Wavelength conversion module, method of forming wavelength conversion module, illumination system and projection apparatus

A method of forming a wavelength conversion module, comprising:

• providing a substrate, wherein the substrate comprises an axis located at a center of the substrate;
• forming a reflective layer on the substrate, and the reflective layer having two first reflective regions and a second reflective region, wherein the second reflective region is located between the two first reflective regions in a radial direction from the axis of the substrate to an edge of the substrate, and a distance from a top of the reflective layer in the second reflective region to the substrate is smaller than a distance from a top of the reflective layer in each of the first reflective regions to the substrate;
• and
• forming a wavelength conversion layer on the substrate, wherein the reflective layer is located between the substrate and the wavelength conversion layer.

An illumination system, comprising:

• a wavelength conversion module, comprising:
• a substrate, comprising an axis located at a center of the substrate;
• a reflective layer, located on the substrate, and the reflective layer having two first reflective regions and a second reflective region, wherein the second reflective region is located between the two first reflective regions in a radial direction from the axis of the substrate to an edge of the substrate, and a distance from a top of the reflective layer in the second reflective region to the substrate is smaller than a distance from a top of the reflective layer in each of the first reflective regions to the substrate;
• and
• a wavelength conversion layer, located on the substrate, wherein the reflective layer is located between the substrate and the wavelength conversion layer;
• and
• an excitation light source, configured to emit an excitation beam, wherein the excitation beam is transmitted to the wavelength conversion module and converted into an illumination beam through the wavelength conversion module.

A projection apparatus, comprising:

• an illumination system, comprising:
• a wavelength conversion module, comprising:
• a substrate comprising an axis located at a center of the substrate;
• a reflective layer, located on the substrate, and the reflective layer having two first reflective regions and a second reflective region, wherein the second reflective region is located between the two first reflective regions in a radial direction from the axis of the substrate to an edge of the substrate, and a distance from a top of the reflective layer in the second reflective region to the substrate is smaller than a distance from a top of the reflective layer in each of the first reflective regions to the substrate;
• and
• a wavelength conversion layer, located on the substrate, wherein the reflective layer is located between the substrate and the wavelength conversion layer;
• and
• an excitation light source, configured to emit an excitation beam, wherein the excitation beam is transmitted to the wavelength conversion module and converted into an illumination beam through the wavelength conversion module;
• a light valve, located on a transmitting path of the illumination beam and is configured to convert the illumination beam into an image beam;
• and
• a projection lens, located on a transmitting path of the image beam and is configured to convert the image beam into a projection beam.