21 September 2015
We have all most likely been cautioned about the dangers of shining a laser pointer in someone’s eyes. As kids we were warned not to be silly with them, much like we were told not to run with scissors. However many of us would not have been told of the full impact that laser pointers can actually have on our vision if misused.
In 2008, the Australian government introduced strict new guidelines as a reaction to laser pointer attacks on pilots that had recently occurred. These new rules prohibited the sale of any laser pointers over the strength of 1 milliwatt, and anyone found with a pointer exceeding this strength would be seen as possessing a weapon.
Laser pointers are dangerous for three main reasons; they are collimated (light does not diverge like ordinary light), they are monochromatic (one wave length) and they are coherent (every beam is in phase with each other). When white light is projected onto the front of the eye (cornea) it is even across the back of the eye (retina). However, when a laser pointer light is projected onto the cornea it fixates onto a small spot on the retina which can often cause significant damage to the eye.
Lecturer and Researcher at UNSW Canberra Trevor Wheatley has recently conducted tests to show how easy it is for laser pointers over the legal limit to be bought within Australia and his results were alarming.
Wheatley purchased 44 laser pointers online from both Australian and overseas suppliers and tested the strength of each of them, his findings were quite alarming. Out of the 44 laser purchased, only 2 were under the legal power limit and out of these 2 only 1 was labelled at the correct strength. The other lasers were not only labelled incorrectly, but they were over the legal power limit with the highest reading reaching 110 milliwatts (110 x the legal limit).
ABC program ‘Catalyst’ showed a segment on the dangers of laser pointers (aired 14th September 2015) in which they conducted an experiment to show the true impact they can have on the eye. They showed this by shining 2 different laser pointer lights at an inflated balloon and seeing the impact they both had.
When a laser pointer light, at the strength of less than 1 milliwatt (under the legal limit) was projected at the balloon, there was no reaction at all. However, when a light that was over the legal strength was pointed at the balloon, it was only a matter of seconds until it reached 100 degrees and burst.
This has the same effect on the eye, except instead of burning rubber (the balloon) the laser pointer burns cells. In some instances a laser pointer can cause complete vision loss in the eye. In extreme cases it can even cause macular holes, meaning the light burns completely through the macular.
There are many different lasers in the world, used for many different purposes. At Hunter Laser Vision our Schwind AMARIS 750S is leading technology for eye laser surgery. In refractive surgery we are focused on the lens at the front of the eye, the cornea. The cornea is then reshaped by the laser to allow for less dependence on glasses or contact lenses.
You can be sure this laser is superior in all important aspects: Safety, speed, precision, and comfort.