assembly comprising:
a semiconductor laser;
a grating defining an external cavity for the laser, the laser being disposed within a hermetically sealed package having a transparent portion for the passage of light to said grating disposed outside the hermetically sealed package, said grating being supported and spaced from said transparent portion by a plurality of at least three independently controllable piezoelectric stacks disposed so that selective elongation and/or contraction of the piezoelectric stacks can provide rotational and translational movement of the grating thereby modifying its spaced relationship to the laser.
a semiconductor laser;
a grating defining an external cavity for the laser, the laser being disposed within a hermetically sealed package having a transparent portion for the passage of light to said grating disposed outside the hermetically sealed package, said grating being supported and spaced from said transparent portion by a plurality of at least three independently controllable piezoelectric stacks disposed so that selective elongation and/or contraction of the piezoelectric stacks can provide rotational and translational movement of the grating thereby modifying its spaced relationship to the laser.
15. A device assembly comprising:
a semiconductor laser;
a tunable filter;
the laser being disposed within a hermetically sealed package having a transparent portion for the passage of light to said tunable filter disposed outside the hermetically sealed package, said tunable filter being supported and spaced from said transparent portion by a plurality of at least three independently controllable piezoelectric stacks disposed so that selective elongation and/or contraction of the piezoelectric stacks can provide rotational and translational movement of the filter thereby modifying its spaced relationship to the laser.
a semiconductor laser;
a tunable filter;
the laser being disposed within a hermetically sealed package having a transparent portion for the passage of light to said tunable filter disposed outside the hermetically sealed package, said tunable filter being supported and spaced from said transparent portion by a plurality of at least three independently controllable piezoelectric stacks disposed so that selective elongation and/or contraction of the piezoelectric stacks can provide rotational and translational movement of the filter thereby modifying its spaced relationship to the laser.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8807385.3 | 1988-03-29 | ||
| GB888807385A GB8807385D0 (en) | 1988-03-29 | 1988-03-29 | Semiconductor device assembly |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1313909C true CA1313909C (en) | 1993-02-23 |
Family
ID=10634261
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000595110A Expired - Fee Related CA1313909C (en) | 1988-03-29 | 1989-03-29 | Semiconducteur device assembly |
Country Status (10)
| Country | Link |
|---|---|
| US (1) | US5058124A (en) |
| EP (1) | EP0335691B1 (en) |
| JP (1) | JP2944692B2 (en) |
| AT (1) | ATE117846T1 (en) |
| AU (1) | AU608975B2 (en) |
| CA (1) | CA1313909C (en) |
| DE (1) | DE68920765T2 (en) |
| ES (1) | ES2067533T3 (en) |
| GB (1) | GB8807385D0 (en) |
| WO (1) | WO1989009503A1 (en) |
Families Citing this family (84)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2664393B1 (en) * | 1990-07-06 | 1992-09-11 | Alsthom Cge Alcatel | TUNABLE OPTICAL CAVITY. |
| US5956355A (en) * | 1991-04-29 | 1999-09-21 | Massachusetts Institute Of Technology | Method and apparatus for performing optical measurements using a rapidly frequency-tuned laser |
| SE468337B (en) * | 1991-05-08 | 1992-12-14 | Radians Innova Ab | SETTING AND ADJUSTING A LASER AND LASER DEVICE WHICH IMPLEMENTS THE SET |
| US5268922A (en) * | 1991-10-31 | 1993-12-07 | International Business Machines Corporation | Laser diode assembly |
| US5197076A (en) * | 1991-11-15 | 1993-03-23 | Davis James G | Temperature stabilizable laser apparatus |
| JP3260795B2 (en) * | 1992-02-14 | 2002-02-25 | キヤノン株式会社 | Injection optical device and automatic adjustment device thereof |
| US5260828A (en) * | 1992-03-27 | 1993-11-09 | Polaroid Corporation | Methods and means for reducing temperature-induced variations in lenses and lens devices |
| US5319668A (en) * | 1992-09-30 | 1994-06-07 | New Focus, Inc. | Tuning system for external cavity diode laser |
| US5513198A (en) * | 1993-07-14 | 1996-04-30 | Corning Incorporated | Packaging of high power semiconductor lasers |
| US5392305A (en) * | 1993-07-14 | 1995-02-21 | Corning Incorporated | Packaging of high power semiconductor lasers |
| US5367140A (en) * | 1993-12-27 | 1994-11-22 | At&T Bell Laboratories | Method for laser welding of optical packages |
| DE19548647C2 (en) | 1995-12-14 | 2003-01-23 | Manfred Gabbert | Tunable, adjustable stable semiconductor laser light source and a method for optically stable, largely continuous tuning of semiconductor lasers |
| US6100975A (en) * | 1996-05-13 | 2000-08-08 | Process Instruments, Inc. | Raman spectroscopy apparatus and method using external cavity laser for continuous chemical analysis of sample streams |
| US6028667A (en) * | 1996-05-13 | 2000-02-22 | Process Instruments, Inc. | Compact and robust spectrograph |
| GB9702126D0 (en) * | 1997-02-03 | 1997-03-26 | Integrated Optical Components | Optical component assemblies |
| US6198580B1 (en) | 1998-08-17 | 2001-03-06 | Newport Corporation | Gimballed optical mount |
| WO2000016453A1 (en) | 1998-09-11 | 2000-03-23 | New Focus, Inc. | Tunable laser |
| JP3713987B2 (en) * | 1998-11-25 | 2005-11-09 | 横河電機株式会社 | External cavity light source |
| US6588949B1 (en) | 1998-12-30 | 2003-07-08 | Honeywell Inc. | Method and apparatus for hermetically sealing photonic devices |
| US6516130B1 (en) | 1998-12-30 | 2003-02-04 | Newport Corporation | Clip that aligns a fiber optic cable with a laser diode within a fiber optic module |
| FR2790115B1 (en) | 1999-02-23 | 2001-05-04 | Micro Controle | METHOD AND DEVICE FOR MOVING A MOBILE ON AN ELASTICALLY MOUNTED BASE |
| US6996506B2 (en) | 1999-02-23 | 2006-02-07 | Newport Corporation | Process and device for displacing a moveable unit on a base |
| US6879619B1 (en) | 1999-07-27 | 2005-04-12 | Intel Corporation | Method and apparatus for filtering an optical beam |
| US6853654B2 (en) | 1999-07-27 | 2005-02-08 | Intel Corporation | Tunable external cavity laser |
| US6511035B1 (en) | 1999-08-03 | 2003-01-28 | Newport Corporation | Active vibration isolation systems with nonlinear compensation to account for actuator saturation |
| US6847661B2 (en) | 1999-09-20 | 2005-01-25 | Iolon, Inc. | Tunable laser with microactuator |
| US6856632B1 (en) | 1999-09-20 | 2005-02-15 | Iolon, Inc. | Widely tunable laser |
| DE60040047D1 (en) * | 1999-10-28 | 2008-10-09 | Fujifilm Corp | Optical wavelength conversion system and wavelength stabilized laser |
| US6792178B1 (en) | 2000-01-12 | 2004-09-14 | Finisar Corporation | Fiber optic header with integrated power monitor |
| US7209498B1 (en) | 2000-05-04 | 2007-04-24 | Intel Corporation | Method and apparatus for tuning a laser |
| US7120176B2 (en) | 2000-07-27 | 2006-10-10 | Intel Corporation | Wavelength reference apparatus and method |
| US6658034B2 (en) * | 2000-12-13 | 2003-12-02 | Picarro, Inc. | Surface-emitting semiconductor laser |
| US6655840B2 (en) | 2001-02-13 | 2003-12-02 | Newport Corporation | Stiff cross roller bearing configuration |
| US6658031B2 (en) | 2001-07-06 | 2003-12-02 | Intel Corporation | Laser apparatus with active thermal tuning of external cavity |
| US6601524B2 (en) | 2001-03-28 | 2003-08-05 | Newport Corporation | Translation table with a spring biased dovetail bearing |
| US6791058B2 (en) | 2001-04-25 | 2004-09-14 | Newport Corporation | Automatic laser weld machine for assembling photonic components |
| US6568666B2 (en) | 2001-06-13 | 2003-05-27 | Newport Corporation | Method for providing high vertical damping to pneumatic isolators during large amplitude disturbances of isolated payload |
| US6717964B2 (en) * | 2001-07-02 | 2004-04-06 | E20 Communications, Inc. | Method and apparatus for wavelength tuning of optically pumped vertical cavity surface emitting lasers |
| US6619611B2 (en) | 2001-07-02 | 2003-09-16 | Newport Corporation | Pneumatic vibration isolator utilizing an elastomeric element for isolation and attenuation of horizontal vibration |
| US6724797B2 (en) | 2001-07-06 | 2004-04-20 | Intel Corporation | External cavity laser with selective thermal control |
| US6822979B2 (en) | 2001-07-06 | 2004-11-23 | Intel Corporation | External cavity laser with continuous tuning of grid generator |
| US6804278B2 (en) | 2001-07-06 | 2004-10-12 | Intel Corporation | Evaluation and adjustment of laser losses according to voltage across gain medium |
| US6901088B2 (en) | 2001-07-06 | 2005-05-31 | Intel Corporation | External cavity laser apparatus with orthogonal tuning of laser wavelength and cavity optical pathlength |
| US7230959B2 (en) | 2002-02-22 | 2007-06-12 | Intel Corporation | Tunable laser with magnetically coupled filter |
| US6966535B2 (en) | 2002-05-07 | 2005-11-22 | Newport Corporation | Snubber for pneumatically isolated platforms |
| US6967976B2 (en) * | 2002-08-29 | 2005-11-22 | Picarro, Inc. | Laser with reflective etalon tuning element |
| US6959023B1 (en) * | 2002-08-29 | 2005-10-25 | Picarro, Inc. | Laser with reflective etalon tuning element |
| US6940879B2 (en) * | 2002-12-06 | 2005-09-06 | New Focus, Inc. | External cavity laser with dispersion compensation for mode-hop-free tuning |
| US20050270856A1 (en) * | 2004-06-03 | 2005-12-08 | Inphase Technologies, Inc. | Multi-level format for information storage |
| US7739577B2 (en) * | 2004-06-03 | 2010-06-15 | Inphase Technologies | Data protection system |
| US8071260B1 (en) | 2004-06-15 | 2011-12-06 | Inphase Technologies, Inc. | Thermoplastic holographic media |
| US20060056465A1 (en) * | 2004-09-10 | 2006-03-16 | Jinchun Xie | Laser with reflective etalon tuning element |
| US8231098B2 (en) | 2004-12-07 | 2012-07-31 | Newport Corporation | Methods and devices for active vibration damping of an optical structure |
| US7704643B2 (en) * | 2005-02-28 | 2010-04-27 | Inphase Technologies, Inc. | Holographic recording medium with control of photopolymerization and dark reactions |
| US7623279B1 (en) | 2005-11-22 | 2009-11-24 | Inphase Technologies, Inc. | Method for holographic data retrieval by quadrature homodyne detection |
| US20060281021A1 (en) * | 2005-05-26 | 2006-12-14 | Inphase Technologies, Inc. | Illuminative treatment of holographic media |
| US7548358B2 (en) * | 2005-05-26 | 2009-06-16 | Inphase Technologies, Inc. | Phase conjugate reconstruction of a hologram |
| US8305700B2 (en) * | 2005-05-26 | 2012-11-06 | Inphase Technologies, Inc. | Holographic drive head and component alignment |
| US7480085B2 (en) * | 2005-05-26 | 2009-01-20 | Inphase Technologies, Inc. | Operational mode performance of a holographic memory system |
| US20060280096A1 (en) * | 2005-05-26 | 2006-12-14 | Inphase Technologies, Inc. | Erasing holographic media |
| US20060279819A1 (en) * | 2005-05-26 | 2006-12-14 | Inphase Technologies, Inc. | Laser mode stabilization using an etalon |
| US7633662B2 (en) | 2005-05-26 | 2009-12-15 | Inphase Technologies, Inc. | Holographic drive head alignments |
| US7675025B2 (en) * | 2005-05-26 | 2010-03-09 | Inphase Technologies, Inc. | Sensing absolute position of an encoded object |
| US7742211B2 (en) * | 2005-05-26 | 2010-06-22 | Inphase Technologies, Inc. | Sensing and correcting angular orientation of holographic media in a holographic memory system by partial reflection, the system including a galvano mirror |
| US20060291022A1 (en) * | 2005-05-26 | 2006-12-28 | Inphase Technologies, Inc. | Optical delay line in holographic drive |
| US7813017B2 (en) * | 2005-10-21 | 2010-10-12 | Inphase Technologies, Inc. | Method and system for increasing holographic data storage capacity using irradiance-tailoring element |
| US7739701B1 (en) | 2005-11-22 | 2010-06-15 | Inphase Technologies, Inc. | Data storage cartridge loading and unloading mechanism, drive door mechanism and data drive |
| US7773276B2 (en) * | 2006-03-07 | 2010-08-10 | Inphase Technologies, Inc. | Method for determining media orientation and required temperature compensation in page-based holographic data storage systems using data page Bragg detuning measurements |
| JP2009529786A (en) * | 2006-03-09 | 2009-08-20 | インフェイズ テクノロジーズ インコーポレイテッド | External cavity laser |
| US20070242589A1 (en) * | 2006-04-13 | 2007-10-18 | Inphase Technologies, Inc. | Stabilizing holographic disk medium against vibrations and/or controlling deflection of disk medium |
| WO2007124459A2 (en) * | 2006-04-20 | 2007-11-01 | Inphase Technologies, Inc. | Index-contrasting-photoactive polymerizable materials, and articles and methods using same |
| US8120832B2 (en) * | 2006-05-23 | 2012-02-21 | Inphase Technologies, Inc. | High speed electromechanical shutter |
| US8079040B2 (en) | 2006-06-06 | 2011-12-13 | Inphase Technologies, Inc. | Loading and unloading mechanism for data storage cartridge and data drive |
| US7495838B2 (en) | 2006-07-19 | 2009-02-24 | Inphase Technologies, Inc. | Collimation lens group adjustment for laser system |
| US20080059144A1 (en) * | 2006-09-01 | 2008-03-06 | Inphase Technologies | Emulation of dissimilar removable medium storage device types assisted by information embedded in the logical format |
| US20090103416A1 (en) * | 2007-10-17 | 2009-04-23 | Inphase Technologies, Inc. | Layout method for multiplexed holograms |
| US9036668B2 (en) | 2008-06-18 | 2015-05-19 | National Institute Of Metrology P.R. China | Grating external-cavity semiconductor laser and quasi-synchronous tuning method thereof |
| EP2451033A4 (en) * | 2009-06-30 | 2013-01-09 | Shandong Fareach Optics Inc | Continuous mode-hop-free grating-tuned external cavity semiconductor laser |
| US8756976B2 (en) | 2011-09-13 | 2014-06-24 | Honeywell International Inc. | Systems and methods for gettering an atomic sensor |
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| US9746608B1 (en) * | 2014-12-11 | 2017-08-29 | Partow Technologies, Llc. | Integrated optical assembly apparatus and integrated fabrication method for coupling optical energy |
| CN112310807A (en) * | 2019-08-02 | 2021-02-02 | 苏州旭创科技有限公司 | External cavity tunable laser and optical module |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2612012C3 (en) * | 1976-03-20 | 1979-02-08 | Max-Planck-Gesellschaft Zur Foerderung Der Wissenschaften E.V., 3400 Goettingen | Electronic control and regulation device for the distance or the parallelism of two reflectors of an optical device |
| JPS5621391A (en) * | 1979-07-28 | 1981-02-27 | Ritsuo Hasumi | External resonator-equipped semiconductor laser element |
| US4438514A (en) * | 1982-02-16 | 1984-03-20 | United Technologies Corporation | Sure-start waveguide laser |
| JPS59193080A (en) * | 1983-04-15 | 1984-11-01 | Hitachi Ltd | Light emitting semiconductor device |
| US4830486A (en) * | 1984-03-16 | 1989-05-16 | Goodwin Frank E | Frequency modulated lasar radar |
| DE3444823C2 (en) * | 1984-12-08 | 1986-10-02 | Messerschmitt-Bölkow-Blohm GmbH, 8012 Ottobrunn | Detachable connection between an optical fiber and a laser device |
| JPS61145876A (en) * | 1984-12-20 | 1986-07-03 | Mitsubishi Electric Corp | Package for light emitting device |
| US4758764A (en) * | 1985-06-05 | 1988-07-19 | Matsushita Electric Industrial Co., Ltd. | Light-emitting device for automatic focus adjustment apparatus |
| DE3610540A1 (en) * | 1986-03-27 | 1987-10-01 | Kernforschungsanlage Juelich | MOTION DEVICE FOR MICROMOVING OBJECTS |
| US4918702A (en) * | 1987-12-02 | 1990-04-17 | Canon Kabushiki Kaisha | Laser unit |
| US4919532A (en) * | 1988-08-15 | 1990-04-24 | Mocker Hans W | High accuracy semiconductor laser doppler velocimeter |
| US4907237A (en) * | 1988-10-18 | 1990-03-06 | The United States Of America As Represented By The Secretary Of Commerce | Optical feedback locking of semiconductor lasers |
-
1988
- 1988-03-29 GB GB888807385A patent/GB8807385D0/en active Pending
-
1989
- 1989-03-29 WO PCT/GB1989/000324 patent/WO1989009503A1/en unknown
- 1989-03-29 EP EP89303110A patent/EP0335691B1/en not_active Expired - Lifetime
- 1989-03-29 AT AT89303110T patent/ATE117846T1/en not_active IP Right Cessation
- 1989-03-29 ES ES89303110T patent/ES2067533T3/en not_active Expired - Lifetime
- 1989-03-29 DE DE68920765T patent/DE68920765T2/en not_active Expired - Lifetime
- 1989-03-29 JP JP1504523A patent/JP2944692B2/en not_active Expired - Lifetime
- 1989-03-29 CA CA000595110A patent/CA1313909C/en not_active Expired - Fee Related
- 1989-03-29 AU AU34252/89A patent/AU608975B2/en not_active Ceased
- 1989-03-29 US US07/424,284 patent/US5058124A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| ES2067533T3 (en) | 1995-04-01 |
| GB8807385D0 (en) | 1988-05-05 |
| DE68920765T2 (en) | 1995-05-18 |
| WO1989009503A1 (en) | 1989-10-05 |
| ATE117846T1 (en) | 1995-02-15 |
| DE68920765D1 (en) | 1995-03-09 |
| EP0335691A1 (en) | 1989-10-04 |
| AU3425289A (en) | 1989-10-16 |
| US5058124A (en) | 1991-10-15 |
| JPH03500353A (en) | 1991-01-24 |
| EP0335691B1 (en) | 1995-01-25 |
| AU608975B2 (en) | 1991-04-18 |
| JP2944692B2 (en) | 1999-09-06 |
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