How does a laser pen hurt the eye?

Recent research warns that cheap laser pens that are widely sold in the market can hurt eyes.

Laser pens are hand-held devices that are shaped like a pen, mainly used to indicate distant points of interest with a fairly strong light line. They are widely used in many places, including offices, schools and the whole family.

Researchers at RMIT University in Melbourne have purchased four models of red and green laser pens, all of which cost under US $ 30 in Australia and an average of US $ 22.9.

All four models of blue laser pens have beams above 1 mW, maximum safety limits in Australia. Tested laser pen models even surpassed this safety level by 51-127 times. Therefore, they can harm the eyes.

Light from a laser pen can blind light temporarily.(Illustration).

With the red sample, 3/4 samples are within the safety limit.

With a blue pen sample, exceeding the excessive safety limit can cause serious retinal damage. Red is less problematic because light is not concentrated like blue. Although there are still some risks with red, the normal human reaction to light is blinking and turning away, thus avoiding a lot of permanent damage caused by light.

These types of laser pens are of concern because they are widely sold , anyone can buy them at stores, including children.

Although research is done in Australia, the US Food and Drug Administration also expressed concern about this type of pen. In December 2015, the agency issued a warning about using laser pens, especially for those who use them as toys.

FDA regulations limit the strength of light in a laser pen to about 5 mW. Even at the limit of 5 mW, a laser pointing straight into the eye can cause temporary blindness.

The FDA said many cases of eye damage due to laser were not reported. The agency also warned that children 's eyes are most sensitive to this type of device and the eyes of adults can be similarly compromised.