- LASER EYE SAFETYBACK TO THE BASICS... continued

forge CO2 laser is an example of a laser that falls in this range.

The crystalline lens inside the eye is what we use to focus light onto our retina. This is the part of the eye that everyone will at some point become very familiar with. If you know anyone that uses reading glasses, particularly over the age of 40, this lens is the culprit. The crystalline lens changes throughout our lifetime, becoming denser with age. As this density increases, the flexibility decreases, leading to the near-universal need for reading glasses at some point. The second purpose of the crystalline lens is to protect the retina from UV light, light from around 180nm up to 400nm. Lasers in this range, and UV light in general, cause clouding of the lenses, which is commonly known as cataracts.

The cornea is our window to the world. It’s the front surface of the eye that is the first part of the process of focusing light into the eye. It is made up of northern latitudes as “snow blindness,” photokeratitis can be very painful but generally resolves without permanent damage. the same type of tissue as the sclera (the white part of the eye), and our skin; however, since it is so well-organized light can simply pass through it as it does a clear window. The cornea is sensitive to far UV in the 180 to 315 nm range, as well as the infrared range of light. Damage to the cornea from light is known as photokeratitis and essentially amounts to a sunburn on the front of the eye. Also known in the welding world as “welders flash” and to the

At the end of the day, laser safety really depends upon preventing excessive laser energy from entering the eye. Anyone who uses a laser should be aware of the risks and the precautions necessary to prevent harm to both themselves or others with respect to their specific laser or lasers. One of the most significant dangers associated with lasers is complacency; dealing with dangers that we may not be able to necessarily see even with the laser is in operation.

Laser eye protection specific to each laser should be used in order to prevent reflected or scattered light from the laser from reaching the eye. There are no universal safety glasses for lasers; they must be designed according to the specific wavelength of the laser or they will be ineffective. Additionally, measures must be taken to ensure there is not leakage of the laser light to others that may accidentally be exposed. For particularly high-powered or exposed lasers, this may even involve locking mechanisms to prevent the door to the room where the laser is operating from being opened. Anyone with eyes is suseptable to damage from lasers. One sad story is from a patient that did not take these precautions and became complacent. The patient was a semi-professional hobbyist and artist whose medium was laser cutting. This person ensured that the laser was operating properly in the enclosure, however they did like to look and see the scattered light as the laser was in operation. When they visited my office, they