Wavelength conversion element and projector

A projector, comprising a light-emitting unit, a wavelength conversion element, a light valve, and a projection lens, wherein:

• the light-emitting unit is configured to emit an illumination light beam,
• the wavelength conversion element is disposed on a transmission path of the illumination light beam, and the wavelength conversion element comprises a substrate, a wavelength conversion layer, a reflective layer, and a heat conductive layer, wherein:
• the wavelength conversion layer is disposed on the substrate,
• the reflective layer is disposed on the substrate and is located between the substrate and the wavelength conversion layer, and
• the heat conductive layer is disposed on the substrate, wherein at least a portion of the heat conductive layer is located between the substrate and the reflective layer,
• the light valve is disposed on the transmission path of the illumination light beam and is configured 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 and is configured to project the image light beam.