Kehityshistoria
Laserteknologia ilmestyi 1960-luvulla, ja sen varsinainen sovellus alkoi 1970-luvun alussa. Varhaisin laserlähetin oli sähköinen laserputki, joka oli täytetty helium-neon(He-Ne)-kaasulla, joka oli aina käytännöllinen,laktinen geeli.
Inthelate1970s,semiconductortechnologytendedtomature.Semiconductorlaserswereborn,andhigh-sensitivityphotosensitivematerialswerecontinuouslydiscovered.Coupledwiththedevelopmentoflasercontroltechnology,lasertechnologymaturedrapidlyandenteredthefieldofpracticalapplications.
ScientificresearchersrepresentedbytheUnitedStatesandJapanhavecombinedlasertechnologyandcomputertechnologyonthebasisofelectrostaticcopiers,andhavesuccessivelydevelopedsemiconductorlaserprinters.Thistypeofprinterhasgoodprintingquality,fastspeedandnonoise,soithasbeenwidelyusedsoon.
Periaate
Ohjauslaitteen koostumus, suunnittelurakenne, ohjausmenetelmä ja komponentit ja lasertulostimen työprosessin vaatimat osat vaihtelevat eri merkkien ja mallien mukaan.
①Thechargingpolarityofthephotosensitivedrumisdifferent.
②Thepartsusedtochargethephotosensitivedrumaredifferent.Somemodelsusethewiredischargemethodtochargethephotosensitivedrum,andsomemodelsuseachargingrubberroller(FCR)tochargethephotosensitivedrum.
③Korkean paineen siirrossa käytetyt osat eroavat.
④Theexposuremodeofthephotosensitivedrumisdifferent.Somemodelsuseascanningmirrortodirectlyscanandexposethephotosensitivedrum,andsomemodelsuseascannedreflectedlaserbeamtoexposethephotosensitivedrum.
However,theyworkbasicallythesame.Thelaserbeamemittedbythelaserisinjectedintotheacousto-opticdeflectionmodulatorthroughthemirror.Atthesametime,thebinaryimageandtextlatticeinformationsentbythecomputerissentfromtheinterfacetothefontgeneratortoformthebinarypulseofthedesiredfont.Information,thesignalgeneratedbythesynchronizercontrols9high-frequencyoscillators,whicharethenaddedtotheacousto-opticmodulatorviaafrequencysynthesizerandapoweramplifiertomodulatethelaserbeaminjectedbythemirror.Themodulatedlightbeamentersthepolygonmirror,andthenthelightbeamisfocusedbythewide-anglefocusinglensandshotontothesurfaceofthephotoconductordrum(tonerdrum),turningtheangularvelocityscanningintolinearvelocityscanning,completingtheentirescanningprocess.
Thesurfaceofthetonercartridgeisfirstchargedbyachargingelectrodetoobtainacertainpotential,andthenexposedtoalaserbeamcarryinggraphicimageinformationtoformanelectrostaticlatentimageonthesurfaceofthetonercartridge,whichpassesthroughamagneticbrushdeveloperAfterdeveloping,thelatentimageistransformedintoavisibletonerimage.Whenpassingthroughthetransferarea,thetoneristransferredtotheplainpaperundertheactionoftheelectricfieldofthetransferelectrode,andfinallyfixedbythepreheatingplateandhightemperatureheatroller.Thatis,textandimagesarefusedonthepaper.Afterprintingthegraphicinformation,thecleaningrollerremovesthetonerthathasnotbeentransferredaway,thedischargelampremovestheresidualchargeonthedrum,andthecleaningpapersystemisthoroughlycleanedtoenteranewroundofworkcycle.
Thelightsourcethatproduceslaserlightisobviouslydifferentfromordinarylightsources.Forexample,anordinaryincandescentlightsourceheatstheatomsofthetungstenfilamenttoanexcitedstatethroughelectriccurrent,andtheatomsintheexcitedstatecontinuouslyemitlightbyspontaneousemission.Thiskindofordinarylightsourcehasgreatscatteringanddiffusivity,andcannotbecontrolledtoformaconcentratedlightbeam,soitcannotbeusedinlaserprinters.Thelaserbeamrequiredbythelaserprintermusthavethefollowingcharacteristics:
①Highdirectivity.Theemittedlightbeamisnotscatteredanddiffusedwithinacertaindistance.
②Highmonochromaticity.Purewhitelightiscomposedofsevencolorsoflight.
③Highbrightness,whichisconducivetotheconcentrationofthebeamandhashighphysicalenergy.
④Highcoherence,easytostackandseparate.Thelaseristhelightsourceofthelaserscanningsystem,whichhasthecharacteristicsofgooddirectivity,strongmonochromaticity,highcoherence,concentratedenergy,andconvenientmodulationanddeflection.Theearlylaserprintersmostlyusedhelium-neon(He-Ne)gaslaserswithawavelengthof632.8nm,whichwerecharacterizedbyhighoutputpower,largevolume,andlonglife(generallygreaterthan10,000hours),reliableperformance,andnoiseLow,highoutputpower.Butbecauseofitslargesize,ithasbasicallybeeneliminated.Laserprintersusesemiconductorlasers,themostcommonisthegalliumarsenide-galliumaluminumarsenic(GaAs-GaAlAs)series.Thewavelengthoftheemittedlaserbeamisgenerallynear-infraredlight(λ=780nm),whichcanbecomparedwiththewavelengthsensitivitycharacteristicsofthephotosensitivedrumMatch.Thesemiconductorlaserissmallinsizeandlowincost,andcanbedirectlymodulatedinternally.Itisthelightsourceofaportabledesktoplaserprinter.
Laserscanningisusedtoproduceverysmallhigh-precisionlightspots,whichareusedforhigh-qualitytextandimageprinting.Theprincipleofcommonlyusedlasergenerationis:twopiecesaresetparalleltoeachotheratbothendsoftheworkingmaterialMirror(grid),aresonantcavityisformedbetweenthetwomirrors.Onereflectoroftheresonantcavityisatotalreflector,andtheotherisahalfreflector.Whentheworkingsubstanceisexcited,thephotonsemittedbytheatomspontaneouslyreflectbackandforthintheresonantcavity,andtheradiatedphotonscontinuetoincrease.Whenthesuperimposedphotonsintheresonantcavityincreasetoacertainamount,itwillpenetratethesemi-reflectivemirrorandemitaverystronglight,whichisthelaser.Thelightbeamsemittedinthiswayareveryconcentrated,andthereisalmostnoscattering.Aslongasweusecontroltechnologytocontrolthewavelengthofthelightwaveat700-900nm(nanometers),thelaserproducedcanmeettheexposureneedsofthephotosensitivedrumofthelaserprinter.
Modernsemiconductorlasersusuallyuselaserdiodes.Itsprincipleisverysimilartoordinarydiodes.Forexample,thereareapairofPNjunctions.Whenvoltageandcurrentareappliedtothelaserdiode,theP-typesemiconductormaterialTheholesintheN-typematerialandthefreeelectronsintheN-typematerialproducerelativemotion.ThecarrierdensityatthePNjunctionincreasesverygreatly.Thefreeelectronsandholesrecombine,therebygeneratingstimulatedradiationandreleasingphotonswithlasercharacteristics.Itisreflectedbythereflectorinthelaserresonantcavity,andemitsthelaserbeamthroughthelaserholeandthefocusingmirrorinthehole.
Itcanbeseenfromthegenerationoflaserthatalaserbeamonlyincludeslightofonemainwavelength,whichismonochromatic.Eachraytravelsinonedirectionandiscombinedinasuperimposedmanner,whichwecall"coherence".Thisfeatureallowsthelasertohitatargetinaverythinbeamwithalmostnoscattering.Eachlaserbeamislikeabulletshotoutofthebarrel,andeachbulletcanonlypunchoneholeinthetarget.Ifyouwanttotypea"one",youhavetoshootalotofbulletsandpunchalotofholesalongthedirectionofthe"one"toformahorizontalarrangementof"one"dots.Thisiswhatwecall"dotmatrixarrangement".Itisthetechnicalbasisforthe"dotmatriximage"tobediscussedlater.
Thegraphicinformationoflaserprinterisalsocomposedofdotmatrix.Thehighertheprintingqualityrequirements,themoredotsthatmakeupacharacter.Therearefourmethodsforlaserscanningdotmatrixformation.Single-linescanning:Sendthedotmatrixinformationofeachlineofalineofcharacterstothescannerforscanning,whichiscalledsingle-linescanning.Multi-linesequentialdeflectionscanning:Thehigh-frequencysignalgeneratorgenerates9differentfrequenciesinturn.AccordingtotheprincipleofBraggdiffraction,theywillgenerate9scanlineswithdifferentdeflectionanglesinthedeflectionmodulator,andthentherotatingmirrorrotatesasmallangle,Scanoutthedotmatrixinformationfromlefttoright.Becausethismethodonlyneedstorotatethemirrorthroughatinyangle,whichisequivalentto1/132ofthesingle-linescanningmethod,itcanform1character,soitisalsocalledsmallrasterscanning.Multi-linesimultaneousdeflectionscanning:referstothesimultaneousgenerationof9differentfrequenciesinthehigh-frequencydrivecircuit,whicharesynthesizedandsenttothedeflectionmodulator.Multi-linesimultaneousdeflectionscanning:Thismethodisofthesametypeasthemulti-linesimultaneousdeflectionscanning,exceptfortheformationofonecharacter.Thatis,whenscanninghighdotmatrixcharacters,acompletecharacterisdividedintomultiplescans.Thedotmatrixformationofgraphicinformationisbasicallysimilartothedotmatrixformationofcharacters.
Photosensitivedrum
Thephotosensitivedrumisthecorecomponentofalaserprinter.Itisaphotosensitivedevice,mainlymadeoflightguidematerial.Itsbasicworkingprincipleistheprocessof"photoelectricconversion".Itisusedasaconsumablematerialinlaserprinters,anditspriceisrelativelyexpensive.Photosensitivesemiconductorshavethecommonalitiesofsemiconductors,suchasbeingexcitedbyheatandchangingconductivityafterdoping.Inaddition,italsohas"photoconductivity"characteristicsthatothersemiconductorsdonothave.Afterthephotosensitivesemiconductorisirradiatedwithlight,itsconductivitycanrisebyseveralordersofmagnitude.Intermsofenergyband,theelectronsinitsvalencebandabsorbtheenergyoflightandthenjumpintotheconductionbandtoproduceelectron-holepairs.Thiselectron-holepairproducedbylightiscalled"photo-generatedcarrier".Asthe"photo-generatedcarriers"generatedinthephotosensitivesemiconductorincreases,itsconductivityrises.Thisincreasedconductivityafterexposuretolightiscalled"intrinsicphotoconductivity."Inpracticalapplications,photosensitivesemiconductormaterialsneedtobedopedbeforetheycanbemadeintosemiconductormaterialsusedinlasers.Therefore,inadditiontotheintrinsicphotoconductivity,thephotoconductivityoftheimpurityformedbylight-excitedelectronsorholesattheimpuritylevelmustalsobepossessed.Insomephotosensitivesemiconductors,"impurityphotoconductivity"playsamajorrole.
Afterthephotosensitivesemiconductorisirradiatedwithlight,itwillchangethe"carriermobility"intheobjecttovaryingdegrees(mobilityistheratioofthecarrier'smigrationspeedtotheexternalelectricfield).The"conductance"thatmarkstheconductivityofanobjectisequaltothecarrierdensitymultipliedbythemobility.Asthemobilityincreases,theconductivityincreases.Theconductivityisdeterminedbythevaluesofintrinsicphotoconductivity,impurityphotoconductivityandmobility,butundercertainconditions,oneofthesefactorsisthemainfactor.
Variouslightconductorsinpracticalapplicationshavedifferentsensitivitytolight.Theelectricalconductivityofthelightconductorisdirectlyproportionaltoitssensitivitytolight.Therefore,thelightperceptionhasagreatinfluenceontheconductivityofthephotoconductor.Thesensitivityoflightconductorstolightisdifferent.Acertaintypeoflightconductorhashighsensitivitytolightinacertainregionofthespectrum.Ifitleavesthisregion,itmayloseitssensitivity.
Thephotosensitivesemiconductorwillformanabsorptionpeakforlightinthewavelengthrangeoflightapplicabletoit.Thephotoconductivityeffectisbestinthispeakrange.Itisalsorelatedtotheilluminanceoflight.Thehighertheilluminance,themorecarriersaregenerated,andthehigherthephotoconductivity.However,thecharacteristicsofeachphotoconductoraredifferent,sounderthesameconditions,theilluminancerequiredtoachievethesamephotoconductivityindexisdifferent.
Thecommonlyusedphotoconductivematerialsforphotosensitivedrumsarecadmiumsulfide(CdS)andselenium-arsenic(Se-As).Organicphotoconductivematerials(opc)andotherseveral.Thelightguidematerialusedintheproductionofphotosensitivedrumsshouldhavethefollowingcharacteristics:
①Goodwearresistance.Thesurfaceofthephotoconductormusthaveacertaindegreeofhardness,anditmustbeabletowithstandthemechanicalabrasionduringthedevelopment,transferandcleaningprocess.Ifthephotosensitivedrum(photoconductor)iswornorscratched,itwillcausethedeteriorationoftheprintqualityordamagethephotosensitivedrum.Ifitisseverelyworn,itwillonlybescrapped.Inactualwork,mostofthephotosensitivedrumsarescrappedduetowearandscratches.Anewtypeoflong-lifeceramicphotosensitivedrum(a-Si)hasbeenapplied,whichcanprintmorethan300,000sheets.
②Goodtemperaturestability.Theperformanceofthephotoconductoriseasilyaffectedbytemperature.Therefore,intheperformanceofthelaserprinter,itisparticularlyemphasizedthattheoperatingenvironmentmusthaveasuitabletemperatureandhumidity,otherwiseitwillaffecttheprintquality.
③Goodphotoconductivity.Photoconductivityisanimportantindicatorofthephotosensitivedrum,whichdirectlyaffectsthequalityofprinting.Becausethephotosensitivedrumiscontinuouslyworkinginthecycleofcharginganddischarging,itisrequiredthatthepotentialrisesquicklyduringcharging,andthesurfacesaturationpotentialishigherthantheappliedpotential;otherwise,theinitialpotentialwillnotrise,whichwillalsoaffecttheprintquality.Thedarkattenuationofthephotosensitivedrumafterchargingshouldbesmall,otherwisethesurfacepotentialcannotbemaintainedandthenecessarypotentialdifferencelatentimagecannotbeformed.Thephotosensitivedrumdischargesquicklyafterexposure,thatis,thelightdecaysquickly.Themorethoroughthedischarge,thebetter.Becausetheamountofresidualpotentialnotonlyaffectsthecontrastofthelatentimage,butalsobringsaboutthe"graybottom"oftheprintedproduct.
④Resistanttofatigue.Intheprocessofusingthephotosensitivedrum,theprinterhastochargeitrepeatedly,soitmusthavegoodfatigueresistance.Duringthespecifiedlifetime,theprintqualitycannotbereducedduetocontinuoususe.Thephotosensitivedrumhasbetterstabilityoflightguidecharacteristicsandshouldmeettherequirementsofcontinuoususe.
Thephotosensitivedrumusedinlaserprintersgenerallyhasathree-layerstructure.Thefirstlayerisanaluminumalloycylinder(conductivelayer),thesecondlayerisavacuumevaporationmethodonthesurfaceofthecylinder,coatedwithalayeroflightconductormaterial(lightguidelayer),andthethirdlayerisontheoutsideofthelightguidematerialPlatingalayerofinsulatingmaterial(insulatinglayer).Inordertobetterdischargethecharge,somephotosensitivedrumsarecoatedwithalayerofsuperconductingmaterialbetweenthephotoconductivelayerandthealuminumalloyconductivelayertoreleasethechargemorequickly.
Theinsulatinglayeronthesurfaceofthephotosensitivedrumistoimprovethewearresistanceandincreasetheservicelife;theotheristoprovideprotectionforthephotoconductorlayer,preventtheabrasionofthephotoconductor,andmaintainthephotoconductivityofthephotoconductor.
Theconductivelayeraluminumalloycylinderisconnectedwiththegroundwireofthelaserprinter,sothatthepotentialafterexposureisquicklyreleased.Itisaveryhigh-precisioncylinderthatcanmaintainauniformspeedandmaintainauniformchargeduringoperation.
Asanimportantpartoflaserprinters,theratedlifeofphotosensitivedrumsisgenerallyabout6000to10000sheets.Whentheprintimageisfoundtobelight,light,uneven,andcausedbynon-transfercoronaelectrodeandtoner,itmeansthatthelifeofthephotosensitivedrumhasexpiredandshouldbereplaced.
ThefollowingtakesthecommonlyusedHP6Lprintertonercartridgeasanexampletointroducehowtoreplacethephotosensitivedrum:
Firstofall,cutoffthepowersupplyoftheprinterandtakethetonercartridgeoutoftheprinter.,Andthenusediagonalplierstoclampthemetalpinononeside,andcarefullypullitout(oruseanailtoputthemetalpinintothetonercartridge,andthemetalpincanbetakenoutafteropeningthetonercartridge).AfterpullingoutthesilvermetalpinsonbothsidesThetonercartridgecanbedividedintotwoparts.Thesidewithlightbluephotosensitiveseleniumisthewastetonercollectionpart,andthesidewiththemagneticrolleristhetonersupplypart.
Thenunscrewthescrewonthegearlesssideofthepartofthemagneticrollerthatsuppliesthepowder.Afterremovingtheplasticshell,youcanseeaplasticcover.Opentheplasticcoverandplacethetonercartridgeonthemagneticroller.Cleanupallthetoner,besuretocleanupalltheremainingtoner,itisbesttouseavacuumcleaner.Theninstallthemagneticrollerinthereverseorderofthepreviousone.Atthistime,applyforcetopressthemagneticrollertopreventthemagneticrollerfromleavingitsoriginalposition.Shakethetonerevenlyandslowlypouritintothetonersupplybin.Afterputtingontheplasticcoverandtheplasticshell,payattentiontoalignthesemicircleontheendofthemagneticroller'scentralshaftwiththesemicircularholeontheplasticshell.Gentlyturnthegearonthesideofthemagneticrollerseveraltimestomakethetonerevenly.
Nowwehavereachedthemostimportantstep-replacingthenewphotosensitivedrum.Usediagonalplierstopulloutthefixingpinofthewastetonercollectingpartthatfixesthephotosensitivedrum.Note:Donotusenailstodrivethefixingpinintothetonercartridge.Afterpullingoutthefixingpin,theoldphotosensitivedrumcanbetakenout,andthenthewastetonercollectingpartCleanupthewastepowder.Replacethenewphotosensitivedruminthereverseorderofdisassembly.Wheninstallingthephotosensitivedrum,payattentiontotheleftandrightpoints.Installthesidewiththegearbuttthegroove.Thenfixthephotosensitivedrumwiththefixingpins.Thenewlypurchasedphotoconductordrumhasablackanti-exposureseal.Donotremoveitbeforeinstallationtopreventexposure.Itcanberemovedonlyaftertheinstallationiscomplete.Finally,installandrestorethetonersupplypartandwastetonercollectionpartaccordingtothepositionswhentheyweredisassembled,insertthemetallatchesonbothsides,andthenstartprinting.
Translation
(1)Datatranslation:Toprintacompletetextandimage,inadditiontothefunctionsofthelaserprinteritself,thecontenttobeprinted,thatis,textorimage,mustalsobeprintedthroughthecomputerUsewordprocessingsoftwareorgraphicsprocessingsoftwaretoeditintoacomputerlanguagewithacertainformat.Thecontentofthedescriptionisdeterminedbythecomputereditingsoftwareandhasnothingtodowiththelaserprinter.WhenweselecttheprintercommandandpresstheOKandprintbutton,thecomputersendstheediteddatatotheprinterthroughtheprinterinterface,andtheprinterdriverinterpretstheprintedcontentandconvertsitintoalanguagethattheprintercanrecognize(alsoCalledprinterlanguage),theprinterwillprintouttheeditedtextorimageinitsownlanguage.
Differentmodelsoflaserprintershavedifferentprintinglanguagesanddifferentdrivers.Ofcoursetherearealsocompatibleprinterdrivers.ThelaserprintersproducedgenerallyusethestandardprintinglanguagePCL5orPCL6.
(2)Datatransmission:Therearemanykindsofcommunicationtransmissionportsbetweentheprinterandthecomputer,themorecommononesare"serialport"or"parallelport".EPP/ECP(EnhancedParalleIPort/ExtendedCapabilitiesPort)iscalledanenhanced/extendedparallelport."Serialport"isgenerallyrarelyusedduetoitsslowerspeed.Others,suchastheSCSIinterface,aremostlyusedinhigher-endprintersduetotheirfastspeed.Someprinterscommunicatewiththecomputerusingthevideointerface(VDO)method.Thecommunicationmethodisdifferentfromotherinterfaces.Ittransmitsnotdata,butalaserbeam,whichisfaster.Itsdataiscompletedbyanother"videoconversioncard",butbecauseitsharesmemorywiththecomputer,itrequiresthecomputertohaveenoughbufferspace.Thegeneralprintingandtypesettingindustryusesmoreprintersofthistypeofinterface.Somehigh-endprintershavemultipleinterfacesandcanconnecttomultiplecomputersatthesametime.ManyprintersproducedareequippedwithfasterUSBports.
Whentheprintcontrollerreceivesdatafromthecomputer,theprintergenerallyadoptstwoworkingmethods:oneistosendthedatadirectlytotheinterpreterforprinting,whichiscalled"segmentworkingmode",whichworksTheprinterdoesnotneedalotofcacheandmemory,andmostordinaryprintersusethiswayofworking.Theotheristostorethetransmitteddataintheharddiskinsidetheprinterandprintitoutatanytimewhenitisreadytobeused.Itisalsocalled"poolmode",whichisusedbymanyhigh-endprinters.Itsadvantageisthatwhenmanyusersshareaprinter,theycanissueprintcommandsatthesametimewithoutwaiting,andcansavethewaitingtimeofdatacommunicationtransmission,butitspriceisalsomoreexpensive.[Alsocalleddotmatrixgraphics),similartoordinarydotmatrixprinting.Theformeristorealizethedotmatrixarrangementbycontrollingtheonandoffofthelaserbeam,whilethelatteristorealizethedotmatrixarrangementbystrikingtheprintingneedle.
Rasterimageisakindofvideodigitalimage.Therasterconverterintheprinterneedstorasterizethevideodataandconvertitintoadotmatriximageusedbytheprinterforprinting.Theso-calledrasterimageiscomposedofindependentdots.Compositionofimages.Forexample,imagesprintedonnewspapersordisplayedonTVscreensarerasterimages.
Thedotmatrixarrangementoflaserprintersiscontrolledbyasquarematrixcomposedofbinarydata.Eachdotcorrespondstoabinarydigit.Thearithmeticcontrollercontrolsthelasertoemitalaserbeamtothesurfaceofthephotosensitivedrum,whichiscalled"exposure",theexposed"dots"arecalled"pixels".Toprintatextoranimage,alotof"pixels"arerequired.Therefore,thegreaterthenumberofpixelsperunitarea,thehighertheresolutionofprinting.Ifalaserscanningdeviceshoots300dotsperinchalongthehorizontalsurfaceofthephotosensitivedrumaxis,andthephotosensitivedrumisdrivenbythemainmotortorotateataconstantspeedof1/300minutes,thenthelaserprintercanbe300×300DPIpersquareinchResolutionprintstextorimages.Theoutputaccuracyofhigh-endlaserprinterscanreach2400DPI.Thedotmatriximageisformedbythepixels,anditisalsocompletedbytheacousto-opticmodulator,high-frequencydriver,scannersynchronizerandopticalsystem.
Modulator
Asyouallknow,theimagesandsoundsreceivedbytheTVareemittedbytheTVstationbymodulatingthesoundandlightsignalsintoelectricalsignals.TheelectricalsignalreceivedbytheTVisdemodulatedandrestoredtoimageandsound.Thelightbeamemittedbythelaserofthelaserprinteralsocarriesdatainformation,andtheconversionprocessofthisinformationisalsosimilartotheinformationtransmissionprocessofaTV.Butthisprocessisconvertedbytheacousto-opticmodulator.
Themodulationfrequencyoftheacousto-opticmodulatorcanreachabout30MHz,andthecharacteristicsarestable.Therefore,mostlaserprintersusethismodulator.Theworkingprincipleoftheacousto-opticmodulatoristousethecharacteristicsofBraggdiffractionproducedbytheacousto-opticeffecttorealizethecontrolofthepropagationdirectionofthelaserbeam.Tocompletetheimagingtaskofthegraphicinformation,thelaserbeammustbemodulatedwiththegraphicinformation,justasthetelevisionstationmodulatestheimageandsoundsignalstotheradiowavetodemodulatetheimageandsoundsignalsintheTV.
Theworkingprincipleoftheacousto-opticmodulatoristousetheacousto-opticeffecttogenerateBraggdiffraction.Ifultrasonicwavesaregeneratedinultrasonicmediasuchasglassandcrystals,itwillcauseperiodicrefractiveindexchangestobecomephases.Thegratingconstantisequaltothewavelengthoftheultrasonicwave.Whenthelaserbeamhitstheultrasonicmedium,thelaserbeamwillbediffracted.Theintensityanddirectionofthediffractedlightwillchangewiththefrequencyandintensityoftheultrasonicwave,whichistheacousto-opticeffect.
Whentheultrasonicwaveisemittedtoglassorcrystalandreflected,thelightrefractedbytheincidentanglepropagatestoformadiffractiongratingwithaphasechange.Thegratingconstantisequaltothewavelengthλoftheultrasonicwave.Ifthelaserbeamisinjectedintotheultrasonicmedium,thelaserbeamwillbediffracted,andtheintensityanddirectionofthediffractedlightwillchangewiththefrequencyandintensityoftheultrasonicwave.Thisistheacousto-opticeffect.Accordingtothestrengtheningconditionsofwaveinterference,thedirectionsofincidentlightanddiffractedlightsatisfytheBraggequation:
θi=θd=θB
sinθB=λ/2A=λf/2v(v=fA)
jossa:θi:tulevan valon jaultraäänipinnan välinen kulma;λ:valon aallonpituus keskiössä;θd:hajotun valon ja ultraäänipinnan välinen kulma;A:ultraääniaallonpituus;θB:tsamm. λf/2v,kun taittuneen valon ja tulevan valon välinen kulma onα, niin :α=θi+θd=2θB=λf/v.Kaavassa αonpoikkeutuskulma,joka on verrannollinenultraäänen taajuuteen.Ultraäänitaajuuden muuttaminenfvoi muuttaapoikkeutuskulmaaα,niin saavuttaaasennonohjauksen tarkoituksen.
AccordingtotheBraggdiffractiontheory,whenultrasonicwavesmaintainahigh-frequencysignalofonefrequency,theincidentlaserbeamproducesafirst-orderdiffractedlightinadditiontoazero-orderlight.The0-orderlightcontrolsthestartandstopofthesynchronizerandthehigh-frequencysignal,andthefirst-orderdiffractedlightexposesthephotosensitivedrumtoformpixels.
Scanner
Tomakethelaserbeamaftertheacousto-opticmodulatorproducetextorimagesonthephotosensitivedrum,thelaserbeamneedstocompletethemovementinboththehorizontalandverticaldirections.Itdependsonthemovementofthelaser,becausethevibrationcausedbythemovementoftheoptoelectronicdevicewillaffecttheaccuracyofthelaserbeam.Therefore,thelaserofthelaserprinteradoptsafixedstructure,andamulti-sidedrotatingmirrorcompletesthehorizontalscanningofthelaserbeam,andtheverticalscanningisrealizedbytherotationofthephotosensitivedrum.
Tomakethemodulatedlaserbeamproducetextandimagesonthephotosensitivedrum,thehorizontalmovement(inthedirectionoftheprintingpaperline)andverticalmovementshouldbecompleted.Thelongitudinalmovementiscompletedbytherotationofthetonercartridge,whilethelateralmovementofthebeamiscompletedbythescanner.Scannersaredividedintoacousto-optic,electro-optical,galvanometer,androtatingmirroraccordingtotheirworkingmethods.Inviewoftheadvantagesofrotatingmirrorscanners,suchaslargescanningangle,highresolution,lowlightenergyloss,andsimplestructure,theyarewidelyusedinlaserprinters.Inordertoreducethenonlinearerrorgeneratedwhenthepolygonmirrorrotates,thegeometricaccuracyerroroftherotatingmirrorandtheunstablerotatingspeedoftherotatingmirrordrivemotor,thelongitudinalspacingandtheuneventrajectoryofthecharacterscausedbytheshortcomingsaregenerallyinstalledinthescanner.Asyncsignalsensor.Thissensorusesthezero-orderlightgeneratedbyBraggdiffractionwithoutdeflection,soithasthecharacteristicoffixedirradiationpositionafterbeingreflectedbythepolygonmirror.Itisusedasasynchronizationsignaltocontrolthestartandstopofthehigh-frequencysignalgenerator.Ensurethatthescanningdistanceisconsistentandeliminatetheabove-mentionederrors.
Inordertointegratethescanningbeamgeneratedbythescannerintoaspecifiedsizeandperformauniformlinearmotiononthephotosensitivedrum,abetteropticalpathsystemshouldbeused.Theopticalpathsystemisdividedintotwotypes:frontandrearobjectivelensaccordingtothelens'sfrontandrearpositionofthescanner.Sincetherearobjectivelenshasseriousdistortionwhenscanninglargerimages,itisrarelyused.Thescanninglineinfrontoftheobjectivelensisrelativelystraight,butthereisdistortion.Sincethelaserprinterproducedlaterusesawide-anglefocusinglenscombinedwithmultiplelenses,thefocallengthis300mm,andtheobjectdistanceofthepolygonmirroris37mm.ThedistortionisItisonly0.0011%,whichcanfullymeettherequirementsoflaserimaging.
Thepolygonalscanner(mirror)usedinlaserprintersgenerallyhasthreekindsofmirrors,two-sidedmirror,four-sidedmirror,andsix-sidedmirror.Thescanningmotordrivestherotationtocompletethehorizontalscanningmovement.Itisakeycomponenttoensuretheprintingaccuracyoflaserprinters.Theprincipleofthescannertocompletethehorizontalscanningis:WesetMNasamirrorofthescanner.WhentheincidentlaserbeamhitspointAontheMNsurface,iftheincidentangleisθ?i,thereflectedbeamwillbereflectedatthereflectionangleθ?d,θ?i=θ?d,whenMNrotatesthroughanangleφ,Whilethedirectionoftheincidentbeamremainsunchanged,thereflectedbeamrotatesby2φ,thatis,thereflectedbeamrotatesattwicetheangleofMN.IfPisthereflectedlightspotatoneendofthephotosensitivedrum,andP1isthereflectedlightspot,thelateralscanningofthephotosensitivedrumiscompletedattheotherendofthephotosensitivedrum.Ofcourse,therotationspeedofthescannerisextremelyfast,soP～PAlotofreflectedlaserbeamspotsarealsoformedbetween?1.Whenthemainmotordrivesthephotoreceptordrumtorotate,italsocompletesthelongitudinalscanningofthereflectedlaserbeamspot,thusfinallycompletingthedotmatrixarrangementofthetextorimage.
Opticalsystem
Inordertomakethelaserbeamreflectedbythescannergathertoformalightspotofaspecifiedsize,andeliminatethediffusionofthebeamduringthepropagationprocess,asetofopticallensesisneeded.Thebeamismodulatedtoimprovescanningaccuracy.Itincludes:curvedlens,sphericallens,reflector.Thisgroupoflensescanonlymeetthetechnicalrequirementsoflaserimagingifthedistortionofthelaserbeamiscorrectedto0.1‰.
Visualizationsystem
Laserprinterisasophisticatedmechanicalsystemthatusesthephysicalandchemicalprinciplesoflight,electricity,andheattooutputtextorimagesthroughinteraction.ThesecomplexprocessesareItisrealizedbyanelectroniccontrolsystem,calledanelectronicimagingsystem.Thetheoryof"electrostaticimaging"wasfirstproposedbyAmericanCarlson,soitisalsocalledCarlson'smethod.Orcalledtheelectricdischargeimagingmethod.Thebasicprocesscanbedividedinto7stepsofcharging,exposing,developing,transferring,fixing,cleaning,andde-energizing,ofwhich5stepsarecarriedoutaroundtheelectronicimagingsystem.
Luokittelu
Lasertulostimet voidaan jakaa kolmeen luokkaan niiden tulostusnopeuden mukaan: hitaat lasertulostimet (tulostus 10-30 sivua minuutissa); keskinopeat lasertulostimet (tulostusminuutti 40-120 sivua);nopeat 0 sivua 3 minuuttia.
Structure
Laserprinteriscomposedoflaser,acousto-opticmodulator,high-frequencydrive,scanner,synchronizerandopticaldeflector.ItsfunctionistosendtheinterfacecircuitThebinarydotmatrixinformationismodulatedonthelaserbeam,andthenscannedontothephotoreceptor.Thephotoreceptorandthecameramechanismformanelectrophotographictransfersystem,whichtransferstheimageandtextshotonthephotoreceptordrumtotheprintingpaper.Theprincipleisthesameasthatofacopier.Thelaserprinterisanon-impactoutputdevicethatcombineslaserscanningtechnologyandelectronicimagingtechnology.Ithasdifferentmodelsanddifferentprintingfunctions,buttheworkingprincipleisbasicallythesame,andithastogothroughsevenprocesses:charging,exposure,developing,transfer,discharging,cleaning,andfixing,ofwhichfiveprocessesarecarriedoutaroundthephotosensitivedrum..Whenthetextorimagetobeprintedisinputintothecomputer,itispreprocessedbycomputersoftware.Thenitisconvertedbytheprinterdriverintoaprintcommand(printerlanguage)thattheprintercanrecognizeandsenttothehigh-frequencydrivecircuittocontroltheonandoffofthelaseremittertoformadotmatrixlaserbeam,andthentheelectronicimagingsystemthroughthescanningmirrorThephotosensitivedruminthephotoconductivedrumperformsaxialscanningexposure,andtheverticalscanningisrealizedbytherotationofthephotosensitivedrumitself.
Precautions
Becauselaserprintershavehigh-voltagecircuitsandhigh-temperaturecircuits,bothelectronicradiationandthermalradiationhaveacertainimpactonthehumanbody.Payattentiontotheprotectionorprotectionofpregnantwomenandyoungchildren.Stayawayfromthesedevices.Duringtheprintingprocess,hightemperatureheatingwillbringoutsomepowderandinkparticles,whichisnotgoodforbreathing,soyoushouldtrytoavoidworkingatthelaserprinterforalongtime.
Charging
Thephotoconductormaterialonthesurfaceofthephotosensitivedrumisaninsulatorwhenitisnotexposedtolight,anditisinaneutralstatewithoutanycharge.Torealizethe"electrostaticlatentimage"onthesurfaceofthephotoconductor,thesurfaceofthephotoconductormustbechargedtomakeitcharged.Onlyinthisway,whenthelaserbeamscansontothelightconductor,theexposedpointsofthelightconductorareturnedontoformabeamdotmatrix.Thedotmatrixchargeconductswiththesubstratetoforma"potentialdifferencelatentimage".Whenthephotosensitivedrumrotatestoapositiontangenttothedevelopingmagneticroller,thetoneronthemagneticrollerwiththeoppositechargepropertiesofthephotoconductorsurfaceisattractedtothesurfaceofthephotosensitivedrum.Asaresult,atonerimageappearsonthephotosensitivedrum.
Tomakethephotosensitivedrumabsorbthetoneraccordingtothegraphicinformation,thetonercartridgeshouldbechargedfirst.Thechargingelectrodeisatungstenwireparalleltothephotosensitivedrumshaftwitha5～7kVDChighvoltage,whenthesurfaceofthedrumisveryclosetothetungstenwire,thesurroundingairisionizedtoproducecoronadischarge,whichmakesthephotosensitivedrumcharged.Thepositiveornegativeofthevoltageisdeterminedbythevoltagecarriedbythetungstenwire.Ifthephotoconductivematerialisselenium-telluriumalloy,itwillbechargedpositively.Afterthephotosensitivedrumrotatesonce,theentiresurfacewillbecharged.
Themethodoflaserprinterchargingthephotosensitivedrumisdifferentdependingonthemodel,butthechargingprincipleisbasicallythesame,allusingDChighvoltagecoronadischargetochargethesurfaceofthephotosensitivedrum.
Earlylaserprintersusedelectrodewireandgridcompositestructuretochargemore,andmostnewlaserprintersusedchargingrubberroller(FCR)tochargethephotosensitivedrum.Whenthehighvoltagegeneratorsendsahighvoltagetotheelectrodewire,astrongelectricfieldisformedbetweentheelectrodewireandthegrid,andacoronaisreleased.Theairbetweentheelectrodewireandthephotosensitivedrumisionized,andtheairionsmigratetothesurfaceofthephotosensitivedrum,sothatthesurfaceofthephotoconductor(photosensitivedrum)isfullycharged.Thismethodcanmakethesurfaceofthephotoconductor(photosensitivedrum)evenlycharged,butatthesametimeitalsogeneratesalotofnegativeions(ozone).Whenozoneaccumulatestoacertainamount,itisharmfultothehumanbody.SuchasCanon'searlyproductsLBP-SXandSTmodels,HP'searlyproductsHP2and3,PanasonicKX6500producedinJapan,LenovoLJ6L,LJ6Pandothermodelsallusethismethodtocharge.
Mostofmodernlaserprintersarechargedbychargingrollers.Becauseofthecontactchargingmethod,thereisnoneedforhighchargingvoltageandnoozoneisproduced.However,duetotheaccumulationofionizeddust,theThewearofthephotosensitivedrumwillalsocauseunevencharging.
Skannausvalotus
Skannausvalotus on aivan kuten käytämmekirjoitusta paperille, jotta se "kirjoittaa"valotuksen valoherkälle rummulle. Tämä tekstiorikuvaSe ei ole näkyvissä. Tätä kutsumme "elektrostaattiseksi latentikuvaksi".
Whenthesurfaceofthetonercartridgepassesthroughthetungstenwireelectrode,itssurfaceischargedwithpositiveelectricity,andnegativeelectricityisinducedattheinterfacebetweenthephotoconductivelayerandthesubstrate.Whenthelightpartofthelaserbeamhitsacertainareaonthedrumsurface,itiscalledexposure.Theresistivityoftheexposedareaissignificantlyreduced,andthepositivechargeonthesurfaceandthenegativechargeontheinterfaceareneutralizedanddisappeared.Duetothegoodinsulatingpropertiesbetweentheselenium-telluriumalloyparticles,thepositivechargeonthesurfaceoftheunexposedsurfaceremainsunchanged.Thatis,alayerofelectrostaticlatentimageisformed.
Scanningexposureistousethephotosensitivepropertiesofthephotoconductivematerialonthesurfaceofthephotosensitivedrum.Whenthephotoconductorisscannedandirradiatedbythelaserbeam,theilluminatedpartisconnectedtotheconductivelayerofthephotosensitivedrumtomakethechargedisappear,andthepartnotilluminatedbythelightstillmaintainsthechargedcharge,thusformingapotentialdifferenceimage,whichcanalsobeunderstoodasThe"discharge"processofthephotosensitivedrum.Duringthede-chargeprocess,thepotentialonthesurfaceofthephotoconductorischanging,andthispotentialchangehasagreatinfluenceontheprintquality.
Whenthesurfaceofthephotosensitivedrumischarged,asthechargeaccumulatesonthesurfaceofthephotosensitivedrum,thepotentialcontinuestorise,andfinallyreachesthe"saturation"potential,whichisthehighestpotential.Thesurfacepotentialwilldecreasewiththepassageoftime.Generally,theworkingpotentialislowerthanthispotential.Thisprocessofnaturaldecreaseofthepotentialwithtimeiscalledthe"darkdecay"process.Whenthephotosensitivedrumisscannedandexposed,thedarkarea(referringtothesurfaceofthephotoconductornotirradiatedbylight)isstillinthedarkdecayprocess;thebrightarea(referringtothesurfaceofthephotoconductorunderthelightirradiation)rapidlyincreasesinthecarrierdensity.Theelectricalconductivityrisesrapidlytoformaphotoconductivevoltage,thechargequicklydisappears,andthesurfacepotentialofthephotoconductoralsodropsrapidly,whichiscalled"lightdecay",andfinallyslowsdown.
Intheory,thefasterandmorethoroughthelightdecayis,thebetter,butinpracticeitisdifficulttoachieve.Theleveloftheremainingresidualpotentialwillaffecttheprintquality.Iftheresidualpotentialistoohigh,thephenomenonofprinting"dust"willappear.Afteranelectrostaticlatentimageisformed,itmustundergoa"development"processasdescribedbelowbeforeitcanbeconvertedintoatonerimage.
Development
The"electrostaticlatentimage"formedonthesurfaceofthephotoconductoris"developed"toshowthetonerimage.Thisprocessiscalled"electronicdevelopment".Thedevelopmentworkiscompletedbythedeveloper,anditsroleistoturntheelectrostaticlatentimageintoavisibleimage.Thedevelopmentisdonebyusingtheprincipleofthesame-sexrepulsionandtheopposite-sexattractionbetweenmaterials.
Thedeveloperisequippedwithironpowderandcarbonpowder.Afterfriction,theironpowderispositivelychargedandthecarbonpowderisnegativelycharged,sothattheironpowderissurroundedbythecarbonpowderandtheironpowderthathasadsorbedthecarbonpowderispermanentlyThemagnetisattractedtoformalayerofironpowderandcarbonpowdermixturesimilartoabrush.Whenthesurfaceofthetonercartridgepassesunderthislayerofmagneticbrush,thetonerisattractedtothepartofthetonercartridgethatisstillpositivelychargedduetothenegativecharge,formingavisibletonerimage.Thefunctionofthestirreristomaketheironpowderandthecarbonpowderfrictionallycharged.
The"electrostaticlatentimage"chargeonthesurfaceofthephotosensitivedrumisoppositetothechargecarriedbythedevelopertoner.Whenthephotosensitivedrumandthemagneticrollercarryingthetonerareclosetoacertaindistance,thetonerwillbeAttraction,orthetonerjumpstothesurfaceofthephotosensitivedrumtoforma"tonerimage",alsoknownasjerkydevelopment.Note:Afterthelaserprinterphotoconductordrumisexposed,thechargeofthe"electrostaticlatentimage"onthesurfaceisnegative,whilethechargeofthetonerispositive.Thetonertransferofthedevelopingunitiscompletedinthisway.
Whenthetonerisevenlystirredinthetonercartridgebytheagitator,thetoneriscarriedbythedopedcarrierandisadsorbedontheoutersurfaceofthemagneticrollerbythepermanentmagneticcoreinthemagneticroller.Nopolarity.Whenthemagneticrollercarriesthetonerandrotatesandtouchesandrubsagainstthetonerscraper,thetonerispositivelycharged.Undertheactionofthetonerscraperandthemagneticfield,thetonerformsathinanduniformtonermistonthesurfaceofthemagneticroller.Thetonerscraperalsoservestolimittheamountoftoner,sothatthetonerdoesnotabsorbtoomuch.
Asmentionedearlier,theresidualpotentialofthephotosensitivedrumisanimportantreasonforthe"bottomdust"inprinting.ThesolutionistoaddappropriateACandDC"bias"tothemagnetrollersleevetooffsetExcessivepowderdelivery.Thedevelopmentbiashastwofunctions.Adjustthedevelopmentbiasappropriately.Oneistoprevent"dust"andtheotheristoadjusttheprintingdensity.Inpracticalapplications,the"printdensity"adjustmentknobistoadjustthedevelopingbias.SomelaserprintermodelssuchasHP,Canon,Epson,andLenovohavethisknob.Buttheincreaseinprintdensityalsomeansthedecreaseinresolution,becausetoomuchtonerwillaffecttheresolutionafterfixing.
Newlyproducedlaserprintersgenerallyhave"resolutionenhancementmode"(RET).ThroughtheRETmethod,thedefectsofthediagonalorarc"dotmatrixholes"canbefilled.REThasnoeffectonthehorizontalandverticaldotmatrix.Ithasthreemodes:①Lighi;②Medium;③Dark.RETcanbecombinedwiththechoiceofprintingdensitytoprintbeautifultextorimages,alsoknownassmoothingtechnology.Withdifferentsettings,thelogoblockontheprintedsampleisdifferent.
Developingmagneticroller:Thedevelopingmagneticrollerisanimportantpartofcarryingtoner.Thepermanentmagneticcoredoesnotrotate.Itsfunctionistousemagnetismtoattracttonertothesurfaceofthemagneticroller.Thesurfaceofthemagneticrollerissprayedwitharoughgraphitelayertoformelectricalcavitieswiththetonerscrapertofacilitatetonertransfer.Whenthemagneticrollerloadedwithtonerrotatesoutofthepositionofthescraper,thetoneronthesurfaceofthemagneticrollerisnotonlycharged,butduetotheforceofthemagneticfield,itformsa"magneticspike",thatis,a"tonermist".Therollerjacketappliesabiasvoltagetoarrangethemagneticspikesinanorderlymanner.Thefunctionofthe"spacer"ofthemagneticrolleristocontroltheeffectiveattractiondistancebetweenthemagneticspikeonthesurfaceofthemagneticrollerandthephotosensitivedrum,whichisbeneficialtoimprovethe"bounceimaging"ofthetoner.
Toner:Thetonerusedinlaserprintersisasingle-componenttoner,andtheprincipleoftheprojectionmethodissimilartotheNPcopier,whichistheNPmethod."Single-componenttoner"isnotwithoutacarrier,becausewithoutabowl,thetonercannotbecarried.Itpowdersthe"carrier"intofineparticlesandmixeswiththetoner.Theparticlesofultrafinetonershouldbelessthan10nanometers.Differentmodelsoflaserprintersusedifferenttonersduetothedifferenceinexposureintensityanddevelopingbiasvoltage,sotheycannotbesubstitutedatwill.Differentmodelshavedifferenttoner"carrier"contentofthesamequality.Someprintersusenon-magnetictoner.
Tyhjennysjärjestelmä
(1)Siirtolaite
Usehigh-voltagestaticelectricitytotransferthe"tonerimage"onthesurfaceofthephotosensitivedrumtoplainpaper,Thisprocessiscalled"transfer".Whenthepositivelychargedtonermovestothevicinityoftheprintingpaperalongwiththephotosensitivedrum,theelectrodeplacedbehindthepaperispositivelycharged.Becausethevoltageisashighas500～1000V,theelectrostaticattractionmakesthepaperclosetothelightguideplate.Thenegativelychargedtonerisadsorbedonthesurfaceofthepaper.Becausethistransfermethodisrelatedtothedegreeofinsulationofthepaper,whenthepaperisdampduetotheweather,thetonerwillnotbecompletelyandtightlyadsorbedonthepaperduetotheleakageofthepapersurface,resultinginpoorprintquality.
Therearetwotransfermethods,oneis"coronadischargetransfer"(wireelectrode),andtheotheris"dischargerubberroller"transfer.Theworkingprincipleofthetwoisthesame.Differentmodelshavedifferenttransfermethods.Theearlyproductionoflaserprintersmostlyusedthecoronadischargetransfermethod.Whenthephotosensitivedrumcarryingthetonerimagerotatestoapositiontangenttothetransferelectrodeortransferrubberroller,apieceofprintingpaperisalsofedbetweenthetwo,andthenthehighvoltageappliedtothetransferelectrodestartsDischarge,whilepushingtheprintingpapertothephotosensitivedrum,thetonerimageonthephotosensitivedrumisattractedtotheprintingpaperduetothetransferofthehigh-voltageelectricfieldonthebottomoftheprintingpapertocompletethesecondarytransferofthetonerimage.Thedischargepolarityofthetransferelectrodewireortransferrubberrolleristhesameandnegative,butthisnegativevoltageishigherthanthenegativevoltageintheexposedareaofthephotosensitivedrum,sothatwhilepushingtheprintingpapertothephotosensitivedrum,italsoreducesThetonerisattractedtotheprintingpaperasmuchaspossible.However,itshouldbenotedthatwhenthetoneristransferredtotheprintpaper,iftheprintpaperisdampandtheinsulationperformanceisnotgood,itwillaffectthetonertransferefficiency,sotherewillbeproblemsofimagedefectandpoorprintqualityofthecharacterhollowchip.
(2) Purkauslaite
Whenthetonerimageistransferredtotheprintingpaper,theprintingpaperisalsocharged.Intheprocessofconveyingtheprintingpaper,electricfieldandfrictionmaydestroythestructureofthetonerimage,soafterthetonerimageistransferred,a"dischargedevice"(dischargerordischargingtooth)isadded,alsocalled"Separateteeth".Itsfunctionistoneutralizethechargeontheprintingpaperandtheadsorbedtoner,eliminatethepolaritytomakeitneutral,andphysicallyadheretotheprintingpaper,therebyensuringtheaccuracyofthetonerimagebeforefixing.Thede-energizationprocessusesACvoltagetoachievethebestde-energizationandneutralizationeffect.
Lämmitys ja kiinnitys
Paperille imeytyvän väriaineen tulostusprosessi painelämpöfuusiomenetelmällä, jolloin sulatettu väri upotetaan tulostuspaperiin kiinteän kuvan muodostamiseksi, jota kutsutaan "kiinnittämiseksi".
Thecarbonpowderadsorbedonthepaperisasmallparticlemadeofthermalresinandcarbonpowder.WhenthepaperwithcarbonpowderpassesthroughtwohighandsmallgapWhenthemetalrolleriscracked,theresininthetonermeltsandispressedtightlyonthepapertogetherwiththetoner,thusformingapermanentimage,andatthesametime,theentirelaserprintingprocessiscompleted.Themeltingtemperatureofthetonerisabout100°C,andthetemperatureoftheheatrollerisrelatedtothespeedofpaperpassing,generallybetween150and180°C.Aftercleaningtheresidualpowderandlight,thephotosensitivedrumentersthenextcycle.
Thelaserprinteradoptsthemethodofcompositehotpressing,andusesthe"fixingcomponent"tocompletethefixation.Theworkingprocessoftonerimagefixingisasfollows:
Whentheprintingpaperloadedwith"tonerimage"entersbetweentheheatingrollerandthepressurerubberrollerinthefixingdevicefromthepaperguide,theheatingrollerItisheatedbytheheatinglamp(185°C),andatthesametime,thetonerismeltedandimmersedintotheprintingpaperduetothepressureofthepressurerubberroller.ThesurfaceoftheheatingrolleriscoatedwithaPTFEcoating,whichmakesitdifficultfortonertoadhere.SomemodelsalsohavealayerofTeflonfilmonthesurfaceofthepressurerubberroller,whichishelpfulforthetoneronthebacksidetonotstickduringdouble-sidedprinting.Afterheatingandfixing,theprintingpaperisseparatedfromtheheatingrollerbytheseparatingclaw,andisledoutbythepaperdischargewheeltocompletethewholefixingprocess.
(1)Lämmitystela
Theheatingrollerismadeofseamlessaluminumalloytube,thewallthicknessofthetubeisbetween1to3mm,andthesurfaceiscoatedwithPTFE.Thispreventsthemeltedtonerfromstickingtotherollerduringfixing.ThePTFEcoatingonthesurfaceoftheheatingrollerwillsoftenslightlyathightemperatures.Whentheprintingpaperisstuckinthefixingdevice,donotusesharphardobjects(suchasscrewdrivers,cameras)toforceitout.Itwilldamagethesurfacecoatingoftheheatingrollerandaffecttheintegrityofthetonerimageafterfixing.
On olemassa monia lasertulostimia, jotka käyttävät kehittyneempiä keramiikkahuijareita (PCT), jotka lämpenevät nopeasti ja säästävät sähköä, kuten HP4L.4P, 5L, 6L, 6P, 2100, 4000, 5000 ja Canon460, 660, 800 korjausta ja korjausta varten.
(2)Lämmityslamppu
Somelaserprintersusehalogenlampswithapowerof350～750W.Theyarefixedinthemiddleoftheheatingrolleranddonotrotatewiththeheatingroller.Aftertheprinterisenergized,theheatinglampisontopreheatthefixingroller.Afterabout1to2minutes,thetemperatureoftheheatingrollerreachesabout185degrees.Whenthesurfacetemperatureoftheheatingrollerreachesthefixingtemperature,thethermistorleaningonthesurfaceoftheheatingrollertodetectthetemperatureinformsthemainlogiccircuittostopheating,andthelampisreadytolightup.Theprintercanstartprinting.Whentheheatinglampisdamaged,thewholemachinewillnotwork,andthemodelwithadisplaypanelwilldisplayanerrorindicationoranerrorcodeof50Error.
(3)Painekumitela
Thepressurerubberrollerisalsocalledthelowerroller,anditsfunctionistocompletethehot-pressfixingandtransferofthetonerontheprintingpapertogetherwiththeheatingroller.Thepressureiscontrolledbythesupportspringsatbothends.Thepressurerollerisgenerallymadeofhigh-temperatureresistantsiliconrubber.Thepressurerollerinsomelaserprintersismadeofhoneycombheat-resistantsponge,andtheoutersurfaceisalayerofPTFEfilm.Itismoreconducivetotheseparationoftheprintingpaperandthepressurerubberrollertopreventpaperjams.
(4)Lämpötilan säädin (termistori)
Mostofthetemperaturecontrolmethodsforlaserprintersusethermalinduction,usingasmallthermistortocontacttheheatingrollertosenseheatingRolltemperature(165～200℃).Thenthelogiccircuitcontrolstheonandoffoftheheatinglamptorealizetheconstantfixingtemperatureofthelaserprinter.Theperformanceofthethermistoristhatthehighertheexternaltemperature,thelowertheresistanceofthethermistor.
Whentheheatingrollerisnotenergized,theresistanceofthethermistorisabout200K,thelogiccontrolcircuit0101isturnedon,thethyristorSSR101isturnedon,andtheheaterstartsheating.Whenthetemperatureoftheheatingrollergraduallyrises,theresistanceofthethermistordecreases.Whenthesurfacetemperatureoftheheaterreachesabout180°C,theresistanceofthethermistoralsoreachesthelowestvalue,about10K,andtheinputvoltageofthethermistortothelogiccontrolcircuitincreases.Afterreachingacertainvalue,0101willbecutoff,andtheheaterwillstopheating.Thisisrepeatedtocontrolthesurfacetemperatureoftheheatertokeepwithinthedesignedtemperaturerange.Thelaserprinterisequippedwithapowersavingfunction(sleepmode).Ifthereisnoprintingwithinasettime,themainlogiccircuitwillcontroltheheatertoenterapowersavingstatetokeeptheheatersurfacetemperatureatabout165°C.Ontheonehand,thiscontrolcansavepowerconsumption.Ontheotherhand,whentheprintjobisrestarted,itcanshortenthewarm-upwaitingtime(thetimetoenterthepower-savingstatecanbeset).
(5)Lämpösuoja (lämpökytkin)
Inordertopreventthetemperatureinthelaserprinterfromrisingunrestrictedlyandburningtheheatinglampandheatingroller,theheatinglampcircuitAthermalprotector(thermalswitch)isconnectedinserieswiththeheatingroller.Insidethethermalswitchthereisasetoflongclosedcontacts,atitaniumsheetandastalk.Titaniumisakindofmemorymetalmaterialwithamemorytemperatureof210°Cduringmanufacture.Ifthetemperaturecontrolcircuitisoutofcontrol,whenthesurfacetemperatureoftheheatingrollerexceedsthesettemperatureof210℃,thetitaniummetalwillshrinkanddeformunderheat,pressingthestrikerbartodisconnectthenormallyclosedcontact,andcuttingoffthecircuitwillprotecttheheater.Whenthetemperatureislowerthan180°C,thetitaniummetalreturnstotheoriginalmemorystate,thenormallyclosedcontactisclosed,andthecircuitisturnedon.Someprintersusefuseprotectors,theprincipleissimilartocurrentfuse.
Cleaningsystem
Themainfunctionofthelaserprintercleaningsystemistoremovethe"residualtoner"thatisnotcompletelytransferredonthesurfaceofthephotosensitivedrum,sothatthenextprintingcyclewillhaveacleanphotosensitivedrum.Theoreticallyspeaking,the"tonerimage"shouldbecompletelytransferred,butitisdifficulttodoso.Duringtheprintingprocess,thelaserprintergoesthroughseveralprocessesofcharging,scanning,imaging,andtransfer.Duetopotentialmigration,tonertransfer,plustheinfluenceofthelightconductor"lightdecay"?Thetonerimage"cannotbecompletelytransferredtoOntheprintingpaper,theamountoftonerremainingonthesurfaceofthephotosensitivedrumdirectlyaffectsthequalityoftheprint.
Iftheresidualtoneronthesurfaceofthephotosensitivedrumcannotbecompletelyremoved,itwillbeInthenextprintingcycle,thenewlygenerated"tonerimage"willbedestroyed.Therefore,thesurfaceofthephotosensitivedrummustbethoroughlycleaned,whichrequiresaphotosensitivedrumcleaner.Therearetwocleaningmethodsforlaserprinters:rubberscrapercleaningandBrushcleaning.Theirroleistocleanthesurfaceofthephotosensitivedrum.
(1) Kaavinpuhdistus
Therubbercleaningbladeismadeofurearesinandhasaflatsurface.Thebladeisstraightandhasabrasionresistanceandflexibility.Thebladeformsashearanglewiththesurfaceofthephotosensitivedrumandhasacertainpressure.Whenthephotosensitivedrumrotateswiththetonerremainingonthesurface,theremainingtonerisscrapedintobythecleaningbladeInthewastetonercollectionbin.Thereisanon-returnsheetatthepositionoppositetothescrapertopreventthewastetonerfromflyingoutaftercleaning.Becausetherubberscraperisalwaysshearedwiththephotosensitivedrumandhasacertainpressure,itwillcausethesurfaceofthephotosensitivedrumIfthebladeofthecleaningbladeisdamaged,thetonerremainingonthesurfaceofthephotosensitivedrumcannotbecompletelyremoved,causingtheimagesinthenextprintingcycletooverlapandproducepoorprintingresults.
(2)Harjojen puhdistus
Brushcleaningistousearotatingrollerbrushtocleantheresidualtoneronthesurfaceofthephotosensitivedrum,toremovetheresidualtonerandshakeFallingintothewastetonercollectionbin.Thebrushisgenerallymadeofman-madefibersandrubswiththephotosensitivedrumwhenrotatingtoremovetheresidualtoner.Atthesametime,thestaticelectricitygeneratedbythefrictionisusedtoabsorbtheresidualtoner,sothatthetonerwillnotflyandpolluteotherpartsoftheprinter.Themethodofusingabrushtocleanthesurfaceofthephotosensitivedrumcanprolongtheservicelifeofthephotosensitivedrum.
(3)Jätevärien keräysastia
ThewastetonercollectionbinisRecyclingandcleaningtheresidualtonerdevice.Thecollectedtonerisgenerallynolongerused.Becausetherearemanyimpuritiesinthecollectedtoner,whichwillaffecttheprintingquality,someprintersuserecycledtoner.Thescrapedtonerissentbacktothetonersupplybinbyascrewfeedingdeviceforrecycling.However,afteraperiodofuse,thereplenishmentofnewtonerisinsufficientortheoldandnewtonercannotbefullymixed,andtheprintqualitywilldropalot.
Mechanicaltransmission
Theelectroniccontrolsystemcontrolsthemechanicaldevicetocompletethetransmissionofthepaperduringtheprintingprocess.Itincludesthetransmissiongear,thephotoelectricsensor'sblockingleverandthepickupwheel.Mechanical.Thetransmissionsystemhasdifferentstructureduetodifferentmodels,buttheworkingprincipleisbasicallythesame.Themechanicalstructureofhigh-endmodelsismorecomplicated.Forexample,thereisgenerallyno"printpaperalignment"deviceformid-rangeandlowermodels,andhigh-endmodelshavethisdevice.Therearealso"paper-inreel"and"paper-outreel".MultiplewindingdevicesSetting,canmakethetransferofprintingpapermorestable,andalsoreducethephenomenonof"paperjam".Themechanicaltransmissionsystemismainlygeartransmissionbetweenvariouscomponents,whichisrelativelyintuitive.Letmetalkabouthowthemechanicaltransmissionactionoftheelectromechanicaldeviceiscompleted.
(1)Imusähkömagneettinen kytkin
ThepaperfeedingdeviceofHPseriesprintersadoptstheattractionelectromagneticclutchtocontrolthestopandrotationofthepaperfeedingcamtocompletepapertransportation.Whentheelectromagnetreceivesthesignalvoltageofthecontrolcircuit,currentflowsthroughtheelectromagnetcoil,generatinganelectromagneticfieldtoattractthearmature,thecamisreleased,andthetransmissiongeardrivesthepickuprollertorotatetogether.Thereisarubberlayeronthepickuprollersurface,whichfollowsthepickuproller.Rotate,thefrontedgeofthecamdrivesapieceofprintingpaperintotheprintingchannel.
(2) Kitkasähkömagneettinen kytkin
ThepaperfeedingdeviceofHP,Canon,Epsonandotherseriesofhigh-endprintersusesfrictionelectromagneticclutchtodirectlydrivethepickuproller,Thepaperisfedbythealignmentroller.Itsworkingprincipleis:whenthecurrentsignalflowsthroughtheinternalcoiloftheelectromagneticclutchtogenerateanelectricfield,thelinkageforkinthemiddleoftheclutchispushedtooneendofthecoupling,andthetwofrictionplatesproducefrictionstop,andthepick-upwheelisdrivenbytheshiftforktorotateandprintThepaperisfedintothefrontedgeofthe"paperregistrationroller"insidetheprinterandtheprintingpaperisslightlybowed,andtheprintingpaperisalignedwiththeregistrationroller.Atthistime,theregistrationrollerdoesnotrotate.Whentheregistrationrollerclutchreceivesacommandtorotate,itwillfeedtheprintingpaperintotheprintingpath(thepickuprollerofthefrictiontypeelectromagneticclutchiscircularratherthancam-shaped).
(3)Anturi
Thephotoelectricsensorconsistsofalight-emittingdiodeandaphotodioderespectivelyinstalledintwosmallsealedboxes.Intherelativepositionofthetwodiodes,eachhasasensingwindow.Usuallythereisalevershieldbetweenthetwowindowstoshieldthelightbeamofthelight-emittingdiode.Thephotodiodeisnotexposedtolight,soitcannotbeturnedon,andthelogiccircuitdoesnotwork.Whenthemovingprintingpaperknockstheshutterleverinthemiddleofthephotoelectricsensoropen,thelightbeamofthelight-emittingdiodeisdirectedtothephotodiode,andthephotodiodeisturnedonbythelight,andinformsthelogiccontrolcircuittoissueinstructionstocontroltheprinter'snextperiodofwork.Thepapersensor,paperfeedsensor,andpaperoutputsensoroflaserprintersallusephotoelectricsensors.Itisthelogiccontroldeviceofthemaincontrolcircuit,whichisusedtorealizethetimingcontroloftheprintingwork.Iftherequiredactionisnotsensedwithinthespecifiedperiodofprintingwork,thelogiccircuitwillimmediatelysenda"stop"messagetothemaincontrolcircuittostoptheprinter,andthedisplaypanelwillalsodisplayan"error"message.WaitCheckorrepair.
Electroniccontrol
Theoperationofalldevicesofthelaserprinterisrealizedbyacontrolsystem,whichiscalledthe"electroniccontrolsystem".Thecontrolsystemofdifferentmodelsisdifferent,buttheworkingprincipleisbasicallythesame.Theelectroniccontrolsystemmainlyconsistsofthefollowingparts.
(1)Virtalähdepiiri
Providecontrolvoltageforeachpartoftheprinter.Thepowersupplycircuitisrectified,filtered,andtransformedby220Valternatingcurrenttoprovide24V,5Vdirectcurrentworkingvoltageforthelaserprinter.
(2)Liitäntäpiiri
Establishcommunicationbetweenthecomputerandtheprinter.Receivecomputerdatainformationandconvertitintoprinterlanguagetoprovideprintingdatatothemaincontrolcircuitoftheprinter.Theinterfacecircuitincludesamicroprocessor(CPU).Memory(RAM/ROM).
(3)Pääohjauspiiri
Themaincontrolcircuitisthedatareceivedbytheinterfacecircuitandcontrolsthevariousdevicesoftheprintertoworktogetherinacommandmodetocompletetheprintingprocess.
(4)Skannausohjainpiiri
Thereceivedcomputerinformationisgeneratedbyahigh-frequencyoscillatortogeneratealaserbeam,andthescanningmotoriscontrolledtorotateatauniformspeedtodrivethescanningmirrortocompletethephotoreceptordrumScanandexposetoformanelectrostaticlatentimage.
(5)Päämoottorin ohjauspiiri
Accordingtothecommandissuedbythemaincontrolcircuit,themainmotorisdriventorotate,andthroughthegeartransmissiondevice,poweristransmittedtoeachpartoftheoperation.
(6)Korkeajännitteinen siirtopiiri
Thiscircuitconvertsthelow-voltagepowerprovidedbythepowersupplycircuitintoahighvoltagethroughatransformertoprovidethephotosensitivedrumchargingandtransferrollertransferneeds.
Vianetsintä
One.Outputafullsheetof blackpaper
Mahdollinen epäonnistumisen syy:p>
(1)Jos laser on ehdottomasti hyvä, latauselektrodi saattaa olla oikosuljettu verkkoon;
(2)Skanneripiirin logiikka on väärä;
(3)Väriainekasettiyksikkö purkautuu huonosti;
(4)Signaaliliitäntää ei ole kytketty oikein.
Two.outputfull-frameverticalmusta vyö(viiva)
Mahdollinen epäonnistumisen syy:
(1)Thephotosensitivedrumscraperisdamagedorthesharpobjectonthescraperscratchesthephotosensitivedrum;
(2)Magneettirullakaapimen osittainen vaurio;
(3)Tulostin (yleinen paperipolku) on väriaineen likaantunut.
Kolme.Lähdöshorisontaalinen epäsäännöllinen musta vyö(viiva)
Mahdollinen epäonnistumisen syy:
(1)Valoreseptorin rummunpoistoelektrodikontakti on huono;
(2)Valovastaanottimen rumpujen kaavinleikkausvoiman suurikokoinen;
(3)Valovastaanottimen rumpuvärähtelee, kun virtaa;
(4)Valoherkkä rumpu on viallinen tai asennettu väärin.
4.Täytä koko paperiarkki
Mahdollinen epäonnistumisen syy:
(1) VaaleanpunainenEi ole laatikossa;
(2)Laserin mekaaninen suljin ei ole auki;
(3)Lasersäteen ilmaisin on saastunut tai vaurioitunut;
(4)Laser vaurioitunut.
5.Tulostuspystysuora, säännöllinen leukorrea (palkki)
Mahdollinen epäonnistumisen syy:
(1)Sävy saattaa olla loppu, eikä magneettirullan osassa (yleensä näytteen keskiosassa);
(2)Säteen heijastin on lian saastuttama, kuten kiviaines;
(3) Vieraat objektit ovat estäneet skannausvalopolun.
6.Tulostusvaaka-epäsäännölliset valkoiset palkit (kaista)
Mahdollinen epäonnistumisen syy:
(1)Thechargingelectrodewireiscontaminatedorthecontactofthechargingrollerispoor;
(2)valoherkän rummun pinnalla oleva valoa johtava kerros väsynyt;
(3)Valoherkkä rumpu on heikosti purkautunut.
7.Tulostekuva ja -teksti ovat vaaleita
Mahdollinen epäonnistumisen syy:
(1)PainopaperiKosteus;
(2)Värikaste kostuu valoherkkään rummun komponentti on viallinen;
(3)Valoherkkä rumpupurkautuu huonosti valotuksen jälkeen japintapotentiaali on pieni;
(4)Alivalotus;
(5)Magneettirullan esijännite on alhainen;
(6)Siirtojännite on alhainen.
8.Tuloskuva on väärä
Mahdollinen epäonnistumisen syy:
(1)Älä käytä tavallista painopaperia;
(2)Väriaineen malli ei vastaa koneen mallia tai väriainekosteutta;
(3)valoherkkä kosteus;
(4)Skannauskokoonpanossa on löysiä osia;
(5)Skannausmoottori ei toimi sujuvasti ja värinää esiintyy.
9.Tulostusnäytteellä on harmaa tausta
Mahdollinen epäonnistumisen syy:
(1)KehitysBiasvoltageistooolow;
(2)Magneettisen rullanterän häiriö;
(3)Thedistancebetweenthedevelopingmagneticrollerandthephotosensitivedrumistooclose;
10.Esimerkkikuvien vasen ja oikea puoli on erivärisiä
Mahdollinen epäonnistumisen syy:
(1)Väriaine loppuu;
(2)lataussähköjohdon tai lataustelan saastuminen;
(3)Siirtoelektrodin johdon tai siirtotelan kontaminaatio;
(4)PeilipinnoitusOsittain putoaa.
11.Ylempi ja alempi syvyys näkyvät näytekuvana ja tekstinä
Mahdollinen epäonnistumisen syy:
(1)Siirtoelektrodin johto on likainen;
(2)Väriaineen malli ei vastaa.
12.Tulostettujen esimerkkikuvien ja tekstien sävyt ovat säännöllisiä ylhäältä alas
Mahdollinen epäonnistumisen syy:
(1)valoherkän rummun osittainen väsyminen;
(2)Huono kontakti lataus- ja siirtotelanelektrodien välillä.
13. Vedosten pituussuunnassa esiintyy säännöllisiä valkoisia täpliä
Mahdollinen epäonnistumisen syy:
(1)Osittaista värjäystä valoherkässä rummussa;
(2)latausrullan osittainen vaurioituminen;
(3)Kiinnitystelan pinnan osittainen vaurioituminen.
14. Vedosten pituussuunnassa on säännöllisiä mustia täpliä (pisteitä)
Mahdollinen epäonnistumisen syy:
(1)Thephotoconductoronthesurfaceofthephotosensitivedrumisbrokendownortherearespots;
(2)Latausrullan ionisaatiokalvo vaurioitunut;
(3)Kiinnitysrullan pinnalla on fluorikalvoa. Vahinko (vika on hieman vaaleampi).
15.Epäsäännöllisiä mustia täpliä näkyy todisteista
Mahdollinen epäonnistumisen syy:
(1)Väriaineessa on epäpuhtauksia;
(2)Värikasettikokoonpanon jäteväriaineen valkoinen palautuslehti on muotoutunut tai vaurioitunut;
(3)Väriaineen vuotaa.
Kuusitoista.Epäsäännölliset mustat viivat näkyvät sivulla pystysuoraan tai vaakasuoraan
Mahdollinen epäonnistumisen syy:
(1)valoherkän rummun pinnalla oleva valoa johtava kerros naarmuuntunut;
(2)Kiinnitystelan pinta naarmuuntunut;
(3)Valoherkkä rummi värisee käynnissä.
Seitsemäntoista.Tuloksena näytekuvat ja tekstit ovat säännöllisiä eri sävyjä ylhäältä alas
Mahdollinen epäonnistumisen syy:
(1)valoherkän rummun osittainen väsyminen;
(2)Huono kontakti lataus- ja siirtotelanelektrodien välillä.
18. Vedosten pituussuunnassa esiintyy säännöllisiä valkoisia pisteitä
Mahdollinen epäonnistumisen syy:
(1)Osittaista värjäystä valoherkässä rummussa;
(2)latausrullan osittainen vaurioituminen;
(3)Kiinnitystelan pinnan osittainen vaurioituminen.
19. Vedosten pituussuunnassa on säännöllisiä mustia pilkkuja (pisteitä)
Mahdollinen epäonnistumisen syy:
(1)Thephotoconductoronthesurfaceofthephotosensitivedrumisbrokendownortherearespots;
(2)Latausrullan ionisaatiokalvo vaurioitunut;
(3)Kiinnitysrullan pinnalla on fluorikalvoa. Vahinko (vika on hieman vaaleampi).
20.Sivun kuvatiedot puuttuvat
Mahdollinen epäonnistumisen syy:
(1)KuvaResoluutioasetus ei ole tarpeeksi suuri;
(2) Ohjaimen määrittämä tulostustila on virheellinen;
(3)Kuvien koko ja tulostussivu on asetettu väärin;
(4)Tiedonlähetysvirhe.
Twenty-one.Pagevertical-merkkipakkaus
Mahdollinen epäonnistumisen syy:
(1)valoherkän rummun vaihteisto on löysällä;
(2)Vaihteiston suhde ei ole oikea;
(3)Päämoottorin nopeudensäätö epäonnistuu.
Kaksikymmentäkaksi.Sivun kuvan vaakasuora kohdistusvirhe
Mahdollinen epäonnistumisen syy:
(1)Sivutulosteen sisältö on liian monimutkainen ja tulostimen muisti ei riitä;
(2)Sivukoko ylittää tulostimen määrittämän koon.
Kaksikymmentäkolme.Sivun merkit vääristyvät ja vääristyvät
Mahdollinen epäonnistumisen syy:
(1)Valoherkkä rumpusäiliön patruunakokoonpano liikkuu aksiaalisesti;
(2)Skannauskokoonpanon linssit ovat löysällä;
(3)Huono sähköpurkaus ennen kiinnitystä;
(4)Skannauksenohjauspiirin kidekillaattori on vaurioitunut.
Kaksikymmentäneljä. Painopaperin takana oleva kontaminaatio
Mahdollinen epäonnistumisen syy:
(1)Tulostimen paperipolku on väriaineen saastuttama;
(2)Kiinnityskokoonpanon painekumitela on saastunut.
Kaksikymmentäviisi.Painetut merkit ovat onttoja
Mahdollinen epäonnistumisen syy:
(1)Käytetty painomateriaali ei täytä vaatimuksia;
(2) Väriainemalli on väärä
(3)Kiinnitystelan lämpötila on liian korkea.
26.Sivun merkkejä ei ole kiinnitetty tiukasti, ja pinta on karkea
Mahdollinen epäonnistumisen syy:
(1)Kiinnityslämpötila on alhainen;
(2)Kiinnityskumirullan paine on riittämätön;
(3)Käytetty väriaine ei vastaa mallia.
27.Verkkosivun vasemmalla tai oikealla merkit puuttuvat
Mahdollinen epäonnistumisen syy:
(1)Valonpolku on estetty;
(2)Keraamistettu malli,kiinnityskansi on vaurioitunut ja siirtynyt.
Kaksikymmentäkahdeksan.Kaksi kaksoiskuvaa näkyy sivun pystysuunnassa
Mahdollinen epäonnistumisen syy:
(1)Valoherkät rummunpuhdistusterät;
(2)Thesurfacetemperatureoftheheatrolleristooloworthepressureoftherubberrollerisinsufficient;
(3)ThefluorinefilmonthesurfaceoftheheatrolleriswornandthesurfaceTonermeltthatadheresalot.
29.Epäsäännöllisiä mustia viivoja sivulla pystysuoraan tai vaakasuoraan
Mahdollinen virheen syy:
(1)valoherkän rummun pinnalla oleva valoa johtava kerros naarmuuntunut;
(2)Kiinnitystelan pinta naarmuuntunut;
(3)Valoherkkä rummi värisee käynnissä.
30.Epäsäännöllisiä mustia täpliä näkyy todisteina
Mahdollinen epäonnistumisen syy:
(1)Väriaineessa on epäpuhtauksia;
(2) Rumpukokoonpanon sisällä olevan jäteväriaineen valkoinen palautuslehti on vääntynyt tai vaurioitunut;
(3)Väriaineen vuotaa.
Developmentprospects
ThelaserprinterwasinventedbyXeroxinthelate1960s,usingelectro-photo-graphytechnology.Thistechnologyusesalaserbeamtoscantheopticaldrum,andbycontrollingtheonandoffofthelaserbeamtomakethesensordrumabsorbornotabsorbthetoner,theopticaldrumtransferstheabsorbedtonertothepapertoformaprintingresult.Theentireprintingprocessofalaserprintercanbedividedintothecontrollerprocessingstage,inkshadowandtransferstage.Thelaserprinterwasinventedveryearly,buttherealpopularizationandpromotionbeganintheearly1980s,andthedevelopmenttrendhasbeenacceleratedinthepasttwoyears.Thedevelopmentoflaserprintersincludesthefollowingaspects.
(1)Hinta on laskenutmerkittävästi
Theoriginallaserprinterwasaluxuryproduct,andmostpeoplecouldnotreachit.Intheearly1980s,Canoncommercializeddesktoplaserprintersandformedtheminbatches.Thepricedroppedsharply.Asaresult,laserprintersgraduallybegantobepromoted.Theirpopularityandpromotioninturnpromotedthedeclineinprices,andtheirdevelopmentspeedwasrapid.,Israreincomputersandperipheralproducts.Inearly1997,Hewlett-Packardtooktheleadinfurtherreducingthepricesofmostofitslaserprinters,andothercompaniesalsoloweredtheirprices,bringingthepriceofordinarylaserprinterstonearly3,000yuanperunit.In2003,abatchofthousand-yuanlaserprintersledbyHPappeared.
(2)Liikkeen suorituskyky on parantunut huomattavasti
Asakeycomponentofthelaserprinter,themovementincludestheintegrationofmachinery,optoelectronicsandothertechnologies.Technologicalprogresshaspromotedtheimprovementofmovementperformance.Twoyearsago,thepopularlaserprintercoresweregenerally600dpi,andthecoresweregenerally240,000dpiorevenhigher;thespeedalsodevelopedfrom4ppm,8ppmto16ppm,24ppm;theformatisnotonlyA4,butalsoB4,A3format..
(3)Ohjausteknologiasta on tulossa entistä täydellisempi
Thecontrolleristhesoulofthelaserprinter,itdirectlyaffectstheperformanceoftheprinter,andtheprocessingusedbythecontrollerisnowTheprocessor(CPU)hasevolvedfromasingleMotorola68000toaRISCchip,suchasIntel’si960andAMD’s29000,anditsprocessingcapabilitieshavebeengreatlyenhanced;secondly,thelaserprinterpagedescriptionlanguage(PDL)hasbecomeanindustrystandard,andPostScripthasbecomeahigh-endlaserprinterThestandardlanguageofHPPCL;HPPCLlanguagehasbecomethedefactostandardformiddleandlow-endlaserprinters.Laserprinterseitherhaveemulationsinoneoftheselanguagesorboth;again,newtechnologiessuchasresolutionenhancementtechnology(RET,alsoknownassmoothingtechnology)andmemoryenhancementtechnology(MET,alsoknownasmemorycompressiontechnology)continueAppeared,andismasteredbymoreandmoremanufacturers.
Theindustryhasbeenarguingwhetherthefuturedevelopmentprospectsarelaserstoreplaceinkjets,orwhetherthetwowillleadtheway.Butitissuchatopicthatisnolongernew,afterthefirstquarterof2006,itonceagainbecamethecenterofpeople'sdiscussion.Thepurelytheoreticaldiscussionand"teaching"maybetooemptyandabstract.Therefore,wemightaswellcomparethetwofromtheseveralelementsthatmustemergefromtheprintingrequirements,intermsofcostinvestment,printingqualityandspeed,printingloadandstabilityInthesethreeaspectsthatconsumersaremostconcernedabout,acomprehensivecomparisonismadebetweenLaserandPenta.
Features
Thetechnicalstructureoflaserprintingismuchmorecomplicatedthanthatofinkjet,whichinvisiblyincreasesthecostoftheproduct.Therefore,inkjetoccupiesaclearadvantageintheinitialinvestment,entry-levelInkjetprintingonlycostsafewhundredyuan,andsomeproductsareevenlower,whileblackandwhitelaserprintingishoveringatthethresholdofonethousandyuan.Therefore,thereisalsoaviewthatthelaserhittingthatrequiresrelativelyhighupfrontinvestmentcannotbecomparedtothecheapandhigh-qualityjethitting.Infact,thisviewignoresaverykeyhiddenfactor,thatis,sprayingisnotalwayssuchalowprice,anditsproductshavegonethroughalongprocesslikebeingpopularizedandapplied.Ontheotherhand,thepriceofLaserisdroppingstepbystep.WhetheritcanbereducedtothesamepriceasPentaisunknown,butitwillbeamatteroftimebeforeitbreaksthroughthepsychologicalpriceofconsumers.Thepriceofabout1,000yuanisactuallynothighforbusinessapplications.Therearemanyexamplesofsuccessfulproductsonthemarket,suchastheSamsungML-1610,whichisknownasthe"KingofShortShots",andthesmallestandlightestblackandwhitelaserall-in-onemachine.SamsungSCX-4200,thehotsalesofthesetwoproductsfullyshowthatthepricethresholdoflaserhittingisnotasinsurmountableasimagined.
Anotheraspectthatdeterminesthecostisthelaterstageinvestmentoftheproduct,especiallythelaterstageconsumablesinvestment.Behindthecommonpricecutsandfiresales,themeaningoftheproductitselfhasbeenweakenedtoacertainextent,andtheinputofconsumableshasbecomethemostcriticalfactoraffectingTCO.Generallyspeaking,theoriginalinkcartridgesusedininkjetprintersarepricedataboutoneortwohundredyuan,andcanprintfourtofivehundredordinaryA4textfiles,ignoringthecostofpaper,andtheaverageprintingcostperpageisabout0.2to0.5yuan.Thepriceofatonercartridgeforlaserprintersisabout500yuan(blackandwhite).Regardlessofthelossofthetonercartridge(thelifeofthetonercartridgeisusuallyverylonganditisnotallowedtobeincludedintheconsumablesundertheconditionofnotverystrict),itsconvertedprintingcostisnotTo0.1yuan.Inthisway,ifyouprintalargenumberofdocuments,youcansavemoneyforafewprintersinamonth,andtheadvantageoflaserprintersintheoverallcostinvestmentisimmediatelyapparent.
Verrattunapistematriisitulostimiin ja mustesuihkutulostimiin lasertulostimilla on ilmeisiä etuja.
(1) Korkeus. Lasertulostimien pienin tulostustarkkuus on 300 dpi, ja niissä on korkeita resoluutioita, kuten 400 dpi, 600 dpi, 800 dpi, 1200 dpi, 2400 dpi ja 4800 dpi.
(2)Nopea. Lasertulostimien vähimmäistulostusnopeus on 4 sivua minuutissa, yleensä 12 sivua minuutissa, 16 sivua minuutissa, ja joidenkin lasertulostimien tulostusnopeus voi olla yli 24 sivua minuutissa.
(3)Vähäinen.Yleensä alle 53dB,soveltuuerittäin hiljaisiin toimistotiloihin.
(4)Strongprocessingcapability.Thelaserprinter'scontrollerhasaCPUandmemory.Thecontrollerisequivalenttothecomputer'smotherboard,soitcanperformcomplexwordprocessing,imageprocessing,andgraphicsprocessing,whichcannotbedonebydotmatrixprintersandinkjetprinters.Thedifferencebetweenapageprinterandalineprinter.