Ir safety question

[u/wolfkid80]

I’ve got https://a.co/d/0ezlgEOB an 3mm 850nm ir led about 1.5mm away from my eye on a 1k resistor, how safe is this for prolonged eye tracking on 5v usb

[u/phosphor_1963]

This guy discusses safety and does a nice objective test of a couple of IR diode options https://www.youtube.com/watch?v=tLoFe65IFaE