There are 850nm IR LEDs that have non-zero output near 750nm, see;
http://www.optodiode.com/pdf/OD-850W.pdf
The eye has non-zero sensitivity near 750nm. Together, there is some=20
very slight viability to (relatively) high power levels such a looking=20
directly at the LED up close. Most LEDs have their power distributed=20
across a relatively large chip area and therefore cannot be focused to a=20
very small spot on the retina so the power density probably will be well=20
below any damage threshold. (I say probably, cause as technology=20
develops, they squeeze more power out of the chips.)
However, some communication (and other) LEDs (such as those made for=20
fiber optics) have the light generated in a very small area, similar to=20
a laser but without the beam properties, these can be focused to a much=20
smaller area such that the damage threshold may be more nearly=20
approached with careful choice of optics. However, the fact that the eye=20
is always flickering around prevents even this from being much of a=20
problem.
The hazards from near IR such as 850nm are purely thermal as far as I=20
know (I used to design ophthalmic instruments using these wavelengths so=20
have studied such matters. When you get towards blue light there are=20
photochemical hazards.
Looking forward,
Al Shinn

--=20
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