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What characteristics (wavelength, mW) IR line laser should have to:

  1. be seen by camera module from 15 meters outdoor in day-light too
  2. safe for eyes
  3. line as big as possible
  4. thickness of line should be enough to see from 15 meters 1280×720 camera

Camera characteristics:

  1. 1280×720
  2. 60 fps
  3. I don't know what lens characteristic should be (relative to laser?)
  4. I will use interference filter of laser wavelength

Camera module itself

As I understand it should be combination of lens and laser. Blind zone should be as small as possible.

  • \$\begingroup\$ This might not help but I read somewhere that the IR laser in the XBox Kinect is 780nm Class 1 (less than 25uW). I use an IR diode at 15m all the time (the TV remote!) The range under sunlight is a big issue though - once sunlight is falling on your sensor/camera/whatever, there will be too much IR to distinguish the emitter. I've used cardboard shields to prevent this but I'd also be very interested from other opinions on this. \$\endgroup\$ – carveone Aug 28 '14 at 11:12
  • \$\begingroup\$ Some cameras / lenses have IR cut filters, some don't. Check carefully. \$\endgroup\$ – John U Aug 28 '14 at 12:17
  • \$\begingroup\$ @Dave Tweed: That's true, it is a comment and started out that way but thought it was too long for a comment. I suppose it dropped under the helpful answer line. \$\endgroup\$ – carveone Aug 28 '14 at 12:19
  • \$\begingroup\$ @JohnU i know, my camera will be without) \$\endgroup\$ – Kracken Aug 28 '14 at 12:21
  • \$\begingroup\$ @carveone, interesting about the Kinect. IR lasers are a lot more dangerous than visible ones because there is no blink reflex from the eye. RE: IR LED's and sunlight. Can you blink the LED and do synchronous detection? Even just blinking and a moderate (Q~10) band pass filter would help. \$\endgroup\$ – George Herold Aug 28 '14 at 16:40

I'm going to put this as an answer, it feels more like a comment. (they are getting too long)

If I was designing a laser system for outdoor use with public access, then I'd have to assume a worse case scenario. In this case that would be some idiot sticking a screw driver into the spinning mechanism, stopping it, and then looking in to see how it works. In which case 5mW is too much. 25 uW sound's like a safe number.

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