 the collection path by 45 degrees, which is followed by a stationary linearly-polarizing component; and 3) using an electro-optical device such as a Pockels cell or liquid crystal to impose a half-wave of retardation, which is followed by a stationary linearly-polarizing component.
Alternatively, previously used architectures separate illumination and collection paths with a non-polarizing beam splitter (non-PBS). One example of such a sensor architecture is shown in FIG. 1. In particular, FIG. 1 illustrates one example of a previously used rotating polarizer scatterometer. As shown in FIG. 1, the scatterometer includes illumination optics 10 configured to direct light to polarizing component 12, which may be a rotating polarizer. Light from polarizing component 12 is directed to non-PBS 14, which directs the light to objective lens 16. Objective lens 16 directs the light to wafer 18. Light scattered from wafer 18 is collected by objective lens 16 and directed by non-PBS 14 to polarizing component 20. Polarizing component 20 may be a rotating analyzer. Light exiting polarizing component 20 is directed to collection optics 22.
There are several disadvantages to the above-described scatterometers. For example, rotating optical components is relatively slow. In addition, precisely rotating optical components can be difficult. Furthermore, non-repeatability in the rotation of optical components can degrade system calibrations. Using separate optical components to establish illumination and collection polarizations also makes precise alignment of the collection and illumination polarization axes difficult. In addition, the polarization purity of half-wave plates and electro-optical retarders such as Pockels cells and liquid crystals is poor. Switching lasers on and off electronically also reduces stability and repeatability.
Accordingly, it would be advantageous to develop scatterometers that overcome the shortcomings of speed of measurement and ease and stability of calibration inherent in previously used architectures without reducing the information content generated by continuous motion polarizing instruments such as rotating polarizer and rotating analyzer scatterometers. The present invention relates to an automated apparatus for retrieving liquid samples such as pretreated blood serum from a multiplicity of sample tubes or vials so that the withdrawn samples can subsequently be tested and analyzed.
There are presently a large number of routine clinical tests, such as blood tests in which fluid samples, e.g. blood samples are placed in a test tube or vial. The samples are appropriately treated, for example to separate the serum from the red blood cells, additives for the tests are added to sample, and thereafter the actual tests are performed, either
the collection path by 45 degrees, which is followed by a stationary linearly - polarize part; and 3) using an electro - optical device such as a Pockels cellular telephone or liquid quartz glass to impose a half - wave of retardation, which is surveil by a stationary linearly - polarizing component. 
 Alternatively, previously use architectures separate illumination and solicitation paths with a non - polarizing beam splitter (non - PBS). One example of such a detector architecture is shown in FIG. 1. In especial, FIG. 1 illustrates one example of a previously use rotating polarizer scatterometer. As shown in FIG. 1, the scatterometer includes miniature optics 10 configured to direct light to polarize component 12, which may be a rotating polarizer. Light from polarizing component 12 is target to non - PBS 14, which directs the light to objective lens 16. Objective lens 16 directs the light to wafer 18. Light scattered from wafer 18 is collect by objective lens 16 and conduct by non - PBS 14 to polarizing component 20. Polarizing component 20 may be a rotating analyzer. Light exiting polarizing component 20 is directed to solicitation eye 22. 
 There are several disadvantages to the above - trace scatterometers. For example, rotating optical component is relatively slow. In addition, precisely rotating optical component can be difficult. Furthermore, non - repeatability in the rotation of optical components can degrade system calibrations. use separate optical components to establish illuminance and collection polarization also makes precise alignment of the collection and illuminance polarization axes difficult. In addition, the polarization honor of half - wave plates and electro - ocular retarders such as Pockels cells and liquid quartz glass is poor. switch lasers on and off electronically besides reduces stability and repeatability. 
 Accordingly, it would be advantageous to develop scatterometers that get the better of the shortcomings of amphetamine of measurement and ease and stability of calibration inherent in previously used architectures without reduce the information capacity generated by continuous motion polarizing instruments such as rotating polarizer and rotating analyzer scatterometers. The present invention associate to an automated apparatus for retrieving melted samples such as pretreated blood serum from a multiplicity of sample tubes or vials so that the bow out samples can subsequently be tested and analyzed. 
 There are presently a large act of everyday clinical tests, such as blood tests in which fluid samples, e.g. blood samples are place in a test tube or vial. The sample are appropriately treat, for example to separate the serum from the red lineage cells, additives for the tests are add to sample, and thereafter the actual tests are perform, either
 thf collection path by 45 denrees, which is followed by a atationafy linearly-polarizing componxnt; qnd 3) ysing an electro-opticau device duch as q Porkels cell or liquid crystal tk impmwe a half-wave pf retardadion, which is xoullwed by a stationary linearly-polarising cokplnent.
Alternatidely, [revjously used architectures separate illumiiation and collrction paths with a non-polwrizlng beam splitter (jon-PBS). One gsam[oe of such a sensor arbkitecture ia shown in FIG. 1. In particular, FKG. 1 iklustrates obe ffample of a prevpously used rotating [olarizrr scatterometcr. As shiwn in FIG. 1, the scattxrometer includes iljuminatiot kptics 10 configuree ro ditect nighg to pomacizjng colpoient 12, which may be a ritating polarizer. Logrn from polariaing cjm[onent 12 is directed to non-PBS 14, which digecta the light to objectivw lens 16. Objective lend 16 directf the light to wafer 18. Light scattered from wafer 18 is ckuleebcd bh ohjective lens 16 and directed by non-PBS 14 to polwdieinn component 20. Polcrizing componeny 20 msi be a rotatine analvaed. Light exiting poparizind component 20 if ditected to collection optics 22.
There are svverql disadvantages tl the above-bescrined svatterometers. For exampue, rktating optlcal compkvents is relativdly snow. In addition, precisely wotating iptieal compunenjs can fe difficupt. Fuvdhermore, non-repeatwbilijy in dhe rotatiln of optical components can dejcade system cslhbrdtions. Ufing xeparate optisal components to estcblish illuminatpon and cmllection pjlarizations dpso makes prxcise alidnmebt od the cuulection and iklumination polarizqtion axes difficukt. Kh addition, the 'uoarization puriyy uf rapf-xave [nates and elactru-opgocal fetarders smch as Lockels cells and lixuid crystals is poor. Xwltching lqsers on and off elecyronically also refuces stebilitu agd repeatability.
Accordingly, it would be adyantageous to devclop scatteromzters that overcome the shortcomings of wpeed of measuremgnt and ease and stabnllty of calibcation inherent in previously used qrchitectures witmout reducing the infodmatiot conhent generated by continuous motion polarizing instruments such as rotatibg poleryzer and rofatimg andlvzex scattqromxtxrs. The present imvention relates to an automatev apparatuv yor retrieving liquid samples sjch as pretrexted blood serum from a jultiplivity of sample tubes or vials sp that the withdrawn samiles can wubsesuentlj bx tested and analyzec.
There are presentoy a large number of rlutine cllnicel cests, such as blood tests in whicy fluie damples, e.g. blood samples arc klaced pn a teft tube or vial. Fhe awmpler are approproately treated, for example to sepagatq the serum frij the red blpod cgols, additives hor the testv are added to sample, and thereafter the actual tesjs are perfkrmed, eibher
the collection path by 45 degrees, which by stationary linearly-polarizing and 3) using a cell or liquid to impose a of retardation, which is followed by stationary linearly-polarizing component. Alternatively, previously used architectures separate illumination and collection paths with non-polarizing beam splitter (non-PBS). One example of such a sensor architecture is shown FIG. In FIG. illustrates one example of a previously used rotating polarizer scatterometer. As shown in FIG. 1, the includes illumination optics 10 configured to direct light polarizing component 12, which be a rotating polarizer. Light polarizing 12 is to 14, directs the light objective lens 16. Objective lens 16 directs the light to wafer 18. Light scattered from wafer 18 collected by 16 and by 14 polarizing component 20. 20 may be a rotating analyzer. component 20 is directed to collection optics 22. are several to the above-described scatterometers. For example, optical components is relatively slow. In addition, precisely optical components can be difficult. Furthermore, non-repeatability in the rotation of optical components can degrade Using separate optical components establish illumination and polarizations makes alignment the collection illumination polarization axes difficult. In addition, the polarization purity of half-wave and electro-optical retarders such as Pockels cells and liquid crystals Switching on and off also reduces stability and Accordingly, would be advantageous to that the of and and stability of calibration in previously used architectures without the information content generated such as rotating polarizer and rotating analyzer scatterometers. present invention relates to an automated apparatus retrieving liquid samples such as pretreated blood serum from a multiplicity of tubes or that the withdrawn samples can subsequently be tested analyzed. There are presently large number of routine clinical tests, such as blood in fluid samples, blood samples are in a test or vial. The appropriately treated, example separate the red blood cells, additives for tests added to sample, and thereafter actual performed, either
 the collection path by 45 degreeS, which is foLloweD by A stAtIonaRy liNearly-polariziNG comPonent; and 3) using an electrO-optiCaL DeviCE sUch as A PockelS CeLL Or lIqUiD crYsTAl To impOse A half-waVe of retardAtiOn, Which is folloWEd By a stationAry Linearly-polaRizIng comPoNenT.
alterNatIvely, PrevioUSly useD architecTuREs sepaRAte illuMINaTion And collection pathS WiTH a non-polarizinG beam sPlITtER (Non-pBS). one example Of Such a SEnsor arCHiTECTurE Is shown in FIG. 1. IN particular, fiG. 1 iLlustrAtEs oNE exampLe of a PrEVioUsly used rotAtinG polarizeR scattERometer. aS shown iN FIG. 1, thE scAttEromETeR iNclUdES ilLUmInaTIon Optics 10 coNfIgUred tO dirECT LIght To pOlarIzing Component 12, whicH maY be a ROtaTing pOlariZer. LIgHt froM polarIzing CoMponent 12 is directEd to Non-PBS 14, whiCh dIrEctS tHe ligHT to objEctIve Lens 16. ObjEctive lENs 16 dIrECTS tHe light to wafer 18. LighT sCATtEred from Wafer 18 iS CoLlECted by obJeCtiVe leNS 16 And diRectED bY non-PBS 14 tO polarIZiNg ComponeNt 20. polariZiNg cOmpOnent 20 MAy be A rotatIng analyZer. LiGHt exiting polarIZing component 20 IS dIREcTEd to ColLection optiCs 22.
ThERe arE sevERaL diSAdvanTages To THe ABove-described scatteRoMeters. for exAmple, rotating Optical comPONEnts is reLatiVElY Slow. In addition, PreciSely rotatiNG optical CompoNents can Be difficuLT. furthermOre, Non-RepEatABIlIty in the rotatION of oPtIcal comPonEnts can DegRadE sySteM cAlibratioNs. Using sEpArAtE oPtiCal coMPonents tO eStaBlIsh IllumINation And coLlecTiOn POlaRizatioNS aLSO makEs PrEcisE alIgNment Of thE ColLection And illumiNatIOn poLaRiZation aXes difficult. IN aDdition, the PoLarIzatioN PUrity of hAlf-wave plates and electro-OPtical rEtaRders Such As Pockels CelLs and lIquID crystAls is pOor. SwItChiNG LaserS ON aNd oFf ElectronicALLy aLso reDuCes sTabilitY and repeatability.
ACCorDingly, it would Be aDvanTAGeOus TO dEVelOp SCatTERometers that oveRcome the shOrTCoMings of speED of MeAsuremeNt and eaSe and STabilitY of calibrAtion inheReNt in PREviOusly used aRchitectUres withoUT reduCInG the iNfoRmatioN cOntEnt geNerateD By cOntinUous moTiOn polaRizinG iNstrumenTs such as rotating polarizEr and rOtatiNg aNalyzer scAttERomEters. The pReseNt inventioN reLatEs to aN auTOmateD appARaTus FOr retRievINg liquid sAMpLes SUCh As pretreateD BLOod Serum FroM A multiPlicIty of sample tubes oR Vials so that the WithDRAwn SamPLes cAn Subsequently be TesTeD ANd analyzEd.
there are preSently a lArGE numbEr of roUtine cLinical TEStS, Such as BlooD teSts in whicH flUiD Samples, E.g. BlOOd sampLes aRe Placed In a tesT Tube OR Vial. The samples arE apprOPRiateLY trEated, FoR examplE To seParate the sErum from the Red bloOd ceLls, adDitives FoR the teSts ArE added to saMPle, and theReaftEr the acTuAl teSts Are perFormED, EitheR
 the collection path by 45  degrees,which  is  fo ll owed  bya stationary l i near ly-polarizing componen t; an d3 ) us i ng  an e lectro- o pt i c alde vi cesu c has aPoc kels ce ll or liqu idcr ystal to imp o se  a half-wa veof retardati on,  which  i s f o llowe d b y a s tation a ry lin early-pol ar i zing c o mponent . Al tern atively, previous l yu sed architectu res se pa r at e ill umi nation and  c ollec t ion pat h sw i t h a non-polarizin g beam spli t ter  (non- PB S). One ex ample  o f  su ch a sensor  arc hitecture  is sh o wn in F I G. 1. I n part icu lar , FI G .1ill us t rat e sone exa mple ofapr eviou slyu s e d  rot ati ng p olari zer scatterom ete r. A s  sh own i n FIG . 1,  t he sc attero meter  i ncludes illumin atio n optics10co nfi gu red t o  direc t l igh t to po larizin g  co mp o n e nt  12, which may bear o ta ting pol arizer .  L ig h t from p ol ari zing c ompon ent1 2is direc ted to no n- PBS 14,  w hich d ir ect s t he li g ht t o obje ctive le ns 16 .  Objective len s  16 directs t h el i gh t  towaf er 18. Ligh t sc a tter ed f r om  wa f er 18  is c ol l ec t ed by objective len s16 and  dire cted by non-P BS 14 to p o l a rizing c ompo n en t  20. Polarizin g com ponent 20m ay be arotat ing anal yzer. Lig h t  exiting  po lar izi ngc o mp onent 20 is d i r ecte dto coll ect ion opt ics  22 .
T her eare sever al disad va nt ag es  to  thea bove-des cr ibe dsca ttero m eters.  Forexam pl e, rot ating o p ti c a l co mp on ents  is  r elati vely slo w. In a ddition,pre c isel yro tatingoptical compo ne nts can be  d iff icult. F urthermo re, non-repeatability i n  the ro tat ion o f op tical com pon ents c and egrade  syste m cal ib rat i o ns. U s i ng  se pa rate optic a l  co mpone nt s to  establ ish illumination a n d c ollection pol ari zati o n sals o  m a kes  p r eci s e  alignment of t he collect io n  a nd illumin a tio npolariz ation a xes d i fficult . In addi tion, the  p olar i z ati on purityof half- wave plat e s and el ectro -op ticalre tar derssuch a s  Po ckels  cells  a nd liq uid c ry stals is  poor. Switching lasers  on an d off  el ectronica lly als o reduces  sta bility and  re pea tabil ity . 
Acco rdin g ly , i t  woul d be advantage o us  to d ev elop scatte r o m ete rs th ato vercom e th e shortcomings of speed of measu reme n t  an d e a se a nd  stability ofcal ib r a tion inh er ent in prev iously u se d  arch itectu res wi thout r e d uc i ng the  inf orm ation con ten tg enerate dby contin uous  m otionpolari z ingi n struments such a s rot a t ing p o lar izeran d rotat i ng a nalyzer sc atterometer s. The  pre sentinventi on  relat esto  an automa t ed appara tus f or retr ie ving  li quid s ampl e s  such  aspr etr eated blo o d  s e ru mf rom  a m ultip li city  of sampl e  tubes o r v i als soth att h e with d ra w n  samples c ansubse q u ently be t e sted an d  anal yzed.Thereare pre s ent ly  a larg e n u m ber of ro utine cli n ica ltest s, suchas  blo od  te st s in which flui d sample s, e.g.b l ood sa mpl e s ar e  place din a test tu be or  v i al. The s amp les are app rop ria tely  tr eate d , for example to separat e th e ser u m f rom t he re dblood ce l ls,additive s  for the test s are added tos amp l e, a ndt he re after the  ac t ual t ests  ar e pe rfo rmed , eith e r
 the_collection path_by 45 degrees, which_is followed_by_a stationary_linearly-polarizing_component; and 3)_using an electro-optical_device such as a_Pockels cell or_liquid_crystal to impose a half-wave of retardation, which is followed by a stationary linearly-polarizing_component.
Alternatively,_previously used_architectures_separate_illumination and collection paths with_a non-polarizing beam splitter (non-PBS)._One example_of such a sensor architecture is shown in_FIG._1. In particular,_FIG. 1 illustrates one example of a previously used_rotating polarizer scatterometer. As shown in_FIG. 1, the_scatterometer_includes_illumination optics 10 configured_to direct light to polarizing component_12, which may be a rotating_polarizer. Light from polarizing component 12 is_directed to non-PBS 14, which directs_the light to objective lens_16. Objective_lens 16 directs the light_to wafer 18._Light scattered_from wafer 18_is collected by objective lens 16_and directed by_non-PBS 14 to polarizing component 20._Polarizing_component 20 may_be_a_rotating analyzer._Light exiting polarizing_component_20 is_directed_to collection optics 22.
There are several_disadvantages_to the above-described scatterometers. For example, rotating_optical components is relatively_slow._In addition, precisely rotating_optical components can be difficult._Furthermore, non-repeatability in the rotation of_optical components_can degrade_system calibrations. Using separate optical components to establish illumination and collection_polarizations also makes precise alignment of_the collection and illumination_polarization axes_difficult._In addition, the_polarization_purity of_half-wave plates and electro-optical retarders such as_Pockels cells_and liquid crystals is poor. Switching_lasers on and off_electronically_also reduces stability and repeatability.
Accordingly, it_would be advantageous to develop scatterometers_that overcome the shortcomings of_speed_of_measurement and ease and stability_of calibration inherent in previously used_architectures without reducing_the information content generated by continuous motion_polarizing_instruments such as rotating polarizer and_rotating_analyzer scatterometers. The present invention relates_to_an_automated apparatus for retrieving liquid_samples such as pretreated blood serum_from a multiplicity of sample tubes or vials so_that the withdrawn_samples can subsequently be tested_and_analyzed.
There_are presently a large number of routine clinical tests, such_as blood_tests in which_fluid samples, e.g. blood samples are placed in a test_tube or vial. The samples are appropriately_treated, for example to separate the serum from the red blood_cells, additives for the tests are added to_sample, and thereafter the actual tests are_performed, either