Before you start using your laser engraver, you must take all necessary safety precautions. Injuries from laser exposure can be pretty serious. Irrespective of the laser machine you are operating, it is important to take the necessary precautions to avoid any preventable incidents.
But is laser engraving eye protection really necessary?
It actually is very important to protect your eyes when using a laser engraver. Any exposure to a laser beam, whether it is direct, scattered, or reflected, can harm your eyes. If you point the light from the laser engraver into your eyes, it will go through the pupil and focus on the retina. Even a milliwatt laser engraver dissipates light energy that is three times stronger than the sun’s rays. Exposure to such extreme light by even a fraction of a second can injure the retina, cornea or the lens in your eyes. The actual damage depends on the focus setting of the eye, the exact place the beam hits and the amount of energy absorbed, the wavelength of the beam, the time of exposure, and the distance from the laser source.
And this is where laser eye protection goggles come in handy. Goggles create a protective barrier between your eyes and a laser beam by only allowing the light of a certain wavelength to go through. Although severe eye damage is quite rare among laser operators, it is always a looming risk. Unless you want to join the list of people with eye issues because of exposing their eyes to laser light, make sure to always use laser safety eyewear. In essence, the goggles only allow the light of certain wavelengths to pass through and lock the other light out.
By filtering the light, the goggles block out any direct, scattered, and diffused light from passing through. The lens used to make laser eyewear is laced with special dyes and chemicals that enable them to filter the light. Granted, some laser eye protection goggles are dark and hard to see through but it is a small price to pay to guarantee the safety of your eyes. Here is a link to one I found on Amazon that works great with all laser engravers.
The United States Occupational Safety and Health Administration is serious about protecting American citizens from the effects of laser exposure. As a result, they require anyone operating a class 3b and Class 4 laser engravers to wear safety glasses. Laser safety eyewear comes in different wavelengths suited for different types of lasers. You should, therefore, take the wavelength of the laser beam into account when purchasing your safety goggles.
How laser radiation affects the eye
The human eye is extremely sensitive to any type of laser radiation. Here is how laser radiation can affect the retina, the cornea, and the lens.
- The retina: the retina is a thin layer of tissue located at the back of the eye, adjacent to the optical nerve. Its work is to receive focused light, convert it to neural signals, and send them to the brain for visual recognition. Visible laser light of wavelengths between 400 and 1400 nm can cause damage to the retina. These wavelengths are scientifically referred to as the retinal hazard region. Visible laser light focused on the retina by the lens is concentrated on the exposure of up to 100,00 times. This can easily damage the tissues of the retina which unfortunately don’t regenerate. What this means is that retinal damage, especially that of the central portion, fovea, and macula, is permanent.
- Cornea and lens: The cornea of the eye transmits visible light to the lens which in turn, focuses it on the retina. Because of the roles these two play in the eye, they too, suffer eye damage when they come face to face with harmful laser beams. This can be through photochemical damage (denaturing of proteins) or thermal damage (caused by heating or burning of the tissue water and tears of the cornea or lens.
Types of laser radiations
Laser radiation can either be direct, reflected or scattered. Each of these affects you in a different way. Let’s briefly go over each of them:
- Direct radiation: this is contact with a beam emanating directly from a laser source. This type of optical radiation can either be visible or invisible and can burn or denature proteins in the eye region. It can also lead to photochemical reactions in the eye tissues, depending on the wavelength of the radiation.
- Indirect/reflected radiation: this refers to a laser light that originates from a reflected beam. Even if the beam is oriented to a specific workpiece, the reflected light energy can cause some harm. Expectedly, this carries a fraction of the energy dissipated by direct light but it can still damage your eyes.
- Scattered radiation: scattered light has a number of similarities with reflected light except that it originates from a diffuse surface rather than a reflected one. A perfect example is if you walked into a dark room and turned on your flashlight. The light from the flashlight will instantly brighten the room. Because the scattered light beam is reflected in numerous directions, it doesn’t carry as much energy as the preceding types. But scattered radiation is still harmful to the unprotected eye.
Factors affecting the extent of eye damage when exposed to a laser radiation
When the eye is directly or indirectly exposed to a laser light beam, it can suffer temporary or permanent damage depending on several factors:
- The wavelength of laser radiation: The most important factor is the wavelength of the light energy. Typically, exposure to laser radiation of wavelengths of less than 400 nanometers and more than 1400 nanometers causes cataracts and burn injuries. The reason is that the cornea and lens of your eyes absorb the light energy and heats them up. Depending on the focus of the retina radiation, the damage will be varied. An eye injury to the fovea may lead to permanent blindness while an injury to the peripheral areas of the fovea is less severe.
- Laser power: expectedly, the higher the laser power, the worse the level of eye damage. Blinking may not do much at this stage. Anything more than 10-20 milliwatts for wave lasers causes retinal damage in case of a direct hit. If you stared straight into a laser, the burn will be right at the center of your vision. In severe cases, you could lose your central vision and experience permanent blindness.
- Distance from the laser source: another factor affecting how much eyes get damaged from laser radiation is the distance between your eyes and the source of the laser beam. The further away you are from the laser source, the less severe the eye damage. Even with the same wavelength, a laser beam that can instantly damage the retina at close range does little harm to someone observing it from a long-distance away.
My number 1 recommendation for laser engraving eye protection
The LP-Laser Pair glasses (Amazon link) will do a pretty good job of protecting your eyes from laser beams. What makes it really unique is the wrap-around design which means your eyes will not only be protected from the direct laser beam but from the light beams that get reflected on the goggles as well.
Before you get overexcited about the prospect of launching your laser engraving business, make sure you have taken all necessary safety precautions – like protecting your eyes from laser radiation. Otherwise, your business will bring you more harm than good. Wearing safety goggles every time you are using a laser engraver will ensure that you do not damage your eyesight and that will help you to continue making those eye-catching laser engraved items for a long time.