Research

  A Penn State University study published in Leukos has examined how U.S. museum lighting professionals are actually using modern lighting technologies, especially LEDs, and how they choose lighting based on conservation, appearance, and standards. The study creates a current, practice-based snapshot showing that LED adoption is now widespread, but guidance is still applied unevenly [...]

  Researchers at the University of Edinburgh analyzed whether ultraviolet (UV) exposure in low-sunlight regions is associated with better or worse health outcomes, focusing on deaths from cardiovascular disease, cancer, and skin cancer. Using UK Biobank data from 395,000 white European participants across the UK, they linked individual health and genetic records with estimated UV [...]

  This study used ultra–high-field 7T fMRI to examine how temporal light modulation (TLM) (aka flicker) at different frequencies activates or deactivates brain regions in healthy adults, with a particular focus on whether non-perceptible flicker still drives visual cortex responses. Participants viewed LED stimuli modulated at 50 Hz (clearly perceived as flicker) and at ≥100 [...]

  The field of optogenetics is moving from a research tool toward a potential therapeutic strategy for neurological disease, especially chronic neuropathic pain. Optogenetics works by inserting genes for light-sensitive proteins (opsins) into specific neurons so their activity can be turned up or down with precisely delivered light, more like a targeted dimmer than a [...]

  For the legible version of the above image, click here. It’s worth it. This image was created by Stig Kristiansen, a consultant on light + health in Norway. He painstakingly mapped wavelengths of light to different biological functions. The resulting complexity is the most important takeaway. His LinkedIn post about this mapping can be [...]

  Researchers have developed a new way to make ultra-narrow band, near‑infrared LEDs by “electrically powering” materials that normally do not conduct, using attached organic molecules that act as molecular antennas. The work opens a path to highly precise light sources for deep‑tissue medical imaging, optical communication, and chemical or biological sensing. Core scientific breakthrough [...]

  By Eric Bretschneider, Ph.D. Abstract Wien’s Displacement Law is a simple equation that allows calculation of the peak wavelength for a black body light source as a function of temperature.  However, not all uses of light are based on radiant flux. In particular, photobiology is based on the quantum or photon flux.  In 1939, [...]

By Alexander Willemsen, MSE Based on a paper authored by Eric Bretschneider, Ph.D. The Circadian Stimulus (CS) model is one of the most well-known models for quantifying the circadian impact of lighting. One striking feature that separates the model from other contemporary circadian lighting models is its discontinuous action spectrum. As a consequence, the predicted [...]

  A large-scale study by Flinders University analyzed over 13 million hours of light exposure data from 88,905 people aged 40 and older, revealing that bright light at night significantly increases the risk of heart failure and heart attack. Those exposed to the highest levels of nighttime light (measured in lux) had a 56% greater [...]