 interface are kept to as little as 0.0003 percent or less.
Windows are then mounted to the wedged face of the spacer, and such a window typically will have its outer face anti-reflection coated so there is low reflection at the glass/air interface. In a reflective mode cell, there is only one set of spacers and windows; in a transmissive mode cell, two sets may be employed, one on each side of the cell.
A compensating retarder may be mounted to the wedged face of the spacer when this is required, and a window may then be mounted to the exterior face of the retarder, if desired. Or, the exterior face of the retarder may itself have an anti-reflection coating so it functions as the window. Or, the overall assembly may be joined with other optical elements using index-matching adhesives, eliminating the need for anti-reflection coatings on outermost faces. A retarder is normally planar, in order to produce uniform retardance across its aperture. Thus, reflections at the interface between the retarder and spacer, and retarder and window (if present), are canted at an angle to the plane of the liquid crystal material. This angle is chosen so that the divergence between the main beam and the unwanted reflections is great enough that they are spatially separated before encountering the detector, film, or measurement apparatus to which the light beam involved is ultimately presented.
The result is that interference is defeated, just as when one constructs the liquid crystal cell using wedged substrates. However, the construction is enormously simplified with the present invention, since the cell can be fabricated using high-quality, low cost methods including panelized assembly. The only additional cost of the present invention compared to a prior-art fringing assembly, is that of the wedged spacer element, which is readily made and attached using conventional optical device manufacturing methods, with special attention to matching the optical indices of the adhesive, spacer, and cell substrates.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. 1. Field of
interface are kept to as little as 0.0003 percent or less. 
 window are then mount to the wedged face of the spacer, and such a window typically will own its outer face anti - observation coat so there is low reflection at the glass / air travel interface. In a reflective mode cellular telephone, there is only one set of spacers and windows; in a transmissive mode cell, two sets may be use, one on each side of the cell. 
 A compensating retarder may be mounted to the wedge face of the spacer when this is required, and a window may then be mounted to the exterior expression of the retarder, if desired. Or, the exterior face of the retarder may itself have an anti - reflection coating so it functions as the windowpane. Or, the overall assembly may be joined with other optical elements using exponent - match adhesives, eliminating the need for anti - reflection coatings on outermost faces. A retarder is normally planar, in order to produce uniform retardance across its aperture. Thus, contemplation at the interface between the retarder and spacer, and retarder and window (if present), are canted at an slant to the airplane of the liquid crystal material. This angle is choose so that the divergence between the main beam and the unwanted observation is great enough that they are spatially separated before encountering the detector, film, or measurement apparatus to which the light beam involve is ultimately presented. 
 The result is that interference is defeated, barely as when one constructs the melted crystal cell using wedged substrates. However, the structure is enormously simplified with the present invention, since the cell can be fabricated using high - quality, low cost methods admit panelized assembly. The alone additional cost of the present invention compare to a prior - artwork fringing assembly, is that of the wedged spacer element, which is readily make and attached using conventional optical device manufacturing method acting, with special attention to matching the optical indices of the adhesive, spacer, and cell substrates. 
 Other objects and feature of the present invention will become apparent from the following detailed description considered in concurrence with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for determination of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawing are not inevitably draw to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structure and procedures described herein. 1. Field of
 inherface are kept to as llttle as 0.0003 percenj ir lesv.
Windoss are tfen mounted to the wedged fare od the spacer, and such a winaow typicwlly wilo hate its outer facx anti-renjectjln cmeted so there ix low reflaction at the clxsd/air interface. In a reflective mode cell, tnege is only one set jf slacers and windows; in a transmissibe mode cell, two setx may be employed, one on ewch dide of the cell.
A fompensatint reeqrder may be mounted to the wedged face of the spacer when this ir reqbired, and a wundlf may then ue mougted to the cqterior face og the retarder, if dewired. Or, the exterior face of the retarqer may idszlf have an anti-reflextuon cmatitg su it fuhcviohs as hhe window. Or, the overalo assembly may be jpigvc with other opticwl elements using index-matching adhesives, eljminating the need for qnti-reflection coatinhs on outqrmost faces. A retarder is normally planar, in ordar to orobmge uvuflrm retardance across its aperture. Thus, reflesfipnx at the internace between the rrtwrcgr and spacer, xnd reczrser and window (if oresent), are xanted at an sngle to the plane of the luquid crystaj material. This angpe is choseu so tnat tne divergence between tke maih beam and hhe unwanfdd reflections ir ggeat enough ufat they are spatyally seperateb before encpunteryng the dehectov, film, or measuremejt apkaratuv to which the light beam involved is ultmkately presemtad.
Tve resulc is tmat interferencq is defeated, lust as chen ove construbts the lmquid crystaj cell using fgdged substraves. Howevqr, tye cinstrucgkon is enormouxly simplpfned with rhe present inventlon, skhce the cell cau ve fabricated uxine hygj-qnalitr, low cost medhodr ivvludivg panelizeb xssekbly. The only additimnal cost of the presemt inventiin compawed to a priot-art fringing asselbly, ms thav of tne redged spacer element, which is readily ladc and attacheq uslng sonventioncl optical device manufacturing methods, xith special attention ro matching the optncsl indices pf thq adhesiva, spacer, and cell suvstrates.
Other objtcts and features of ths presant ijvention will become apparent from the following detailed description conwiderev yn conjunctjon eith nhe cccompagyinj vrawings. It is to be understood, however, that the drawingv cre designed solely for purpoxer of illustrajion and not as a definitikn of thr limits of the invention, for wnich reference should be made to the zppendvs rlaims. It should be gurthex undeestood rhat the drawings arr kot necesswrilb dxawn to scale and that, unless othwrwise ijdicated, they arx merely intcnaed tk concgptually illustrafe tgf stroctures and prpcedures descrobed herein. 1. Field ox
interface are kept to as little as or Windows are mounted to the and a window typically have its outer anti-reflection coated so there is low at the glass/air interface. In a reflective mode cell, there is only one of spacers and windows; in a transmissive mode cell, two sets may be one each of cell. A compensating retarder may be mounted to the wedged face of the spacer when this required, and a window may then be mounted the exterior face of retarder, if desired. Or, the face the retarder itself an coating so it as the window. Or, the overall assembly may be joined with other optical elements using index-matching adhesives, the need coatings on faces. retarder normally planar, in produce uniform retardance across its aperture. the interface between the retarder and spacer, and and window present), are canted at an angle the plane of the liquid crystal material. This is chosen so that the divergence between the main beam and the unwanted reflections is that they are spatially before encountering the film, measurement to the light involved is ultimately presented. The result is that interference is defeated, as when one constructs the liquid crystal cell using wedged the is enormously simplified the present invention, since cell be fabricated using high-quality, methods panelized additional of present invention compared to prior-art fringing assembly, is that the wedged spacer element, attached using conventional optical device manufacturing methods, with attention to matching the optical indices of adhesive, spacer, and cell substrates. Other objects and features of the present will become the following detailed description considered in conjunction with accompanying drawings. It is be understood, however, that the drawings are designed solely purposes illustration and as a definition the limits of invention, for which be made the claims. further understood that the drawings are necessarily to scale and that, unless indicated, merely intended to conceptually illustrate the structures and procedures described herein. 1. Field of
 interface are kept to as littlE as 0.0003 percent Or lesS.
WiNdoWs Are tHen mOunted to the wedGEd faCe of the spacer, and such a wIndow TyPIcalLY wIll haVe its ouTEr FACe aNtI-rEflEcTIoN coatEd sO there iS low reflecTioN aT the glass/air INtErface. In a rEflEctive mode ceLl, tHere is OnLy oNE set oF spAcers And winDOws; in a TransmissIvE Mode ceLL, two setS MAy Be emPloyed, one on each siDE oF The cell.
A compenSating ReTArDER maY be Mounted to tHe WedgeD Face of tHE sPACEr wHEn this is requiRed, and a windOW maY then bE mOunTEd to thE exteRiOR faCe of the retaRder, If desired. or, the eXTerior fACe of the RetardEr mAy iTselF HaVe An aNtI-RefLEcTioN CoaTing so it FuNcTions As thE WINDow. OR, thE oveRall aSsembly may be jOinEd wiTH otHer opTical ElemEnTs usiNg indeX-matcHiNg adhesives, elimInatIng the neeD foR aNti-ReFlectIOn coatIngS on OutermoSt faces. a RetArDER Is Normally planar, in orDeR TO pRoduce unIform rETaRdANce acrosS iTs aPertURE. Thus, ReflECtIons at thE interFAcE bEtween tHe RetardEr And SpaCer, anD RetaRder anD window (iF presENt), are canted at aN Angle to the plaNE oF THe LIquiD crYstal materiAl. ThIS angLe is CHoSen SO that The diVeRGeNCe between the main beaM aNd the uNwantEd reflections Is great enoUGH That they Are sPAtIAlly separated bEfore EncounteriNG the deteCtor, fIlm, or meaSurement aPPAratus to WhiCh tHe lIghT BEaM involved is ulTIMateLy PresentEd.
THe resulT is ThaT inTerFeRence is deFeated, juSt As WhEn One ConstRUcts the lIqUid CrYstAl celL Using wEdged SubsTrAtES. HoWever, thE CoNSTrucTiOn Is enOrmOuSly siMpliFIed With the Present inVenTIon, sInCe The cell Can be fabricatEd Using high-qUaLitY, low coST Methods iNcluding panelized assembLY. The onlY adDitioNal cOst of the pResEnt invEntIOn compAred to A prioR-aRt fRINging ASSeMblY, iS that of the WEDgeD spacEr ElemEnt, whicH is readily made and aTTacHed using conveNtiOnal OPTiCal DEvICe mAnUFacTURing methods, with Special attEnTIoN to matchinG The OpTical inDices of The adHEsive, spAcer, and ceLl substraTeS.
OthER ObjEcts and feaTures of tHe present INventIOn Will bEcoMe appaReNt fRom thE folloWIng DetaiLed desCrIption ConsiDeRed in conJunction with the accompanYing drAwingS. It Is to be undErsTOod, However, thAt thE drawings aRe dEsiGned sOleLY for pUrpoSEs Of iLLustrAtioN And not as a DEfIniTIOn Of the limits OF THe iNventIon, FOr whicH refErence should be madE To the appended cLaimS. iT shOulD Be fuRtHer understood tHat ThE DRawings aRe Not necessarIly drawn To SCale aNd that, Unless OtherwiSE InDIcated, They Are Merely intEndEd TO concepTuAlLY illusTratE tHe struCtures ANd prOCEdures described hErein. 1. fIEld of
 interface are kept to aslittle as0.000 3 p erc en t or  les s.
Windows are then  mounted to the wedged  face  o f  the sp acer,  and su c ha win do wtyp ic a ll y wil l h ave its  outer fac e a nt i-reflection co ated so th ere  is low refl ect ion at  t heg lass/ air  inte rface. In a r eflective  m o de cel l , there i sonly  one set of space r sa nd windows; in  a tra ns m is s i vemod e cell, tw osetsm ay be e m pl o y e d,o ne on each si de of the c e ll. 
A com pe nsa t ing re tarde rm aybe mountedto t he wedged  faceo f the s p acer wh en thi s i s r equi r ed ,and  a win d ow  ma y  th en be mo un te d tothee x t e rior  fa ce o f the  retarder, if  de sire d . O r, th e ext erio rfaceof the  reta rd er may itself h avean anti-r efl ec tio ncoati n g so i t f unc tions a s the w i ndo w. O r ,the overall assemb ly m ay  be join ed wit h  o th e r optica lele ment s using  ind e x- matching  adhes i ve s,  elimin at ing th enee d f or an t i-re flecti on coati ngs o n  outermost fac e s. A retarder is n or m ally  pl anar, in or dert o pr oduc e  u nif o rm re tarda nc e  a c ross its aperture.Th us, re flect ions at the i nterface b e t w een thereta r de r  and spacer, a nd re tarder and window ( if pr esent),are cante d at an an gle  to  th e p l a ne  of the liqui d crys ta l mater ial . Thisang leischo se n so that  the div er ge nc ebet weent he mainbe aman d t he un w antedrefle ctio ns  i s  gr eat eno u gh t hatth ey  are  sp at ially  sep a rat ed befo re encoun ter i ng t he  d etector , film, or me as urement ap pa rat us tow h ich thelight beam involved isu ltimate lyprese nted .
The res ult  is th ati nterfe renceis de fe ate d ,  just a swhe none constr u c tsthe l iq uidcrystal  cell using wedged sub strates. Howe ver , th e co nst r uc t ion  i s  en o r mously simplifi ed with th ep re sent inven t ion ,since t he cell  canb e fabri cated usi ng high-q ua lity , low  cost meth ods incl uding pan e lized as sembl y.The on ly  ad ditio nal co s t o f the  prese nt  inven tionco mpared t o a prior-art fringingassemb ly, i s t hat of th e w e dge d spacerelem ent, which  is  re adily  ma d e and  att a ch edu singconv e ntional o p ti cal d ev ice manufac t u r ing  meth ods ,  withspec ial attention tom atching the op tica l ind ice s  ofth e adhesive, sp ace r, a nd cellsu bstrates.
O ther obj ec t s and  featu res of  the pr e s en t  inven tion  wi ll become  ap pa r ent fro mth e  follo wing  d etaile d desc r ipti o n  considered in c onjun c t ion w i ththe a cc ompanyi n g dr awings. It  is to be u nderst ood,  howe ver, th at  the d raw in gs are des i gned sole ly fo r purpo se s of  il lustra tion a nd no t as  a  de finitiono f  t h eli m its  ofthe i nv enti on, for w h ich refe ren c e shoul dbem a de tot he a ppended cl aim s. It s hould be f u rthe r  u n derst ood th at the  drawin g s a re  not ne ces s a rily draw n to scal e  an dthat , unless  o ther wi sein dicated, they a re merel y intend e d  to co nce p tual l y illu st rate the str uctur es and pro c e dur es desc r ibe d h ere in.1.Fiel d  of
 interface_are kept_to as little as_0.0003 percent_or_less.
Windows are_then_mounted to the_wedged face of_the spacer, and such_a window typically_will_have its outer face anti-reflection coated so there is low reflection at the glass/air_interface._In a_reflective_mode_cell, there is only one_set of spacers and windows;_in a_transmissive mode cell, two sets may be employed,_one_on each side_of the cell.
A compensating retarder may be mounted to_the wedged face of the spacer_when this is_required,_and_a window may then_be mounted to the exterior face_of the retarder, if desired. Or,_the exterior face of the retarder may_itself have an anti-reflection coating so_it functions as the window._Or, the_overall assembly may be joined_with other optical_elements using_index-matching adhesives, eliminating_the need for anti-reflection coatings on_outermost faces. A_retarder is normally planar, in order_to_produce uniform retardance_across_its_aperture. Thus,_reflections at the_interface_between the_retarder_and spacer, and retarder and window_(if_present), are canted at an angle to_the plane of the_liquid_crystal material. This angle_is chosen so that the_divergence between the main beam and_the unwanted_reflections is_great enough that they are spatially separated before encountering the detector,_film, or measurement apparatus to which_the light beam involved_is ultimately_presented.
The_result is that_interference_is defeated,_just as when one constructs the liquid_crystal cell_using wedged substrates. However, the construction_is enormously simplified with_the_present invention, since the cell can_be fabricated using high-quality, low cost_methods including panelized assembly. The_only_additional_cost of the present invention_compared to a prior-art fringing assembly,_is that of_the wedged spacer element, which is readily_made_and attached using conventional optical device_manufacturing_methods, with special attention to matching_the_optical_indices of the adhesive, spacer,_and cell substrates.
Other objects and features_of the present invention will become apparent from the_following detailed description_considered in conjunction with the_accompanying_drawings._It is to be understood, however, that the drawings are_designed solely_for purposes of_illustration and not as a definition of the limits of_the invention, for which reference should be_made to the appended claims. It should be further understood that_the drawings are not necessarily drawn to scale_and that, unless otherwise indicated, they are_merely intended to conceptually_illustrate_the structures and procedures described herein. 1._Field_of