Creme of the Crop 445nm Diodes

[krazer]

I didn't realize that there was quite that large a difference in luminous efficiency at 440 vs 450nm, I will work in adding wavelength sensing to the rig and hopefully will be able to bin the next lot of diodes I test by efficacy. The data should be available early next year.

In the mean time, these diodes are going fast, down to 5 of them left

[MechEng3]

I never realized the wavelength could shift so far with the same wafer design. I guess the cleaving is done in a rushed status...revealing the new oddity and not so close tolerances held on the final product. Nice that you are doing so much research....Thank you for sharing information with us. Still pondering decanning one and applying different optics to see what can be done...I guess no one has fiber launched one yet? I have the micro lens for the diode's window if anyone want to harvest it. I dropped the one I tried to remove. It is still MIA somewhere on the table.

[-bart-]

@ solar flare

445 nm 0.0424000 0.0433000 0.0441000 0.0450000 0.0459000

0.0433 / 0.0424 = 1.02 therefore 446 appears 2% more bright than 445.

[Solarfire]

@ solar flare


0.0433 / 0.0424 = 1.02 therefore 446 appears 2% more bright than 445.

Unless you have other information, light intensity to the human eye has to be viewed over the entire spectrum of visible light in order to determine a percentage level within a part of this spectrum. The chart below shows this perception of light intensity in dependence to wavelength. Going from 555nm (100% borderline) to 380nm (0% borderline) the spectrum of 440nm to 450nm takes up 0.86% of the perceivable intensity level of the human eye, making it hard to impossible to differentiate. But I do stand to be corrected.

[-bart-]

This (medialas?) table does not state photopic-, scotopic- or mesopic vision, but I assume this table to be photopic. That makes it not particular usefull.
For lasershows mesopic conditions are most common. To make matters worse, the mesopic peak shifts with lighting conditions.

Nonetheless, I think the whole point of the above table is to calculate relative brightness in photopic vision, (what else?)
1 watt of 445nm will resemble 42,4mW of 555nm.
1 watt of 446nm will resemble 43,3mW of 555nm.
Therefore I conclude a 2% increase of perceived brightness.

Looking at various graphs I think the increase in perceived brightness under mesopic condition will be even higher.