Abstract: A therapeutic method of using a lamp comprised of a fixture for retaining a light bulb in a position to be viewed by the eyes of a patient, apparatus for restricting the wavelengths of light emitted by the light bulb to those between 490 and 520 nanometers, and apparatus for restricting the light energy irradiance to between about 1.8 and 200 microwatts per square centimeter over at least the eyes of the patient. The restricting apparatus can be a narrowband light transmission filter or the phosphor of a fluorescent bulb. By the use of this lamp, the effects of seasonal affective disorder (SAD) or other chronobiological disorders are reduced or eliminated without substantially encountering the side effects of hypomania, irritability, nausea or agitation previously found.

Abstract: A method of avoiding the influence of light on the biological clock caused by the presence of full spectrum light during intervals unexpected by the human body is comprised of wearing goggles that substantially block light having wavelengths of between about 480 and 530 nm. during exposure to the light, while conducting normal activities using visible light of other wavelengths.