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by Accujack 2320 days ago
Just look away. It's just a display device, so at most it's going to display confusing pictures.

It's not possible to "hack" more output power into lasers with software changes. Would that it was. You can change the duration of the beam, but you can't pulse the beam without a Q switch in a way that changes the instantaneous power.

1 comments

In the normal operations, the laser will scan across the retina without long dwell times at a single spot. Software is likely able to cause the laser to track a single point on the retina (I expect that the device needs some sort of an eye tracker and thus a camera aimed at the eye). I don't know if that can produce a harmful power density.
Given that it doesn't harm the retina when scanning, I'd say "full white" is the best it could do, which could be surprising and a bit uncomfortable, but not actually damage the eye.

Picture your monitor going all white... bright for a sec, but that's about it.

Given that it's scanning the duty cycle as seen by any part of the eye is very small. If the perceived brightness was a function of power density averaged over time, then it would very obviously have to be able to be much brighter than "full white" to create the full white experience[^].

[^] in reality the perceived brightness is somewhat higher than the mean (i.e. a light source that's twice as bright with twice smaller duty cycle appears brighter). I'm not sure how large an effect that is, and whether it has anything to do with pupil size adjustment.

> Picture your monitor going all white... bright for a sec, but that's about it

I remember when a CRT monitor would mess up and stop scanning right the white point in the middle was much brighter than the normal brightness, I was always worried it would burn in and would shut off the monitor right away