Magnifiers yog ib qho yooj yim pom optics siv los soj ntsuam cov ntsiab lus me me ntawm ib qho khoom, thiab yog converging lo ntsiab muag nrog ib tug ntau me me focal ntev tshaj qhov photopic deb ntawm lub qhov muag. Qhov loj ntawm ib yam khoom uas pom ntawm retina ntawm tib neeg lub qhov muag yog proportional rau lub kaum sab xis (saib lub kaum sab xis) ntawm cov khoom rau lub qhov muag.
Magnifying iav tseem hu ua daim iav hluav taws. Cov cuab yeej kho qhov muag yooj yim uas tuaj yeem tau txais cov duab zoo nkauj virtual. Nws feem ntau muaj lub lens convex thiab ib lub thav duab thiab kov. Thaum siv, los ntawm kev tso cov khoom nyob ze tom qab lub lens (hauv qhov ntev focal), koj tuaj yeem pom cov duab virtual ntawm upright magnification, uas pab kom paub qhov txawv cov ntsiab lus, thiab feem ntau yog siv los saib cov qauv, kos duab, tsis zoo, duab, luam yeeb yaj kiab. , thiab lwm yam raws li qhov curvature thiab qhov refractive index ntawm iav siv, muaj ntau hom magnification, xws li 10, 20, 30 zaug.