Rau qhov precision, kev ua haujlwm nruj heev, cov txheej txheem ua haujlwm muaj cov cuab yeej hauv, cov cuab yeej tawm, thiab lwm yam.. Rau qhov loj ntawm cov kev xav tau tshwj xeeb, cov kev xav tau precision, xws li 1 hli ntxiv lossis rho tawm pes tsawg microns, thiab lwm yam, yog tias qhov loj me. ntawm qhov tsis ncaj ncees lawm ntau dhau yuav dhau los ua seem, tom qab ntawd qhov sib npaug ntawm qhov yuav tsum tau rov ua dua, siv sijhawm thiab siv zog, thiab qee zaum txawm ua rau tag nrho cov khoom siv seem, uas ua rau cov nqi nce ntxiv, tib lub sijhawm, cov khoom yog yeej tsis muaj.
Rau qhov kev ua tiav qhov kev ua tiav yog qhov tseem ceeb, xws li ntau npaum li cas lub cylindrical txoj kab uas hla, muaj cov kev cai nruj, qhov zoo thiab qhov tsis zoo nyob rau hauv cov kev cai tshwj xeeb kom tsim nyog qhov chaw, txwv tsis pub lawv yog qhov tsis tsim nyog; qhov ntev, qhov dav thiab qhov siab kuj tseem muaj cov kev cai nruj nruj, qhov zoo thiab qhov tsis zoo kuj tau teev tseg, xws li lub tog raj kheej embedded (piv txwv li qhov yooj yim tshaj plaws), yog tias txoj kab uas hla loj dhau, ntau dua qhov kev ua yuam kev, nws yuav tshwm sim los ntawm, ntxig tsis nyob rau hauv qhov teeb meem, yog hais tias qhov tseeb txoj kab uas hla yog me me heev, ntau tshaj li qhov tsawg kawg nkaus txwv ntawm qhov kev ua yuam kev tso cai rau tus nqi tsis zoo, nws yuav ua rau inserted dhau xoob, tsis muaj teeb meem tshwm sim. Cov no yog cov khoom tsis tsim nyog, lossis qhov ntev cylindrical ntev dhau los lossis luv dhau, dhau ntawm qhov kev ua yuam kev, yog cov khoom tsis tsim nyog, yuav tsum tau muab pov tseg, lossis rov ua dua, uas yuav ua rau muaj kev nce nqi ntxiv.
Precision qhov yuav tsum tau ua nyob rau hauv qhov tseeb qhov teeb meem loj loj, yuav tsum nruj me ntsis raws li lwm yam ntxiv drawings rau kev ua, ua tawm ntawm qhov tseeb loj yuav yeej tsis zoo ib yam li qhov theoretical loj ntawm cov duab kos, tsuas yog, ntev li ntev tau. Qhov loj me nyob rau hauv qhov kev ua yuam kev kam rau ua yog qhov tsim nyog, yog li qhov yuav tsum tau ua ntawm precision qhov chaw ua haujlwm yog nruj raws li qhov loj me rau kev ua.
Qhov thib ob yog qhov siab tshaj precision qhov chaw ua cov khoom siv thiab cov khoom siv kuaj, cov cuab yeej ua haujlwm siab heev ua rau kev ua cov khoom ua tau yooj yim dua, siab dua precision, zoo dua. Cov cuab yeej kuaj xyuas tuaj yeem kuaj xyuas qhov tsis ua raws li qhov yuav tsum tau ua, kom tag nrho cov khoom xa tuaj rau cov neeg siv khoom tiag tiag ua tau raws li qhov yuav tsum tau ua.