earticle

영어

According to recent research result that light not only offers psychological and emotional stability to an occupant, but affects human’s health, efforts to improve the indoor lighting environment are increasingly made. Looking into existing studies, lighting’s hardware performance has been evaluated using high-priced measuring equipment in order to identify the characteristics of suitable light according to space type and resident’s activity, or user satisfaction has been assessed through a survey method. However, efficiency is low from the cost and reliability aspects, since these methods are dependent upon high-priced measuring equipment, the size of patent group and survey questions. This paper implements a smartphone-based light quality evaluation system through which light characteristics can be measured or quality can be evaluated anywhere, anytime using a mobile device that a user always possesses, and such a system that supports readjusting to the user-preferred lighting environment depending on situation. The proposed system’s processing process is as follows: The smartphone located around a user measures the currently-serviced light characteristics from the embedded RGBW color sensor. The RGBW sensing data are converted into tristimulus values XYZ, and then color coordinate xy, color temperature CCT and illuminance Y are calculated. Lastly, this study proves the proposed system’s performance by evaluating whether the lighting environment suitable for the current situation is serviced, based on KS Illuminance Standard, and Naoyuki Oi’ graph.