I te tau 1611, ka tangohia e te tohunga arorangi Tiamana a Kepler e rua nga wahanga o te arotahi lenticular hei whainga me te karu kanohi, kua tino pai ake te whakanui, i muri mai ka kiia e te tangata tenei punaha whatu ko te karu a Kepler.

I te tau 1757, na Du Grand i ako mo te karaehe me te wai whakamuri me te whakamararatanga, i whakapumau i te turanga ariui o te arotahi achromatic, me te whakamahi i te karauna me nga mohiti kowhatu e hanga ana i te arotahi achromatic.Mai i tera wa, ka whakakapi katoa te achromatic Refractor Telescope i te tinana karu whakaata roa.

I te mutunga o te rautau tekau ma iwa, me te pai ake o te hangarau whakangao, ka taea te hanga i te karaehe nui ake o te karu whakahurihuri, katahi ka hangaia he nui te diameter Refractor Telescope climax.Ko tetahi o nga tino kanohi ko Ekes telescope 102 cm te whanui i te tau 1897 me Rick telescope 91 cm te whanui i te tau 1886.

Ko te karu whakaata whakaata nga painga o te roa o te aro, he nui te tauine pereti, he koretake te piko o te ngongo, he pai rawa atu mo te mahi inenga arorangi.Engari i nga wa katoa he toenga o te tae, i te wa ano ki te ultraviolet, he tino kaha te whakauru o te radiation infrared.Ahakoa he uaua te punaha whakaheke karaihe whatu nui, ki te karu whakaata whakaata a Yerkes i hangaia i te tau 1897, kua eke te whakawhanaketanga, i te mea kua kotahi rau tau tenei karekau i puta ake te karu whakaata.