Wavelength conversion member and method for manufacturing the same, light-emitting device, and projector

A wavelength conversion member comprising

• a substrate;
• and
• a wavelength conversion layer containing a binder and a phosphor, and disposed on the substrate,
• wherein in a cross section orthogonal to an arrangement surface of the wavelength conversion layer on the substrate, a ratio of a sum of a particle cross-sectional area of the phosphor to a cross-sectional area of the wavelength conversion layer is in a range of 56% to 70%, and
• wherein an average thickness of the wavelength conversion layer is in a range of 55 μm to 146 μm.

A method for manufacturing a wavelength conversion member, the method comprising:

• applying a phosphor composition onto a substrate, wherein
• the phosphor composition comprises a binder, a solvent, and a phosphor,
• a boiling point of the solvent is in a range of 200° C. to 300° C.,
• a mass ratio of the solvent to the binder is in a range of 0.01 to 0.4, and
• a mass ratio of the phosphor to the binder is in a range of 3.15 to 6.05;
• and
• heat-treating the phosphor composition applied onto the substrate to form a wavelength conversion layer.