A phototherapy device comprises a face mask having a rigid (or semi-rigid) shell contoured to the human face. A flexible array of LEDs is affixed to the inner surface of the mask. A flexible, quantum dot-containing film is situated over the flexible array of LEDs. The quantum dots in the QD-containing film are selected to photo-luminesce at one or more particular wavelengths in response to photoexcitation by the light emitted from the LEDs. The LEDs emit “primary light” and the quantum dots down-convert at least a portion of the primary light to “secondary light.” The flexible, quantum dot-containing film may be interchangeable such that the wavelength(s) of the secondary light may be tailored to various phototherapy treatment regimes.