Illumination system and projection apparatus

A projection apparatus, comprising an illumination system, a light valve, and a projection lens, wherein the illumination system is configured to provide an illumination light beam, the light valve is disposed on a transmission path of the illumination light beam to convert the illumination light beam into an image light beam, and the projection lens is disposed on a transmission path of the image light beam to project the image light beam out of the projection apparatus;

• and the illumination system comprises a light source module, a phosphor wheel, a light recycling element, and a light uniformizing element, wherein:
• the light source module is configured to emit an excitation light beam;
• the phosphor wheel comprises a phosphor region;
• at a first timing, the excitation light beam is transmitted to the light uniformizing element, so that the illumination system outputs first light in the illumination light beam;
• at a second timing, the excitation light beam is transmitted to the phosphor region of the phosphor wheel, so that a part of the excitation light beam transmitted to the phosphor region is converted into a first converted light beam, and the other part of the excitation light beam transmitted to the phosphor region forms an unconverted light beam and is transmitted to the light recycling element, and is reflected by the light recycling element to form a recycled light beam, the recycled light beam is transmitted to the phosphor region of the phosphor wheel, and a part of the recycled light beam is converted into a second converted light beam, wherein the first converted light beam and the second converted light beam are transmitted to the light uniformizing element through a same path, so that the illumination system outputs second light in the illumination light beam;
• and
• at the second timing, reflectivity of the light recycling element to a waveband of the excitation light beam is greater than 90%.