6 ms·

Given that the lasers are light shining in a straight line, and that they're presumably calibrated to intensities the eye can deal with (otherwise we couldn't s

Given that the lasers are light shining in a straight line, and that they're presumably calibrated to intensities the eye can deal with (otherwise we couldn't see them/they'd be less sharp) there won't be any more long term effects than just normal eye use. Our eyes are designed to let light in. The power level of lasers that can run all day on a 350mAh battery they share with some electronics is going to be miniscule, like maybe a fraction of a milliwatt of power. A common laser diode available right now that outputs 1mW continuously consumes about 36 mA of power to do that. Three lasers outputting 1mW would consume roughly 363 or 108mA, so a 350mA battery would only power those three lasers for about edit 3.4 hours, with nothing left for the electronics to use. Less than 1mW is not much, even for a laser, and at visible wavelengths it's not going to transfer enough heat to even measurably change the temperature of the human eye, much less damage it.

Ajedi32 7y ago
But don't lasers need to scan in order to draw a full image (vs just a dot)? Doesn't that necessitate making the actual laser beam brighter than other light entering your eye? Are there any negative consequences to having a bright light scan over your retina quickly vs a dimmer light shining on your entire retina at once? What happens if the scanning mechanism fails and the laser ends up shining on one tiny point in the center of your eye for an extended period of time? Lots of interesting safety questions unique to this particular display technology.
- Accujack 7y ago
  Remember that A) The laser is close to your eye and shining directly in and B) It's coherent, so it's focused on a single small spot. It doesn't have to be so much brighter than all the light around you given those things.
  - Ajedi32 7y ago
    But it isn't focused on a single small spot; it has to scan across multiple small spots in order to form a recognisable 2d image. If it were just focused on a single small spot the entire time, all you'd see is a dot. That means one of two things must be true. Either a) the beam is way brighter than other light entering your eye, such that it delivers in a single focused beam the same amount of energy that would otherwise be distributed evenly across the surface of your retina if you were viewing natural light. (Thus the questions I posed in my previous comment.) Or b) the beam is the same brightness as other light entering your eye, meaning the amount of energy in any individual pixel is far _less_ than what your eye receives from natural light. (I imagine this would make the image appear very dim.)

Ajedi32 7y ago

But don't lasers need to scan in order to draw a full image (vs just a dot)? Doesn't that necessitate making the actual laser beam brighter than other light entering your eye? Are there any negative consequences to having a bright light scan over your retina quickly vs a dimmer light shining on your entire retina at once? What happens if the scanning mechanism fails and the laser ends up shining on one tiny point in the center of your eye for an extended period of time? Lots of interesting safety questions unique to this particular display technology.

Accujack 7y ago
Remember that A) The laser is close to your eye and shining directly in and B) It's coherent, so it's focused on a single small spot. It doesn't have to be so much brighter than all the light around you given those things.
- Ajedi32 7y ago
  But it isn't focused on a single small spot; it has to scan across multiple small spots in order to form a recognisable 2d image. If it were just focused on a single small spot the entire time, all you'd see is a dot. That means one of two things must be true. Either a) the beam is way brighter than other light entering your eye, such that it delivers in a single focused beam the same amount of energy that would otherwise be distributed evenly across the surface of your retina if you were viewing natural light. (Thus the questions I posed in my previous comment.) Or b) the beam is the same brightness as other light entering your eye, meaning the amount of energy in any individual pixel is far _less_ than what your eye receives from natural light. (I imagine this would make the image appear very dim.)