Wavelength conversion element, method of manufacturing wavelength conversion element, light source device, and projector

A method of manufacturing a wavelength conversion element, the method comprising:

• a preparation step of preparing a wavelength conversion layer that has a plurality of pores, a first surface, and a recess formed at the first surface and that is excited by light in a first wavelength band to generate light in a second wavelength band different from the light in the first wavelength band;
• a first step of forming a first bonding layer at the first surface of the wavelength conversion layer;
• a second step of forming a reflection member at a second surface of a substrate;
• a third step of forming a second bonding layer at the reflection member;
• a fourth step of applying energy to the first bonding layer and the second bonding layer;
• a fifth step of pressing the first bonding layer and the second bonding layer, and bonding the first bonding layer and the second bonding layer so that the recess is covered by the second bonding layer;
• and
• a sixth step of separating the reflection member and the substrate, wherein
• in the first step, a part of the first bonding layer is formed in the recess.