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The boy was playing with a classmate, trying to dodge the beam. At some point it hit the boy’s left eye. He felt a stinging sensation and became light sensitive.
During a routine eye exam two weeks later, a retinal burn was seen. The boy underwent photocoagulation treatment and will need regular follow-up exams to monitor the eye’s healing, but he did not suffer any vision loss, said Wu Pei-chang, director of the Department of Ophthalmology at Chang Gung Memorial Hospital in Kaohsiung (third-largest city in Taiwan).
From the Taipei Times
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.”
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).
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."
For details, see this LaserPointerSafety.com article in the non-aviation incident section of our news coverage. We are cross-referencing the article in this section as well, for persons who are looking for articles about scientific studies of laser eye injuries.
This is said to be the most serious Norwegian case of laser pointer eye damage. There are about 12 known cases although authorities fear there may be more actual cases.
From the Icelandic Radiation Safety Authority. For the original machine-translated version, click the “Read More…” link below. A Norwegian TV report on the case is here.Click to read more...
However, it turns out that this incident was caused by boys on bicycles, apparently acting without pre-planning and not knowing how the lasers would affect pilot vision. During a Feb. 2011 briefing to the SAE G10T laser safety group , FAA flight standards liaison Patrick Hempen said that the truth about Sydney has not caught up with the news stories: “The attacks are usually spontaneous in nature, perpetrated by careless or malicious persons.”
Hempen said that investigation by US and Australian officials revealed that the Sydney "cluster attack" was caused by youths, riding their bicycles on a golf course at night, who stopped and took the occasion to illuminate landing aircraft. He noted that the youths’ local community had a history of acrimony directed at the airport authority due to the construction of a new runway which caused more flights over their residential area.
Hempen also investigated several laser events in the Mideast and found many of the so-called "deliberate attacks" to be similar; they were “events perpetrated by youths, in a party-like atmosphere, without care or knowledge of the havoc that they were causing.”
Based on a Feb. 1, 2011 presentation to SAE G10T.