A phototherapy device includes an outlet end to be placed in contact with a person's skin, a heat exchanger, an optical structure arranged between the heat exchanger and the outlet end, and a light source arranged between the heat exchanger and the outlet end, and configured to emit light for delivery to the skin through or adjacent the optical structure. The heat exchanger may include a first heat transfer portion thermally coupled to the light source for dissipating heat from the light source, and a second heat transfer portion thermally coupled to the optical structure for dissipating heat from the optical structure. The first and second heat transfer portions of the heat exchanger may be substantially thermally isolated from each other, e.g., partially or completely physically separated from each other.