By BizLED Bureau
Jan 26, 2016: Researches on human-centric lighting have proved that light is a very powerful time-cue that can effectively set our body clocks. It has also been proved that if human beings are exposed to wrong light at the wrong time, it can lead to a number of disorders in their systems.
Lighting can be controlled to take care of our visual, biological, and emotional needs?this can be done by changing the direction of light, color temperature, or the illuminance levels. LEDs are a good source of light that easily help to control light in each of these dimensions. A LightingEurope?s study states that by 2020, LEDs will take over 90% of the human-centric lighting space.
?Human-centric lighting solutions can actively support the circadian rhythm of human beings, thus promoting a person?s wellbeing, mood, and health,? says Alfred Wacker, chair of LightingEurope?s Light and Health Working Group.
According to a LightingEurope research, human-centric LED lighting have a number of positive impacts on our body and mind. Right type of lighting allows us to sleep and rest properly, and perform with high productivity when we are awake. Tunable lighting has also been proved to enhance healing and help prevent many chronic diseases.
This important fact?lighting?s impact on our body?has been noted by the LED lighting industry and many manufacturers have come up with and are still coming up with newer and more advanced solutions for healthcare, education and zoological applications.
Positive influence of light
Light with a high spectral blue component activates and increases the capability for performance and concentration. If this blue component in light decreases, the body relaxes and changes over to a calm phase. White/white control offers further positive effects on the human biological rhythm. It can improve motivation, the ability to concentrate, thereby increasing productivity.
Lighting designers need to understand the different effects
In the past, lighting designed focused only on the visual aspects of light, as the main purpose of lighting used to be to enable people to see. The visual aspects of light have a significant effect on our performance. For example, light must be bright enough to facilitate performance of the visual tasks, but if the brightness is too high, it can cause glare. The colour-rendering of the light is also important, especially for the purpose of examining patients.
However, our biological and emotional needs are very different from our visual needs, and when a lighting solution is being designed, the designer needs to take into consideration all these effects of light. Lighting designers should be fully aware of these effects and have proper guidelines to go ahead. They should also be aware of the misinformation about lightings effects on our physical and mental health.
Metrics to study effects of light
There are different metrics that can help a lighting designer to distinguish between the different impacts of light on our eyes. Photopic vision is the vision of the eye under well-lit conditions. In humans and many animals, photopic vision allows color perception, mediated by cone cells, and a significantly higher visual acuity and temporal resolution than available with scotopic vision. Photopic lux is the relevant metric for evaluating a visual effect. Melanopic lux, on the other hand, measures light?s impact on the release of melatonin, which is linked to the amount of blue light in the spectrum.
The spectrum of daylight provides a good range of colours, and delivers high levels of photopic and melanopic lux. Designers should also take into consideration that artificial sources of light that appear visually bright may not have the same biological effect because their spectrums are strong in some colours and weak in other colors.
For example, in a hospital where lights are off at night for the benefit of patients, nurses should come to a brighter area for 10 minutes every hour to get enough light to keep them alert at night.
LED lighting systems can be programmed to meet the needs
As we know that daylight increases the level of our activity which then reduces with sunset. Then at night, the body changes over to a relaxed sleeping mode. Biologically effective lighting can simulate this natural process.
Advanced LED lighting systems can be programmed or preset to do this task. With various dynamic spectral components and illuminance levels, they can be programmed to imitate the course of the day and stimulate body responses.
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