Abstract
Researchers in Korea have discovered that carefully designed white LEDs can help optimize an individual's circadian rhythm. Ji Hye Oh and co-workers from Kookmin University studied four-package white LEDs, which consist of phosphor-converted red, amber and green LEDs, a blue LED and a long-wavelength dichroic filter. They compared these devices with a variety of traditional forms of lighting, and found that such four-package LED designs yield a high luminous efficacy, excellent color rendering and a tunable circadian effect for regulating the secretion of melatonin. The figures of merit suggest that carefully designed white LEDs could play an important role in creating smart lighting systems that help maintain good health, bring energy savings and provide optimal visualization of colors.
Highlights
Over the decade, the solid-state lighting sources based on white lightemitting diodes (LEDs) has improved to overtake incandescent and fluorescent lighting types because of many advantages such as high brightness, ecofriendliness, long-life time, small size, low power consumption and fast response time.[1,2] For these reasons, the LEDs can be applied indoor and outdoor lightings as well as for signals and in displays
Several recent findings confirm that bright artificial light can be used in a number of therapeutic applications, such as in the treatment of seasonal affective disorder (SAD),[5] certain sleep problems,[6] depression,[7] jet lag,[8] sleep disturbances in those with Parkinson’s disease,[9] the health consequences associated with shift work[10] and the resetting of the human circadian clock.[11]
We demonstrate all attainable figures of merit required for optimizing the circadian rhythm, vision performance and color quality of various RB,MAB,MGB,MB four-package white LEDs as well as commercialized lighting sources and daylight
Summary
The solid-state lighting sources based on white lightemitting diodes (LEDs) has improved to overtake incandescent and fluorescent lighting types because of many advantages such as high brightness, ecofriendliness, long-life time, small size, low power consumption and fast response time.[1,2] For these reasons, the LEDs can be applied indoor and outdoor lightings as well as for signals and in displays. Many bio- and medical-related research groups have reported that the spectral profiles of light emitted by white artificial lighting impacts our circadian physiology, alertness and cognitive performance levels.[3,4] Several recent findings confirm that bright artificial light can be used in a number of therapeutic applications, such as in the treatment of seasonal affective disorder (SAD),[5] certain sleep problems,[6] depression,[7] jet lag,[8] sleep disturbances in those with Parkinson’s disease,[9] the health consequences associated with shift work[10] and the resetting of the human circadian clock.[11] quiet recently, Falchi et al.[12] reported that artificial lighting changes natural processes, interferes with melatonin production and disrupts the circadian rhythm. Exposure to blue light late in the evening and at night may be detrimental to one’s health.[3,13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
