Lub hauv paus chiv keeb ntawm lub peev xwm, los yog qhov muag pom, yog qhov nyuaj rau kev txheeb xyuas. Nws tau hais tias tsawg kawg hauv Tebchaws Europe hauv xyoo pua 16th, tau sim kho cov tsom iav ntawm lub pob tw. Nws tau sau tseg tias ua ntej xyoo pua 19th, rab phom twb muaj lub koob yees duab-hom pom cov cuab yeej uas tuaj yeem siv rau kev tsom mus rau qhov teeb meem qis. Scopes tuaj yeem muab faib ua holographic pom, sab hauv liab-ntsuab dot pom, thiab laser pom.