Light for Health and a Better Mood

Jens Balasus, one of akaris’ two founders, hands me what looks like a pair of ski goggles. Even though we are sitting in a well-lit office, my eyes need a moment to adjust to the glaring “daylight” inside the mask. A bright sky arches overhead—the sensation is reminiscent of a VR headset. In fact, the sun is only just “rising”: at least that is what the scene inside the goggles imitates. Over time, the display transitions into a clear blue summer sky. “When you’re lying on your back, it’s like being out on a meadow, looking into the distance,” says akaris co-founder Alexander Herzog.

That sense of wellbeing, the two founders explain, has a scientific basis. “At the Chair of Adaptive Lighting Systems and Visual Processing, we also work on the health-related components of light,” they say. Like all living organisms, humans are strongly aligned with a day–night rhythm—reflected in performance curves and our need for sleep at night. The key control mechanism is daylight, which regulates our activity cycle via the body’s own hormones such as melatonin and serotonin, and through a multitude of biochemical processes. “But we spend around 90 percent of our time indoors, where natural light can barely steer our internal clock,” Herzog says.

Daylight as a Health Factor

Even modern indoor lighting systems emit only parts of the sun’s spectrum, the lighting engineers explain. Daylight-like illumination requires not only a combination of many specific wavelengths, but also a defined illuminance—i.e., the luminous flux falling on a surface. For more than seventy years, the Chair of Adaptive Lighting Systems and Visual Processing at TU Darmstadt has researched the interdisciplinary effects of light on human health, including harmful influences such as UV radiation. “You tend to notice the positive effects of light on the body over the long term—and they are used surprisingly little,” Herzog says. The two scientists, who worked at neighboring desks, decided to change that.

The initial idea emerged during a lunch break. “We had LED panels with a production defect that reproduced a natural sky gradient,” they recall. They found the effect aesthetically appealing and strikingly natural—prompting them to think about how it could be applied deliberately. A lack of sufficient daylight in winter is a common issue, yet it is crucial for preventing sleep disorders, fatigue, and the winter blues, and for reducing the effects of shift work and jet lag. Daylight lamps do exist, Balasus notes, but they are often not used at the necessary close distance. Drawing on their LED expertise and their scientific understanding of how light affects humans, the two developed the concept of a “light mask.” “We want to make the positive effects of light easily accessible,” Balasus says. The name akaris is derived from the Japanese akari (明かり), meaning light.

“I always wanted to start a company,” Herzog says. They found inspiration at INNODAY and similar events hosted by HIGHEST. “We want to make our research insights accessible through innovative products.” After all, who knows that dim green light may help with migraines, that red light can support retinal regeneration, or that certain types of light flicker may influence Alzheimer’s? The first version of the mask was still somewhat bulky—but test users were enthusiastic. “Family and friends were immediately convinced—and even HIGHEST’s advisor didn’t want to take the mask off,” Herzog recalls. Fifteen minutes a day—or two sessions of ten minutes—can deliver a tangible energy boost. “Afterwards I’m awake and focused,” Balasus says. Herzog adds: “It can demonstrably optimize performance before competitions as well.”

Relaxation—Like Being on Holiday

The sense of horizon and distance relaxes the eyes. “We simulate sunrise and sunset, all the way to a blue sky,” Balasus explains, describing how the visual presentation changes. Herzog sketches the wavelength distribution of conventional LED lights, which typically show a pronounced gap in the spectrum. “That spectral gap can be a problem for the human circadian clock in winter,” he says. Thanks to their expertise, they can reproduce the visible portion of the daylight spectrum with high precision—without harmful UV radiation or blue-light damage. A follow-up model is more compact and features a more refined design. Since the start of the year, product designer Erika Martinez Duque has been supporting the team. The next target is to produce a modern lifestyle wearable; certification as a medical device would be expensive and time-consuming.