Refractor telescope with a primary that bends (refracts, like a lens) the incoming light, thus where the light passes through the optical system (glass, ...).
(a primary; bends; refracts, like a lens) the incoming light, thus where the light passes through the optical system (glass, ...).)
a primary
bends
refracts, like a lens) the incoming light, thus where the light passes through the optical system (glass, ...).