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Melanopic Daylight Efficacy Ratio (m-DER)
More than color temperature
More than color temperature
m-DER measures how effectively a light source wakes your brain, boosts productivity, or eases you into relaxation and sleep across scenes — benchmarked against reference Daylight at 6500K.
Unlike color temperature, m-DER is a practical way to judge the right light source for a scene and purpose — avoiding the metamerism you get when rating light by Kelvin alone.
Unlike color temperature, m-DER is a practical way to judge the right light source for a scene and purpose — avoiding the metamerism you get when rating light by Kelvin alone.
Melanopic Equivalent Daylight Illuminance (m-EDI)
“Non-visual biological lux”
“Non-visual biological lux”
Measured at eye level, m-EDI shows how much daylight-like strength a light source delivers to your body clock — the key driver of human behaviour.
Though also measured in lux, m-EDI captures the non-visual biological effect, not just visual illuminance.
Yuji Lighting grounds its products in melanopic lighting science and documents the parameters for rigorous lighting design.
Though also measured in lux, m-EDI captures the non-visual biological effect, not just visual illuminance.
Yuji Lighting grounds its products in melanopic lighting science and documents the parameters for rigorous lighting design.
Suited to variable applications, Yuji Lighting's extended m-DER range lets you benefit across scenes.
Create the right m-EDI
m-EDI should be managed per scene and time of day. The reference values are based on a typical 32-year-old; Yuji Lighting then adjusts the specs with correction factors for each project, using its extended m-DER products.
OUR OFFICE
Beijing Yuji International Co., Ltd.
Room 1502, Building No.6
Jia No.2 North Xisanhuan Road
100081, Beijing, China
Room 1502, Building No.6
Jia No.2 North Xisanhuan Road
100081, Beijing, China
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