Impact of a single, short morning bright light exposure on tryptophan pathways and visuo- and sensorimotor performance: a crossover study

Optimizations of luminescent materials for white light emitting diodes toward healthy lighting

White light emitting diodes (wLEDs) have been widely used as the green lighting sources. The commercial wLEDs devices are mainly achieved through the combination of blue emission chips and yellow phosphors, which offer advantages of high efficiency and long lifetime. However, the color rendering index (CRI) of traditional wLEDs is low due to the lack of red components. In recent years, with the improvement of the quality of life, a lot of efforts have been paid to improve the performance of wLEDs devices related to CRI, correlated color temperature, light uniformity, luminous flux, etc. In this article, we summarize the recent advances on the optimization of wLEDs toward healthy lighting. Brief introductions on the fundamentals of healthy effect of lighting are presented, followed by discussions of current methods to realize wLEDs devices. Special overviews on strategies for luminescent materials of wLEDs in recent years are presented. The opportunities and challenges in the future development of wLEDs lighting devices are also discussed.

A review of the studies on nonvisual lighting effects in the field of physiological anthropology

Here, we review the history and the trends in the research on the nonvisual effect of light in the field of physiological anthropology. Research on the nonvisual effect of light in the field of physiological anthropology was pioneered by Sato and colleagues in the early 1990s. These authors found that the color temperature of light affected physiological functions in humans. The groundbreaking event with regard to the study of nonvisual effects of light was the discovery of the intrinsically photosensitive retinal ganglion cells in the mammalian retina in the early 2000s. The interest of the physiological anthropology scientific community in the nonvisual effects of light has been increasing since then. A total of 61 papers on nonvisual effects of light were published in the Journal of Physiological Anthropology (including its predecessor journals) until October 2018, 14 papers (1.4/year) in the decade from 1992 to 2001, 45 papers (2.8/year) in the 16 years between 2002 and 2017, and two papers in 2018 (January-October). The number of papers on this topic has been increasing in recent years. We categorized all papers according to light conditions, such as color temperature of light, light intensity, and monochromatic light. Among the 61 papers, 11 papers were related to color temperature, 20 papers were related to light intensity, 18 papers were related to monochromatic light, and 12 papers were classified as others. We provide an overview of these papers and mention future research prospects.