White - Royal Blue LED light ratio for color temperatures of 10000K, 12000K, 14000K, 16000K and 20000K

A number of lighting applications pose a challenge for white LEDs because of the color temperature required.  While most white LEDs on the market have a color temperature in the 2700K-6500K range, applications such as aquarium lighting, ask for color temperatures of at least 10000K and sometimes as high as 20000K.

Aquarium LED lighting with light of strong blue tint (color temperature over 10000K)

 To obtain with LEDs white color of temperature higher than 10000K we need to use a combination of white and royal blue LEDs. The table below will show the ratio between royal blue LED spectral power (in mW) and white 4000K LED luminous flux (in lumen) needed to obtain color temperatures of 10000K, 12000K, 14000K, 16000K and 20000K.

Desired color temperature	Royal Blue 450nm LED (mW)	White 4000K LED (lumens)	Royal Blue 455nm LED (mW)	White 4000K LED (lumens)
10000K	1	0,89	0,92	0,92
12000K	1	0,8	0,83	0,83
14000K	1	0,75	0,77	0,77
16000K	1	0,72	0,74	0,74
20000K	1	0,675	0,69	0,69

Explanation:

For a color temperature of 12000K for each mW of spectral power from a Royal Blue 450nm LED we need 0.8 lumen. If the Royal Blue LED has 455m we need 0.83 lumen.


Sample calculation with Cree XT-E 450nm Royal Blue LED and Cree XP-G 2 LED, which you can find at LedRise.

Desired color temperature	Royal Blue LED 450nm	White 4000K LED
10000K	One Cree XT-E 500mW at 350mA	Two Cree XP-G2 4000K at 600mA
12000K	One Cree XT-E 500mW at 350mA	Two Cree XP-G2 4000K at 525mA
14000K	One Cree XT-E 500mW at 350mA	Two Cree XP-G2 4000K at 500mA
16000K	One Cree XT-E 500mW at 350mA	Two Cree XP-G2 4000K at 475mA
20000K	One Cree XT-E 500mW at 350mA	Two Cree XP-G2 4000K at 425mA

You will need a programmable LED Driver for the white LEDs as the one you can find in our shop:

Programmable constant current source 350-2000 mA, 10-20W output CLSD-020

Programming box for constant current source KSQ CLSD-020

Disclaimer:

The values in this post are theoretical and where obtained using a Color Calculator Software from a major LED manufacturer.  Due to the limitations of LED binning and labeling the actual result in real applications might vary. 

If you want a calculation for other LED types please contact us.