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US: Student builds device to automatically shoot eyes with a laser pointer

A 19-year-old Northern Arizona University student posted a YouTube video showing a device he built that tracks a face, and aims a laser beam towards the eyes.

Michael Reeves’ tongue-in-cheek narration states “…it’s really doing its job of lasering me in the eye which is the real innovation here. To my pleasant surprise I found that this machine also solved another of society's problems; the fact that you're not seeing little tiny dots in your vision all day long. I know where to go when I wanted to see little dots, now I can't focus on anything.”

Michael Reeves laser pointer in eye 01
The inset photos show what the camera is seeing (left) and the red box indicating face detection (right)


The laser in the video looks substantially more powerful than the U.S. FDA limit of 5 milliwatts. (However, it can be difficult to estimate laser power from a video. For example, the camera may be more red-sensitive than human eyes which might explain why the beam seems so large and bright.)

Anyone doing this should be aware of the problem of laser pointers often being more powerful than the label states, and more powerful than the U.S. limit of 5 mW.

Fortunately for Reeves’ vision, the laser is mechanically aimed by two devices that move it left-right and up-down. This makes the aiming relatively slow and lagging the facial recognition, so the beam can be dodged much of the time. He moves to avoid the beam, and is hit in or very near to an eye about once every couple of seconds.

The screenshot below shows the camera (blue arrow) and a laser module mounted on two servos (yellow arrow).

Michael Reeves laser pointer in eye 02


As befits a student budget, the housing is an old pizza box. Reeves wrote the facial recognition and aiming program in C#, using Emgu CV, a .Net wrapper for the OpenCV computer vision library.

In about a day, the video received 80,000 views as well as being featured at tech blog The Verge.

From The Verge. Original YouTube video here.

UPDATED April 19 2017: Michael Reeves told C/Net “My eyes are fine. A lot of people seem concerned about that, which I admit is warranted. I used a 5 mW laser diode, and never had it in my vision for more than a fraction of a second."