Zhè tái zhéshè wàngyuǎnjìng de kǒujìng shì shí límǐ.
This refracting telescope has an aperture of 10 cm.
Tips
usage
Contrast with 反射望远镜 (reflecting telescope) and 折反射望远镜 (catadioptric). Refractors use lenses, reflectors use mirrors - beginner astronomy textbooks always introduce them as a pair.
