Head-mounted devices for photobiomodulation using ambient light conversion

A wearable head-mounted device comprising:

• a headwear structure including a top portion positioned over a scalp of a user;
• and
• at least one optical element disposed on or within the top portion and configured to receive ambient light,
• wherein the at least one optical element is configured to convert at least a portion of the ambient light and re-emit at least one wavelength within a range of 600 nm to 1000 nm, and
• wherein the re-emitted at least one wavelength is delivered to the scalp to provide photobiomodulation (PBM) therapy to hair follicles.

A wearable head-mounted device, comprising:

• a headwear structure including at least one forward or downward extending portion;
• and
• at least one optical element disposed on or within the at least one forward or downward extending portion and configured to receive ambient light,
• wherein the at least one optical element is configured to convert at least a portion of the ambient light and re-emit at least one wavelength within a range of 600 nm to 1000 nm, and
• wherein the re-emitted at least one wavelength is incident upon at least one of a face, jawline, or neck of a user to provide photobiomodulation (PBM) therapy.