A projector includes a light source module, a collimating lens, a dichroic mirror and a wavelength conversion module. The light source module is configured to provide an illumination beam. The collimating lens is configured to collimate the illumination beam. The collimating lens includes a first part and a second part, and an axle positioned between the first part and the second part. The wavelength conversion module is configured to receive the illumination beam from the first part, and further to generate an excitation beam transmitted toward the first part and the second part. The dichroic mirror is disposed on a position corresponding to the first part. The dichroic mirror is configured to reflect the illumination beam toward the first part and be passed by the excitation beam, or further configured to be passed by the illumination beam and reflect the illumination beam.