Light is the primary stimulus for regulating circadian rhythms, seasonal cycles, and neuroendocrine responses in many species including humans. During the past 20 years, studies have tested the use of light for treating fall and winter depression (Seasonal Affective Disorder or SAD), non-seasonal depression, sleep disorders, menstrual dysfunction, and eating disorders. In addition, investigators are exploring the use of light for reentraining human circadian physiology relative to the challenge of shift work or intercontinental air travel.

The circadian response to light is dependent on the stimulus intensity, wavelength, and time of delivery. A phaseresponse curve (PRC) describes lightinduced shifts in rhythms relative to the circadian phase when the light is given, and PRCs to light share similarities across many species.

This invention involves a light meter system for stimulating or regulating neuroendocrine, circadian, and photoneural systems based upon the discovery of peak sensitivity ranging from 425-505 nm. It exploits this peak wavelength sensitivity for light systems, translucent and transparent materials, and lamps or other light sources with or without filters.

The light metering device is specifically configured to accurately quantify electromagnetic radiation that stimulates or regulates the circadian, photoneural, and neuroendocrine systems of healthy mammals or mammals having a variety of disorders. The meter’s wavelength sensitivity matches the wavelength sensitivity of the photoreceptors such regulation.

NASA is actively seeking licensees to commercialize this technology. Please contact NASA’s Licensing Concierge at This email address is being protected from spambots. You need JavaScript enabled to view it. or call us at 202-358-7432 to initiate licensing discussions.