The light emitted from a laser is qualitatively different from ordinary light. For instance, sunlight is comprised of a variety of wavelengths that scatter in a variety of different directions.
Conversely, the light emitted from a laser is comprised of one wavelength and is of one color (monochromatic). Additionally, this type of light travels in a beam that is extremely narrow because all the energy waves are lined up on top of each other. As such, lasers are extremely easy to control, adjust, and manipulate.
1. Optic surgery
Perhaps one of the most common ways lasers have been incorporated into the treatment of eye issues is laser-assisted in situ keratomileusis, otherwise known as LASIK. The purpose of LASIK surgery is to treat astigmatism, farsightedness (hyperopia), and nearsightedness (myopia). It is a type of refractive surgery that involves the reshaping of the cornea to improve the cornea’s ability to focus the light entering the eye onto the retina.
This type of laser surgery takes just 15 minutes per eye, does not cause pain, and eliminates the need for glasses or contacts.
Lasers are also used to treat cataracts, a clouding on the eye’s lens, as well as glaucoma, which involves an increase in pressure within the eye.
Since 1994, lasers have been used by dentists to treat a variety of issues. For instance, lasers are used to reshape gums that have been damaged by gum disease. Lasers are also used to whiten teeth. In fact, with the help of lasers, teeth whitening is an in-office procedure that eliminates the need to use bleaching gels for several days or even weeks.
In terms of issues related to the skin, lasers are used to decrease the pain many people experience due to canker sores. Regarding relatively more serious issues, lasers are used to biopsy (remove) small amounts of tissue to be examine for the presence of cancer.
Finally, when it comes to cavities, lasers are used to remove the decay and prepare the tooth to receive a filling.
3. Arterial plaque
Plaque is comprised of a variety of substances, such as calcium, cholesterol, and fat. Because plaque can build up on the walls of the arteries in the heart it can cause blockages. These blockages can result in a stroke or heart attack. Traditionally, treatment has been to open up the chest and clean out the arteries, which involves several incisions. Additionally, open heart surgery can take weeks to recover from.
Fortunately, the use of lasers has proven to be an effective alternative. The procedure used to clear plaque buildup is called laser angioplasty. Through the combination of fiber optics, which allows the surgeon to see the plaque, and the ability of the laser to effectively burn the plaque off of the artery walls, there is little to no bleeding, only one incision is required, and recovery time is typically just one to two days.
The use of lasers in cosmetic surgery is very common. For instance, to permanently remove unwanted facial or body hair, a laser is used to direct a beam of light at each individual hair follicle. The energy from the laser is absorbed by the hair and transforms into heat. This resultant heat effectively destroys the hair follicle without harming the surrounding skin.
Lasers have also proven invaluable in the removal of tattoos and birthmarks, such as port-wine stains, which are reddish-purple blotches typically found on the neck and face. In regards to tattoo removal, a laser is used to bleach the dyes used in tattooing without harming the surrounding skin. Regarding port-wine stains, the malformed blood vessels that comprise this birthmark absorb the laser energy and are burned away. This procedure does not harm the surrounding skin.
5. Optical tweezers
Through the use of single-laser optical tweezers, scientists can manipulate extremely small particles in three-dimensional space without harming them. This technology is similar to the way we use regular tweezers in that the light emitted from the laser can hold and rotate microscopic objects. The use of optical tweezers has allowed for the study of microscopic organisms such as bacteria, viruses, and DNA strands.