De-doming and RA for Osram 4715AS IR LED

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yabbayabba
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De-doming and RA for Osram 4715AS IR LED

Hi Guys,
Got a question that I have not found much info on. Has anyone tried de-doming IR LEDs such as the Osram 4715AS? If so what was the effect? Some who tried it said it that while the projected die is smaller it didn’t have any more density. How much wave length shift would I expect, ie 850nm shifts to 800nm? Is it similar to de-doming a white LED. I have a AS in a T67.

Also if I was to put an RA on above the 4715AS will it have the same effect as a RA on a white LED in the sense that it will excite the emitter?

May have a few more questions coming up

Yabba

Lexel
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Dedoming will have no tint shift as no phosphor is used

The 4716AS has a very shallow dome which gives a way smaller projection of the die

https://dammedia.osram.info/media/resource/hires/osram-dam-2496394/SFH%2...

yabbayabba
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Thanks,
Makes sense the 150 deg beam will give a smaller die projection, but wont the advantage with the extra throw be wasted due to the lost spill as opposed to the 90 deg beam?

So if I was to put a RA or wavien collar over my de-domed 4715AS what would the effect be?

The_Driver
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Are you sure about the shallow dome? Normally it should be the other way around. High domes with small emittance angle give you a very small spot and lots of spill when used with a reflector (with an aspheric lens you the will get a bigger spot). Low domes will give you a bigger spot (makes better use of a reflector in my opinion). This can be checked with carclo’s beamshots of their optics and Osram Osslon SSL80 and SSL150 LEDs on their website.

Dutcheee
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I have no info on the dome.
Just don’t combine these or the SFH4725S with a direct drive driver or “test” them directly to a 18650. The will blow immediately. Don’t ask how I know Facepalm

led4power
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Narrow angle LEDs are terrible for reflectors because very small amount of light hits reflector surface.