A photo-therapy device emits photo-
therapeutic radiation to treat. living tissue. The device incorporates an array of emitters, the photo emissions of which is dependent on their temperature. Temperature feedback is provided to a
voltage supply that supplies current to the emitters, to regulate the
voltage supply level and the temperature of the emitters. Additionally, the
wavelength of the
radiation is dependent on the temperature of the emitters, so the
wavelength is moved closer to an optimum
wavelength for absorption by the tissue by controlling the temperature of the emitters. Furthermore, the useful life of the emitters is extended by pulsing the emitters on and off by sequentially applying an activation
signal to one group of emitters at a time. Also, the device can operate on a wide range of
voltage input levels since it utilizes a switching
regulator, which can convert a voltage level in the range to the level required to drive the array of emitters. The photo-therapeutic
infrared light may be used to treat
insect bites and to relieve
headaches in human beings. The
infrared light emitters may be incorporated into a
mouthpiece for treating gum tissues.