Medical Lighting



The Right Light throughout the Day

Our bodies work through the same cycle every day. Our internal clock determines sleeping and waking phases, as well as heartbeats, blood pressure and mood – a circadian rhythm of biological processes controlled and supported by light, as well as hormones, specifically cortisol and melatonin. A lack of light throughout the course of the day can result in chronic fatigue, sleep disorders or depression.

VTL (Visual Timing Light) “controls” smart lighting in the office by working in tandem with the body’s natural endorphins. The Waldmann Net Module facilitates biodynamic, human-centric lighting by controlling color-changing VTL fixtures. This innovative light management system brings the dynamics of natural daylight into the building to extend the emotional and ergonomic benefits of light quality. Biodynamic light (Human Centric Lighting) can provide lasting well-being for employees in offices with insufficient daylight and also during the winter months when there are much fewer sunny days.

Light and its interaction with hormones

Cortisol and melatonin levels of the body during a typical course of the day.


The hormone cortisol is produced in the body in the morning. It stimulates the metabolism and programs the body for day mode. The first morning light suppresses the production of the sleep hormone melatonin. VTL supports the activity of the stress hormone cortisol at the beginning of day by stimulating cold-tone light and high illuminance values.


The levels of cortisol decrease over the course of the day. The goal is to maintain the level of alertness and energy during the midday. hours. For VTL, this means that it continues providing mainly activating cold-tone light and high illuminance values.


In the afternoon, the production of cortisol in the body has already decreased significantly, with the more active phase approaching its end. The production of the sleep hormone is not yet required at this time. VTL supports this transitional period by means of a neutral mixed light. The illuminance is gradually reduced to ease into the nighttime hours.


The melatonin hormone affects energy and reduces activity levels in favor of a night sleep. With biodynamic light during the day, the melatonin level is correspondingly high during the night. The person sleeps well and is rested and productive the next day.  VTL supports the transition to the rest phase through reduced brightness and relaxing warm tone light.

To download the NET Module Spec Sheet click here

To download the VTL Brochure click here

To download the LUM CONNECT Brochure click here

Waldmann VTL Net Module Luminaires