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With a proper lens I think it just might work. You need to get huge focal length to make those pixels work. Then you need illumination because with those focal

With a proper lens I think it just might work. You need to get huge focal length to make those pixels work. Then you need illumination because with those focal length it will be really dim. Then you need to scan the area because your FOV is tiny (but at least you'll get something like 90FPS @VGA res which is enough for AI) so you should be able to see those mosquitoes shining in the air like dust particles in sunlight coming from the window. But then using a laser just insane - anything that has enough energy to down a mosquito will have enough energy to blind someone unfortunate to see the laser or its reflection. I'd go with power LED and some focusing with very narrow focal depth. maybe a lens moved like in optical drives, maybe a MEMS reflector like are used in projectors (but instead of spreading all pixels to cast a projection focusing it in a single point?

iudqnolq 6y ago
> But then using a laser just insane ... I'd go with power LED and some focusing with very narrow focal depth. maybe a lens moved like in optical drives, maybe a MEMS reflector like are used in projectors (but instead of spreading all pixels to cast a projection focusing it in a single point? haven't you just described how to make a laser?
- rowanG077 6y ago
  No a laser is coherent. It has almost the same intensity in it's entire path. If you know the approximate distance you can accurately focus a normal beam of Light into that area. Killing the bug but much safer.
  - iudqnolq 6y ago
    Thanks for teaching me something
  - danielheath 6y ago
    This would protect people standing behind the bug, but if the system mistakenly identified an eye as a bug you would still be delivering a burning quantity of energy focussed on the eye.
LeifCarrotson 6y ago
I've integrated a few laser engravers and laser-cutting CNCs, so let me clear up a couple misconceptions: Lasers typically have a narrow focal length, just like your LED proposal - otherwise they'd damage the optics/mirrors! They're designed to pass a coherent beam of about 10mm diameter through a series of lenses and mirrors. The beam of an engraver might carry 10W of power in that diameter, which is pretty bright, but decent lenses or mirrors with high transmission and reflection won't be damaged. It's safe for both skin and optics until, say, 100mm after it goes through the primary lens. Hopefully at the surface of the thing you're cutting or engraving, it's a spot size of 0.1mm! With 10W of power in that tiny area, even exotic antireflective glass that can transmit 99% of the light will be atomized. If the thing you're cutting/engraving isn't present, then 100mm past the focal plane, it's back to 10mm diameter, and 100mm after that, it's 20mm, and just continues dissipating. It's really pretty hard to focus it back into a coherent beam sufficiently narrow to damage eyesight (much less skin). Yes, the CDRH is really concerned about the possibility of a laser system accidentally lasing a blob of metal into a perfect mirror that will send a coherent beam directly into the eye of an operator standing meters away; I've got laser systems with thousands of hours on them etching reflective foil off of plastic and there's no sign of reflections causing damage to the smoked acrylic that's shrouding the operation. The typical mechanism used to drive laser engravers is more like a HDD actuator that moves the read/write heads - it's called a galvanometer. Basically a mirror on a stick connected to a magnet. A voice coil pulls the magnet +/- 10 degrees or so; They've got sub-millisecond response times so hitting a moving mosquito would be no problem! I propose that you suck the mosquitoes through an enclosure with something like a box fan or duct booster. Make sure the entrance and exit has to go through a couple right angles so your laser optics are never visible to someone outside the box. Backlight the inside of the box so that instead of AI to see whether the thing in your camera FOV is a mosquito or a songbird really far away, you just zap any black mosquito-sized blobs that pass through.
- uuidgen 6y ago
  I just played a bit with CNC engraving and laser projection, so don't have that extensive knowledge, but AFAIK: Even with your example of 10W, 10mm beam it has a bit more than 0.12 W/mm^2. Hundred times the power output from the sun. Even if we use a 1W laser, which should be enough for a mosquito, it's still like looking into the sun with a 10x magnifier. And as you said - you focus the spot in 0.1mm with a small focal length - that's great for cutting or engraving but won't deliver enough energy to a mosquito 5 meters away unless you start with the same beam size, then focus it 5 meters away at the target. Only then it will need another 5 meters for the beam to return to the initial diameter and many more times that to finally be safe. What I propose is a big reflector and aiming optics directed at it(a bit like a satellite antenna). I didn't do the math, but tens of centimetres or even more than a meter of dimeter. Let's say 50cm==500mm. Then if you want to focus it to 5mm at 5 meters it will have less than 10mm at +-5cm. You could do the same with a laser but you just don't need to. Instead of 1W laser you can use a 10W powerled, have the same energy at the target but it will be much safer at almost every stage before it. And what most people think about when they talk about shooting mosquitoes with a laser is, I think, sending a coherent 5mm beam directly - e.g. from a laser pointer. So you don't have to estimate the distance, but it is even more dangerous.

iudqnolq 6y ago

> But then using a laser just insane ... I'd go with power LED and some focusing with very narrow focal depth. maybe a lens moved like in optical drives, maybe a MEMS reflector like are used in projectors (but instead of spreading all pixels to cast a projection focusing it in a single point? haven't you just described how to make a laser?

rowanG077 6y ago
No a laser is coherent. It has almost the same intensity in it's entire path. If you know the approximate distance you can accurately focus a normal beam of Light into that area. Killing the bug but much safer.
- iudqnolq 6y ago
  Thanks for teaching me something
- danielheath 6y ago
  This would protect people standing behind the bug, but if the system mistakenly identified an eye as a bug you would still be delivering a burning quantity of energy focussed on the eye.

LeifCarrotson 6y ago

I've integrated a few laser engravers and laser-cutting CNCs, so let me clear up a couple misconceptions: Lasers typically have a narrow focal length, just like your LED proposal - otherwise they'd damage the optics/mirrors! They're designed to pass a coherent beam of about 10mm diameter through a series of lenses and mirrors. The beam of an engraver might carry 10W of power in that diameter, which is pretty bright, but decent lenses or mirrors with high transmission and reflection won't be damaged. It's safe for both skin and optics until, say, 100mm after it goes through the primary lens. Hopefully at the surface of the thing you're cutting or engraving, it's a spot size of 0.1mm! With 10W of power in that tiny area, even exotic antireflective glass that can transmit 99% of the light will be atomized. If the thing you're cutting/engraving isn't present, then 100mm past the focal plane, it's back to 10mm diameter, and 100mm after that, it's 20mm, and just continues dissipating. It's really pretty hard to focus it back into a coherent beam sufficiently narrow to damage eyesight (much less skin). Yes, the CDRH is really concerned about the possibility of a laser system accidentally lasing a blob of metal into a perfect mirror that will send a coherent beam directly into the eye of an operator standing meters away; I've got laser systems with thousands of hours on them etching reflective foil off of plastic and there's no sign of reflections causing damage to the smoked acrylic that's shrouding the operation. The typical mechanism used to drive laser engravers is more like a HDD actuator that moves the read/write heads - it's called a galvanometer. Basically a mirror on a stick connected to a magnet. A voice coil pulls the magnet +/- 10 degrees or so; They've got sub-millisecond response times so hitting a moving mosquito would be no problem! I propose that you suck the mosquitoes through an enclosure with something like a box fan or duct booster. Make sure the entrance and exit has to go through a couple right angles so your laser optics are never visible to someone outside the box. Backlight the inside of the box so that instead of AI to see whether the thing in your camera FOV is a mosquito or a songbird really far away, you just zap any black mosquito-sized blobs that pass through.

uuidgen 6y ago
I just played a bit with CNC engraving and laser projection, so don't have that extensive knowledge, but AFAIK: Even with your example of 10W, 10mm beam it has a bit more than 0.12 W/mm^2. Hundred times the power output from the sun. Even if we use a 1W laser, which should be enough for a mosquito, it's still like looking into the sun with a 10x magnifier. And as you said - you focus the spot in 0.1mm with a small focal length - that's great for cutting or engraving but won't deliver enough energy to a mosquito 5 meters away unless you start with the same beam size, then focus it 5 meters away at the target. Only then it will need another 5 meters for the beam to return to the initial diameter and many more times that to finally be safe. What I propose is a big reflector and aiming optics directed at it(a bit like a satellite antenna). I didn't do the math, but tens of centimetres or even more than a meter of dimeter. Let's say 50cm==500mm. Then if you want to focus it to 5mm at 5 meters it will have less than 10mm at +-5cm. You could do the same with a laser but you just don't need to. Instead of 1W laser you can use a 10W powerled, have the same energy at the target but it will be much safer at almost every stage before it. And what most people think about when they talk about shooting mosquitoes with a laser is, I think, sending a coherent 5mm beam directly - e.g. from a laser pointer. So you don't have to estimate the distance, but it is even more dangerous.