Abstract: This paper analyzes ray paths of the dual-channel projection system and introduces the design of the projection collimator optics. The projection system consists of a target source generator and an inference source generator sharing the same optics. The optics uses a re-imaging configuration to meet the packaging requirement. The beam splitter is located between the last surface and the focal plane of the optics to combine the target source channel. By reducing the thickness of the beam splitter, the aberration of the optics in the inference source channel is reduced. The optics collimates the output from an infrared source in the 8 m~12 m waveband and enables an imaging system with 8.5 field of view to be tested. The effective focal length of the optics is 315.69 mm and the entrance pupil relief is 900 mm.The obtained performance shows the optics meet the requirements of the projection system.