"to bend or break the natural course of" (light, sound, heat, etc.), 1610s, back-formation from refraction, and in part from Latin refractus, past participle of refringere "to break up," from re- "back" (see re-) + combining form of frangere "to break" (from PIE root *bhreg- "to break"). Related: Refracted; refracting.
<a href="https://www.etymonline.com/word/refractor">Etymology of refractor by etymonline</a>
Harper, D. (n.d.). Etymology of refractor. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/refractor