The invention discloses collimator, radiation-emitting device and check equipment.A kind of collimator, it is connect with the ray emitter of divergent-ray, one wherein in collimator and ray emitter is provided with protruding portion, another setting recess portion in collimator and ray emitter, protruding portion is placed in recess portion so that ray emitter and collimator arrangement close to each other and can connect, ray propagates to collimator in the channel in protruding portion and recess portion from ray emitter.
