To prevent the cyan dip, the leds feature an especially developed 420nm blue led, so shorter wavelength than normal white leds (450nm) and longer than Yuji uses for their VTC series (400nm). For most flashlight use, these midpower leds are too weak, but perhaps they come out with a high power version some day :)
Here's what they write about it:
Ultra-High CRI White LED (Optisolisâ˘)
Optisolis⢠achieves Ultra-High CRI with a spectrum that demonstrates the closest match to that of the standard illuminant. Optisolis⢠is optimized for the general lighting market and is accomplished by using Nichiaâs own blue chip and phosphor technology.
Manufacturers can utilize Optisolis⢠and trust in a spectrum where all colors are reproduced to the color seen under a standard light. (Figure 1) Also, color rendering index has been significantly improved compared with the current products for general lighting. (Figure 2) Most importantly, since UV emission is essentially non-existent in the spectrum, the degradation of irradiated materials can be reduced dramatically compared to that of other light sources containing UV emission, including other market available LEDs.
Target applications include Museum and Art Gallery Lighting, where the highest CRI is preferred, but UV radiation and light sources can be detrimental. Additional applications could include Color Evaluationďźe.g. painting, printing), Commercial Lighting (e.g. retail, etc.) or anywhere Ultra-High CRI is desired.
Figure 1.
Example of spectrum (TS 25°C) *1
Figure 2.
Example of Color Rendering Index (n=1) *1
*1 The above values are from measured samples and are for reference purposes only, these values are not guaranteed.
*The photos might not exactly be the same as the original.
*Please refer to CIE 1931 chromaticity diagram.
*The 'Typ.' in the products page indicates typical value so that is not under guarantee.
Yes 219D newer version of 219C, I have no interest on it. The max CRI is currently only Ra8000
If youâre going for performance upgrade from 219C itâs better to use 319A R8000. Unless tighter beam is what youâre after.
Surface mount leds with about half the lumens of run-of-the-mill 5730s. I recently had the pleasure of reflowing a 100-pack of them on an electric induction stove. Time consuming taskâŚ
Question with regards to these is footprint and boards' availability.
Maybe enough violet for violet stuff to shine, we'll see. I wonder how actually good are modern leds in this regard (remember this sort of violet we see on our displays really isn't violet).
I think so too. But canât give any suggestions until I tested them. Being a low power LED (away from BLF habit) any non DTP boards should serve it well. Itâs
overall footprint is symmetrical unlike Yuji but the the anode-cathode pads arenât.
If heat output is low enough, you could design your own pcb and make a cob lantern out of it. Itâd take an ungodly number of these ledâs to get decent output and efficiency though. Iâd want a thousand emitters, maybe a lot more, and thereâs no way Iâm reflowing that many emitters.
It seems unsuitable for light bulbs. Maybe itâd be okay for panel lights, and excellent for lighting film sets. Computer monitor backlighting may be a good application.
This Graph doesnât make sense to me. This new LED should have a lower color temperature. There is more red spectral content in relation to the blue peak compared to the other LEDs.