Many Green Laser Pointers Pose Greater Hazards Than Labeled

(ISTV) -- Laser pointers can enhance presentations, point out constellations in the sky, and even occupy a playful cat. They’ve become so common that some consider them completely harmless. But many laser pointers can do serious damage to the eyes if not used properly.

Josh Hadler, a physicist at the National Institute of Standards and Technology, said, “They’re very useful as demonstration aides, amateur astronomy uses. They’re ubiquitous now, you can buy them anywhere.”

But be careful where you point them! Hadler said a new test that measures the energy from pointers showed that some laser pointers, easily available in stores or on the Internet, emit potentially dangerous levels of energy.

“A fifteen year old kid bought a laser pointer off the Internet, he bounced it off of a mirror and it swept across his face faster than he could blink -- permanent retina lesions in both eyes,” recalled Hadler.

Out of 122 lasers tested by NIST, 90 percent of green laser pointers were not within federal safety guidelines and some had power levels more than 10 times the legal limit.

“The problem is most of those devices aren’t what they claim to be so it’s an inaccurate or insufficient labeling,” said Hadler.

Pointers are supposed to be limited to 5 milliwatts of visible energy, or light you can see, and less than 2 milliwatts of infrared, light you cannot see but can still damage the eye. A power meter revealed that more than half of the pointers tested emit more than twice the limit of infrared light.

Hadler said, “The concern is that these devices are putting out a dramatic amount of optical power, able to concentrate that power very tightly into the human eye, that it can cause injury from a momentary glimpse.”

Consumers who use laser pointers should never point them at anyone’s eyes, including their own, nor should they point them at mirrors or even at windows, which can often reflect the invisible but damaging light.

Researchers also found that many red lasers are not in compliance with federal regulations and put out more visible power than allowed.

The problem could be solved by adding an inexpensive filter to the end of the laser – but consumers should still avoid looking at the lasers directly.