名詞 collimator:

1. a small telescope attached to a large telescope to use in setting the line of the larger one
2. optical device consisting of a tube containing a convex achromatic lens at one end and a slit at the other with the slit at the focus of the lens; light rays leave the slit as a parallel beam

col.li.ma.tor

n.（名詞）
A device capable of collimating radiation, as a long narrow tube in which strongly absorbing or reflecting walls permit only radiation traveling parallel to the tube axis to traverse the entire length.
準直儀，平行光管：一種能使射線成平行狀的儀器，如一個狹長試管的強烈吸收或反射的內(nèi)壁，使得射線只有在和試管軸線相平行時才能穿過整個試管