Many people think that only commercial and home lighting can talk about white light. But is it really so?
Let us first understand the CRI.
A color rendering index (CRI) is a quantitative measure of the ability of a light source to reveal the colors of various objects faithfully in comparison with an ideal or natural light source.
Let’s take 3000K CCT LED as an example. These are the test reports of 80 CRI and 90 CRI respectively.
Spectrum
The red color ratio of the 80 CRI is 23.2%, and the peak top of the red light part is about 615nm; the red color ratio of the 90 CRI is 24.2%, and the peak top of the red light part is about 630nm. The height of 660nm, 80 CRI’s is 10% lower than 90 CRI’s. 730nm, 80 CRI’s is only half the height of 90 CRI’s. Therefore, from the spectrum, the 90 CRI LED is more suitable for cannabis growth.
PPF
When driving at 65mA, 80 CRI’s PPF is 0.50579μmol/s, 90 CRI’s is 0.4605μmol/s. At 100mA driving, 80 CRI’s is 0.76659μmol/s, and 90 CRI’s is 0.69374μmol/s. Therefore, from the perspective of PPF, 80 CRI LED is more suitable for cannabis growth.
Taking into account the advantages of both the spectrum and PPF, we guess that the white light of the 80 CRI and the 90 CRI should have the same effect on cannabis growth when driven by the same current. Regardless of the cost, the 90 CRI is used to reduce the current, and the number is increased to achieve the same umol/j as the 80 CRI. However, it may take three 90 CRI LEDs to replace one 80 CRI.
When using 80 CRI LEDs and 660nm, there will be a small wave trough in the 630nm part; but when the 90 CRI LEDs are matched with 660nm, it is a smooth transition.