Illumination system and projection apparatus

A projection apparatus, comprising:

• an illumination system, comprising:
• a coherent light source adapted to emit a coherent light beam;
• a first light-combining element disposed on a transmission path of the coherent light beam;
• an optical wavelength conversion module disposed on the transmission path of the coherent light beam transmitted from the first light-combining element, the first light-combining element located between the coherent light source and the optical wavelength conversion module, the optical wavelength conversion module converting the coherent light beam into a first converted light beam and reflecting the first converted light beam back to the first light-combining element, a wavelength the first converted light beam is different from a wavelength of the coherent light beam;
• and
• a first auxiliary light source adapted to emit a first auxiliary light beam, a wavelength of the first auxiliary light beam is different from the wavelength of the coherent light beam, wherein the first auxiliary light beam is transmitted to the first light-combining element along the transmission path of the coherent light beam, and the first light-combining element combines the first auxiliary light beam and the first converted light beam reflected from the optical wavelength conversion module;
• a light valve disposed on a transmission path of an illumination beam from the illumination system to convert the illumination beam into an image light beam, wherein the illumination beam is formed from the first converted light beam and the first auxiliary light beam;
• and
• a projection lens disposed on a transmission path of the image light beam.