HLS    
Healthful Lighting Society
Société D'éclairage Salubre
   
 
 

Latest news


 
Free download of Phone APP to assess the non-visual functions of lighting environment

Healthful Lighting Society has developed a free download Android phone APP called "HLS Circadian Light", which is based on the circadian metrics proposed by Lighting Research Center at Rensselaer Polytechnic Institute. It calculates Circadian Stimulus (CS) and Circadian Light (CLA), as well as the bad blue light percentage of the blue light spectrum.

It is intended to assess the non-visual functions of lighting environment in the field, so that a suitable design of light sources and light levels can be devised accordingly.

Please click here to see the software details.

         


 
  Theoretical model of healthful LED lamp

A theoretical model of healthful LED lamp is proposed to increase the effect of Circadian Stimulus (CS) on human body and reduce eye strain, and at the same time to minimize the impact of "Blue Light Hazard". Its performance, compared with standard LED of daylight color (like 5000K CCT), include these two major areas,
  1. Moving the peak blue wavelength from 450 nanometer to 464 nanometer, which is most sensitive to suppress the body from secreting Melatonin and reduce eye strain.
  2. Reducing the emission of bad blue light to 15% of total blue light spectrum.
Please click here to see the details of this healthful LED lamp.