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An April 12 2018 story says that although “[s]evere torture and unscientific handling” can cause problems, that laser pointers also may have been used recently by “a mysterious group with vested interests.”
According to the story, “There were complaints that light beams were shined continuously from a distance into the eyes of elephants paraded at the Sree Padmanabhaswamy Temple in Thiruvananthapuram and some other local temples in Thiruvalla and Pathanamthitta. It was alleged that the jumbos turned restive and violent after being blinded with the high-powered laser pointer.”
The story includes a 47-second video clip of an elephant refusing to get onto a truck, while a dot moves around on and near the elephant.
COMMENTARY FRO LASERPOINTERSAFETY.COM
An analysis indicates that the moving dot is not from a laser, but is from internal reflection in the camera lens of a bright light in the scene.
The screenshot below, from one second into the video, shows the dot circled in green, and a bright light circled in red.
As the video is played, the dot moves around. Its movements are correlated with the bright light. For example, when the elephant’s body blocks the light, the dot disappears. Because it is a reflection, it moves opposite to the light, and its movement also changes based on the tilt of the camera lens.
In addition, the dot appears yellow or white. This correlates with the light color. Yellow is very uncommon for laser pointers, while there are no “white” laser pointer beams. A green or red dot would indicate an actual laser.
While there may be other incidents of laser pointer misuse in Kerala, the moving dot in this particular video does not, in the view of LaserPointerSafety.com, show a laser dot or any actual (real-world) light on the elephant.
From Manorama Online
A December 2006 incident has come to our attention. A 15-year-old Japanese boy suffered a retinal injury and visual loss after deliberately looking into a 5 mW violet (410 nm) light emitting diode for a total of about 40 seconds. The LED was in a pen was sold as a toy called “Secret Pen”. The toy appears to consist of an LED light which can excite ink that is invisible under ordinary light but which fluoresces under ultraviolet and near-UV light. The 410 nm wavelength caused photochemical damage to the retina.
According to a 2011 paper in Retinal Cases & Brief Reports, the LED was aimed into the teen’s eye from a distance of about 1 cm. It was held there for about 20 seconds as he deliberately stared into the light. This exposure was repeated the next day. About two weeks later, decreased vision (20/50 on the Snellen scale) was noted in the right eye.
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