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Eye protection in laser engraving is an often overlooked yet critical safety measure. Injuries from laser exposure can be quite serious, so you may want to be more careful. Regardless of the laser machine you operate, it is important to take the necessary precautions to avoid avoidable incidents.

Is eye protection really necessary with laser engraving?

Eye protection in laser engraving is very important. Any exposure to a laser beam, whether direct, scattered or reflected, can be harmful to your eyes. When you direct the light from the laser engraver into your eyes, it passes through the pupil and focuses on the retina.

Even a milliwatt laser engraver dissipates light energy three times stronger than the sun’s rays. Exposure to such extreme light for even a fraction of a second can damage the retina, cornea, or lens in your eyes. The actual damage will depend on the focus setting of the eye, the exact spot where 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 eyeglasses come in handy. Glasses create a protective barrier between your eyes and a laser beam by allowing only light of a certain wavelength to pass through. While serious eye injury is quite rare among laser operators, it is always an imminent risk. Unless you want to join the list of people with eye problems due to exposing their eyes to laser light, be sure to always wear laser safety glasses. Essentially, the glasses only let the light of certain wavelengths through and exclude the other light.

By filtering the light, the glasses directly block scattered and diffused light passing through them. The lens used to make laser glasses is laced with special dyes and chemicals that allow them to filter the light. Granted, some laser eyeglasses are dark and hard to see through, but it’s a small price to pay to ensure the safety of your eyes.

How laser radiation affects the eye

The human eye is extremely sensitive to any form of laser radiation. Here’s how laser radiation can affect the retina, cornea, and lens.

  • The retina: The retina is a thin layer of tissue at the back of the eye, adjacent to the optic nerve. His job is to receive focused light, convert it into neural signals and send it to the brain for visual recognition. Visible laser light with a wavelength between 400 and 1400 nm can cause damage to the retina.

    These wavelengths are scientifically referred to as the retinal danger region. Visible laser light focused on the retina by the lens is concentrated up to 10,000 times. This can easily damage the tissues of the retina which unfortunately do not regenerate. What this means is that damage to the retina, especially that of the central part, 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 role these two play in the eye, they too suffer eye damage if they come face to face with harmful laser rays. This can be due to photochemical damage (denaturation of proteins) or thermal damage (caused by heating or burning of the tissue water and tears of the cornea or lens.

Types of laser radiation

Laser radiation can be direct, reflected or scattered. Each of these affects you in a different way. Let’s briefly discuss them all:

  • Direct radiation: This is contact with a beam coming directly from a laser source. This type of optical radiation can be visible or invisible and can burn or denature proteins in the eye area. 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 comes from a reflected beam. Even if the beam is aimed at a specific workpiece, the reflected light energy can cause some damage. This is expected to carry a fraction of the energy dissipated by direct light, but it can still damage your eyes.
  • Scattered Radiation: Scattered light has some similarities to reflected light, except it comes from a diffused surface rather than a reflected surface. A perfect example is when you walk into a dark room and turn on your flashlight. The light from the flashlight will brighten up the room instantly. Since the scattered light beam is reflected in numerous directions, it does not carry as much energy as the previous types. But scattered radiation is still harmful to the unprotected eye.

Factors Affecting the Extent of Eye Injury When Exposure to 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 light energy. Typically, exposure to laser radiation with wavelengths less than 400 nanometers and more than 1400 nanometers causes cataracts and burns. The reason is that the cornea and lens of your eyes absorb and heat up the light energy. Depending on the focus of the radiation from the retina, the damage will vary. An eye injury to the fovea can lead to permanent blindness, while an injury to the peripheral areas of the fovea is less severe.

It is expected that the higher the laser power, the worse the level of eye damage. Blinking may not do much at this stage. Anything over 10-20 milliwatts for wave lasers causes retinal damage on a direct hit. If you were staring straight into a laser, the burn will be right in the center of your view. In severe cases, you may lose your central vision and experience permanent blindness.

  • Distance to the laser source

Another factor that affects the degree of damage to the eyes from laser radiation is the distance between your eyes and the source of the laser beam. The farther you are from the laser source, the less severe the eye damage. Even at the same wavelength, a laser beam that can instantly damage the retina up close does little harm to someone observing it from a long distance.

Conclusion

Before you get too excited about the prospect of starting your laser engraving business, make sure you have taken all the necessary safety precautions, such as protecting your eyes from laser radiation. Otherwise, your business will do you more harm than good. Wearing safety glasses every time you use a laser engraver will ensure that you don’t damage your eyesight and that you can continue creating those eye-catching laser-engraved items for a long time to come.