The light source or optical signal often contains visible and infrared light. The cold/hot reflector can separate visible and infrared light and only collect visible light, alleviating the system temperature rise caused by infrared radiation. The hot and cold mirrors provided by MAP optics are made of high quality heat-resistant borosilicate glass materials. The surface is plated with high quality multilayer dielectric film. The spectral characteristics of thermal reflector are high transmittance in visible band and high reflectivity in near infrared band. The spectral characteristics of cold mirror are high reflectivity in visible band and high transmittance in near infrared band. The use of thermal mirrors can reduce heat with minimal impact on overall system performance.