*m-DER (Melanopic Daylight Efficacy Ratio) is a metric to quantify how effective a light source is at stimulating the melanopic system in comparison to standard daylight. The value greater than 1 means it is more effective than daylight at stimulating melanopic receptors.
*M/P (Melanopic/Photopic Ratio) is a metric used to compare the melanopic and photopic effects of a light source. In evening or nighttime settings, light sources with a lower M/P Ratio can minimize disruption to melatonin production and promote better sleep.