Dim-to-warm (pWM modulating) flexible strip
Wellbeing has become a major pursuit in modern residential lighting, and the taste of conventional light source of halogen or incandescent is still desired even in the solid-state lighting era. Imitating the color and brightness change when dimming the halogen or incandescent is the most direct way, however, the so-called “dim-to-warm” LED products from the general market ignore the essential purpose of such a simulation.
A practical dim-to-warm product should not only care about the color temperature change, but also the circadian rhythm, spectral quality and dimming process. The intention is to create a most comfortable lighting environment both for visual and non-visual responses instead of simply color/brightness changing.
By deeply understanding the correlation between the spectrum and human biological response, Yujileds® introduces its unique Dim-to-warm LED solution with a specially designed tunable white light LED and dimming process. This dim-to-warm product is applied as a flexible strip to achieve the full compatibility for different install environments.
Specialized spectra for optimizing the M/P (Melanopic/Photopic) ratio
M/P ratio is the critical factor that affects the alert or relaxes stimulus at the biological level. For any spectral power distribution, the ratio M/P is introduced as the melanopic spectral factor, which indicates a direct responding of a lamp to human’s synchronization of circadian clocks to light/dark cycles, sleep propensity and pineal melatonin production.
For matching with melanopic sensitivity, Yujileds® designs the “SLEEP spectrum” to minimum the M/P ratio, which promotes the secretion of melatonin, and designs the “RELAX spectrum” to achieve a balanced lighting effect both for comfortable environment and sufficient illumination with suitable color temperature.
Different spectral patterns give significantly different M/P results, Figure 26 indicates the typical M/P ratios from various sources. Yujileds® Dim-to-warm RELAX has an even lower M/P ratio as 0.57 than the sunset, and the SLEEP has the M/P ratio as 0.30, lower than a halogen lamp.
|Light source||M/P ratio||CRI - Ra|
|Standard LED (3855K)||0.82||80|
|Incandescent lamp (2810K)||0.64||100|
|Yujileds Dim-to-warm RELAX||0.57||97|
|Yujileds Dim-to-warm SLEEP||0.30||93|
Super comfort dim-to-warm CCTs of high CRI 3000K – 1800K
By dimming from the RELAX to SLEEP model, the color temperature is tuned from 3000K to 1800K accordingly, thus the Dim-to-warm LED strip creates a naturally comfortable lighting scene. With a maximum power density of above 5.0W/ft, the strip could serve as an illuminating lamp as well as a cozy atmosphere creator when it dims and gets warmer.
At the RELAX mode of 3000K, the LED offers the color rendition ability as ultra-high CRI of 97, and tuning to the SLEEP model does not compromise to the quality and it still maintains the CRI as high as 93. With this dimming effect, it turns living, reading, indoor leisure and sleeping into a pleasant and enjoyable experience.
Unique dimming method for ultra-smooth regulation
Unlike a standard bi-color LED strip, this dim-to-warm LED strip simplifies the connection and control as only one pair of positive/negative anodes of 2-pin design with the help of high precision transistors. Thus it can be controlled by a standard driver but both brightness and color adjustments are achieved simultaneously.
In addition, with the optimized method, the dimming from the RELAX to SLEEP model performs ultra-smooth, which does not bring any abrupt effect compared to a general dim-to-warm product on the market, Yujileds Dim-to-warm technology makes the whole dimming process naturally.
Optimized design of the flexible strip
This dim-to-warm strip has also optimized in designs including introducing 3oz copper electrodes, 1% accuracy resistors, high precision transistors and 0.4mm spacing between neighboring emitters in a pair, which eliminates the visible light spots during the dimming process, and a variety of PWM compatible controlling units of DALI, TRIAC, 0/1-10V dimmers.